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FAQ or Answers to Frequently Asked Questions Section 45
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Please check "root" (faq$txt) file for acknowledgements.
This is a file containing answers, tips, hints and guidelines associated
with recurring questions asked by photographers. If you would like to
add a tidbit of knowledge to this list just send it to ANDPPH@rit.edu
who will gladly add it to this collection. For complete table of content
send message to ritphoto@rit.edu with FAQ$txt in the Subject: line
These files are available in SECTIONS.
This is Section 45 and its contents are listed below.
45.01 -< The "Color Wheel" and RGB/CMY >-
45.02 -< Cameras for school use to replace the K1000 >-
45.03 -< The Business of Youth Sports / Teams Photography >-
45.04 -< Speaking engagement about photography and careers >-
45.05 -< Advice for a Figure Study Photo Workshop >-
45.06 -< Suggestions for Content of a Portfolio for Transfer Credit >-
45.07 -< Some chit chat on Fundamental Principles in Polarization >-
45.08 -< Panoramic Stitching Software - PTStitcher >-
45.09 -< Flashbulbs NOT a lost art yet >-
45.10 -< Fake Ice Cubes for studio prop >-
45.11 -< Polaroid Emulsion Lift-off Prints, short instructions >-
45.12 -< Finding the F number - instructions >-
45.13 -< Guide Numbers with multiple flashes - how? >-
45.14 -< Getting started with Volunteer Photo Teaching >-
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45.01 -< The "Color Wheel" and RGB/CMY >-
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> What is the relationship between the color wheel and terms such as RGB?
The colours of the rainbow (traditionally) are
Red Orange Yellow Green Blue Indigo Violet.
Note that these colours are strictly in order of wavelength. They go from
longest wavelength (lowest energy, lowest frequency) to shortest wavelength
(highest energy, highest wavelength).
They are also part of a continuum, with infra-red on one end and UV on the
other, and beyond them (on each side) the rest of the variety of
electro-magnetic radiation that forms the full spectrum.
And you'll also note that there's a whole host of colours missing from the
colours of the rainbow.
It just so happens that our eyes have detectors (cones) that are sensitive to
three bands of electromagnetic radiation. These bands are called red, green,
and blue. Not really because of that, but as a consequence of that, these
colours are called primary colours.
So the primary colours are RED, GREEN, and BLUE.
The bands that the cones are sensitive to overlap quite a lot. Because of that,
light that consists of a single frequency only (monochromatic light) (and light
coming from the parts of a rainbow is an example) can be percieved as having
any one of a number of colours.
Also note that what's called blue in the rainbow is really cyan, and what's
called violet is blue...
But light from objects normally consists of other than monochromatic light (in
fact it RARELY consists of monochromatic light). If we see a combination of red
and green light, our eye cannot tell the difference between that and
monochromatic yellow light, as both trigger the same response in our eyes.
Thus, we can represent any colour in the rainbow using combinations of red,
green, and blue light. But you will notice that none of the necessary
combinations include red and blue. Combinations of red and blue produce colours
that are not present in the rainbow (and are thus not capable of being produced
with monochromatic light).
In a colour wheel, the ends of the rainbow are wrapped around, and magenta
placed between red and blue (because this is what we see when red and blue
light are mixed).
So, the colour wheel consists of the three primary colours (RED, GREEN, and
BLUE) with the three secondaries (CYAN, MAGENTA, and YELLOW) placed between
them.
The way this is set out, Red is opposite CYAN, GREEN is opposite MAGENTA, and
YELLOW is opposite BLUE.
And it then happens that white light which has all the RED removed from it
appears CYAN, and so on around the wheel.
The colour wheel is of incredible importance to anyone who has ever needed to
print colour and correct colour casts! (or understand contrast filters for B&W
paper, or understand colour film (print or transparency), or...)
Also of some interest is that while we *know* that our eyes are sensitive to
red, green, and blue, that is not how we appear to process colour. Most people
see magenta as a reddish blue, and cyan as a greenish blue, but almost nobody
would describe yellow as a reddish green.
We appear to process colour information using RED, YELLOW, GREEN, BLUE -- which
is perhaps more interesting than useful (I'm sorry, I can't provide a reference
for this).
From: Steve Hodges
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45.02 -< Cameras for school use to replace the K1000 >-
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> Hi all. I am in the process of replacing what is left of a stable of
> k1000s. I have purchased several Pentax ZXMs but am now starting to
> experience so possible problems with them.
Mark Olson says: I've ordered 3 of the Phoenix P-1's with 28-70 zoom lenses
(K-mount). they're all plastic bodies, but at only $169 w/lens, I'm going to
give these a try. I have a student who bought a Vivitar that is just like it
and is within your budget.
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National Camera Institute has a repair course in a book AND a video on
repairing the K1000. It's not expensive. Maybe $100. Well worth the investment.
Would allow you to make most of the minor repairs at the school.
I purchased the materials several years ago when we were considering a class in
camera repair. I also was aware that Pentax was discontinuing the camera and we
had 60 of them that we were going to need to keep in working order.
When I got the materials, the business was run by Don Marr, 1474 West 6th Ave.,
Eugene, OR 97402. 541 683 5361.
From: Michael Pearlman
Christopher Michael Studios of Photography
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You might consider buying used Canon AE1s in good condition ($150-200). They
are far superior to anything built today at that price range.
From: Mchiav@aol.com - Mike Chiaverina
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Ricoh seems to be history too. I have seen a Phoenix brand camera that
seems to be very similar to the Nikon FM-10 and the Olympus OM-2000 (selling
at $299 w/35-70mm). I believe that all of them are made by Cosina and
understand that they all share a Seiko shutter. The Phoenix sells both with
a 35-70mm or a 50mm f/1.8 K-Mount lens and include a strap and battery (no
case). With either lens, they should sell for under $200 when they again
become available.
It is a pure manual/mechanical camera with a LCD meter al Nikon FM. Film
transport, shutter speed dial, film speed setting are all traditional
manual. I don't believe that there is a depth-of-field preview, but there
is always the partial lens dismount method.
Due to the absence of the Ricoh's and K-1000's this year, I have been told
that there has been a run on the Phoenix. They are presently sold out but
they should have more soon.
I have ordered a few of them to sell at Irvine Camera (my day job), but have
no experience with them yet. I do expect that they will be suitable for
student use.
If your local supplier needs to know how to get in touch with Phoenix,
please have them call me. They may be PMA members and therefore would also
be in the Who's Who directory.
From: Gene Pardee
Gene Pardee - Photography Instructor
Irvine Fine Arts Center - Irvine California
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45.03 -< The Business of Youth Sports / Teams Photography >-
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> Could anyone please tell me how I would go about getting into the youth
> sports photography field. Who to contact, prices, how it all works, etc.
> Any information would be greatly appreciated and thank you in advance.
If you are in the Raleigh-Durham area of NC, you have to file zillions of
pages of government paperwork, work as an apprentice for 60 years, charge four
times what I do. If your not in my market, its a lot easier :-) :-) :-)
In all seriousness, Youth Sports Photography can be a lucrative photo market.
Lets start with how to get business. A lot of it is determined by your market
and if there is need for another photographer. Here in the Triangle there are
more sports teams than you can shake a stick at. I can be as busy as I want to
be. However, when I lived in Key West, FL, there were five photographers
fighting for one 800 kid baseball league.
Here is what you need:
35mm Camera (or Medium format, but more stuff is geared toward 35mm)
a nice sharp lens. I use either my 50mm or my 35-70 zoom.
A steady tripod with a remote release.
A way to get your flash off camera (bracket, light stand, necessary cables)
A company to process and print your packages
Some good portrait film
and Business.
Lets start with the camera gear. I recommend 35mm because I've only blown up
one photo larger than 8x10 from these deals and it was a 20x30 poster. Even at
20x30 and good film, 35mm is more than enough to handle the job. You will be
shooting both portraits, typically full body, then you will shoot the team
which can require a wide angle. I'll cover shooting in a bit. Put the camera
on a steady tripod and get your flash off camera to avoid red eye.
Next you need to find a company to process and print your packages. I
recommend ProPhoto in Lakeland, FL. (1-800-237-6429). Call them and say, "Hey,
I'm a youth sports photographer from Somecity, somestate, and I would like to
set up an account and receive a catalog and starter forms." They will send you
a kit that contains order forms, order bags, negative sleeves, player
information forms (for printing the backs of trader cards, etc.), a catalog,
and other goodies. They will also give you a customer number which you need to
permanently etch in the back of you mind.
Next, you need to find work. You can contact local parks and recreation
departments, look up local independent sports clubs, swim teams, etc. You ask
them if they have a photographer. Ask if they are happy, or how a bidding
process works, etc.
I've seen leagues where they have photographers for life and you could have
the package prices and give the league a huge "fundraiser", commission,
franchise fee, extortion what ever you want to call it and you still wouldn't
get a contract. I went to a new indoor roller hockey/soccer center that just
opened and the guy was very cordial when I asked, he said "I've been using the
same photographer and I'm very happy, but if that ever changes, I have your
card". No luck there.
You will find leagues where the league doesn't want to get involved with the
photos and its up to each team to have their own photos done. In particular,
the larger the league, the more likely for them to not have a league
photographer.
In most cases you will have to submit a bid. That bid is typically an
introduction letter and a copy of your prices. If you have samples, its good
to include them. I target different price levels ($10, $15, $20, $25 and $30).
I then take the prices from the catalog, and at least triple them to see what
fits into the price ranges. Almost everyone can afford a $10 package (which
costs me $3.10 to print for 2-3.5x5 individuals, a 5x7 team, and a folder,
called a Memory Mate, to hold them and I charge $11.95). You can build as
complex a packages as you want or as simple.
When I word my bid, I don't mention any fees to the league. I will typically
offer a 5x7 team for each team for the coach or league for sponsor plaques. I
also leave the wording in the welcome letter open so that if they expect a
fund raiser, they can call and ask.
The league may not ask for any thing, or they could ask for a fortune. If they
ask for anything more than your prepared to give them, you may want to see if
you can up the prices to accommodate their "Fund raiser". I used to charge
$9.95 for that intro package, but a recent league asked for $2 per package.
Since then my bank has really upped my per check deposited fees, so I've moved
my base price there and no one has flinched or complained.
Any way, once you start this, you also head down the governmental pain in the
behind road. If your state collects sales tax, you will have to get a TaxID so
you can collect sales tax and pay them accordingly. To do this, it may require
an occupational permit from your local municipalities (not needed in all
communities). If you go this far, and you want a business name more than "Your
Name, Photography", you may have to file fictitious name documents and deal
with that paper hassle. I had to do that in Florida, but not NC. Of course,
this also means the end of the dear ole 1040-EZ and 1040-A form, and welcomes
in the "Long Form" because you need to report this income and you want to
expense away every penny you can. (This is the scarry stuff, but its not that
bad, really, however you don't want to take the chance that the kid you are
taking photos of has a parent who works for the IRS, or Department of Revenue
and you appear to be taking untracked money).
Ok, you've got your Lab on board, your all legal with the government, and
you've got your first team/league to shoot. Whats next?
Before you head out for the first shoot, you will need order forms (trying to
fill out the lab's forms in the field is crazy). This will have your packages,
your prices, your sales tax rate, a location for the customer's name, address,
phone number, and relevant team info: team name, coaches name, Jersey number,
position, home town, etc. You want the kids to have the order forms at least a
week before the shoot if at all possible. You will need business cards and
other stuff (stamps to endorse checks, etc.)
You will probably need an assistant to take the orders and money while you
shoot. These shoots are typically fast paced, short shoot window events. You
may only have 15-20 minutes per team to do the job. My wife helps me, so some
extra goodies in her Christmas stocking helps me avoid hired help. In our
team, she handles the customers, I take the photos and I do most of the paper
work.
Okay, its the day of the shoot. Arrive as early as possible to set up. You
will need to scout out a place to shoot. You want a clean background, fitting
in the venue if possible, i.e. for Baseball, you might want the kids standing
at Home Plate. For indoor sports, I want to set up a backdrop, studio lights,
etc. Find a place where you can line the kids up at the order table and they
can come in for the shoot. You do a lot of these as the sun is setting which
is great for color, but horrid for squinting eyes. I try to get the sun far
enough behind the player to give them a nice hair highlight and use my lights
to fill in the shadows. You can visit http://www.photo-miracles.com to see
some samples. These are not necessarily my best shots, but are representative.
You might shoot one team a night, or several teams, or you might have a
picture day (or two) to get all the kids prior to games over a very short
period. You need to be flexible because each league will operate differently.
As you bring the players up, take their photo, note the frame number on their
order form. In my case, my wife writes the frame number on the order form and
if I have to take more than one photo (eyes closed, bad pose, etc.) I yell out
"Edit" to her, and she will note the fact that I shot Billy with frames 8 & 9
so I can note that on the lab order. One photo per kid unless you mess up. Its
important to keep the frames in order. Some packages are only available from
unprocessed 35mm film and if you mess up and have to develop locally to figure
out the frames, you may loose the ability to deliver some of the packages.
Any way, this is cattle line photography, line 'em up, shoot 'em, move 'em
out. How successful you are depends on balancing shooting 12-20 kids in 20
minutes including the team photo. There isn't a lot of time for two or three
frames per kid. Work for a good consistent standard pose or set of poses get
them there, shoot and go on.
If I've got two teams back to back, I will typically shoot the first team's
individuals, followed by their team shots (usually three frames, note on your
order from what they are). Then I unload that roll (one team per roll) load
up, shoot the next team's three team frames, then the individuals for the
second team. This may seam strange, but kids show up at different times for
their practices to begin with and now you want them there 20-40 minutes early
for photos. So as team one trickles in, shoot them, buy the time you are
through with them, they should all be there, as well as all the kids for the
second team, so on the second team, shoot the teams first then the kids can
get to their warm-ups and practice/game.
If you have two cameras, you can shoot one team on one camera and the other on
a second camera, but you have to be VERY careful to not put the wrong kid on
the wrong camera. In this scenario, you can shoot the two teams as they both
arrive and then do the teams at the end for both. I've done this before and it
works, but you have to focus quite a bit more to keep two cameras and two sets
of orders working at once.
Once your done, double check to make sure all the frames are right and you
have every one. Make sure to shoot every one even if they don't want photos or
if they didn't know about it. The parents may change their mind later and
since you don't print frames with no orders, it doesn't cost you anything to
get their individual. If you don't have it and they want it, you've lost a
sale. If you have their photo and they don't want anything, you've lost a
frame of film.
I ask for payment up front and try to avoid mail ins. This is more important
when you are first starting then after you have an established bank account,
but get the money first. Some photographers are now shooting all the kids,
printing proofs and then getting the order forms and proofs to the parents.
More up front cost, but supposedly it causes higher sales. I don't plan on
doing this any time soon. Put the money in the bank, and mail out the orders
as quick as you can. I tell the parents that there is about a 3 week turn
around (so its best to start this early in the season).
When the photos come back, assemble the packages, stuff in business cards, and
fix up any mistakes (you will make them, I still do). Shoot for 100%
deliverables and good quality. Before you know it, business will be coming to
you. Each team will have a team manager or team mom that you will probably
work with. This manager deals with the running of the team so the coaches can
coach. I typically try to get the packages back to the team manager and let
them deliver to the parents.
Remember the Kenny Rogers song "The Gambler": "Don't count your money while
your sittin' at the table, there will be time enough for counting when the
dealing's done". Go home, do your accounting, deposit the goodies, plan your
next vacation or whatever you need/want to do with the cash.
Of course you meet a lot of people and if they are happy with your work, more
keeps coming.
I can answer more specific questions if you have them . . .
Rob Miracle
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45.04 -< Speaking engagement about photography and careers >-
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> I have been asked to speak to young people (teenagers) about job prospects
> for future photographers and careers in photography.
> Have any of you given such a presentation? If so would you please give me
> some ideas as to what the students were most interested in hearing about.
> What areas will photographers be in demand in the future?
> What areas of photography are most promising for future photographers?
> What are the chances of a young person having a career in photography if he
> or she cannot afford to get a college degree?
Photographers are not in demand now. They will be less so in the future. It
is competitive and getting worse everyday. 10% of all people that set out
to be photographers make a living and 2% make a good living (above $45,000)
--
Randy Little - R.S.Little Studio
Photography & Digital Imaging - http://www.rslittle.com
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I gave one yesterday -- I have to say that this is a perfect opportunity to
tell young photographers that if they don't learn about computers and very
importantly, how to use a Mac and work with Photoshop, it's quite likely they
won't have a place in photography in the next century. IF there's anything they
can be told not to concentrate on, I'd say it's how to print color in the
darkroom.
Jan
--
faces 'n places http://www.artfaul.com
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45.05 -< Advice for a Figure Study Photo Workshop >-
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> We are thinking of putting on a figure study workshop for the memebrs of our
> club. Any advice from those of you have organized such events?
Speaking as one who has attended a figure study workshop, I would make several
suggestions:
1. Have a clear schedule, i.e. shooting in the morning, review in the
afternoon or vice versa.
2. Spend some time in the beginning discussing nude work and various styles of
photography in shooting the nude figure. Engage the participants in
discussion: don't give a lecture. Show various photographer's work and have
students bring work of their own to share and show.
3. Make sure the leader of the workshop is involved but not pushy. There's a
fine line between invading the students' space and being intelligently
involved and ready with an answer and encouragement when needed.
4. Don't make students bring a certain kind of camera. Let them have the
cameras of their choice, although encouraging them to think larger format would
be a plus but 35 mm is fine.
5. Instead of sharing a model between students, assign one model to two or
three students for the duration of the workshop. This will yield greater
benefit s as a relationship will develop and the student will learn to respond
to this particular model instead of having to adapt to a different body, and a
different personality in a short space of time.
6. If possible, have contact sheets from the previous days' shoot ready each
morning for review. This critique by the leader is invaluable for the
students' growth. If it's just a one day workshop, then concentrate on shooting
strategies instead.
Most of all, be available for the participants to allay anxiety, answer
questions and trouble shoot. Get models who are flexible, calm and ready for
anything (including a lot of inexperienced photographers falling all over them
selves to shoot models!). It's best if the models are given breaks and it is
very important that the participants are told ahead of time to treat the models
with respect and the utmost courtesy. A short course on how to direct a model
in a shoot is in order beforehand.
Good luck!
Bib Scheide - portfolio at http://www.scheide.net - bib@patriot.net
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45.06 -< Suggestions for Content of a Portfolio for Transfer Credit >-
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> What should a portfolio for consideration for admission or transfer credit
> from one shool to another consist of? I have been told by a number of people
> that the portfolio should be a cohesive body of work........and some people
> have told me that it should be a variety of images. Any thoughts?
Good question. At RIT's School of Photographic Arts and Sciences portfolios are
only required if you transfer. Assuming this is waht you are doing, then my
limited experience in seeing what is submitted is that ..... they are all over
the map!!!!
I would suggest a high quality presentation with images demonstrating mastery
of the medium to the extent that you have been involved with it previoulsy.
People, landscapes, architecture, product photography and PJ type stuff.
Digitally altered images probably are the least interesting at this time. If
you have medium or large format experience be sure to include sample of this
too. Images need not be very big ... maybe up to 8x10 or 8x12 in size placed in
an 11x14 inch portfolio. The photos can be in a "book" style presentation or as
separate pieces in a display box.
I have also seen slide pages to show off color work although if at all possible
I'd include some color prints as well (if you have done work in this area).
Do not include "travel shots" or family-type photos unless stunning. They tend
to be "downers" to evaluators.
Again, presentation is very important. Clean, spotted prints. Full tonal range.
Good black shadows where needed and clean highlights where appropriate.
The total number of prints should be in the 15 to 25 range in my opinion.
Slides additional.
Please note that this is my personal opinion. Portfolios are primarily used by
students entering the "shooting" programs such as advertising, fine art and PJ
programs.
hope this helps,
Andy Davidhazy
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here is another bit of advice about portfolios from and independent source:
The advice *I* received was that *something* should tie the folio together. And
it should be more than a collection of random works.
All of my images were mounted the same way (window mount), with coloured mattes
ranging from beige to brown. Within the folio I had a couple of images forming
a series, another group of images on a different theme, and a few that were
just independant.
I spent a lot of time arranging the folio in an order that made the images (in
my mind at least) fit together with the least amount of dramatic change between
images. I also kept in mind the colours of the mattes that were places next to
each other so that the change in matt colours didn't detract from the images
themselves.
I broke my own rule and included an image that really looked a lot better with
a black matt. I shouldn't have, because it was singled out and criticised, and
then is was taken away by the person assessing the folio (well one of the three
actually) with the remark -- well that looks a lot better now. (Then it was put
back with the comment "but that's what we have to judge")
Things I've learned from this.
0) make sure it's your best work. If you can find a fixable fault with
your work (that should be darker, I wish that was more in focus, I
should have cleaned the neg, the mounting is crooked, fingerprint...)
then fix it or remove it.
1) not all images that are good belong in your folio.
2) don't make you're life hard by having a rainbow of matt colours (a
single colour (suggest white or just off-white) is sooo much easier)
3) make sure the focus remains on your work, not how you did it, you
mounted it, whatever...
4) think carefully about how you will arrange the work within your folio
(this may or may not be possible depending on the folio will be
viewed/judged)
5) show other people and listen to what they say.
6) don't break the rules you impose on yourself.
7) make sure your mounting is perfect
8) know the story of each image or series. have something interesting
or intelligent (and relevant) to talk about. Make it obvious that you
not only take great pictures, but that you also know what's going on.
9) be sensitive to the fact that nobody else may share the emotional
attatchment you have to an image. The image may mean everything to you,
but nothing to others.
None of this may apply to you... but I hope it helps.
From: Steve Hodges
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45.07 -< Some chit chat on Fundamental Principles in Polarization >-
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From: JimThyer
Steve Hodges wrote:
> Bob Blakely wrote:
> >
> > For an example experimental verification of the predictions of both the
> > particle nature of light and the Hinesburg Uncertainty Principle using
> > common photographic paraphernalia, Obtain three linear (*not* circular)
> > polarization filters. Set up two filters in a row with space for the third
> > filter between them. Darken room save for a single light source in line with
> > the two filters. Observe a light source viewed through both filters and
> > rotate one so that minimum (nearly no) light is transmitted through both
> > filters. This occurs when the filter polarizations are orthogonal
> > (polarization axis 90 deg different) from each other. (Perfect filters
> > aligned in this manner would pass no light, but there are no perfect
> > filters.) Now take the third filter and without disturbing the alignment of
> > the first two, place it between them. Rotate the third (middle) filter until
> > the light is clearly seen as significantly brighter than with the first two
> > filters alone. This occurs when the polarization axis of the third (middle)
> > filter is 45 degrees offset from the other two filters. Light! Somehow a
> > polarization component of light that did not previously exist has
> > materialized! How?!! I will leave it to any physicists in the group to
> > explain what happened.
>
> This might be complete and utter rubbish, but here goes.
>
>
> When light passes through a polarising filter, conventional wisdom tells
> us that the "correctly" polarised light goes straight through, and light
> whose polarisation differs is attenuated in proportion to to some
> function of the difference between its polarisation and the "correct"
> polarisation.
>
> However this process is (in quantum terms) an act of measuring the
> polarisation of the light. Now quantum mechanics tells us that
> measuring things changes them. And at a quantum level it can change
> them quite dramatically.
>
> Thus, it seems likely to me, the polarising filter randomises the
> polarisation of the light, with the resulting "mix" of polarisation
> matching what we would "expect".
>
> Thus (big jump, because I'm off to work) the three polarising filters in
> a row would act to effectively rotate the polarisation of the light.
>
>
> Steve
This is perfectly correct. The first polarizer sets the plane of polarization
of the beam after it passes through. A second polarizer will allow a
component of the first beam through, on a [cos(theta)]**2 rule. As cos 0 is 1,
if the second polarizer has its plane of polarization parallel to the first (at
zero degrees) there is no reduction in light intensity, and the plane of
polarization is the same.
If the second is set at an angle then the component of the first along the
plane of the second passes through, the perpendicular component is blocked.
Thus some of the beam is allowed to pass through. (with reduced intensity
according to the rule above). The plane of polarization now becomes that of
the second polarizer.
On reaching the third polarizer the same happens again. The component of the
beam parallel to polarizer 3 is passed through, so in effect the plane of
polarization is rotated through 90 deg.
Having retired and moved I can no longer find my basic reference (B. Bleaney &
B. Bleaney, Electricity & Magnetism, Oxford University Press.) If I could we
could do a full mathematical proof..
Jim Thyer
--
*******************************************************
Jim Thyer email: jimth@tpgi.com.au
(Formerly Info Tech & Math Sciences
University of Ballarat {Retired})
6 Beach Close, Pt. Lonsdale, Vic 3225, Australia
Ph: 03 52583213
*******************************************************
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From: chandler@yomogi.or.jp (chandler)
Steve Hodges writes (of polarising filters):
[snip]
> However this process is (in quantum terms) an act of measuring the
> polarisation of the light. Now quantum mechanics tells us that
> measuring things changes them. And at a quantum level it can change
> them quite dramatically.
[snip]
I'm a bit lost as well, but I don't think you need to invoke quantum mechanics
to get this effect.
Consider a rope, set up in a suitable medium (treacle? dunno: this is a thought
experiment) to transmit waves by the mechanisms of totally classical physics. A
fairy waves one end around in all directions, and waves pass along the rope, as
calculated by solving those differential equations I've forgotten all about.
Now arrange that just in front of the fairy is a big board with a vertical slit
in. Only the vertical component of the wiggles will pass through the slit. Now
somewhat downstream from the fairy put another board with a horizontal slit in.
Since the wave reaching it is purely vertical, more or less nothing will pass
through. So the two boards constrain the rope in such a way that no wave comes
out at the far end.
Now between the two boards add another one, with a slot at 45 degrees. This is
a *further* constraint on the movement of the rope. However, now when the
vertical wave arrives at the 45-degree slot, a certain component of it
(sin(45deg) or 1/root(2)) is in the diagonal direction, and thus a somewhat
reduced wave will go through *at 45 degrees*. When this wave hits the far
(horizontal) slot, again a component will be horizontal (sin(45deg) again) and
will go through. So what should come out at the far end is reduced by two
factors of root(2), which of course means 1/2. I'm sure some ingenious person
can think of a quick way of checking this numerically with a lightmeter of some
sort.
Brian Chandler
geo://Sano.Japan.Planet_3 http://www3.yomogi.or.jp/chandler/
=============================================================================
45.08 -< Panoramic Stitching Software - PTStitcher >-
-----------------------------------------------------------------------------
From: Helmut Dersch
Subject: [ANNOUNCE] PTStitcher
Announcing PTStitcher, the simple stitching utility. Drop your images onto its
icon, and get a panorama ready to be viewed by all major plug-ins. With
multirow stitching capability, all lens type support, cylindrical and
spherical formats and much mo re.
Output options:
===============
o QTVR movie ready to be viewed with Quicktime plug-in.
o Smoothmove full spherical panorama ready to be viewed
with Infinite Images (iMove) plug-in.
o RealVR full spherical panorama ready to be viewed with
LivePicture's ZoomIt viewer.
o Panoramic images for viewing and printing
o Multilayer Photoshop file containing one image per layer for
editing.
Input options:
==============
o Rectilinear lenses with any focal length
o Fisheye lenses with any focal length
o Panoramic cameras
o Any orientation possible (multirow etc)
o Can read PICT and JPEG images.
Tutorial examples included:
===========================
o Making panoramas using two rows of rectilinear images
(aka Kaidan/Smoothmove).
o Making panoramas using two fisheye images
(aka ..forgot it).
PTStitcher v1.0b0 is free, and available for Macintosh (PPC, System > 7.6)
from
Enjoy
Helmut Dersch
-------------------------------------
Spherical Panoramas, Macro Panoramas,
Free Panorama Software:
=============================================================================
45.09 -< Flashbulbs NOT a lost art yet >-
-----------------------------------------------------------------------------
From: William Cress
FLASHBULBS - Reminiscent of the 50ās and 60ās the interest in and use of
flashbulbs has dramatically increased in the 90ās. You probably remember the
"pop" of a flashbulb and the "feel good" sense of accomplishment when it
worked. Almost a lost art, flashbulbs are making a comeback and Bill Cress,
president of Cress Photo is discovering that itās not just photographers who
are buying and using them again. Its nostalgic, creative, dramatic light and
they are powerful. "The use of flashbulbs requires a basic knowledge of film,
lighting and camera functions" says Cress, " and for many adults the
accomplishment of superb images using bulbs is linked to many happy childhood
memories."
To link the pleasures of flashbulb use to modern times, Cress Photo has
assembled a substantial inventory of every type of bulb ever produced. The
company is able to supply technical information on usage, and customersā
requirements on a worldwide basis. A new web site, http:// www.flashbulbs.com
provides specifications and basic information for users starting out. Compact
and more powerful than most electronic strobes, flashbulbs offer ease of use
without a lot of equipment or access to a wall outlet. They are being used for
general photography, photographing trains, underground caves, by divers
underwater, scientific research, by testing companies, for stage and motion
picture effects, model rocketry, high speed filming, laser research, marching
bands, and silk screeners to name a few.
Cress Photo, a division of Lite Station USA Inc.
PO Box 4262, Wayne New Jersey 07474-4262
Tel: 973-694-1280 Fax: 973-694-6965
=============================================================================
45.10 -< Fake Ice Cubes for studio prop >-
-----------------------------------------------------------------------------
> I have a great idea for a photograph that I have wanted to do for about a
> year. I haven't tried it yet, but I thought you people could probably help.
> The photo will be a glass with a little bit of condensation on it. First,
> whats the best way to get the condensation? Second, how can I make, or where
> can I get a "perfect" ice cube? The perfect cube would be almost square,
> mostly clear, and have smooth curves (like it sat melting for just the right
> amount of time). Because I want to be able to shoot this for around an hour,
> the ice shouldn't melt..
Trengrove manufactures beautiful, handmade cubes. They are very expensive
(depending on size and type, $30-$40 a cube) but when you shoot for a
living, the cost is really nothing as you will be using them again most
likely. They are available from Calumet in Chicago, or directly from
Trengrove. When I find what I did with their brochure, I will send you
their address. For a good look in condensation, mix a bit of glycerine with
DISTILLED water. Mix it thoroughly and spray it on, use your hand or a card
or something to control overshoot. You need distilled water because it will
not leave a stain, and the glycerine helps in keeping the droplets in place
on your glass, also as the water evaporates, it will do so more slowly, but
you will still have glycerine droplets on your glass (believe me, no one
will know).
good luck
From: Paul Aparycki
------------------------------------------------------------------------
Condensation can be sprayed onto a glass with a small spray bottle like
is used for plants. Calumet has some fairly realistic fake ice cubes.
From: Terry Smith
------------------------------------------------------------------------
You can get fake ice. The one I saw most recently is soaked in water
overnight. This stuff doesn't melt :-) It's also not cold, so it won't create
condensation.
For the condensation you might try a hand operated spray pump thingy (the ones
that window cleaners and the like come in). Spray it on the item you want
condensation on. Experiment... Play...
But I think that lighting is the most important element in an image like this.
Everything is clear. You need to make it look natural, AND have enough
contrast to be recognisable (and look good) AND not have distracting
reflections, backgrounds etc...
Is this going to be B&W or colour. I suggest bracketting your shots. Your
meter may tend to underexpose this type of shot.
Steve
From: Steve Hodges
------------------------------------------------------------------------
Go to a theatre props rental house, they have all sorts of "perfect" ice
cubes.
Pierre Clemente - Imagepoint Photography
From: Imagepoint Photography
=============================================================================
45.11 -< Polaroid Emulsion Lift-off Prints, short instructions >-
-----------------------------------------------------------------------------
> What are the basic steps required to make Polaroid Emulsion Lift-off prints?
Here are my techniques for teaching Polaroid emulsion lift. Good luck!
Burnish a piece of contact paper to the back of the polaroid to prevent
chemical leakage. Float the fully developed polaroid in boiling (180 degrees)
for a few minutes until the surface starts bubbling and lifting off the
backing. At that point, using tongs, carefully lift the entire polaroid out of
the boiling water into a tray of warm water (which allows you to be able to
put your hands in the water safetly.)
With the soft underside of your fingertips, gently push back the emulsion from
the corners until it is freed from the backing. I usually lift the floating
emulsion out with a clear piece of acetate. Once it on top of the acetate
(it's pretty slippery and delicate so be careful not to tear it), you can
smooth out the image and flip it over on any substrate you desire--paper,
glass, fabric, wood, tile, etc.
It takes a little bit of practice, but it's a fairly simple process.
Linda Soberman
From: CASLIN123@aol.com
=============================================================================
45.12 -< Finding the F number instructions >-
-----------------------------------------------------------------------------
> how do you determine the f/stop? What about lenses that don't have a focal
> length?
Well, for this you first determine the approximate focal length. With simple
lenses such as in box cameras etdc. it is simply the distance from the lens to
the film polane. Now you need to determine the diameter of the aperture.
Take a pin and make a small hole in a piece of aluminum foil. Place this foil in
the film plane of the camera centering the pinhole. Place a bright flashlight
as close to the pinhole as possible. Assuming you open the shutter at this time
you should see a circle of light projected by the camera lens onto a piece of
white paper placed in front of the lens. Measure the diameter of this circle.
Divide the FL by the diameter of the aperture and that is the f#.
hope this helps,
Andrew Davidhazy - andpph@rit.edu
=============================================================================
45.13 -< Guide Numbers with multiple flashes - how? >-
-----------------------------------------------------------------------------
> So how does one calculate an aperature using multiple bulbs (on camera). If a
> #5 bulb has a guide number of 450, intuition would say "Hey double it to
> 900" That's wrong.
To add guide numbers, take the square root of the sum of their squares.
> I've been calculating it by using guide numbers backward. i.e. If one has a
> guide number of 450 then the f-number is f45 @ 10feet. With two bulbs of the
> same size, I've doubled the light, the aperature moves one stop to f64 then
> multiply by the distance (10 feet) to get a new guide number of 640. It
> works, but I suspect there is a more.... er... 'mathmatical' solution.
GNt = sqrt(GN1^2 + GN2^2 + ... + GNn^2) where GNt is the total Guide
number, GN1, GN2, ...GNn are the guide numbers.
So to get the guide number of two gn 450 bulbs:
GNt = sqrt ( 450^2 + 450^2)
= sqrt ( 202500 + 202500 )
= sqrt ( 40500 )
~ 640 (actually 636.3961...)
The easier way for flash units (including bulbs) of the same power is to
multiply the guide number by 1.4 for each doubling in the number of flashes. So
one Metz 45 has a guide number of 45, 2 have a gn of 63, 4 have a gn of 90 and
so on.
The calculation is easier if you have a number of flash units that is not a
power of 2 (actually the easy way here is to multiply by the square root of the
number of units) or where the power is not equal.
So a gn 40, 64, and 32 combined give sqrt ( 40^2 + 64^2 + 32^2 ) = 82
These calculations only apply where the flash units are being used to
illuminate the same object. If you have a large object and you need multiple
flash units to cover the whole thing, then you don't add the guide numbers
using any method.
Also note that guide numbers tell you how far to place the flash from the
subject for a given aperture, not how far away to place the camera. The camera
position is independent (ok, so it's got to be on the side that's illuminated
:-)
Steve
p.s. a Metz 45 placed 4 metres away from a subject provides the correct
lighting for an observer on the moon using a lens at f/11 @ 1/60 (I would
recommend a tripod)
p.p.s. Don't do a NASA (especially if you're trying the above from Mars). Make
sure that if you're adding guide numbers (or using them for that matter) that
they're all in metres (or feet) and all for the same ISO film.
gn ft -> gn m divide by 3.28
gn m -> gn ft multiply by 3.28
gn ISOa -> gn ISOb multiply by sqrt(ISOb / ISOa)
=============================================================================
45.14 -< Getting started with Volunteer Photo Teaching >-
-----------------------------------------------------------------------------
> I am volunteering to be a mentor to some high school students by exposing
> them (excuse the pun) to photography. I will be supplying the students with
> cameras, film, etc., on my own at first (I hope to build this program enough
> so I can ask for assistance from the community/schools/businesses as far as
> supplies go in the future).
>
> I've tutored adults before, but not young people. If any of you have taught
> young people, would you please give me an idea of where (camera? film?
> exposure? lighting? shape,form,composition?) and how (classroom? field
> trip? lecture? reading assignments?) you started. I won't have much time
> with the students--maybe one hour a week unless they would be willing to
> meet with me on their free time.
Something to consider is using disposable cameras - yeah, color, but kids today
think in color. Perhaps you could get a dealer to donate the cameras and
processing.
Then, you might think about turning them loose to photograph each other. Give
them an assignment to pick one friend and tell a true story about that friend in
pictures. Have them assemble the pictures, and when show-and-tell times comes,
have them talk through why they took the pictures they did. What are those
pictures saying about their friend.
As to reading assignments, I would suggest telling them to go through fashion
magazines and pick pictures they like. Why do they like those pictures - what
is there about them that makes them appealing?
The one thing I would avoid at first is heavy theory. There will be time for
that later after the kids understand the magic of creating an image. One
approach to treating those things is to compare their efforts with pictures that
they really like.
After you do individual assignments, then you might do a group shoot using one
kid as a "model". Normally, teens are reluctant to be photographed, but as
they get turned on to photography, that reluctance will disappear. Once that
happens, they really do loose a lot of inhibitions - the challenge for you will
be to be as open minded as they will be!
You might also consider making the final objective of the program to create a
web page of the images - a day in the life, etc. That is something that the
kids really will relate to (more so than magazines) and they will be more likely
to get excited about doing it.
I would like to see the results - I've been thinking about doing something like
that myself and would like to see how your effort turns out.
=-=-=-=-=-=-=-=-=-=-=
Louie J. Powell, APSA
Glenville, NY USA
http://www.geocities.com/Paris/Maison/7881/
----------------------------------------------------------------------------
I would suggest maybe you get them all Holga's (the new ones that cost 20
bucks. or have them buy them.) I can give you the number of a place here
that sell them.)
From: Randy Little
-----------------------------------------------------------------
Dont be surprised if they reject your subject completely! You can get close
to teenagers through photography as they are given an opportunity to express
themselves. Give them some freedom of expression within limits of a
project - "show wealth and poverty (contrast)" "Illustrate a street market
from dawn to dusk"
From: Chris Strevens
--------------------------------------------------------------------------
What a fine thing you are doing! But are you going to overload? Cost to
benefit of loading all those cassets? Your time might be better spent
seaking a deal or gift from local photoshops or labs. Even manufacturers
might help if you write and ask, all they can do is say no, or maybe YES!
Also check with the film dealers in Shutterbug who have slightly out of date
film. Heck, even some of the list members might send a roll or two! As to
cameras, don't rule out the possibility that teenagers might have their own
P&S or be able to borrow a basic 35 from parents or other friends and
relatives. If you can teach them to load, compose, focus, expose, load a
nikon reel, devolope, dry, proof, enlarge,and find their own way to and from
a good photo dealer, you will have done MORE than enough! What a fine thing
you are doing. My hat is off ot you!
From: Donald MacMillan
-------------------------------------------------------------------------
Hmmm, the problem with these (cheap plastic cameras) is that they're all fixed f
ocus and often
have a single shutter speed/aperture. This is fine for nasty colour
prints, because the machine can salvage an image off almost anything.
You, however, might not appreciate it if you're printing them :-)
> I also believe the more basic the
> equipment, the more grounding in photography they will receive. I don't want
> to go the pin hole camera route--that's a complete project by itself.
Personally I'd try to beg, borrow or steal some manual SLR cameras with
some kind of needle or stick and ball meter. The down side is that
you're likely to get a mixed bag and the instructions for use will
differ for each one :-(
See what the kids can come up with.
> Black and white film will allow me to do the processing and proof sheets,
> saving the expense of a lab, and I can load film cassettes at home, saving
> more.
Good idea. It's also easier to pass around proof sheets so everyone can
see them.
> I've tutored adults before, but not young people. If any of you have taught
> young people
Do my kids count? They were only 7 and 10 when they figures out the
manual focus auto exposure camera, and about a month older when they
figures out the manual focus, manual exposure camera.
Their best shots are from the all manual camera.
>, would you please give me an idea of where (camera? film?
> exposure? lighting? shape,form,composition?) and how (classroom? field
> trip? lecture? reading assignments?) you started.
-1) get them to bring in any photos they have already taken with any
type of camera.
0) show them some photos that YOU have made from the same type of
equipment that they're going to use.
1) basic instructions - how to focus what the image looks like when it's
focussed)
2) how the exposure thing works (start with fixed shutter or aperture
that you select and get them to alter the other until the exposure is
"correct"
3) warning on too slow shutter speeds
3.5) how to take picture (stand still, gently squeeze...)
3.7) (lie) tell them film is valuable, try to make each shot count
They need to shoot off at least one frame after being told 1 to 3.5,
even if it's just a quick picture of a tree outside.
4) take them out on a walk around some familiar area (even the school,
but I would recommend walking along the streets. Take pictures of
things you see. YOU take pictures too.
Don't tell them anything about composition. Get the mechanics right
first. Kids are awfully creative, and you don't want to beat any more
creativity out of them.
Talk about that after they see the results. Why are some shots better
than others? Make composition something that sounds positive rather
than a lecture about rules and regulations.
> I won't have much time
> with the students--maybe one hour a week
Not long :-(
> unless they would be willing to
> meet with me on their free time.
you may be surprised :-)
> My hope is for them to have finished prints for a "show" by the end of their
> time with me. Thank you in advance.
Are you teaching them to print too? Or are you (I assume) going to
print the best of them?
Steve
From: Steve Hodges
--------------------------------------------------------------------------
I have worked with young people teaching photography...I worked with my
daughter's scout troop as well as with a group of yearbook photographers for
her grade school...mostly 7th and 8th graders.
I began, as you will, very simply...the basics of how to hold a camera for
good, non-blurry shots, how to load film, how to use the flash, how to advance
and rewind the film.
I spent time looking thru magazines for photos that illustrated concepts I was
teaching...good composition, good lighting, portraits, landscapes,
architecture, sports. I allowed the kids to ask me questions in addition to
the questions I asked them. I brought in some of my own work to share.
I always did my teaching of the "concept" in a classroom because I could use
the chalk board and they could sit comfortably ...taking notes if they liked.
I would pick an area...motion, light, sports, portraits, pets, friends, a
storyline and assign them to shoot it...you will be amazed at the variety of
the results..I always was!
My kids all shot color and were responsible for their own processing...but
since you will be doing this end for them, you may ask if there aren't one or
two who might be interested in helping out...that's how I started my photo
training and I will never forget it!
Lea
From: LMurphys@aol.com
---------------------------------------------------------------------
>I always did my teaching of the "concept" in a classroom because I could use
>the chalk board and they could sit comfortably ...taking notes if they liked.
For Marilyn, Lea and anyone else who teaches beginners:
I've just discovered a very nice teaching aid for beginning photography.
It's called the Canon Photograpic Workshop, and it's a CD-ROM that covers
all the basics -- light, film, exposure, depth of field, lenses, shutters -
the whole works. I ordered it from Calumet for $19.95, and plan to use it
in my beginning photo class of college students. I think it would work well
with younger kids, as well. The graphics and examples are first-rate.
----
Phil Vinson - Fort Worth, Texas USA
Photographer
Lecturer in Photojournalism, University of Texas at Arlington
Photo Galleries: http://www.flash.net/~pvinson
e-mail: pvinson@flash.net, pvinson@uta.edu
----------------------------------------------------------------------------
I'm getting ready to do a similar project and the folks who put it together
use Holga cameras. They cost very little from Freestyle and are an old
standard for teaching. There is a lot to be said for the large negs. You
could order a bunch of white box 120 film also rather cheaply from them.
There is a cheap 35mm camera available also from Freestyle. There is a big
cost advantage to home loading 35mm. My favorite trick is re-using the
cassettes I get from the photo labs. (I'll explain how that is done needed)
I have often opted for home-loads in a teaching setting just to save the
kids a few bucks. I can load a roll in 20 seconds or less and it costs
about $1.50 a roll. I would never lend a camera to a student that I
didn't want ruined. I have had bad experiences with ham-handed oafs.
As far as explaining the basics, I would keep the lesson to two or three,
one-page handouts: judging light/exposure, stopping action, and composition.
Anything more for an enrichment class is too much. The students will mostly
want to photograph each other. I wouldn't show them ANY photographs until
they have spent some time using the camera, then bring in some books and let
them decide which pictures mean something to them.
Check out this terrific web site:
http://dir.yahoo.com/Arts/Visual_Arts/Photography/Toy_Camera_Photography
Freestyle: www.freestylesalesco.com
From: Alan Zinn
-------------------------------------------------------------------------
May I suggest that for a field trip you take them to a place where there
are statues? Great for how light affects details. Maybe you could divide
up the course into Subject/Interest, Composition, Technique
From: Palma Allen
--------------------------------------------------------------------
I had same task some years ago.
Problem: 40 kids, 2 week maximum project time. $200 budget.
1. Bought 6 manual 35mm cameras ( w light meters) from pawn shop.
100' roll of Plus-X. 2 boxes of 100 shts enlarging paper, D-76, Dektol.
Brought trays, thermometer, stop bath, filters, etc. from home.
2. Explained light meter, camera operation, and composition.
Gave written quiz. Top 6 got cameras overnight:
Assignment: Photograph yourself, and your friends.
3. Processed film and made contact sheets with first 6.
4. Made comments on focus, composition, lighting etc. daily,
till all 40 had taken a turn. Made 8 x 10 prints daily.
5. Third and fourth days of second week was for reshoots
and slow learners.
6. Fifth day of second week, project posted. Returned $30
and four cameras to school. (1 trashed, 1 "borrowed").
From: Al Doyle
=========================== end of section 45 ==============================
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