From: amolitor@nmsu.edu (Andrew Molitor)
Subject: rec.photo Frequently asked questions and answers
Keywords: frequent questions
Organization: New Mexico State University
Date: Fri, 16 Oct 1992 04:48:20 GMT


	Amazing, I am posting this on time..

	There is now a rec.photo archive containing a few little items
of good stuff on my workstation -- moink.nmsu.edu (128.123.4.58) for
anonymous FTP. Submissions for it are more than welcome! No gifs, please.
I have 40 megabytes or so free, and can't really spend it on pictures.

	As always, thank you, everyone, for your continued suggestions
regarding this little sheet.

	Andrew

------------------------------------------------------------------------
>>>> Contents
------------------------------------------------------------------------

	Some rec.photo generalities
	Other photo informational sheets, and mailing lists
	A short lexicon of terms
	Some useful phone numbers
	Some miscellaneous questions
	Equipment - brands, purchasing and quality

------------------------------------------------------------------------
>>>> Some rec.photo generalities
------------------------------------------------------------------------

Kodak Publications

	These are recommended so often that the fact of their existence
	is worthy of a spot here. Kodak publishes a large set of pamphlets
	on various subjects photographic, from how to dispose of darkroom
	chemistry to how to take pictures of monitors and TV screens.
	Some are free, the rest are cheap. All may be obtained from
	1-800-242-2424, easily. The catalogue of publications is designated
	L-1, and may be obtained free.

How to ask a question in rec.photo

	This may seem silly, but a surprising percentage of questions
	asked in this newsroup are ill-phrased. In an effort to help
	this problem go away, I suggest:

	1) specify make and model of equipment
	2) specify exact film type (read it off the box!)
	3) specify exact camera settings
	4) be as detailed as possible about the circumstances and
		failure mode/problem.

	Try to get the terminology right -- look it up if you're not sure!
	In short, provide as much detail as possible.

Is it OK to flame in rec.photo?

	No ;) We don't flame in this newsgroup. Really! This is one of
	the very few unmoderated newsgroups with almost no flame content.

Hey! Let's split rec.photo up in to several groups!

	Periodically, people suggest that rec.photo get split up.
	The consensus generally arrived at is 'no', and the reasons given
	are many. The big ones seem to be: Too many different ways to
	split the group, everyone would have to read all the groups anyways,
	there'd be a *lot* of crossposting, and the group doesn't get that
	much traffic anyways.

	If you're feeling snowed under, poke around your site, and figure
	out how to use kill files, if you have them, to filter out articles
	on subjects you're not interested in.

------------------------------------------------------------------------
>>>> Other photo informational sheets, and mailing lists
------------------------------------------------------------------------

	These are posted to rec.photo by the indicated people (when
I know 'em -- please let me know of any mistakes or missing info). This
should not be taken as license to mail these people for copies! Please
wait a while for a copy to be posted before trying other routes.


	- Nikon FAQ sheet (monthly posting) -- (kjm@cnmss.treydev.unisys.com)
	- Camera Feature List(s) --  glporter@zeus.calpoly.edu (Glen Porter)
	- Mail-order house review list -- blondin@druhi.ATT.COM (BlondinDJ)


These are the photographic mailing lists I know of:


	Brian Reid runs a mailing list of people who use Leicas and other
	rangefinder cameras. If you'd like to be on it, send mail to:
        leica-users-request@mejac.palo-alto.ca.us
                or
        decwrl!mejac!leica-users-request, if you can't do "@" addressing.


	Hassleblad / Medium Format Digest. Moderated. Seems to be generating
	a digest every day or two(?). Send mail to cmcdowel@ecn.purdue.edu,
	clearly indicating your email address in the body of the letter.


	Mailing list for Bronica S, EC, and EC/TL users.  This list
	is dedicated to these models since many of the parts are
	interchangeable. The purpose is to create a forum that is the
	most likely place to get answers to your questions about these
	cameras.  Subscribe by sending a note to:

	bronysaur-request@post.royalroads.ca


	The stereo mailing list seems to have faded away.

------------------------------------------------------------------------
>>>> A short lexicon of terms
------------------------------------------------------------------------


f-stop
	The ratio of focal length to aperture diameter (actually,
	'entrance pupil' diameter, which is not quite the same).
	Any two lenses set at the same f-stop will allow the same
	amount of light to pass through them (aside from minor
	differences in light losses in the lens). Smaller numbers
	mean more light.

ISO/ASA, Film speed
	The rated speed of the film, as determined by a published
	and somewhat technical standard. Higher numbers indicate
	that the film in question requires less exposure. Some films
	seem to perform better when used at speeds different from the
	manufacturer recommendation, however.

EI, Exposure index
	The film speed at which the photographer chooses to shoot
	the film. Often the same as the ISO/ASA of the film.

EV, Exposure Value
	A measure of total exposure given the film. 1 sec at f/1.0
	is EV 0, as is any other equivalent f-stop/shutter speed
	combination (2 sec at f/1.4, 4 sec at f/2.0). EV 1 is one stop
	*less* exposure (e.g. 1 sec at f/1.4), EV -1 is one
	stop more, and so on.

GN, guide number
	Power rating for flash. Given a film speed (An EI, in
	fact), to compute the correct f-stop for exposure,
	divide the GN by the subject distance. NOTE: this implies
	that you need the correct units for subject distance, both
	feet and meters are commonly used. GN's for a flash
	are usually given as 'GN 140 in meters at ISO 100'.


------------------------------------------------------------------------
>>>> Some useful phone numbers
------------------------------------------------------------------------

[I've only tried some of these, and would especially welcome any
	additions and/or corrections! - Andrew]

800 number phone # directory system: 1-800-555-1212

Canon:
	800-828-4040
	NY 516-488-6700 (east coast)
	CA 714-769-6000 (west coast)
Minolta Consumer Relations
	CA  714-895-6633 x101  Douglas Dodge or Bill Suarez
	NJ  201-825-4000
Minox:
	516-437-7837
Nikon:
	800-NIKON-US, 800-645-6687 (general info/customer support)
	800-645-6635 (new product information)
	213-516-7124 (parts depot)
Olympus:
	NY  516-364-3000
	NJ  800-221-3000  dealer listings, manuals, literature
Yashica:
	201-560-0060 (USA main office)
	312-250-0591 (midwest USA office)
	818-247-2140 (western USA office)
	416-671-4300 (Kyocera Canada)
	(040)25 15 07 0 (Yashica Kyocera Germany)
	(01)720 34 34 (Yashica Switzerland)
	283-4244 (Yashica do Brasil Industria e Comercio Ltda.)
	(03)797-4631 (Yashica Japan)
Calumet:
	800-CALUMET
Kodak Information:
	800-242-2424
Ilford Information:
	800-535-9205
Ilford technical support:
	201-265-6000
Pentax:
	303-799-8000
Fuji Customer Service:
	East Coast: 800-279-4419 (??)
	West Coast: 800-326-0800 ext. 4223
Polaroid Customer Service:
	800-225-1618
Light Impressions (dealer in archival products)
	800-828-6216
University Products (dealer in archival products)
	800-828-6216
Lightworks (source of photographic chemistry)
	800-776-9678
Bostick & Sullivan (platinum printing and other exotic chemistry)
	818-785-4130

------------------------------------------------------------------------
>>>> Some miscellaneous questions
------------------------------------------------------------------------

Will airport X-ray machines damage my film?

	Reports vary. Some machines will, others won't. High speed
	film (ISO 1000, up) is certainly at risk. Ask for a hand search,
	but you may not get one. Lead bags may help. Don't worry
	overmuch about ordinary film.

How do I take pictures of TV screens/monitors?

	Use a tripod and slow shutter speeds. Use a shutter speed of 1/30
	of a second or slower (i.e. 1/15, 1/8 etc..) The longer you can 
	make the exposure, the better. Bracket exposures a stop or two
	each way. Longer lenses will help compensate for curvature of the
	screen. Darken the room to help eliminate glare from the screen.
	Do everything you can to align your camera with the screen. It is
	very easy to take crooked pictures!

	See Kodak publication AC-10, as well.

How do I take pictures of fireworks?


	You will need a tripod. The idea is to leave the shutter open
	long enough to catch a few bursts. As with flash photography,
	exposure is determined only by aperture. Try F-stop = square-
	root of film speed, as a guideline. With ISO 100 film, try an
	f-stop around f/11, and an exposure of 3-6 seconds, for example.
	Use the widest angle lens you have, 50mm is a little too narrow
	on 35mm camera. Ask your photofinisher to print the sky black,
	lest the print be 'compensated' and come out gray.

Help! I over/under exposed a roll of film!

	Color print film overexposed by 1 or 2 stops can be processed
	normally. It's somewhat more sensitive to underexposure. Slide
	film is not nearly as easy-going. Films can be push or pull
	processed, to compensate (to some extent) for under or over
	exposure. Prices for this service vary from a couple bucks a
	roll on up. Shop around.

My prints look all funny! What can I do?

	Look at the negatives, to see if they're the problem. If a
	huge blotch appears on the print but not on the neg, or if
	there's no detail in grandma's dress in the print, but you
	can clearly see it in the neg, then get a reprint (and ask for
	it to be done free!). Printing problems are common, and can
	be corrected by re-doing the print right.

How do I get film leaders out of film cans?

	If your camera doesn't let you rewind film in such a way as to
	leave the leader out, your best bet seems to be to stop by your
	local photo store and get the little tool they sell for
	extracting leaders from cans. These apparently work really well.
	Some people can fool an power-rewind by popping the back open
	as they hear the film snap off the takeup spool.

The <X> in/on my camera is dirty, how do I clean it?

	If it's the mirror, or something in the viewfinder, don't
	worry about it (it doesn't effect image quality). If it's the
	lens, get some lens cleaner and tissue, and follow the
	instructions. Don't worry about minor smudges or specks of
	dust on or inside the lens, they won't have any serious
	impact. Think before scrubbing!

Do I need a 'circular' polarizer, and what is one, anyway?

	Circular polarizers are just like regular polarizers, but
	have an additional optical element to stir the light up
	after the filter has done its thing. This stirring keeps
	autofocus mechanisms and some light-metering mechanisms from
	getting confused by polarised light. If the manual says you need
	to use one, you likely do.

Do I need a UV/skylight filter on my lens?

	This is a tough call. Such a filter will protect the lens, and
	will alter your images slightly in the positive ways advertised.
	They will also degrade image sharpness slightly, and contribute
	to flare (you get two more air-glass surfaces in the light path).

What about teleconverters?

	They degrade image quality noticeably, yes. The best image
	quality is obtained from a lens of the appropriate length.
	Next is a lens + *matched* teleconverter (i.e. a teleconverter
	designed especially for the lens, or lens family), followed by
	a fixed focal length lens with a non-matched teleconverter.
	Using that $90 teleconverter on your 3rd party 70-200mm
	zoom lens will make rotten pictures. Using that Nikon 300mm
	lens with the matched 1.4X teleconverter will make nice
	pictures, you'll probably need a loupe to see degradation
	from a real 400mm lens.

What about mirror lenses?

	Mirror lenses are small and cheap and have long focal lengths.
	They also tend to have fixed-size apertures (and slow, typically
	f8 or worse), so you can adjust exposure only with shutter speed
	or filters to reduce light. Finally, they render out-of-focus
	highlights as fuzzy donuts rather than fuzzy dots, which some
	find objectionable.

What's the Zone System?

	It's a system of light-metering combined with development
	tailored to each exposure, to produce as good a negative as
	possible. It was developed by the famous photographer Ansel
	Adams.

Is there a Zone System for color photography?

	Not really. You can use the ideas to get your exposures
	'right', but development controls are out, since altering
	development makes nasty color shifts. There are various
	unsatisfactory systems published, but this is the short form.

What's the sunny 16 rule?

	For taking pictures of objects brightly lit by the sun, in the
	absence of a better guess, expose the film at f/16, with a
	shutter speed of 1/<film ISO> (or equivalent). I.E. ISO 400
	film yields 1/400 sec at f/16, 1/800 sec at f/11 etc.. Choose
	the nearest shutter speed your camera has (1/500 and 1/1000
	in the example, for many cameras).

How do I take a picture of the moon?

	Well, the moon is brightly lit by the sun, so use the sunny 16
	rule! Before you say this is crazy, note that it doesn't matter
	how far away Aunt Martha is, as long as she's well lit by the sun,
	right? The moon's a bit farther out.. Often, you want the moon a
	little overexposed (it's a bright white thing, you know) so
	the 'looney 11' rule has been suggested. Use f/11 and 1/ISO
	shutter speed. Also, you really will want a very long lens, lest
	you wind up with a small white dot. The longer the better, really.

How about some general guesstimated exposure guidelines?

	Ok! This is a table of compensations, in stops, from the sunny 16
	rule. E.G. For heavy rain, use 4 stops more exposure, for a backlit
	subject in hazy sun, use 1 + 1.5 to 2 stops more.

	I stole this table verbatim from (faust@bagels.enet.dec.com):

	Sunny 16 variations		Lighting correction
	Bright sun      0		Backlit subject         +1-1/2 to +2
	Hazy sun        +1		Sidelight Subject       +1/2 to +1
	Light clouds    +2		  (-1/2 under hazy conditions, -0
	Overcast        +3		  under overcast or shade conditions)
	Heavy rain      +4
	Dense Shade     +6

What's a grey card, and what's it good for?

	A grey card is, well, a grey cardboard card. It's a specific
	shade of grey, 18% reflectance (correct term?), that's visually
	about the middle between black and white. More usefully, it's
	also the 'average' tone camera meters aim at. Taking a meter
	reading off of a grey card held next to your subject gives
	you the exposure that will render the grey card the right tone
	on film -- and as a corollary, should render a black subject
	black and a white subject white. Metering off the white subject
	will render it 18% grey, you see, which isn't always what you
	want.

------------------------------------------------------------------------
>>>> Equipment - brands, purchasing and quality
------------------------------------------------------------------------

	This section is full of probably unfair generalisations, and
exceptions to the things said abound. The author has tried to write short
rules of thumb to be taken with a grain of salt, the most important
of which is that you tend to get what you pay for. Expensive things
tend to be better than cheaper things. Do not expect the $30 Pakina
special to perform as well as the Canon!

	The term 'Big Name Manufacturers' is used below to avoid writing
long lists of manufacturers of things photographic. By way of example
only, Nikon and Canon are Big Name makers of cameras, Kodak and Fuji
are Big Name film manufacturers.

What's a good cheap camera?

	There are lots of them. Go to your local dealer, and spend
	some time talking and trying things out. Find out what
	features *you* want. Be prepared to take some time to handle
	equipment.

Are the New York mailorder places good?

	If you know exactly what you want before you order, they're
	generally ok. Don't let them pressure you into buying extra
	stuff. B&H, Camera World of Oregon, and Adorama are places with
	good reputations. Avoid Cambridge Camera Exchange at all costs.

Who makes the best lenses?

	The Big Name manufacturers all make make marvelous lenses. Arguing
	about lens quality is a waste of time, since the actual differences
	are not really great. If you want sharper images, use a monopod or
	tripod, or go to a larger film format.

Are Sigma/Vivitar/Tokina/etc lenses any good?

	In general, they are not as good as those made by the Big Name
	Manufacturers -- this should not be surprising, since they are in
	general cheaper. The modestly priced zoom lenses are likely fine
	for snapshots. Durability of these lenses is reputed to be lower
	than the Big Name lenses.

Who makes the best cameras?

	See 'Who makes the best lenses'!

Who makes the best film?

	That depends on your application. The standard color print
	films are probably fine for most normal applications. Is
	there a problem with the film(s) you have used in the past?
	If not, stick with them. All the Big Name manufacturers make
	decent films, and there are very few bad films.

	Some color print films:
	Under lights of mixed color or fluorescents - Fuji Reala.
	High resolution -  Ektar 25.
	High speed - Ektapress 1600 (and other Ektapresses)
	Low contrast - Kodak VPS VPH
	Wide exposure latitude - Gold 100.

	Some slide films:
	Good archival qualities - Kodachrome.
	Saturated (bright) colors - Fuji Velvia.

I have a chance to buy <X> for $<Y>, is it a good deal?

	Get a copy of Shutterbug, and look around in the various
	advertisements for an idea of current prices. If it might be
	a 'classic' of some sort, look at McKeown's or McBroom's
	guides (my local photo shop has a copy they let me look at,
	your local library may well have copies as well).
Newsgroups: rec.photo