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<title>Rec.Photo.Darkoom Frequently Asked Questions
<author><url name="Cees de Groot" url="mailto:cg@cdegroot.com">

<toc>

<sect>Introduction
<p>
Welcome to the <htmlurl name="rec.photo.darkroom" url="news:rec.photo.darkroom">
FAQ. You should read this document before posting to rec.photo.darkroom in
order to prevent you from embarrassments, such as asking questions that
are answered in this FAQ. This version of the FAQ is labelled
<tt>$Revision: 1.10 $</tt>.

<p>
This FAQ is available on the World Wide Web, in several formats:
<itemize>
<item><url url="http://www.cdegroot.com/photo/darkroom-faq.html" name="HTML format">
<item><url url="http://www.cdegroot.com/photo/darkroom-faq.sgml" name="SGML format">
<item><url url="http://www.cdegroot.com/photo/darkroom-faq.txt"  name="plain text">
<item><url url="http://www.cdegroot.com/photo/darkroom-faq.ps"   name="PostScript">
</itemize>
If you have any problems, suggestions, or questions,
please contact the maintainer, 
<url url="mailto:cg@pobox.com" name="Cees de Groot">.

<sect1>I don't have access to the Web
<p>
``You're pointing to Websites everywhere, but I don't have access to the
WWW.'' Sorry, but I think that you are out of luck. To put it bluntly, I
feel that if you can afford to put time and money into photography, you
should be able to put time and money into the greatest information
resource on photography - the Web. Furthermore, people <em/expect/
you to have access to the Web, so they will respond irritated if you
ask questions on the newsgroup that are one click away from this FAQ.

So do yourself a favour, and get a decent Internet account.

<sect1>Acknowledgements
<p>
Jean-David Beyer for typing in the quote from 
Kodak's T-Max datasheet :-). 
<url name="Tom Reed" url="mailto:treed@omicron.csustan.edu"> for suggesting
the parts on VC paper (and supplying me with the table of filtration values).

<sect1>Disclaimer, copyright
<p>
I've done everything in my power and limited time to make sure that the 
information in this FAQ is correct. However, neither I nor any contributors
can be held responsible for the results of acting on this information or
for any damages resulting from using the information in this document in any
way.

Copyright (C)1997 by Cees A. de Groot. This document may be distributed
and reproduced without permission provided that it stays intact, including
this copyright notice. 

(The copyright has my name on it because somebody has to own
the copyright; however, I want stress the fact that the actual
intellectual ``owner'' of this document is the collective readership
of rec.photo.darkroom.)

<sect>General information
<p>
<sect1>What is rec.photo.darkroom all about?
<p>
Darkroom work. In the broadest sense. There are people here trying to get
started with developing 35mm film, people busy with alternative processes,
professional darkroom workers, etcetera. There are many many topics which
are discussed: materials, technique, equipment, etcetera. There are some
questions, however, which are better discussed in other groups, like the
quality of films (<htmlurl name="rec.photo.film+labs"
url="news:rec.photo.film+labs">) and buying/selling equipment
(<htmlurl name="rec.photo.marketplace" url="news:rec.photo.marketplace">).

Here's the newsgroups line and the charter of rec.photo.darkroom:
<quote>
<bf/rec.photo.darkroom/ Developing, printing and other darkroom issues
<p>
This newsgroup will contain postings related to all aspects of photographic
darkroom use. As such it will cover subjects such as the developing of
slide and negative film, photographic printing from negatives and slides,
photographic toning processes and alternative chemistry. This newsgroup
specifically does *NOT* permit the posting of commercial advertisments for
products or services, even if they are related to photography.
</quote>
By the way, all the charters for the rec.photo groups are available
on <htmlurl name="Photo.net" url="http://bobatkins.photo.net/info/charter.htm">.
Read them, before you post...

<sect1>What is The Link?
<p>
I'm going to introduce a new saying on the rec.photo newsgroups: <em>
Use The Link, Luke</em> ;-). 

The Link is <url name="The Guide to rec.photo FAQs" 
url="http://www4.ncsu.edu/unity/users/j/jnweg/faq44.htm">, and is simply
a huge collection of pointers to other places. If you have any interest
in photography, you should definitely bookmark this place.

<sect1>Your Mileage May Vary?
<p>
``YMMV'' is a well-known Usenetism to indicate that what works for me, may
not work for you. This is especially true in photography. Although all 
photographic processes are subject to the laws of physics and chemistry,
there is such a large variation of factors you need to take into account
that it is impossible to say how something will work out exactly in
somebody else's darkroom. Add to that personal preferences - what I call
fine grain is horrible, golf-ball grain to the next guy - and you'll
understand that the only way to find out is to experiment.

Especially questions containing the words ``will ... make a difference?''
are subject to this: probably, somebody with a well-equipped lab having
access to advanced measuring instruments will always find a difference. But
this does not matter. What matters, is whether <em/you/ will see a 
difference. So, rather than ask the Net, you might as well see for yourself,
because you're likely to get vague answers anyway.

Test And Experiment, you can only learn from it.

<sect>The darkroom
<p>
<sect1>How do I build a darkroom?
<p>
There's an awful lot to say here, and it is all very dependent on what kind
of space (big/small, permanent/nonpermanent) you have. Kodak has a lot of
good, sound advice on darkroom building, and I'm aware of one links
covering the topic:
<itemize>
<item><htmlurl name="http://www.darkroomsource.com"
               url="http://www.darkroomsource.com">
</itemize>


<sect1>Can I use tapwater for ...?
<p>
Generally speaking: yes you can. The short answer comes from
<url name="David Manzi" url="mailto:dman3@mediaone.net">, I quote:
<verb>
Could you use it from a tap?
Yes you could, you little sap!
Could you use it for a mix?
Sure you could, without a fix!
Can I use it for a wash?
Absolutely, let is slosh!
But what about photo-flo?
Ooo I'm sorry, that's a no.
</verb>

The general consensus is that normal tapwater doesn't contain any chemicals
in high enough concentrations to influence photographic processes. This is
assuming we are talking about water from a water company - well water may
very well be unsuitable for darkroom work. The only exception is the final
rinse with wetting agent (Photo Flo), where hard water may still leave
drying marks; here it makes sense to use distilled water, water from an
air dehumidifier, or bottled water (if it is soft enough). 

This is only a general consensus, people have been complaining about their
tap water's fitness for darkroom work. If you feel uncertain, you might
want to consult others in the area (minilabs), your water company, etcetera.

<sect1>How do I store chemicals?
<p>
A discussion that is coming up over and over again is what kind of bottles
are best used to store chemicals. The best stuff, but you already knew
that, is dark brown glass bottles with stops made for keeping chemicals
in and air out. Glass doesn't let air through and is easy to clean, and
these are the two most important considerations (brown glass also doesn't
let light in that could harm your chemicals). These bottles are also the
most expensive ones, so you might want to use them only for chemicals
that oxidize easily, like developer. 

Plastics are permeable to air, and not as easy to clean (chemicals can
and will be absorbed by plastic and it'll never get out). The cleaning
part is solved mostly by only using any given container for a single type
of solution. How much oxygen can get to your chemicals depends on the
type of plastic and its thickness (the thicker, the better). The best
solution is metalized plastic, then PETE, HDPE, LDPE, PP, PVC, PS and
last and worst Teflon. Here's an overview of plastics names, the numbers
that appear inside the "recycling triangle" on containers from these
materials, and what they're often used for:

<table>
<tabular ca="rll">
1 | Polyethylene terepthalate (PETE) | soft drink bottles @
2 | High Density Polyethylene (HDPE) | milk, juice and laundry product bottles,  Nalgene laboratory ware and bottles  @
3 | Polyvinyl Chloride (PVC)  | cooking oil, water, vinegar and bleach bottles @
4 | Low Density Polyethylene (LDPE) |  bags, margarine and ice containers @
5 | Polypropylene (PP) | yogurt cups and ketchup and syrup bottles @
6 | Polystyrene (PS) | clear: salad containers, disposable cups; expanded: insulating food containers @
- |  (Poly)tetrafluoroethylene ((P)TFE) | Dupont Trademark "Teflon"; laboratory and environmental sampling containers @
</tabular>
<caption></caption>
</table>
(table and most of the information in this section from a posting by
<url name="Marc Hult" url="mailto:hult@cinternet.net"> in 
<htmlurl name="rec.photo.darkroom" url="news:rec.photo.darkroom">,
Message ID &lt;35545554.231656@news.one.net>).

<sect1>How do I remove water marks?
<p>
A recipe by <url name="Richard Knoppow" url="mailto:dickburk@ix.netcom.com">,
found in rec.photo.darkoom:

"Try the following.  Soak the film for a few minutes in plain water,
then treat it for a couple of minutes in stop bath. Swab the surface
gently with cotton swabs.  If there is anything left treat it with a
wash aid like Kodak Hypo Clearing Agent for a minute or two and again
try swabbing.  This should remove any deposits left by the Photo-Flo.
Then wash the film for five minutes and treat in a mixture of
distilled water with about one ounce per quart of rubbing alcohol
added (Mike Gudzinowicz correct this if wrong) and about half the
amount of Photo-Flow recommended by Kodak.  Hang it up to dry without
further swabbing."

<sect1>How do I get rid of my old chemicals?
<p>
This depends on your local circumstances. If you're connected to a sewage 
treatment plant, just down the drain with it. The stuff you produce day by
day on the toilet puts more load on the system than the relatively small
amounts of waste chemicals you collect in your darkroom. It's more hazardous,
too, to collect and store large amounts of processed chemicals in order to 
bring them to a depot (if you have one in your area). If you're unsure
whether you're allowed to do this (regulations may vary), contact the
guys who process your water - I'm sure they'll be more than happy to 
give advice.

People have reported no problems dumping chemicals into their septic
tank system, although some take the precaution to dump them together with
large volumes of water, eg. when the washing machine pumps its water out. If
you are not sure your septic tank will survive photochemicals, contact
your dealer (at the very least, you've got somebody to sue :-)).

If you cannot or don't want to dump chemicals down the drain, an often-heard
advise is to collect it in a large cannister which you leave open in order
to have the water evaporate. You can then regularly collect the crystals
from the cannister and get rid of them in whatever way you get rid of other
dry chemical waste (which all depends on local regulations). Take precautions
against spilling or leakage, like storing the cannister in a tray that can
hold the volume of fluid in the cannister.

Note that all these rules apply to hobby darkrooms only. If you're a 
professional, you should contact your local environmental authority and
talk to them; most places have strict rules about chemical
storage and disposal for professionally-run darkrooms and photolabs.


<sect1>What's the difference between the various enlarger types?
<p>
There are two main types of enlargers: diffusion and condensor enlargers. The
difference is in the type of light that hits the film: a diffusion enlarger
has a light mixing chamber and/or a diffuse translucent panel in order to
shed an evenly distributed, diffuse light onto the negative. A condensor
enlarger uses one or more lens elements in order to produce a colliminated
light beam focused on the negative. 

You cannot say that one type is better than the other - a lot of photographers
have taken foot in one camp and defend their type of enlarger in an almost
religous way, but you will be able to produce good prints with both. 

There are
some objective differences due to the nature of the light:
<itemize>
<item>The specular light from the condensor enlarger tends to enhance dust, 
  etcetera, on the negative. You need to be more careful, but it's not a 
  very big deal. A condensor enlarger also tends to show more grain in
  the print, but see the next point. On the other hand, the images are
  a bit sharper, which makes them especially popular for small formats
  like 35mm.
<item>The specular light also gives higher contrast. This is hard to 
  explain in just a few words, but it's a well-known effect discovered by
  a Mr. Callier in the early days of this century: specular light gives 
  higher density readings than diffuse light, and the ratio between these
  density readings is called the Callier Coefficient. I won't go into the
  details, but it means you need to shorten your development times in order
  to correct for this effect. Shorter development gives smaller grains and
  this offsets the higher grain from the previous point.
<item>Again due to the Callier effect, you will have a difference in contrast
  between contact prints and enlarged prints with a condensor enlarger:
  contact prints always show the diffuse densities in your negative,
  condensor enlarged prints show the higher specular densities. If you
  make a contact sheet, you will usually need a higher paper grade for
  this contact sheet in order to see the effect you'll get when enlarging
  the negatives. This is not a very big deal - you can match paper grades
  quite easily (it's normally one grade difference), and for good prints
  the grade indicated by a contact print is just a starting point, anyway
  (Ansel Adams used a very soft grade for his contact sheets in order to
  get maximal information, thus completely bypassing this problem).
</itemize>

<sect>Film processing
<p>
<sect1>How do I process...
<p>
Did you check the manufacturer information? I don't mean the stuff printed
on the inside of the box, but the full information readily available
on the web or even as hardcopy? When starting with a new film/developer
combination, make sure that you get and read the manufacturer datasheets
of both developer and film first - most of the manufacturers have
datasheets available on the Web:
<itemize>
<item><url name="Kodak" url="http://www.kodak.com/ciHome/products/L1/">,
  or call 1-800-242-2424 ext. 19 if you are in the US;
<item><url name="Agfa"  url="http://www.agfaphoto.com/products/index.html">;
<item><url name="Ilford" url="http://www.ilford.com/html/us_english/homeng.html">;
<item><url name="Fuji" url="http://www.fujifilm.com/">.
</itemize>
Then, there is an incredible amount of information about processing film
on the web maintained by individuals. A (very) short list:
<itemize>
<item><url name="Photo Source"
  url="http://www.digitaltruth.com/">, with
  the Massive &bw; Dev Chart, a gigantic list of development times for
  a lot of film/developer combinations.
</itemize>
and of course: Use The Link, Luke.

<sect1>My Kodak Tmax film comes out purple - what happened?
<p>
Tmax (and other T-grain films like Ilford Delta) have sensitizing dies
incorporated into the emulsion that cannot be washed out very easily. If
you don't follow processing instructions carefully, this sensitizing
dye gives a purple/pink/magenta hue. According to Kodak, a slight hue
doesn't influence printing, but if the color is stronger, it adds
to base+fog density.

First of all, get Kodak datasheet F-32. Via the Web (see above) or from
your photographic dealer. If you read the instructions carefully and
follow them, you won't have any problems. In a few words, you need to
dump your fixer earlier (because these emulsions exhaust them faster),
agitate vigourously when fixing,
wash a bit longer, and use Hypo Clearing Agent. As this is FAQ number
one on the group, I'll just quote F-32:
<quote>
"Fix at 65 to 75F (18C to 24C) for 3 to 5 minutes with vigorous agitation
in KODAK Rapid Fixer. Be sure to agitate the film frequently during fixing.
<p>
"Note: To keep fixing times as short as possible, we strongly recommend using
KODAK Rapid Fixer. If you use another fixer, such as KODAK Fixer or KODAFIX
solution, fix for 5 to 10 minutes or twice the time it takes for the film to
clear. You can check the film for clearing after 3 minutes in KODAK Rapid
Fixer or 5 minutes in KODAK Fixer or KODAFIX Solution.
<p>
"Important: Your fixer will be exhausted more rapidly with these films than
with other films. If your negatives show a magenta (pink) stain after fixing,
your fixer may be near exhaustion, or you may not have used a long enough time.
If the stain is slight, it will not affect negative contrast or printing times.
If pronounced and irregular over the film surface, refix the film in fresh
fixer.
<p>
"Wash for 20 to 30 minutes in running water at 65F to 75F (18C to 24C) with
a flow ratre that provides at least one complete change of water in 5 minutes.
You can wash long rolls on the processing reel. To save time and conserve water,
use KODAK Hypo Clearing Agent."
</quote>
The Ilford datasheets for Delta films have similar instructions.  If you
have films with these residual dies in them, re-fixing followed by a long
wash may help.

<sect>What's the advantage of diluting developer?
<p>
When you dilute developer, you change the chemical characteristics of the
various components. The two effects most cited are that you get better
sharpness, but at the same time slightly larger grain - both caused by the
suppression of silver solvent action. You also can gain a bit more speed,
and because of the extended developing times, it is easier to get even
and consistent development. Dilute developer makes it economical to use it
one-shot (throw it away after usage), which further adds to consistency.

In howfar the effects of dilute developer are visible, depends on the
film/developer combination. When starting out with a new
combo, test various dilutions and see whether you can make out
any differences. Use what you like best.

<sect>Printing
<p>
<sect1>Resin-coated of Fiber-based paper?
<p>
Which one you will use depends on a lot of things. First, the facts:
<itemize>
<item> FB paper has proven archival qualities (given proper processing). That's
  why collectors, musea, etc. often insist on FB.
<item> RC paper has shown good keeping qualities in accellerated aging tests.
  If it is just for yourself, friends and family, I think you can rest
  assured that it will keep the rest of your life. But, until RC paper has
  been on the market for another 100 years, it's not called archival.
<item> RC paper is much easier to process. It is especially easy
  to wash and dry, and it won't curl.
<item> FB paper is less sensitive to the temperatures in a dry-mount press.
<item> FB paper can be kept wet for a very long time, whereas with RC
  paper, you risk separation of the layers.
</itemize>
Then the opinions: there are people who simply like the look and feel 
of FB paper better. You should decide that for yourself, of course. Invest
in a small package of both, that will give you a better answer than 
asking the newsgroup.

<sect1>Can I use brand A VC filters on brand B paper?
<p>
Yes, but there might be small differences in the
grades you get. However, a #2 filter will always give a softer result
as a #3 filter, no matter on which paper you use it.

My humble opinion: the subtle differences of mixing up
filters and papers are probably smaller than the differences introduced
by the fact that you probably use another developer, enlarger and
darkroom than the factory test facility. So you need to test anyway (I
test by contact printing a step tablet).

<sect1>I have a color head, can I print on VC paper?
<p>
Yes, you can. Again, get the datasheets of the paper - manufacturers of
VC paper normally have color filtration values for the various grades. A
starting point:
<table>
<tabular ca="ll">
Grade 2    | 45M/9Y @
Grade 2.5 | 65M/12Y @
Grade 3 | 95M/15Y @
Grade 3.5 | 120M/20Y @
Grade 4 | 200M/30Y @
Grade 5+ | 200M @
</tabular>
</table>

<sect1>Can I print color negatives on black-and-white paper?
<p>
Yes, you can. Normal &bw; paper, however, is not panchromatic - it
only responds to a narrow band of wavelengths of light. Graded paper just
responds to blue light, and variable contrast paper responds to
blue and green light (but the amounts of blue and green light influence
the gradation of the paper). Generally speaking, printing color negs
on &bw; paper won't give natural-looking results.

Kodak has a panchromatic paper, Panalure, available in 3 grades. If you
want to get good results printing from color negatives, you should use
this paper.

Of course, using normal &bw; paper <em/can/ give interesting effects, 
comparable with using orthochromatic film - experiment!

</article>
