Depends on what you're using. But my answer is going to be no. The
cheapest method is usually to buy bigger packages/bottles of pre mixed
chemicals. The bigger sizes aimed at commerical labs are much cheaper then
the smaller sizes aimed at home users.  

   OTOH you can go to say:
   
   www.jdphotochem.com
   
   And work out the costs yourself. The cheapest way is to buy the big
packages of chemicals. Some will get used in almost every thing [sodium
sulfite] but even the stuff you only use a little of will keep quite awhile.

    Nick

Can be; depends on the chemicals. Some stuff like lye (Sodium Hydroxide),
Sodium Carbonate, Borax I can get at the grocery store.

I don't think so. Plus I'm not sure what you mean by the
flexibility, Phil. Generally, I mix my own only when it
benifits the results I want to achieve. Example: mixing
my own print developer (which I have done) was never as
efficacious IMO than using standard packaged Dektol.

I had a professor in college who insisted Amidol was
artistically "better" (for him) than dektol. I never
found this to show in my own prints and quit mixing
it. Much cheaper to use the school lab's premixed
Dektol.

It really depends on what you want/need, and/or are
wanting to achieve. I mix my own negative developers
but only to a point. Example: if I'm developing Tech
Pan I use my own pyro-phenidone mixture because I think
I get better curves than with packaged Technidol or
TD-3. If I'm using T-max I prefer Rodinal, HC110,
or some other commercial developer.

I would say that rather than 'flexable', you rather
should be aware of just what results you expect when
you mix your own. BTW, developer should IMO always be
used one shot, but I never any chemistry (especially
fixer) to exhaustion. As soon as fixer shows any
concentration of silver compounds (fixer test) I
discard it or use it for work prints. Likewise I
never use stop to exhaustion.

I consider rapid fix, acetic acid, and hypo clear to
be relatively cheap.

The cheapest reliable film developer that I know of is HC-110 mixed from the
syrupy concentrate.  If you take only the amount of concentrate you need for
one-shot use, the rest of it will keep for years.  See:

www.covingtoninnovations.com/hc110

As for mixing your own, D-23 has been recommended as especially simple.  I
don't know how economical it is.  Try to get a formula measured in spoonfuls
rather than grams (there are people who have worked it out that way).

I use self-mixed film developers exclusively. While I do this for
flexibility (I can tweak my developers as long as I like it), this is
cheaper than buying premixed developers. One example: 1 liter D76H
(for all practical purposes identical to D76) costs about 35 Euro-Cent.
One liter Perceptol-lookalike (5g Metol, 100g Sodiumsulfite, 33g NaCl,
1g boric acid, 1l water) costs about 40 Euro-Cent. Weighting takes about
5min for one batch.

My results with these homemade developers are excellent, I don't care
how long they will keep... at this prices, the remains get thrown away
after one developing session, and of course I use them one-shot.

Martin

There isn't a simple answer. It depends on how much you use. For
large volumes it may be cheaper. If you search Google for "photographic
chemicals" you will find a number of sources. Check the prices. Then
calculate what it costs to mix some common processing solutions which
have published formulas. Sometimes you will wind up paying hazardous
materials shipping charges, these make otherwise cheap chemicals
expensive and must be taken into account.
Pushing stop bath and fixer to the limit is not good practice.
Stop bath will become neutralized by the developer fairly rapidly
especially when printing. This is one solution that I can say flatly is
cheaper to mix yourself. A liter of glacial acetic acid will make about
65 liters of stop bath, so is much cheaper than buying 28% or even
Kodak Indicator Stop Bath, which is about double this concentration.
Fixing baths should not be overused because the resulting images
will not be permanent. The most economical way to do fixing is to use
two successive baths. The capacity is four to ten times that of a
single bath.
For large enough volumes of film a replenished system is very
economical and will produce very consistent results if managed right.
Some developers are their own replenishers, for instance Kodak T-Max
RS.
Again, it depends on how much work you do.
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com

It depends. Some chemicals are cheap and last a long time. Others are
expensive and oxidize rapidly. It is generally more advisable to mix up
only those developers that use metol, hydroquinone, sodium carbonate,
borax, sodium sulphite, potassium bromide, and sodium bisulphite. These
keep fairly well.

Glycin oxisizes repidly, and phenidone is hard to measure in very small
quantities. It's likely to go bad before you use it all, and because
it's used in such small quantirties, it's hard to measure consistently
in small batches.
So, making up D-76, D-23/D-25, D-72, 55-D, 54-D, 56-D, etc are easy.

I have been making my own chemicals now for about 7+ years.  The
economic savings are definitely there.  Developing a roll of film costs
pennies only.  I made up a two part batch of PMK 3 1/2 years ago.  It is
still good and I have some left.  I use a lot of D-76 as well.  That
will keep well if refrigerated, but you only have 6 months to a year on
an unopened, filled, refrigerated container.

Stop bath lasts for years, assuming you use it (which I do only
occasionally now).  Fixer is cheap if the sodium thiosulfate or ammonium
thiosulfate are bought in large enough quantities.  I buy 10 lb of the
former or a gallon of the latter.   The raw chemicals of any in this
paragraph do not deteriorate for a long time.

In addition to cost savings there is flexibility.  You want D-23 not
D-76?  No problem.  You want to experiment with the amount of potassium
bromide?  No problem.  You want absolutely fresh chemistry?  Make only
enough to last a short period of time.

I even make color chemistry (C-41 and RA-4).  As this chemistry (the
developers that is - the bleach fixes last until exhausted)  has a much
shorter life span than B&W chemistry, I make only enough for sort term
needs.  So I always have fresh developers.

Buy enough of the raw chemicals and you will not have to resupply for a
couple of years.

Francis A. Miniter

I wouldn't use any chemistry to exhaustion, stop is quite cheap,
especially in it's generic forms, Acetic Acid, and vinager.  It's not
affected (much) by oxidation, so don't buy small bottles.  Buy it in
larger amounts, the price per ml goes down quite quickly.  Fixer is the
same, in a tightly capped bottle, it's not affected much by air, so
instead of buying 500ml, buy 20L at a time......

The only thing that is affected by air is developers, a few solutions:

1) Buy the 5L pack, mix as stock, and put it in one of those wine boxes,
they have a mylar bladder inside, so your concentrate is not exposed to
air.  If it works for wine, it will work for developer.  The box
protects the bladder from damage, and the spigot makes it easy to
control the amounts.  Typically the mylar is bound to aluminum foil or
other similar not-reactive materials.

2) You can mix up stock, put it in 1L glass or PET bottles, fill right
to the top, use a rubber stopper instead of the plastic cap, or seal the
top with wax, so the cap doesn't leak air.  Keep sealed until needed.
You can use 2 500ml bottles, so that only 500ml of stock is open to the
air at one time.

3) Displace air with something else, typically an inert gas, like
nitrogen, you fill the top of the bottle with the gas, before securing
the cap.  This of course, means you need a tank of the stuff, in your
darkroom.

RE:

Much more so. For the most part powders and concentrates
will keep many years.

I'm in the dark off, off, off, and on, and off and on and on,
and off; well you get the idea. So, I had no choice but to
compound all my own chemistry; a big savings and real
fresh chemistry when needed. Buy a digital scale .01
gram resolution. My Acculab is much more easy and
quick to use than the beam balance Ohaus I've
put on the shelf. A small capacity scale
will do very well.                                          Dan

It can, but not necessarily. Many of the chemical are sold in fixed
units such as 1 lb, and the amounts used are different for different
chemicals, so you end up using much less of some, and then they go bad.

For instance, sodium sulphite is used in most developers at the rate of
at least 100 grammes/litre.

Metol is used at 1/50th of that, as is borax and hydroquinone (in D-76)

If you buy large amounts of glycin, metol, or hydroquinone, the cost
savings will disappear because it will go bad before you use it.

If you buy small amounts of glycin, metol or hydroquinone, the cost
savings will disappear because the measuring, packaging and shipping
costs are higher.

I can't mix fixer much cheaper than I can buy it, so I don't.

All my developers are home-mixed, because with the exception of
Phenidone and Metol I can buy everything else at the grocery store or
health food store.  I also use my film developer as a one-shot, and
given my technique of doing a divided paper developer, I estimate that
it probably costs me mere pennies for each batch I use.  It's the
cheapest part of anything to do with my photo habit.