If you were formulating an new film developer...

What "markers" would tell you that your brainchild succeeded?

1. Lack of base fog AND adequate density?
2. Contrast range that gives good tonality on contrast grade 2 paper?
3. your next marker...

In brief, what tells you that your new film developer formula is a success?

My approach would be:

1. Find out what detective quantum efficiency (DQE) is
2. Find out how to do tests to measure DQE
3. Create a developer which improves DQE over Xtol
4. Find a balance between speed, grain and sharpness that suits your need

Don't forget cost. Some dev agents are pricey. Do you want to spend more or less?

I've seen it discussed here that Kodak would ask how different from any other developer they made. If it was not that different, they moved on.

There is so much out there already, unless someone comes up with a new developer compound, what we have already is it.

Me, i play with single purpose stuff. Like adding glycine to d72 to build up better mid tones. In my opinion, the big stuff has been done.

Sent from my Nexus 5 using Tapatalk

Another approach, make a developer out of easily obtainable ingredients: tylenol (reacted with lye to make para-aminophenol) from the drug store, ascorbic acid from the health food store, sodium ascorbate from the health food store, washing soda (sodium carbonate) from the grocery store, borax from the grocery store, maybe sodium bicarbonate from the grocery store, instant coffee from the grocery store, sodium sulfite from the swimming pool store, etc.

The idea here is photographic survival when the end of the world comes, or when vendors of photographic chemicals leave the business, whichever comes first.

I’ve always dreamt of making a developer from pee. Somebody overtook me: http://kwerfeldein.de/2012/07/04/der-vollblut-fotograf-entwickeln-mit-peeneol/.

A developer that ships as a pre-mixed powder, but mixes up into a one litre, highly concentrated stock solution in either water or glycol. The water based stock should have a shelf life of at least 6 months in a half filled bottle. The glycol based stock should have a much longer shelf life. Either stock should be easy to mix, at or near room temperature. The powder itself must be easy and safe to handle.

The mixed stock should be usable in working strength dilutions that range between 1+9 through 1+29, with the potential of using more dilute versions for stand or semi-stand developing.

The developer should be usable in a replenishment regime, where the developer serves as its own replenisher.

The developer should be environmentally relatively benign, without being particularly susceptible to water quality variations.

A package of developer (sufficient to make 1 litre of stock) should sell for no more than $10.00 CDN. The package itself should be well sealed, strong and easy for retailers to either display or ship (without any hazardous goods concerns).

Simple right?

Please report back when you have made progress

SchwinnParamount said:

What "markers" would tell you that your brainchild succeeded?

1. Lack of base fog AND adequate density?
2. Contrast range that gives good tonality on contrast grade 2 paper?
3. your next marker...

In brief, what tells you that your new film developer formula is a success?

Click to expand...

ease of use, and flexibility of use.
to me basefog &c play second fiddle to how easy it is to mix and use ...

( that's why i "invented" Dcaffenol, and sumatranol130 before that ... not really invent but mixed together
it must have been like mamie taylor asking for what is now known as a mamie taylor ...
the barkeep must have been out of rum when she asked for a dark and stormy, so she might have said: just throw the cheapest
scotch you have in there, instead ... )

alanrockwood said:

Another approach, make a developer out of easily obtainable ingredients: tylenol (reacted with lye to make para-aminophenol) from the drug store, ascorbic acid from the health food store, sodium ascorbate from the health food store, washing soda (sodium carbonate) from the grocery store, borax from the grocery store, maybe sodium bicarbonate from the grocery store, instant coffee from the grocery store, sodium sulfite from the swimming pool store, etc.

The idea here is photographic survival when the end of the world comes, or when vendors of photographic chemicals leave the business, whichever comes first.

Click to expand...

Been there, done that, start on post 28:
(there was a url link here which no longer exists)
There are substances with solvent properties that could be added to PC-TEA which have not been investigated, including their potential hazards.