HOW TO FIND OUT PROCESSING TIMES FOR ANY FILM IN ANY DEVELOPER - is this true?

[TheToadMen]

I read a discussion on finding developing times for WEPHOTA NP 22 (4x5"), where some gave this simple method to determine developing times:

I'll brake a pledge of OMETRA and tell you a secret given by American war photographers to Russian war photographers at the end of World War II.HOW TO FIND OUT PROCESSING TIME OF ANY FILM IN ANY DEVELOPER:
1. In a darkroom cut off a few strips 6-8 mm wide from the film you want to develop.
2. Turn the lights on. The strips are fogged now.
3. Take one strip with your right hand and a stopwatch with your left hand.
4. Dip one half of the strip in a developer and start a stop watch. The emulsion side of thefilm strip placed in a developer will start lightening first and then darkening.
5. WHEN THE DARKNESS OF BOTH PARTS OF THE STRIP MATCH STOP THE STOPWATCH!
6. Divide the number of SECONDS shown by the stopwatch by 3. This is your developingtime in MINUTES. If stopwatch shows 24 seconds, developing time is 8 minutes.
7. Repeat two-three times for consistency.
This method never failed for the last 60 years.

(source: http://photo.net/black-and-white-photo-film-processing-forum/00b4nz)

I was wondering: could it really be that simple? Not exact science - I know - but if it works a good method to find a starting point for any unknown film.
Has anyone actually tried this?

 

[pdeeh]

I would have thought it easier to look at the manufacturer's data and start from there ...

 

[John Wiegerink]

I think it might get you an excellent starting point, but I wonder about staining developers and this method. I might compare Pyrocat-HD just to see. Not so much about the stain, but these developers rely on the stain to alter the final brightness range. Just curious and I'm going to try this with some D76 to see if it gets me close to what I already have for a time. If this works I'm writing it on my bathroom stall so I can read it several times a day. JohnW

 

[jp498]

Manufacturer's data doesn't work when you're using a third party or non-mass-market developer.

I haven't had a need to try this. I have a binder in the darkroom with printouts from the massive dev chart for each developer I use. It gets me close.

 

[John Wiegerink]

Manufacturer's data doesn't work when you're using a third party or non-mass-market developer.

I haven't had a need to try this. I have a binder in the darkroom with printouts from the massive dev chart for each developer I use. It gets me close.

I agree that the MDC is a Godsend sometimes, but it ain't perfect either. At least not for me and Arista EDU/Foma 100 120 film. This method might have saved me a little time and material if it works. JohnW

 

[TheToadMen]

The original question came up when someone was looking for developing times for WEPHOTA B&W films. The manufacturer didn't provide info and it wasn't on the massive dev charts. Hence the original question about this tip ;-)

Good point about staining developers, though. I guess this will be different compared to "normal" developers like D76 or Rodinal.

 

[pentaxuser]

I'll have to try this and see how close it gets me to the times I use for Xtol and my range of films.

I have used the leader to test for potentially exhausted developer but never tried this test. Just on a point of clarification. My fogged leader before development is usually a greyish colour and when fully immersed goes black after a few minutes. I had never noticed it go through a grey stage and yet as the test involves keeping half out of the developer and matching then it presumably must?


I'll need to watch more closely in future

pentaxuser