Reciprocity Correction and Development Expansion

[John Irvine]

I got into a situation where the calculated exposure in subdued light put me into the range of reciprocity failure, 6 sec with TX 320 at ASA 200. Kodak says give it 25 sec exposure. No problem. I made two exposures and developed one at N+1 and one at N+2. Negatives look good and seem to have taken care of the problems I had in "Exposure in the woods" discussed here a couple of days ago. (Thanks everybody for the guidance).

Today I noticed that Kodak also says in addition to increasing the exposure, decrease the development about 15%. Since I am increasing the development to expand the tonal range, should I have left it at N+1 and N+2, or taken those numbers and decreased them 15%? Or would the negatives have not shown the difference.

 

[CBG]

If the negs look good - and presuming they print well - you probably nailed it - and I would guess the original scene deserved a bit of extra development to obtain a normal contrast range. If they are too contrasty, then maybe you did add a bit more development than desirable.

Ordinarily, reciprocity failure and extra exposure to correct do bump up the contrast and would suggest a slight reduction in development.

C

 

[Claire Senft]

I agree with CBG, alway be ready to accept success. If you feel that the prints require a paper of lower than usual contrast then make a test next time.

 

[John Irvine]

I printed them both last night. N+2 took about 15% more exposure to get the same tone at the low end. There is not much difference between the prints. There may be a little loss of detail in a couple of the lightest spots in N+2. Looks like N+1 got the prize.