Diafine at box speed?

[BetterSense]

I just made a couple exposures of a squirrel on 6x6 Neopan 400 that I kind of want. Trouble is, I metered the scene afterwords with my OM2 and it seems that I underexposed by 2-3 stops. Normally what I do for a 2-stop push is use Diafine. Trouble is there were a bunch of exposures on the roll before that were exposed in daylight at box speed or a little under if anything. They are probably just as valuable as the squirrel exposures. I've never tried Diafine on exposures made at box speed so I'm not sure whether to try to push with D76 or use Diafine. If it wasn't for the recent underexposure I would probably develop for ten percent less than the standard time like I always do when I shoot in Texas sunlight.

 

[panchro-press]

Hence, the reason for tossing a coin.

-30-

 

[takef586]

Just process normally in Diafine. I have developed various rolls of Tri-X with the exposure varying between EI 100-1600 on the same roll, and all shots were printable, although i would not normally want to shoot below EI 400 because of loss of sharpness and low contrast.

 

[Tim Gray]

Sounds like a job for Diafine to me. The shots with more exposure should come out with less contrast, all things being equal. If you go with D76, some of the shots will either be over developed or under developed, end of story. Diafine won't do this. Sometimes when I get a random 100 speed film and I don't have any developer info for XTOL, I just shoot it at box speed and develop in Diafine. The negs always come out reasonably ok.

 

[BetterSense]

Ok; my priority was to not ruin the normally-exposed frames.

If I was to develop normally in D76, would a -2 stops exposed frame be salvagable? I'm pretty sure I exposed a shot of the Alamo +4 stops and I at least managed to get an image out of it.

 

[philipp.leser]

At least in my process, Neopan 400 has an actual speed of EI 320 in Diafine. It does get a bit dense that way, but I get 0.1 log D for zone 1, which is what I care about.

 

[Tim Gray]

-2 stops seems to be asking a lot if you aren't going to push develop. Especially if you are planning on printing this traditionally and not scan. You might want to try a test roll and develop in Diafine and see what happens.

 

[Andrew Moxom]

Neopan is one of the films that requires a lot more shadow detail exposure. I find this film more like ISO 200 in all actuality with most developers. Even though Diafine does give above box speed with most films, I would still err on overexpsoure of Neopan 400 film.

 

[BetterSense]

I developed the film in Diafine. As I said before my best guess was that the shot was -2 stops according to the OM2 I metered the scene with afterwords. The negative looks a bit thin but usable. Unfortunately I ran out of paper before I got to the underexposed shots, but they look printable. The rest of the frames look denser than they usually are with D76 but I have already printed a couple of them with no trouble and good results except that the grain is much more visible than it is with D76. This is the first time I've used Diafine with 6x6 negatives and seeing visible grain in an 8x8 print was a bit of a change.

As far as the effective speed of Neopan 400, I only use it in medium format and only in meterless cameras. I use Sunny 16 as if the film was a 400 speed film and I get reasonably good negatives this way. With a 60 year old camera the shutter speed could well be slower than indicated and I might be exposing it as a 200 speed film, but I can't really say.

This was a guess exposure, but it was the same 'eyeball' density as my sunny-16 shots.

Diafine "at the same speed I'm using when I use sunny 16 as if it was a 400 speed film":