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IanBarber
30-Mar-2017, 06:10
My normal processing consists of using a Paterson tank and a Mod54 to hold the 4x5 sheets of FomaPan 100 film.

I use Xtol stock which I replenish with 75ml after every 4 sheets of developed film.

For FomaPan 100 exposed at 50 ISO, I develop for 6 minutes, agitating continuously for the first 60 seconds, then 3 agitations every minute.

Since trying some Pinhole work on a 4x5 Noon pinhole camera, I am noticing that the negatives appear much flatter in contrast than when I develop the same type of film exposed with the 5x4 Chamonix camera.

Is the lower contrast just an inherent part of pinhole photography due to it not using a regular lens or should I be using a different approach during the development stage.

Ian

koraks
30-Mar-2017, 06:51
You can count on the lack of contrast being inherent to the way you expose. Not necessarily to the use of a pinhole; you may have a light leak somewhere in your setup. But there's nothing in pinhole photography that necessitates a fundamentally different approach towards development.

What you do need to take into account is the reciprocity failure of this particular film. It's quite significant accounted particularly relevant for the longer exposures that you'll run into with pinhole.

Jim Jones
30-Mar-2017, 11:38
In addition to Koraks' comment, pinhole images tend to lack contrast due to the scattering of light around the edges of the pinhole. Increased development should help compensate both for this and for the reciprocity failure of the film.

IanBarber
30-Mar-2017, 11:53
In addition to Koraks' comment, pinhole images tend to lack contrast due to the scattering of light around the edges of the pinhole. Increased development should help compensate both for this and for the reciprocity failure of the film.

Doesn't reciprocity already increase contrast and wouldn't increasing the development time increase this further ?

koraks
30-Mar-2017, 12:05
Yes, but the odds that they exactly cancel each other out are very slim.

Doremus Scudder
31-Mar-2017, 08:17
Are you sure your reduced contrast isn't underexposure? Calculating exposure for pinholes is a bit trickier due to the very small aperture. If you're using long exposures and not compensating for reciprocity failure, you're underexposing. Check shadow detail on your negs.

The bit of diffraction and overall flare you get from a pinhole aside, the same exposure and the same development should yield negatives of similar contrast (dependent on the SBR in the original scene, of course).

My occasional pinhole negatives look just like my negs taken with lenses in terms of density and contrast. So should yours.

Best,

Doremus

IanBarber
31-Mar-2017, 09:37
Are you sure your reduced contrast isn't underexposure?

Good point Doremus, next time I do an exposure, I will take better notes and evaluate the negatives on the light box