some strange color cast/results.

[Sapphirephoenix2]

Hi, I've been shooting some constructed cameras that for all intensive purpouses are pinhole cameras. I have started using a regular pinhole camera with a 4x5 back and shooting both color positive and color negative film. I've developed them with c41 so they colors shift or they come out normally. The film I use is both old and new.

My question arrived when I turned in some film, and all the film has orange casts to them. The ones with the most cast whch are almost completely orange/red. I have been scanning and editing the colors in photoshop but these past ones are beyond changing.

Is my problem just the film or is it something else I am doing? The film with the most issue is with porta 100T film. I dont think its really an issue, the images came out very interesting. More a curiosity of the color shifts.

[edp]

Did you put the film in with the emulsion facing the pinhole? If you expose it through the base it will come out with a very strong red or orange cast.

[Perry Way]

perhaps this link might provide some clues. along with reciprocity calculations there is also filter corrections necessary for low light exposures.

http://photo.net/learn/nature/reciprocity

[Ed Sukach]

..shooting both color positive and color negative film. I've developed them with c41 so they colors shift or they come out normally.

Are you using C41 chemistry for BOTH color negative AND color trransparency film? If so, the color transparency should require E-6 chemistry. Check the film package.

Processing C41 in E6 chemistry, or vice versa, *will* give unusual results - this is known as cross processing.


Is my problem just the film or is it something else I am doing? The film with the most issue is with porta 100T film. I dont think its really an issue, the images came out very interesting. More a curiosity of the color shifts.

The "T" at the end would indicate that the film color is "balanced" for artifcial (Tungsten) lighting. Using it in "daylight" should give you a heavy cyan (bluish) cast - but using the wrong chemistry (cross processing) ... I really don't have any idea of what it would look like.

[Perry Way]

The color shifts with reciprocity. The further you get to reciprocity failure the further the shift of color.

[tiberiustibz]

Yes tungsten film will give an orange cast to all your images unless they're shot indoors under tungsten light. BTW I know people who will pay for that Portra 100T or trade daylight film for it.