Cyan cast. Sign of what?

[Bormental]

@Rudeofus this make sense. The cyan cast is on the positive, this means that the cyan layer on the film got under-developed, and since it's the one at the bottom, it makes sense for me to accept Adrian's suggestion. This is also compatible with another observation: only my medium format rolls have this problem, and they got developed in a larger tank which I couldn't submerge into the hot batch as fully as the smaller tank I used for 35mm.

 

[RoboRepublic]

Just curious if the cast is on Pro 400h?

 

[Вormental_old]

@RoboRepublic It was Portra 160 and 800. This was indeed the case of underdevelopment, as I was using a gigantic Paternson tank (holds 5 reels) with just 2 reels loaded, the temperature dropped way too much, I switched to smaller tanks that I fully fill & pre-soak with 102F water and never saw this again.

 

[bernard_L]

Maybe I'm thick, but I don't get the notion of a cast blamed on a color negative. Relative to what? With all the variations between the color of the orange mask seen between different emulsions?
As much as circumstances allow, on each color film, I take one dedicated frame of a neutral gray card, sunny weather, open space, sun incident at approx 45° on the card; ideally a few cumulus hanging around. This can then be used to establish global color balance, whether wet process or the process That Shall Not Be Named.
Disclaimers:

• Crossover, which may be a problem with non-nominal dev. But you mention cast, not crossover.
  
• Blue cast in open shadows, versus sunlit parts of the scene. That is an intrinsic property of the scene.

 

[Вormental_old]

@bernard_L did you read the first post?

 

[bernard_L]

My bad, I missed "especially in the highlights". Indeed consistent with under-development of the cyan layer.Note however that through the thread, "cast" is mentioned, and never "crossover".
Then for on-film calibration, upgrade from gray card to gray step tablet. And achieve proper neutrality in post for both low and high values.

 

[pentaxuser]

@Rudeofus this make sense. The cyan cast is on the positive, this means that the cyan layer on the film got under-developed, and since it's the one at the bottom, it makes sense for me to accept Adrian's suggestion. This is also compatible with another observation: only my medium format rolls have this problem, and they got developed in a larger tank which I couldn't submerge into the hot batch as fully as the smaller tank I used for 35mm.

Any idea of the temperature difference compared to that of the 35mm film? It would be nice to know how much leeway exists in the safe temp range
Thanks

pentaxuser

 

[BainDarret]

The cyan cast could be a result of leuco-cyan dye formation that can occur when bleaching is incomplete. Perhaps try re bleaching the film in fresh bleach (or blix) to see if that corrects the problem.

 

[Вormental_old]

@BainDarret good tip, thanks!