Same film, same developer, very different results?

[Evan_Mathis]

I just prepped a brand new batch of PyrocatHD and made a coupld of step tests to work with an app that I've been jamming on, and something weird is happening.
Both films here are Fuji Neopan Acros II, the one on the bottom is 35mm the one on the top is 120.
Both processed at the same time, 18 min @ 20°C in PyrocatHD (this has been my working time for Acros II so far with no issues)
Obviously very different results. The only difference is that i bought the 120 film a few months ago from B&H, the 35mm last week from Samy's in LA. All kept in the fridge.
The EI for the 35mm is 91 and an EI of 27 for the 120. It also looks like the burn in data on the edge of the film is much lighter on the 120.
Do you think this is a case of me being sold expired 120? There is the possibility that the 50mm Mamiya Sekor C lens might have a mal-adjusted shutter, but that wouldn't account for the burn in being so light and the different shades of the film base...
Thoughts?

 

[mshchem]

Fuji lists both 120 and 135, 7 1/4 minutes in D-76 @ 20°C. So theoretically both films should behave the same. I would be surprised if either store is sitting on old film. I am a XTOL or HC-110 type. I would look at your chemistry first. MHOFWIW

Oh yeah, Welcome! Look for some others here to offer another explanation.

 

[koraks]

that wouldn't account for the burn in being so light and the different shades of the film base...

120 and 135 are coated on a different base, so that they're of a different color isn't surprising. The blue color of the 135 is part of the anti-halation package of this film; on 120 this is handled differently, I assume on this film also with a dye that's included in either the backside anti-curl coat (which 135 lacks altogether) or underneath the image layer.

Edge print is generally not of controlled density so you can't say much on that basis.

For the difference in densitometry I'd primarily look for methodological problems on your side.

 

[loccdor]

I have recently shot expired, non-frozen Acros from multiple batches, 35mm and 120, expired 10-20 years ago. None of it had speed that dropped very much at all, exposing it at 50 always resulted in what looked like slight overexposure. I know it's not precisely the same film, but I'd be surprised if your fresh Acros II had dropped to such a low speed.

 

[Don_ih]

The edge printing on both looks the same, not that that really matters. The content of the photos on each, however, look different. See how you metered. If there was any significant extension of the lens in the 120 photos, that could cause a bit of underexposure. What is your app testing? A spot or the overall image? The overall image in the 120 appears to be of something dark, which should end up thin on your negative. The majority of the 135 film is of the lighter background, which ends up more dense on the negative. The average density of those 120 photos would be much lower than that of the 135, because of what's in the photos.

 

[pentaxuser]

The EI for the 35mm is 91 and an EI of 27 for the 120.

View attachment 416235View attachment 416236

Doesn't the two vastly different EI exposures make quite a difference to the look of the negs if everything else such as dev time etc remains the same ?

As no-one else has picked up on this maybe I am wrong in saying it has any effect but if it doesn't then I wonder why?

pentaxuser

 

[loccdor]

Doesn't the two vastly different EI exposures make quite a difference to the look of the negs if everything else such as dev time etc remains the same ?

As no-one else has picked up on this maybe I am wrong in saying it has any effect but if it doesn't then I wonder why?

pentaxuser

I think he's talking about the EI based on his interpretation of the results, not the speed the film was shot at. It would be pretty hard to purposely shoot film at an odd EI like 91 or 27 anyway.

 

[Saganich]

There's no indicating what the differences might be....same film, same developer, different everything else. you may want to set up a controlled experiment if your curious.