Vuescan again, "GENERIC" vs "Tmax" profiles

[Takkun]

As always, a problem figuring out VueScan that's probably been asked, but I figured I'd ask after spending a couple hours looking at decades old photo.net posts...

Scanner is Nikon LS-4000. Film is TMY2 that looks a little thin to my eyes, but does have detail in the shadows. (shot 6 years ago, possibly at box speed)

Normally I use the lock exposure technique (though sometimes that gives me values near 30), set color to NONE, curve at .25/.75 (straight curve), and 'GENERIC COLOR' for the film profile. I turn on the 'pixel colors' tickbox to see what is in gamut.

The last roll I just scanned, almost everything in shadow was being clipped with the histogram far to the left. Switched to the default TMax D76 CI-.40, and everything was showing up, albeit with a fairly narrow histogram.

Perhaps its worth mentioning that this difference was looking at a preview scan—in the app without any change in exposure.

What gives here? From what I've seen from the numerous tutorials and the like, the standard advice is leave it on 'none' and generic, with a few suggesting auto levels.

 

[Takkun]

Example of what I'm seeing:

versus:

 

[Bob Michaels]

Takkun: you are worrying about all those profiles and adjustments that are there solely for the use of those who only want an acceptable looking file straight out of Vuescan and do not later use an image editor such as Lightroom or Photoshop. You can ignore them.

Simply strive to digitize the maximum amount of data from the film, not what the file from Vuescan looks like. That means ignoring all of those adjustments other than making sure the ends of the histogram are not clipped. Then use your image editor to create the photo that looks the way you want it to.

FWIW, I am coming up on my 20th year of using Vuescan. It was after year one that I realized none of those profiles or adjustments were necessary as I was doing all of that to a much higher degree of precision, could see the effect of what I did on the scree, and reverse if necessary in Photoshop.

 

[Takkun]

Bob,
That's always my intention, of course—to minimize VueScan's processing in favor of my own later on. I was curious what the film profiles other than generic did specifically, since for some of my thinnest negs it looked like it evened out the histogram on darker shots, rather than being bunched to the left. Hence using them for some tricky images, trying to get a more usable file.

After looking at those scans in PS/Aperture, it seems that it shifts the tones left (which, at first glance sounds like a good idea) but is really shifting the blacks further toward middle gray, and adding a lot of noise in the process. You can see that in the preview images above. Using the generic profile, VueScan tells me it's clipping the shadows (blue), but I can still pull them up in post, without the noise.

Looks like I'll be re-scanning a few rolls this afternoon...