Film base looks blue in scans? (Vuescan + Microtek 120tf + Portra/Ektar/others)

[pbo]

Hi everyone,

Hoping to get some help with my scanning process. I'm using Vuescan with a Microtek 120tf scanner and when scanning negative film somehow all my scans have a blueish film base instead of the expected orange.

I'm attaching my Vuescan settings as well as what my raw file looks like (added +2 exposure to make it less dark, for forum viewing purposes). If anyone wants to check it out, I can upload the full raw file as well. The exposure/film base were locked after the preview > lock exposure > preview > lock film base process.

Any idea what I'm doing wrong here?

Thanks,
Bo

 

[Adrian Gabor]

Nothing is wrong with this, it's just the scanner aligning the RGB channels, but it doesn't really do anything from my findings, unless it is doing analog gain on each channel, in which case it would indeed be better.

 

[Ted Baker]

Hi everyone,

Hoping to get some help with my scanning process. I'm using Vuescan with a Microtek 120tf scanner and when scanning negative film somehow all my scans have a blueish film base instead of the expected orange.

I'm attaching my Vuescan settings as well as what my raw file looks like (added +2 exposure to make it less dark, for forum viewing purposes). If anyone wants to check it out, I can upload the full raw file as well. The exposure/film base were locked after the preview > lock exposure > preview > lock film base process.

Any idea what I'm doing wrong here?

Thanks,
Bo

That's intentional, vuescan will automatically adjust the gain or exposure, of the channels, if the scanner is capable, or it will do it digitally. This will results in a better Dmax and resolution for the blue layer. You gain about 1.5 to 2 stops, you can see how this works if you use the raw scanning graph.

if you want to have the orange mask, just scan as positive, you will get the same raw file, but it will not tell the scanner to adjust the channels.

 

[pbo]

Thank you both, I did not know this was a feature! I tried scan as positive and indeed got the orange mask.