I’m about to begin a project of digitizing my Dad’s slides from 1971-1983, and then negatives from late '70s - 2005 (when he went digital).
There’s plenty of tips and info about best practices for scanning negatives, so I’m all set there. But I don’t see much about how to optimize slide positive scans. Got any tips about white balance, exposure compensation, etc?
For example, for negatives you expose to the right to gather more detail, but in my tests with slides I’ve kept exp.comp. at 0. It seems fine. Please offer me some, “Well, actuallys”.
I’m using Sony A7IV, Sigma 70mm macro, Negative Supply Light Source 35 LED Panel for Film Scanner (97 CRI), and finally arriving on Tuesday: Essential Film Holder.
My negative scanning settings are: WB auto sunlight, ISO 100, F/8, exp. comp. +1.3 (though I’m not afraid to adjust when it seems necessary). To shoot in the daytime I also made a little light blocking tube that fits snuggly on the lens hood using Rosebrand wool serge 30oz.
EDIT: Regarding exposure compensation and metering mode,
I haven’t nailed down what’s the best interplay. With slides, it’s maybe best at +0 and “full frame”?
As I suggested above, for negatives I’ve created a preset with +1.3. Also use “full frame” metering, or maybe “highlights”?
You found a lot of hints on how to cope with negatives, but good practices for slides are sparse…yet. NLP has acquired features that relate to slides only recently, therefore the knowledge has to be built first and some of it will find its way into the user guide eventually.
According to what I found testing NLP 3.1 with slides, I can just say that necessary measures depend on the slides, their age, degradation, colour shifts, original exposure and whatnot. This means that we’ll have to find our own ways before we can share a “how-to”. And that is your chance to contribute and share your learnings.
I do propose to test and learn systematically
Scan slides with bracketed exposure
Test HDR rendering of bracketed captures of slides
Don’t try to tune single images, but work on batches
Use virtual copies to save drive space and reduce access delays
Think “starting point” instead of “it doesn’t match my expectation”
Also, I propose that you play with the following
Colour Model (Basic, Frontier, Noritsu etc.)
Pre-Saturation (and I mostly use low values to start with)
Border Buffer (as a variation of or added to crop settings)
Roll Analysis (if the slides have been camera scanned with nearly identical exposure)
Why not just use manual exposure, surely you’d get a better idea of what’s going on? Automatic exposure would adjust according to the content of the slide, which isn’t really what you want given that the density of the film base is a constant. Then bracket as well as necessary.