LaserSoft Imaging

Hello,

As I Scan a lot of different type of Slides Films, and because ICC profiling for each film, and change ICC profile before each stack of slides takes lot of money (for IT8 targets) and time I was just wondering :

Why a similar plug-in like negafix doesn't exist for slide films ? Do you plan to implement it in the future ? I think it would be a very helpful and time-saving plug-in !

How could work the system :
- you furbish with silverfast a "generic" IT8 slide target
- we profile our scanner with this target trough silverfast auto IT8 profiling system
- then before scan a stack of slides, you choose in the list the type of slide you want to scan (a bit like choosing between kodachrome, positive, or negative in the general options of silverfast)
- at the moment of the preview the slide should look quite like the original and we have now a good basis for working
- then we can make the other settings that we want (white balance ...) and we have a quality controlled (and repeatable) digitized file of the original, with the possibility to improve the "original"

I precise that I work with Nikon 5000ED (+SF210 feeder) and Epson V750 scanners on Mac with Silverfast Ai 6.6.

Thanks.

Dear customer,

It is not necessary to calibrate for each different slide film (with the exception of Kodachrome).

The It8 calibration measures the available color-space for the scanning device.
This is not film specific.

The only exception is Kodachrome.
For this slide film we offer a special Kodachrome mode which automatically selects the correct profile when switching between transparency and Kodachrome mode.


kind regards,
Arne Ketelhohn.

Hello,

You say the only exception is Kodachrome ... could you explain me why please ? What's the reasoning that make you think that kodachrome is much different than other kind of slides ?
I scan everyday lot of slides and every brand/film is different each from other ... exactly like negatives. And there is negafix.

So when you say it is not necessary to calibrate for each different slide film, It's your point of view, and if I want that each kind of slide can be scanned with the same rendering, I can't do it with silverfast.

My point of view is that you just want really answer my question ...

Regards

Dear customer,

Kodachrome slides have a significant blue colorcast.
To remove this we offer the special Kodachrome mode.
This requires a special ICC profile.
To create individual ICC Profiles for this specialized colorcast removal process a Kodachrome target has to be used for the calibration.
Other films do not require such a profile.
Normal slide film is scanned using the scanner specific ICC profile which reflects the characteristic of the scanner.
This is not our "opinion" but the way an IT8 calibration functions.
The IT8 calibration is a device calibration and has nothing to do with the scanned film material.
It measures the colorspace available to the individual device.
This is not a film specific process.


kind regards,
Arne Ketelhohn.

Dear Benpearl,

Kodachrome used a completely different dye set from the other slide film types all of which were very similar E6 type dye sets. The dyes affect how the CCD or CMOS sensor sees the light source in the scanner. Once that "seeing" has been profiled, it can be used across any of the E6 type dye set transparencies. Kodachrome was the exception. IIRC, Fuji Velvia was another that could benefit from specific profile, but it wasn't really required. It was only useful if you were using the pro version of the film.

If you want to set up a set if IT-8 profiles for each slide film type, go ahead. That will be a first for the industry.

The reason for the individual negafix profiles is that each type of negative film has a different curve required to invert the image into a positive and have reasonable colors. With slides, we start with a positive and just need to know the spectral profile of the film for the light source and sensor. You really don't need negafix if you don't want to use it. Just bring the image into Photoshop, invert, and adjust using curves until it matches what you want the image to be. Negafix just automates the process some.

It sounds from your original question that you need to shoot a color checker target for each set of shots and light conditions so you can get the color balance and B/W points set after IT-8 correction. That is above and beyond what the IT-8 profiling process is used for.