Topic: Kodachrome scans too dark using Silverfast (Read 9830 times)

PSA DC-9-30 · « **on:** March 10, 2008, 11:23:45 pm »

I've been trying to get the feel for scanning my Kodachromes with a new Epson V700. I've been scanning at 6400 ppi, 16 bit, Adobe RGB (yes the file sizes are monstrous) using the Silverfast SE software that came with the scanner. Anyway, using the Scan Pilot, I am optimizing levels and previewing the scan before pulling the trigger. In the preview everything looks fine, but the scan itself comes up way too dark (probably by 3 or 4 stops), with a marked cyan cast.

Just to check if the scanner's analog gain / lamp is bright enough, I tried the scans using the Epson interface. The result is vastly better, but unfortunately is in sRGB.

Anyone know what I'm doing wrong? Thanks.

muv · « **Reply #1 on:** March 11, 2008, 10:54:48 am »

It sounds to me like your scanning in the HDR mode. That scan would would need to be processed with Silverfast HDR. This is the technique I use and it is well worth it. Scanning Kodachrome is problematic at best with Silverfast. All scans are very cyan, but are easier and better to correct with the HDR software than in Photoshop. Unfortunately Silverfast uses their own proprietary film targets that work with the built-in calibration, but the Kodak Q60 Kodachrome does not work with this function. Silverfast offers only an Ectachrome target, which does an excellent job calibrating a scanner. Maybe someone else has figured out how to use a Q60. Good luck.

PSA DC-9-30 · « **Reply #2 on:** March 12, 2008, 05:44:11 am »

Thanks.

I was indeed scanning in HDR mode, but I still find it odd that one cannot correct for these problems before the scan, especially when all looks OK in the preview. Other than HDR, the only other option I see that remotely looks like 16 bit is labeled: "48 -> 24 bit" , and what this means is far from clear to me.

Nat Coalson · « **Reply #3 on:** March 12, 2008, 08:15:29 pm »

If you're scanning to 16-bit I recommend using the 48-bit HDR option (this means 16 bits per channel : 3x16=48) and not doing any kind of color adjustments whatsoever in Silverfast. You want to get the maximum amount of data from the scanner without software modification.

To deal with the darkness issue, look under the Advanced options on the General tab... adjust the Gamma to 2.2 as a starting point; the default is 1.8.

Also look for the CMS settings and make sure everything is optimal.

Depending on the scanner and the film stock, you may not get perfect color. But you're better off doing your color adjustments to a 16-bit file in Photoshop than trying to tweak the Silverfast settings.

muv · « **Reply #4 on:** March 13, 2008, 09:55:53 am »

Quote

If you're scanning to 16-bit I recommend using the 48-bit HDR option (this means 16 bits per channel : 3x16=48) and not doing any kind of color adjustments whatsoever in Silverfast. You want to get the maximum amount of data from the scanner without software modification.

To deal with the darkness issue, look under the Advanced options on the General tab... adjust the Gamma to 2.2 as a starting point; the default is 1.8.

Also look for the CMS settings and make sure everything is optimal.

Depending on the scanner and the film stock, you may not get perfect color. But you're better off doing your color adjustments to a 16-bit file in Photoshop than trying to tweak the Silverfast settings.
[{POST_SNAPBACK}][/a]

If you scan in HDR mode you will get a file that has to be processed with Silverfast HDR, which is a separate piece of software (app.$300.) from the scanning software. When in this mode all color and tone correction functions are disabled. Your scanned image will look very dark until opened in Silverfast HDR. Go to [a href=\"http://www.computer-darkroom.com/sf5_contents.htm]http://www.computer-darkroom.com/sf5_contents.htm[/url] for tutorials on how to set up Silverfast AI and Silverfast HDR to get the best quality scans. The preferences in each piece of software are tricky and different for a calibrated or uncalibrated scanner. In my experience scanning in HDR mode and processing with Silverfast HDR takes my scans to another level in preserving information, detail, and the atmospheric qualities of my images. You should do all of your color and tone correction in Silverfast HDR before opening in Photoshop. You will end up with a "raw" HDR scan, the processed image, then save as in Photoshop to start a master file for that image. Good luck PSA.

Nat Coalson · « **Reply #5 on:** March 13, 2008, 11:55:59 am »

Thanks for the info muv. Sounds like the separate Silverfast HDR app is worth buying.

PSA DC-9-30 · « **Reply #6 on:** March 14, 2008, 05:09:30 am »

Thanks gentlemen,

I am continuing to scan in HDR, but am tweaking in PS CS2 for now. I am scanning with the color space set to Adobe RGB, but for some reason, in PS, under Edit/Color Information, it says "sRGB".

F. Meyers · « **Reply #7 on:** March 27, 2009, 07:59:38 am »

Quote from: muv

... Silverfast offers only an Ectachrome target ...

In the meantime SilverFast came up with a Kodachrome target.
Check the newsletter: http://www.silverfast.com/show/newsletter2...html#kodachrome

SilverFast has a complete kodachrome workflow now. So you don't need to extemporise with HDR scanning anymore.
They say you can even use dust and scratch removal on kodachromes now.

Author Topic: Kodachrome scans too dark using Silverfast (Read 9830 times)