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View Full Version : Initial Test of Scanning separate channels with Vuescan and Combining



Steven Ruttenberg
28-Nov-2018, 21:25
Here is the link to all the files. https://flic.kr/s/aHskJPAu9k

I scanned the red, green and blue channels with exposure locked, 16bit gray transparency with multisample to 16. Saved as raw linear tifs. Brought into PS, did not assign a color space yet. Combined them, assigned Adobergb then converted with ColorPerfect. I then attempted to adjust the white balance as best I could.

The rgb file was scanned with 48bit input and output with Vuescan and saved as raw linear tif. I converted with Colorperfect.

The image was made on Portra 160, 75mm Nikkor at f/22 and 1/15 of a second.

Both images are extremely close, I think the one where I combined the three files has a slight colorcast on the dirt that I don't seem to be able to get rid of. That could be from when I converted it in Colorperfect. I manually adjusted. For the rgb file, I chose the optimized version so there are some differences. The basic premise of combining three separate channels made with Vuescan or any other scanner, has some merit, if you output file is going to exceed the 4gb tif limit. If not, then not really needed. Just choose image, scan highest dpi that is still under 4gb limit (if you want) then save as raw linear tif. Be sure to choose 48bit rgb in and out and lock exposure. This will allow you to adjust scan brightness that should be recorded when file is saved as the linear tif file. According to Ed, the 48bit rgb option is sharper than 16 bit grey because the three channels are averaged together. He didn't say how though.

I am doing this for color slides, color negatives, and black and white negatives. And If I ever run across a b/w slide film for 4x5, I would use the same settings as well.

RGB SCAN
https://farm5.staticflickr.com/4882/45185600175_ea87e26e77_b.jpg (https://flic.kr/p/2bQU1FZ)20180610_rgb_Converted_0063 (https://flic.kr/p/2bQU1FZ) by Steven Ruttenberg (https://www.flickr.com/photos/157376714@N08/), on Flickr


Combined Red, Green, and Blue
https://farm5.staticflickr.com/4849/31158227637_bcd4fa83ca_b.jpg (https://flic.kr/p/Ptm4xk)20180610_red_green_blue_20181127_0063 (https://flic.kr/p/Ptm4xk) by Steven Ruttenberg (https://www.flickr.com/photos/157376714@N08/), on Flickr

Steven Ruttenberg
28-Nov-2018, 21:26
Feel free to down files and play around. Tifs are the full size linear raw files.