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View Full Version : Prints Scan good but Negatives scans BLUE



abc123kazu
26-Feb-2013, 16:34
Hi Im using a Linotype-Hell Topaz Scanner with Linocolor 4 software.
I wanted to compare my prints and 4x5 negatives so i tried scanning both.

The print scan fine and beautifully.
However the negative scans with a very blue hue.

I have read somewhere that it is because of emulsion order with film negatives reading blue, green, red (in that order).
Therefore the blue receives the most light and red the least, resulting in the lack of yellows and reds.
I tried pulling down blues with curves but it is getting no where close to the print scan and im losing the gradations.

Im sure this is something that may be apparent in other scanners as well. How do i resolve this issue? Is it something that can be adjusted during scan?

Thank You

Jim Andrada
27-Feb-2013, 23:38
I doubt it's purely the negatives as mine scan fine on an Epson scanner. Haven't tried a higher end scanner, but if it were the emulsion order issue, then everybody's negatives would scan blue regardless of the scanner that was used.

Of course different films have different color casts, but I've never had a negative scan so blue as to be unduly difficult to balance in post processing. Sounds more like a problem with some parameter in the scanning software or in the scanner itself, or some set up or user issue.

Just my humble opinion.

tigger_six
28-Feb-2013, 01:21
You need a correction profile for the given film. Alternatively, shoot a greycard and fix white balance so that it is grey.

Larry Gebhardt
28-Feb-2013, 06:02
I assume this is for color negatives. If black and white, just pick the cleanest channel or two and combine them while desaturating.

For color it sounds like your curves are not lined up. Most likely it's the endpoints are not all coincident. Adjust the endpoints of each channel so the film base just starts to clip in the shadows, and ideally so I highlight just starts to clip. Back off on the highlight so no clipping occurs. The highlights are subjective and you need to balance all so the color at the upper end is neutral. This can all be done in curves or levels in a Photoshop layer. I personally prefer layers to get the color balance right. Once that is done you should have a fairly neutral image. If theres a slight color cast in the midtones you can adjust this with the midtone slide on each channel.

If that's not clear you can upload a low res scan, including the borders and no clipping, and I'll upload a photoshop file back with a simple adjustment. Hopefully it will match your print.

abc123kazu
28-Feb-2013, 11:21
Thank You everybody for the response. Here is the jpegs of both the scan of prints vs the color negative scan.
The film im using is a Kodak Portra 160 4x5 sheet. No i don't have a correction profile.

9034090341

i will give all your suggestions a try.

THank You

Larry Gebhardt
28-Feb-2013, 12:38
Your print scan looks really washed out. You didn't post it with an embedded color profile, but my guess is the original is in a wide gamut, but the browser assumes sRGB. Can you compare the posted images (in the browser) with your originals.

But looking at your scan it looks like you don't have much clipping of either the highlights or the shadows. A simple levels to adjust the color balance and a curve to adjust the exposure brings it very close to the print (assuming it is in ProPhoto). I'll PM you to get your address to send the PSD to.

abc123kazu
28-Feb-2013, 13:51
Hey Larry. Thank you for the help. The point wasn't that i was trying to get somebody to fix it for me but for me to find a fix and a solution going forth. That's why i posted lo-res as a point so you can understand the color shifts i am getting. Another thing i was trying to figure out was if this is something to be adjusted during scan, or perhaps my scanner is already broken...
Either way, thank you so much i will send you the email address.

Light Guru
28-Feb-2013, 14:46
Thank You everybody for the response. Here is the jpegs of both the scan of prints vs the color negative scan.
The film im using is a Kodak Portra 160 4x5 sheet. No i don't have a correction profile.

9034090341

i will give all your suggestions a try.

THank You

I pulled your negative scan into photo shop and did a simple color balance adjustment and it looks better then both your raw scans.

it was a simple 2 second adjustment.

90348

abc123kazu
20-Mar-2013, 08:49
Thanks Zak. Yes this is a temporary fix but i wonder what the problem is with the scanner... it does scan prints correctly but transparent with a blue hue...
could something be wrong with the scanner

tigger_six
20-Mar-2013, 09:03
Thanks Zak. Yes this is a temporary fix but i wonder what the problem is with the scanner... it does scan prints correctly but transparent with a blue hue...
could something be wrong with the scanner

The scanner is likely alright. It's most likely a problem of different film base color. The film base is almost certainly orange/yellow so if inverted, it will be blue. If the film base changes (for instance the new portra has different film base than the old one), you need to subtract different amount of blue from the colors. Because of this, you always have to make color correction to a negative, unless the base is fully transparent and colorless.

Light Guru
20-Mar-2013, 09:06
Thanks Zak. Yes this is a temporary fix but i wonder what the problem is with the scanner... it does scan prints correctly but transparent with a blue hue...
could something be wrong with the scanner

Its probably your scan settings.

abc123kazu
20-Mar-2013, 09:19
i guess the scanner gotta go~

Light Guru
20-Mar-2013, 09:48
i guess the scanner gotta go~

I didnt say it was as the physical scanner, I said the scanner settings. Most of scanning is the settings that you use in the software that tell the scanner what to do.

SergeyT
20-Mar-2013, 18:18
I think that first of all you should upgrade your LinoColor to version 6.x to take advantage of ICC support and as the next step to profile your scanner using an IT8 or other suitable target and software

abc123kazu
25-Mar-2013, 16:13
sorry i didnt see the second page. At this point, is it still possible to get version6?

Thank You

polyglot
26-Mar-2013, 02:53
Note the blueness is in the shadows not the highlights; the problem is that you've set the black-point incorrectly. Have a read of the C41 scan howto in my FAQ (link in signature) that explains this.