7600i color stability

[bframe5]

Has anyone had any issues with color stability?
If I scan the same shot multiple times, the color changes with every scan.
This makes it very difficult to use this scanner to process rolls of film shot in controlled lighting conditions, where color consistency is necessary.

For the testing I disabled everything that I possibly could.

Film: Kodak Portra 400 VC
No dust removal/correction.
No negafix or CCR applied.
No other corrections.

Test 1

Test-1.png (130.35 KiB) Viewed 1916 times

This was scanned at 1:43AM. (Converted to PNG for forum uploading.)

Test 2

Test-2.png (130.4 KiB) Viewed 1916 times

This was scanned at 1:44AM. (Converted to PNG for forum uploading.)

Lightroom3 histogram

Histogram.jpg (57.73 KiB) Viewed 1916 times

Here you can see that the Lightroom3 histograms are VERY different.
Any ideas? Should I be sending in my scanner for warranty repair/replacement?

[LSI_Ketelhohn]

Dear customer,

was the device at a constant temperature when you made these scanns?
It takes about 20 min of contious scanning to reach the final color values of a scanner.
I assume the scan frame did not change?
Did you deactivate the CCR and auto functions in NegaFix?
(in an Ai version the "auto" selector is located in the advanced NegaFix settings)

kind regards,
Arne Ketelhohn.

[bframe5]

Thanks for the reply!

I tried scanning for 1 hour straight, and the colors stabilized after around 30 minutes.
I'm happy that the colors are correct, but a bit disappointed that a LED-based film scanner takes 30 minutes to stabilize.

[LSI_Morales]

Dear bframes

all scanners change temperature, especially when you start it after hours of not being used. Apart from this fact, scanners can not produce exactly the same result because the amount of electricity and the pixels are not always the same in the same position, these variations produce the subtle differences you have observed.
The best way to achieve similar results is by doing the scans after achieving the optimal working temperature of your device. Constant scanning after this temperature has been achieved also helps.
If you have your device close to a source of fresh air, this might also produce temperature changes which might affect your scanner.

Cheers