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fishbulb
2-May-2015, 10:53
I'm having some difficulty scanning color negatives with my Howtek 4500.

It would be great to hear about your workflow for scanning color negatives with DPL.

My current workflow:

* DPL 7.8 non-pro, Howtek 4500, mostly scanning Kodak Portra 4x5 or black and white
* Wide gamut negative uncorrected, 4000 dpi, optical only, AutoTrack aperture
* Acquire 4500
* Preview scan
* Select each 4x5
* Detail scan each
* Open histogram on each detail scan
* Do my best to tweak the color channels of the histogram get the color looking "right", which sometimes seems impossible, even with "auto adjust" or the grey point eyedropper
* Add all four 4x5's to batch, start batch
* Open .tiffs in Photoshop, do my best to fine-tune the color balance, which sometimes seems impossible

I have the full-length DPL manual from Aztek (90 pages) and they talk about the "Negative Analyzer" being helpful for color neg scanning. Does anyone use this? Or do you use the pre-made Aztek film profiles instead of "wide gamut negative uncorrected"? Any ideas on workflow for getting accurate color in general?

Here is an example of one of my more troublesome scans. Scan (wide gamut negative with histogram adjustment), then the photoshop-tweaked version, then a "final" cropped version.

I realize it's not the best photo in the world, but it's a good example for this, where the original scan often has a weird color cast, or looks foggy and low-contrast, or I just can't get the colors to balance right - if the shadows look good, then the midtones look wrong, etc.

133276 133277 133278

Lenny Eiger
2-May-2015, 12:07
Adam,

A few things.

From the look of that scan, I'd be upset as well. Your correction is only half the way there. It should look like the second image, at least.

1) Do not AutoTrack. Set the aperture to 13 or 19, set a small zone, say .2 by .2, detail it, and look at which is best and set that to aperture setting. Then set the dpi to 4000.

2) Forget the stupid eyedroppers. Look at the image. The eyedroppers don't work. There is nothing automatic about correcting, unless the Autocorrect senses everything just right, which is very rare. (By extension, forget the Negative Analyzer, setting little points in the image to track, etc.). Remember that the guys at Aztek are engineers, not photographers.

3) Auto Adjust can give you a starting point, and it often gives me an idea of what cleaner color (than what I was imagining) looks like. However, Histogram correction is only a very rough beginning. I can't stress this enough. For all negatives, you have to go into Curves. It may be a little hard at the beginning but it gets easier, and then you can't imagine why you scanned anything without it. Don't forget to walk away from the monitor, then come back and look again once in a while... your eyes can get way off track, imagining you are "correcting" something.

I use Wide Negative Uncorrected for Negs, as I am using Pro and using the Custom CMS option. Regardless, that works best for me. Unless I am doing chromes, then their Generic Chrome ICC Calibrated is almost always a great start.

If you have a DPI Enabled optical setting, use that as well, I don't remember if the 4500 has that...

Good luck,

Lenny

P.S. If after all that, you are still having issues, call me, and I'll try and help.
707-763-5922

fishbulb
2-May-2015, 16:33
OK thanks Lenny, I will give that a try and read up on the curves stuff in the DPL manual. Thanks for the help!

axs810
2-May-2015, 19:35
What Lenny said for #3 is important. When scanning adjusting the histogram and curves are an important two step process. Make sure you are using the densitometer when making all these adjustments. Adjust the histogram but make sure nothing is clipping, then make a curves adjustment and again make sure nothing is clipping (I keep it 10-20 points before clipping so when making final adjustments in PS I have some play room with the negative). Then take it into photoshop and give it slight corrections.

Custom CMS option is also a good workflow to get into as well.


edit/ Also use the film rebate to get a neutral color balance for the blacks. On my monitor I'm seeing a color cast in the shadow areas of your examples. (could be my bad though because I haven't calibrated my monitor for 6 weeks.)