Help needed with Nikon CoolScan V ED settings

[Dieguito]

Hello,

I usually work with Fuji Sensia 200 film, but recently I tried Agfa XRG 200
film. I scan my pic's afterward with my Nikon CoolScan V ED.

If one looks at the images on http://dieguito.port5.com/XRG200.jpg, a
problem that I never have with my Fuji film becomes clear.

The left image is the result from the lab (on paper, scanned with a cheap
flat-bed scanner), where as the right image is scanned with my Nikon
scanner. I never had problems with my scanner before, scanned images are
usually quite resembling to the printed pic's.

I've tried to improve my result with the variations tool from PhotoShop (not
visible in the image from the link). I got it an end in the good direction,
but I still wasn't satisfied. I'm also sure that it is because of the Agfa
film, because the entire film has weak colors and rescanning an older
Fuji-film is still ok (so it isn't the scanner).

I'm convinced that I can make the result better (if the lab can, why
wouldn't I), but I don't know how to set up my scanner. I've posted this
question before on another news group and someone there told me that it
probabely was because of the auto exposure, so I switched it off, but now I
find no reference to base the exposure on. (Unfortunately I didn't made a
gray image to do so). I can't use other images from the film, because the
problem occurs on every picture and I can't use my usual Fuji film because
the orange color mask is (obviously) different from the Agfa film.

Can anyone help me out on that?

Thanks a lot,

Dieguito

 

[Roger S.]

I don't know Nikon scan, but is there anything to disable auto color
correction or auto white balance so that you get to see what's on the
film?

Exposure for negative film should be pretty constant for every frame,
so one value should generally work.
Try scanning the clear negative film leader. If you do a search on
this group, you can find an advanced workflow by Erik Krause to set the
exposure for each channel to give you neutral results. I can't
remember if it worked with both Vuescan and Nikonscan.

 

[Don]

I'm convinced that I can make the result better (if the lab can, why
wouldn't I), but I don't know how to set up my scanner. I've posted this
question before on another news group and someone there told me that it
probabely was because of the auto exposure, so I switched it off, but now I
find no reference to base the exposure on. (Unfortunately I didn't made a
gray image to do so). I can't use other images from the film, because the
problem occurs on every picture and I can't use my usual Fuji film because
the orange color mask is (obviously) different from the Agfa film.

First of all, turning Auto Exposure off in NikonScan is *very messy*!.
You have to turn it off in *all* places: preview, positive and
negative... Secondly, you have to turn the scanner *off*. Only then
will the Auto Exposure really, truly be off.

However, once you restart if at *any time* you click on the auto
exposure button *manually*, it's on again!!! That means, you have to
exit NikonScan and turn the scanner off before it's gone.

That's because once an Auto Exposure measurement is made it's saved
*within the scanner*. Any exposure setting after that (using Analog
Gain) are applied to this base setting!

Once you have really turned auto exposure off, the way to set it
correctly is to look at the histogram (Curves display). Adjust Analog
Gain until the histogram touches the right edge.

BTW, not much can be concluded from your example because there are too
many unknown variables in the chain (flatbed, printing, etc).

Don.

 

[Dieguito]

I don't know Nikon scan, but is there anything to disable auto color
correction or auto white balance so that you get to see what's on the
film?

Exposure for negative film should be pretty constant for every frame,
so one value should generally work.
Try scanning the clear negative film leader. If you do a search on
this group, you can find an advanced workflow by Erik Krause to set the
exposure for each channel to give you neutral results. I can't
remember if it worked with both Vuescan and Nikonscan.

I tried the film leader before, but the problem is that the scanner thinks
that's "average gray", so the result is overexposed.
I've tried the VueScan trial and used it's film type settings. The results
are satisfactory for most pic's, but the sunset is still a pain in the butt
(although the results are much better already).

Thanks for the help,

Dieguito

 

[Dieguito]

Once you have really turned auto exposure off, the way to set it
correctly is to look at the histogram (Curves display). Adjust Analog
Gain until the histogram touches the right edge.

BTW, not much can be concluded from your example because there are too
many unknown variables in the chain (flatbed, printing, etc).

Don.

Don,

I've managed to get rid of the auto exposure, but I can't manage with the
analog gain. The histogram with the default settings already touches the
right edge, but not the left edge. The colors are still mixed up and every
time I change the analog gain settings, the histogram is totally different.

I guess I must be stupid and I'm pretty stressed on this, but if you take a
look at the other branch of this thread, you'll find out I got the rest of
the film pretty ok with VueScan.

Thanks for replying anyway,

Dieguito

 

[Don]

Don,

I've managed to get rid of the auto exposure, but I can't manage with the
analog gain. The histogram with the default settings already touches the
right edge, but not the left edge. The colors are still mixed up and every
time I change the analog gain settings, the histogram is totally different.

Hi Dieguito,

First of all don't worry about the left histogram edge. Those are the
dark areas of the image. You actually *want* the histogram of a raw
scan to move away from there!! This is because any data on the extreme
far left side is full of noise (too complicated to explain in detail)
and there is very little actual image data in the first few histogram
bins. Depending on a lot of factors (like gamma, film type, etc) the
first 10-15 bins on the left usually contain no usable data. Later on,
when you start editing this image, you would normally set the black
point to about that value and clip anything below it.

BTW, it's perfectly normal that the histograms would change as you
change analog gain. Don't worry about that, but just try to get the
histogram as close to the right edge as you can. That will give you
the most dynamic range, so you will have the most flexibility when you
edit the image later. You can even "clip" the right edge a little
because some of those extreme highlights are often blown anyway.

I guess I must be stupid and I'm pretty stressed on this, but if you take a
look at the other branch of this thread, you'll find out I got the rest of
the film pretty ok with VueScan.

As I mentioned before, Vuescan does a lot for you in its automatic
mode, but it also does a lot of damage. How important this is depends
on your requirements. Some people are perfectly happy with Vuescan's
output. Others, who actually analyze the data, don't like this damage
and all the Vuescan bugs and unreliability. Also, the image you get
from Vuescan is heavily edited (one reason for the corruption) while
what you get from your scans above is a raw image. This image still
needs to be edited afterwards.

Thanks for replying anyway,

My pleasure! I hope it works out for you. If you continue to have
problems keep asking because there's usually someone here who can help
out. Even with Vuescan there are many long time users happy to lend a
hand.

Don.