Image manipulation in Vuescan or in photoshop ?

Hi,

 

I'm a beginner who has just bought a CanonFS40000 scanner. I'm using

it with Vuescan software. It is not clear to me weather I should do

the image manipulation(contrast, color correction)in Vuescan or in

the Photoshop programme which I use as viewer. Does it make any

difference ? Thanks in advance for your views.

If you manipulate the data file (the image ) in the scanner software you never

have a "clean" orginal to go back to. Having an unmanipulated image stored

somewhere (hard drive or CD-R) is just a very good idea for many reasons,

especially if you are not working with a monitor you know to be accurate in the

first case.

I agree with Ellis, but that's not to say that you should just punch the button in VueScan and take whatever comes out. You want a "neutral" scan, and that will virtually always mean you will be manipulating VueScan to set white and black points, and correct color casts.

While what Ellis says is generally easier, it isn't a good idea. If you leave your manipulation to post scan, you will usually end upwith a lower quality image. Adjusting white and black points, and making use of the "Lock Exposure" feature will allow you to obtain much better scans with a full histogram. If you choose to adjust these thing later in Photoshop, you'll see that your histogram becomes considerably stretched, indicated by the "spikes."

 

This also brings in why you might want to scan at 16 bit color (per channel). You have more information to work with and it'll result in a smoother image and you'll have a smaller chance of stretching your histograms too far.

 

Color correction is fairly easy to do in vuescan as well, and I suggest taking that route. Also check out the preset color adjustments he has, and try the film profiles (Kodak mainly). Some are more useful than others it seems.

When I do the initial, physical scan in Vuescan, I only save the raw file. I do no cropping (use maximum setting). Subsequently, I "Scan from Disk" using the raw files, cropping and doing adjustments as follows. In the case of color slide I do all my adjustments in Vuescan (except rotation), with b/w negs. I innvert, clip and convert to grey scale (and rotate as necessary) in photoshop.

 

If any of the results are not satisfactory, either exposure wrong or mis-cropped, I can rescan from disk. I don't have to put slide/neg. back in carrier.

 

Check out the use of "=", as opposed to "+" to append output file name, in Vuescan. With "=", the file name will match the frame number, as opposed to being the next available number.

 

When scanning from disk, be sure to set Device|Scan Mode to your scanner, not transparency.

 

In the case of color slides, I do my entire correction in Vuescan. With black and white I do some post scan adjustments in photoshop. I've been scanning with the following settings:

 

++++

 

Color slides (Fuji provia 100):

 

Device Tab:

 

Media type: Slide Film

 

Bits per pixel: 48 RGB

 

Color Tab:

 

Slide Vendor: kodak ektachrome

 

Color balance: neutral *

 

Black point (%): 0.02

 

White point (%): 0.02

 

Brightness: 1

 

Slide Curve: log dark

 

All Spaces: sRGB

 

* I find a very few images need "white balance" setting, IF there's an obvious and distracting color cast. However, white balance can take "honest" warmth and vibrancy out of images. I always try neutral first and usually stay with that.

 

++++

 

Black and white (mostly tri-x):

 

Device Tab:

 

Media type: Image

 

Bits per pixel: 48 RGB

 

Color Tab:

 

Color balance: Neutral

 

Black point (%): 0

 

White point (%): 0

 

Image Curve: log dark

 

Brightness: 1

 

All Spaces: sRGB

 

black and white negs. post-scan adjustments in photoshop:

 

Invert (scanning as "image" is giving me reversed tone image)

 

Clip per channel 0.1% bright and dark

 

Convert to grey scale

 

++++

 

With both color slide and b/w negs in photoshop:

 

Convert to 8 bit per channel AFTER completion of all touch-up.

Michael,

 

The only reason to do heavy editing in the scanner software is if you have a scanner that scans in high bit mode (>8 bits/channel), but only produces 8-bit files. In this situation, performing adjustments prior to downsampling to 8-bits retains more image information. Your FS4000 provides 14-bit files, so this is not an issue. As Ellis mentions, having the unadulterated scan is a good idea.