Nikon Coolscan IV


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Phildate

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Hey,

Anyone out there consider themselves an expert with this scanner? I bought one a couple of weeks ago and I am having mixed results. The instruction manual is poor and so scanning is just a time-consuming trial and improvement exercise at the moment.

I am scanning slides and B&W negatives. I have Photoshop 7 and PSP (latest) for post-scan. Can't decide which of these I like best either!

If anyone could tell me how to get the most from this scanner it would be most welcome.

Specific questions: 8 bit or 12 bit scanning? save as TIFF or JPEG?
using ICE seems to degrade colour quality? RBG or CYMK? Is it better to leave brightness and contrast alone and then adjust in PS?

Hope to hear from someone soon.
 

I won't say I'm an expert but this is my usual SOP

turn off everything, except ICE, ICE does not degrade the colors... at least not to me.

ICE don't work with B/W film, unless you're talking about chromogenic films such as XP2 and Tmax400CN

8 bit, JPEG, RGB
 

it's a horrible scanner! quick sell it to me cheap! ;p


on the other hand, you're new to it, shd try reading up on what others do to the scanner on the Net, for adjustments and optimisations etc...

PS: willing buyer, really.
 

Hi Phil,
First suggestion - scan in the HIGHEST input bits possible. Can afford to scan with a lower reso but not lower bits. Reasons are simple - Assume your slide has 1000 different shades of red, scanning in 8 bit means u can only differentiate 256 and others are just approximated with the closest neghbour - so you lose out on full tonality. Second, in general scans have a dmax-dmin range of around 3.4. 8 bit scanning cannot support this complete dmax. While scanning with a higher input bits doesnt guarantee that the entire contrast will be captured, but it is a pre-requisite. And though I cannot explain it, I find that when I scan in 8-bit, the colour sucks.

As for improving colour, try something that I have tried and have succeded with (in my case!) - instead of launching the native software of the scanner directly, launch it via the Twain interface of adobe (File->Import). That does have an effect.

ICE does degrade image quality, so for work that requires high precision, turn it off and use PS7s healing brush to correct dust/scratches. ALWAYS use RGB. Definitely if you are printing at home. Try doing a significant part of the adjustments via scanner - To understand why, consider this - assume you have a slide with brightness range from 0.2 to 3, your scanner can detect a range of 3 but the defaults it detects from are 0.5 to 3.5. So what happens is you capture slide brightness from 0.5 to 3 and the rest is lost. But if you change scanner settings so that its scans from 0.2 to 3.2 (same range of 3), all the details are captured. So do a bulk of correction using scanner software and fine tune in PS. Another suggestion is that you use 3rd pary specialised software like Vuescan and Silverfast instead of native software. They are simply MUCH better. You probably get Silverfast bundled in. Otherwise buy it! After all, you have spent a lot on this expensive piece of hardware - a bit extra on the right software will go a long way in realizing its potential.
 

Hi Phil,

No worries, you can get quickies easily at CS. Quick answers, I mean. ;)

I'm no expert but have some experience in scanning so we can exchange some info here.

Choice of RGB or CMYK depends on your need. If you need your pics to be displayed online, RGB is the one to go for. If you're looking to print out your shots, then use CMYK. This is because RGB are the primary colours for LIGHT whereas CMYK are the main colours for INK. Everyone knows if you mix R, G and B lights, you get white. Try doing that with ink on paper and you'll get some nonsense colour. Not white anyway...

Again, TIFF or JPG depends on what you want out of your scans. JPG is a lossy compression format. This means information is compressed to allow for smaller file size but quality is lost in the tradeoff. TIFF, on the other hand, is a lossless compression format. Information of each pixel is stored individually for TIFF. However, for JPG, the colour average information of a few pixels are combined into one. That's why you get smaller filesize but lousier quality.

For a small print (up to 8R i think), most of us will not be able to tell the difference between a JPG and TIFF printout. For something beyond that region, you will be able to notice.

If it's just to display online, 72ppi JPG file is more than enough. It's lousy enough not to have others steal your work if they choose to copy and paste from your post but sufficient to view. For printing purposes, 300ppi JPG is sufficient. That's the industry standard anyway. However, it'll be ideal if you use RGB for the former and CMYK for the latter.

There are other factors involved when you choose between RGB and CMYK. Things like the colour standards etc are what the printer will (presumably) ask you. If not, you'll notice what you print on paper is not what you see on screen.

Have fun scanning! :)
 

Thanks everyone. All very useful advice. Seem to be getting to grips with it now so I won't be selling cheap!! Sorry!
 

1.I agree with RL on this one: leave ICE on all the time

2. I also agree with RL on this: I also scan into 8-bit TIFFs (or Jpg if not an important image - i.e. will be used at a small size only). The only reason you want to scan into 16-bit TIFFs is if theres an exposure problem and you want the max dynamic range possible to allow you to correct the problem.

3. I routinely use the exposure compensation function on the nikonscan panel for small amounts of exposure tweaking. (+0.1/+0.2 for eg)

4. Save into Adobe RGB, not sRGB.
 

Originally posted by erwinx

4. Save into Adobe RGB, not sRGB.
What's the difference between Adobe RGB and sRGB? :dunno:

Why is Adobe RGB better than sRGB? :dunno:
 

But by scanning 16-bit, I notice certain functions are not possible in Photoshop. Also, I can't tell the difference (on screen at least) between 8 and 16-bit. Is it only apparent after printing?

Where do u get the Silverfast or Vuescan softwares?

Thanks!!!!
 

AdobeRGB and sRGB have different colour gamuts - meaning the colours that they can represent are different. Any colours outside their gamuts are just approximated by the closest or any random colour. Adobe has a wider gamut - so colours that can be differentiated in AdobeRGB gamut are assumed to be the same in sRGB. And I disagree with rayman when he says you must use CMYK while printing. CMYK is only to be used with certain kinds of printers (I believe offset printers etc). For home based ink-jets one must use the RGB and AdobeRGB is better in these cases. For display on web on the other hand, it is better to use sRGB because the monitors typically have a gamute that is closer to sRGB.

Jerome, u are right that most functions are not available in 16-bit. But there are work-arounds to most of functions - so working in 16 bit is seldom a handicap. And in functions that do work on 16-bit, adobe handles things better (smoother histograms etc). In the worst case, one can always convert to 8-bit post scanning and still the colours would be better.
 

Originally posted by Radix Lecti
AdobeRGB and sRGB have different colour gamuts - meaning the colours that they can represent are different. Any colours outside their gamuts are just approximated by the closest or any random colour. Adobe has a wider gamut - so colours that can be differentiated in AdobeRGB gamut are assumed to be the same in sRGB. And I disagree with rayman when he says you must use CMYK while printing. CMYK is only to be used with certain kinds of printers (I believe offset printers etc). For home based ink-jets one must use the RGB and AdobeRGB is better in these cases. For display on web on the other hand, it is better to use sRGB because the monitors typically have a gamute that is closer to sRGB.
Therefore, to summarize:

For home based ink jets printing, it's better to use AdobeRGB.
For web viewing, sRGB is recommended.

Radix, how about for achival purposes and for printing at a lab, which colour gamuts are recommended?

:angel:
 

That is the Million dollar question! I tried asking at the Photo-hub at OUB, but they didn't know anything about colour gamuts. But I believe they use a fuji machine to print and I think (I am definitely not sure) that CMYK is the format that should be used. This is because the method of printing I believe is chemical and not digital based ink-jet printing. But in case you do it at digitally epson square or the likes, again Adobe RGB is recommended.
 

Yup, Those are sites and both give trials to download. Silverfast embeds watermarks into your scans in the trial version whereas if I am not wrong, the ones using vuescan cannot be saved. Silverfast is much more user friendly, but both give good results compared to HP Photosmart's native software.
 

I'm not an expert but here is my curve:
For slides:
1. Call local Kodak office and order Q60 calibration target slide (cost ~ 50 SGD, delivery time ~ 3 weeks)
2. Turn off original color correction and auto exposure and scan test slide.
3. Create scanner profile for your scaner with any type of ICC profile generators (Scarse http://www.scarse.org/, or PhotoCal, or OptiCal http://www.colorvision.com).
4. Scan slides (12 bit/color) w/o original color correction and w/o auto exposure (you can turn ICE on) and assign your ICC profile in PS.
5. Convert profile to your working (I use AdobeRGB) profile.
6. Save original (I prefer original PSD format).
7. do the rest of corrections (convert to 8 bit, levels, curves and so on) in PS and save it.

P.S. my scanner gave me horrible colors w/o calibration (p.1-3) esp. reds, yellows and greens.
 

Originally posted by Radix Lecti
That is the Million dollar question! I tried asking at the Photo-hub at OUB, but they didn't know anything about colour gamuts. But I believe they use a fuji machine to print and I think (I am definitely not sure) that CMYK is the format that should be used. This is because the method of printing I believe is chemical and not digital based ink-jet printing. But in case you do it at digitally epson square or the likes, again Adobe RGB is recommended.

FotoHub at OUB uses a Nortisu QSS series digital minilab.
The Bukit Timah branch uses Fuji Frontier 350/370.
Each has it's own profile, which is available for download (at popphoto.com I think). I have not tried embedding the profile and sending to any of the labs. The files scanned from negatives from a Frontier comes embedded with a sRGB profile. So I won't be surprised if those use sRGB as the colourspace.

I definitely don't think it's CMYK though. Both machines uses laser printing technology to print to traditional colour papers, which is then chemically processed.

Regards
CK
 

Thanks all for the useful websites.

Originally posted by Radix Lecti
Jerome, u are right that most functions are not available in 16-bit. But there are work-arounds to most of functions - so working in 16 bit is seldom a handicap. And in functions that do work on 16-bit, adobe handles things better (smoother histograms etc). In the worst case, one can always convert to 8-bit post scanning and still the colours would be better.

Radix, what do u mean when u say "smoother" histograms? But really, are there any apparent differences betn 8-bit and 16-bit in terms of colours? I read that 8-bit gives 256 colours and 16-bit gives 2 to the power of (what?) which is millions of colours! But I certainly can't tell the difference. Also, 16-bit RAW to TIFF conversion takes up a huge amount of disk space, like close to 20MB?!

BTW, for RAW image conversion, what does the "linear" option mean?

Thanks again!!!
 

hi jerome, the 8 bit here is for shades, per channel not per pixel... i.e. 8 bit x 3 + 8 if u using alpha in TIFF...
16 bit means 65k shades per colour R, G or B... it's overkill sometimes becos u dun really know if ur picture's gamut is actually that high, but it is a "safety". You can't see it unless you have a 48-bit capable printer. Std PC video is still 8 bit, RGBA.
 

hmmmm... just trying... see if this makes sense to u guys

CYMK is for printing purposes as the printing process is a subtractive one, ie, the default colour is white (paper) and the more colours u add, the darker it gets.

RGB is for projection purpose, ie, monitor, 3 gun projector. this is an addition process, ie, if add RGB in correct amount, u get white & the more colours you add, the brighter it gets.

Actually we shouldn't be too worried about the conversion betw RGB(& its variants, sRGB, Adobe RGB) to CYMK. The computer, whether PC or Mac has standard CMM(?) profile and the conversion is pretty non-event and consistent across the board. The common Win OS all have this CMM thingy, accept Win NT.

Also, unless u do your own printing, don worry about CYMK profile either. CYMK profile is affected by ink, paper, and printing process (black cut-off point...) and technology. This is for the labs to worry- if they change the paper and ink, they will have to profile it properly. ie, they may have 10 CYMK profile for 10 diff combinations of paper & ink.

So if you wanna get accurate printing as what u see on your monitor, then get a colour management system.
So in summary, work in AdobeRGB colour space. Send ur files in AdobeRGB to lab. The lab will have to covert to CYMK for printing (non-event).

ermm... makes sense? :dunno:
 

Originally posted by Radix Lecti
And I disagree with rayman when he says you must use CMYK while printing. CMYK is only to be used with certain kinds of printers (I believe offset printers etc). For home based ink-jets one must use the RGB and AdobeRGB is better in these cases.

Hi Radix,

Pls correct if I'm wrong. Don't ink cartridges for printers come in packs of CMYK? Well at least the ones I've come into contact to do. Doesn't this mean that CMYK will be a better representation of the colour scheme to use so as to get a closer version of the actual printout on your monitor?

Thanx for letting me know :)
 

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