Re: filmscanners: VueScan 6.4.x suggestion
Try increasing the preview dpi and see if you get a closer match between vuescan and PS. - Original Message - From: "Gordon Tassi" [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Sunday, January 14, 2001 2:20 PM Subject: Re: filmscanners: VueScan 6.4.x suggestion Ed: I found the same with Vuescan vs. PS 5 for both slides and negatives on my LS-30. I rescanned but with the brightness set at 1.3 for the slide and negative rather than .7. The slide was fine, the negative was OK but with less contrast than the slide. Gordon shAf wrote: Ed makes us aware ... however, what Vuescan shows me and what I end up with in Photoshop is quite different (what being acceptable ends up in PS, Vuescan showing me a darker image). shAf :o)
Re: filmscanners: orange mask
Ilford XP1 developer had different composition to plain C41. The newer XP2 requires C41. ~~ When XP1 film dev was sold by Ilford it was my first choice in developer for all our colour film. We found that the slightly longer dev time of 5 minutes and the presumably accurate chemistry makeup gave superb consistency. "Don't worry about the world coming to an end today. It's already tomorrow in Australia".
RE: filmscanners: orange mask
At 07:37 13/01/2001 -0800, you wrote: Improper film storage and handling prior to processing plays a big part in the consistency of color and density characteristics of the orange mask. not exactly. what you call the orange mask is in reality the mask plus an unwanted image. properly stored films precessed in proper manner have correct mask plus very low fog. if you bugger storage and/or processing then you increase the fog. remember the mask is there to compensate for not-so-ideal spectral properties of the formed dyes. if we treat the fog and the image as "positive" density, the mask will be "negative". you deal with two images dependent of themselves and superimposed. Also when referring to the word "lot" are you speaking of same film type but different batch or are you referring to Kodak versus Fuji? Different film types (Kodak, Fuji) will definitely show visual differences in the orange mask. Also different ISO ratings have differences as well. the color of the mask depends on used components, which vary from manufacturer to manufacturer and/or film. it is however possible to have films with identical mask, even from different manufacturers. it depends, what they put into a kettle. Bear in mind that it is not important, how does the mask look to your eye, but how the paper emulsion sees it. and for the paper the differences may be negligible. Paul Problem is that the color characteristics of the orange mask vary -- from one film lot to another, and in particular, as a function of the processing of the film. [rafe b:] I can't say for certain, but my gut (and my eyes) disagree with you. Plus, I have heard this from others. I'd be curious to hear other folks' experiences and thoughts on this. http://okphoto.webjump.com P:250-498-2800 F:250-498-6876 "Don't worry about the world coming to an end today. It's already tomorrow in Australia".
Re: filmscanners: orange mask
At 11:52 12/01/2001 -0800, you wrote: http://www.zocalo.net/~mgr/DigitalPhoto/derCurveMeister/index.htm 404 - not found "Don't worry about the world coming to an end today. It's already tomorrow in Australia".
Re: filmscanners: VueScan 6.4.x suggestion
Try increasing the preview dpi and see if you get a closer match between vuescan and PS. A few days ago Ed told this list that the Preview will rarely match the scan. Once I found out that the Preview in Vuescan was supposed to be different than in the other scanning software I have used it has made using Vuescan easier. I now use the Preview *only* for cropping since all other results are unreliable. Here is what I do -- I know it is a real pain: 1. Do a Preview. 2. Crop. 3. Scan using a a medium resolution. 4. Make adjustments on the Color tab, scan from memory, make adjustments, etc. I iterate through this until I get a result that I like. Each time the image is going to Vueprint so I can check the histogram and also so I can get a bigger image. 5. When I am satisfied with the results of #4 I then reset the resolution to the highest and do the final scan. I have been doing this for about 10 days because that is when I learned that the Preview couldn't be used for anything but cropping. In effect I do two previews. The first one using the Preview button is used for cropping and the second one using the Scan button is used for other adjustments. It slows things down and means doing three scans, but the final scan doesn't surprise me anymore. Naturally, it would be great if the Preview really was an accurate representation of the final scan. Maybe in the future? Henry http://www.bigfoot.com/~hrich _ Get your FREE download of MSN Explorer at http://explorer.msn.com
Re: filmscanners: Re: So it's the bits?
On Sat, 13 Jan 2001 13:18:46 +1100 Julian Robinson ([EMAIL PROTECTED]) wrote: http://www.klt.co.jp/Nikon/Press_Release/ls-4000.html ... Density range 4.2 Hmmm. Except the omission of the word 'optical' is slippery, wibbly-wobbly and misleading - and doubtless deliberate. 'Optical' would tie performance to film. By itself 'Density Range' can mean anything - some internal ability of the scanner, real or theoretical. And that's misdirection, getting the punter to see what they want to see instead of what's there. Regards Tony Sleep http://www.halftone.co.uk - Online portfolio exhibit; + film scanner info comparisons
Re: filmscanners: Fw: Color Profiles for Printers was scanners
On Sat, 13 Jan 2001 13:04:42 -0500 rafeb ([EMAIL PROTECTED]) wrote: Say what??? There's no reason at all that the box of 50 crayons could represent a far wider gamut than the 100 crayons in that "other" box. I think I know what you meant to say, but this was not a particularly precise way of putting it! Sheesh! You guys are sooo picky! :) I thought it was a neat and brief analogy, based on real-life experience of real crayons g Regards Tony Sleep http://www.halftone.co.uk - Online portfolio exhibit; + film scanner info comparisons
RE: filmscanners: SS4000 and Insight/Vuescan software ?
Stan, Vuescan does embed the selected Adobe RGB profile but Insight 4.5 will not. Insight will only embed the monitor profile for 8 bit scans or a special scanner slide or negative profile for high bit scans( I do the latter). So, when an Insight scan arrives in Photoshop, it is embedded with a profile different from your chosen Adobe RGB and, therefore, it asks you if you want to convert. But, the next version of Insight(v5 coming soon)will supposedly be able to embed profiles. Bill Twieg -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Stan Schwartz Sent: Saturday, January 13, 2001 9:22 PM To: [EMAIL PROTECTED] Subject: filmscanners: SS4000 and Insight/Vuescan software ? When I use the SS4000 with the Insight software and I use the Adobe1998 setting in Insight, Photoshop still asks me if I want to convert the image to Adobe 1998. When I use VueScan with Adobe1998 selected, I don't get the "ask when color profile mismatch" box when opening the image in Photoshop. A second question is: is there a VueScan plugin for Photoshop so that it will appear on the File/Import scanner menu? Stan Schwartz http://home.swbell.net/snsok
RE: filmscanners: Re: So it's the bits?
On Fri, 12 Jan 2001 18:21:18 -0500 Austin Franklin ([EMAIL PROTECTED]) wrote: The scanner manufacturers use Dmax as a specification item Used by itself like this, it would be a statment of noise level - ie any higher DMax will be lost in noise, it being below the scanners ability to discriminate. But I think Leaf probably meant to say OD range = 3.7, as most mfr's specify this parameter, meaningless though it is without qualification. Regards Tony Sleep http://www.halftone.co.uk - Online portfolio exhibit; + film scanner info comparisons
RE: filmscanners: Re: So it's the bits?
On Sat, 13 Jan 2001 13:19:01 +1100 Julian Robinson ([EMAIL PROTECTED]) wrote: Nikon may argue that their Dmin is measured with the exposure set low, and Dmax with the exposure set as high as possible. This means that they can get up to another 2 to 4 stops(!!!) into their claimed DENSITY RANGE. Which might explain why they use the term Density Range and not Dynamic Range - Dynamic Range certainly means the range that can be covered without changing the setup i.e. the range available at one instant. Hm. Well spotted! Regards Tony Sleep http://www.halftone.co.uk - Online portfolio exhibit; + film scanner info comparisons
RE: filmscanners: orange mask
Bear in mind that it is not important, how does the mask look to your eye, but how the paper emulsion sees it. and for the paper the differences may be negligible. So would one be wrong to interpret what you are saying here in a fashion as to infer that it might be generally said that these films with their orange masks, whatever the differences, are optimized for traditional photographic printing on photographic papers and emulsions using chemical processes where the mask has little bearing on the outcome except maybe to add some time to the processing and some contrast to the outcome and may not be optimized for digital scanning and processing where the mask may come into more play as a factor in effecting the final printed outcome? Or put another way, the differences under the traditional chemical methods are intended to be negligible; but not so under digital methods where the scanner can be assumed to be like your eye and not like a paper emulsion? -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Roman Kielich Sent: Sunday, January 14, 2001 4:20 AM To: [EMAIL PROTECTED] Subject: RE: filmscanners: orange mask At 07:37 13/01/2001 -0800, you wrote: Improper film storage and handling prior to processing plays a big part in the consistency of color and density characteristics of the orange mask. not exactly. what you call the orange mask is in reality the mask plus an unwanted image. properly stored films precessed in proper manner have correct mask plus very low fog. if you bugger storage and/or processing then you increase the fog. remember the mask is there to compensate for not-so-ideal spectral properties of the formed dyes. if we treat the fog and the image as "positive" density, the mask will be "negative". you deal with two images dependent of themselves and superimposed. Also when referring to the word "lot" are you speaking of same film type but different batch or are you referring to Kodak versus Fuji? Different film types (Kodak, Fuji) will definitely show visual differences in the orange mask. Also different ISO ratings have differences as well. the color of the mask depends on used components, which vary from manufacturer to manufacturer and/or film. it is however possible to have films with identical mask, even from different manufacturers. it depends, what they put into a kettle. Bear in mind that it is not important, how does the mask look to your eye, but how the paper emulsion sees it. and for the paper the differences may be negligible. Paul Problem is that the color characteristics of the orange mask vary -- from one film lot to another, and in particular, as a function of the processing of the film. [rafe b:] I can't say for certain, but my gut (and my eyes) disagree with you. Plus, I have heard this from others. I'd be curious to hear other folks' experiences and thoughts on this. http://okphoto.webjump.com P:250-498-2800 F:250-498-6876 "Don't worry about the world coming to an end today. It's already tomorrow in Australia".
re: filmscanners: VueScan 6.4.x suggestion
On my scanwit, and I would speculate that other none exposure adjusting scanners as well, the preview and the scan image are very close. Close enough to use preview mem while adjusting color settings to get an image that is great in PS and requires very little tweaking. alan I have been doing this for about 10 days because that is when I learned that the Preview couldn't be used for anything but cropping.
Re: filmscanners: Vuescan problems
Upgraded to 6.4.8 and it solved the dark scan problem (see posting to Ed Hamrick). Tony Sleep wrote: On Fri, 12 Jan 2001 20:52:29 -0800 John Hinkey ([EMAIL PROTECTED]) wrote: I too have experienced the same exact problem with my SS4000. I'm running version 6.4.1. Like you slide scanning is perfectly normal. I thought it was just me having a setting somewhere out of wack, but the last few negatives I've scanned were VERY dark - thus requiring the brightness to be set something like 50 or so. The resulting scan is useable with a lot of tweeking in Vuescan and Photoshop. The negative looks pretty well exposed. Are you trying to get 8bit/channel scans out, or 16bit? This sort of thing is pretty normal for 16bit, you'd expect to have to adjust levels in PS. I'm using (ancient!) 6.4.5 here with a Pol4000 for 16bit colour neg output, and it seems fine. Regards Tony Sleep http://www.halftone.co.uk - Online portfolio exhibit; + film scanner info comparisons -- John Hinkey Seattle, Washington [EMAIL PROTECTED]
Re: filmscanners: SS4000 and Insight/Vuescan software ?
When I use the SS4000 with the Insight software and I use the Adobe1998 setting in Insight, Photoshop still asks me if I want to convert the image to Adobe 1998. When I use VueScan with Adobe1998 selected, I don't get the "ask when color profile mismatch" box when opening the image in Photoshop. Are you using a mac? A friend with a SS4000 on a mac has this problem. His system should have been giving ColorMatch profile, but Insight declared it sRGB. I don't know how it was resolved, nor if it was an Insight problem or system problem (he had to do a number of system repairs); but it's something to check for. -- Bob Shomler http://www.shomler.com/gallery.htm
Re: filmscanners: orange mask
Roman, Ilford XP1 developer had different composition to plain C41. The newer XP2 requires C41. You _could_ use C41 with XP1, but Ilford recommended their own special XP1 developer for best results. They now seem to have stopped selling special developer for XP films and say you should use ordinary C41. Brian Rumary, England http://freespace.virgin.net/brian.rumary/homepage.htm
RE: filmscanners: SS4000 and Insight/Vuescan software ?
Here's what the Help file from Insight says: "Embedding Color Profiles With PolaColor Insight software, you can embed a color profile (information about the image color space) within your image file. Color profiles produce more accurate colors when files are printed or viewed with applications conforming with ICM standards. Adobe Photoshop software (version 5) is an example of such an application. Enable color profile embedding by clicking the Embed Color Profile box when choosing a filename for a scanned image. The profile embedded is the output profile, the same one used to create your image file. " This is version 4.5. I read that to mean it should be embedding the profile. Stan Schwartz http://home.swbell.net/snsok -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of B.Twieg Sent: Sunday, January 14, 2001 8:23 AM To: [EMAIL PROTECTED] Subject: RE: filmscanners: SS4000 and Insight/Vuescan software ? Stan, Vuescan does embed the selected Adobe RGB profile but Insight 4.5 will not. Insight will only embed the monitor profile for 8 bit scans or a special scanner slide or negative profile for high bit scans( I do the latter). So, when an Insight scan arrives in Photoshop, it is embedded with a profile different from your chosen Adobe RGB and, therefore, it asks you if you want to convert. But, the next version of Insight(v5 coming soon)will supposedly be able to embed profiles. Bill Twieg -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Stan Schwartz Sent: Saturday, January 13, 2001 9:22 PM To: [EMAIL PROTECTED] Subject: filmscanners: SS4000 and Insight/Vuescan software ? When I use the SS4000 with the Insight software and I use the Adobe1998 setting in Insight, Photoshop still asks me if I want to convert the image to Adobe 1998. When I use VueScan with Adobe1998 selected, I don't get the "ask when color profile mismatch" box when opening the image in Photoshop. A second question is: is there a VueScan plugin for Photoshop so that it will appear on the File/Import scanner menu? Stan Schwartz http://home.swbell.net/snsok
RE: filmscanners: Re: So it's the bits?
Nikon may argue that their Dmin is measured with the exposure set low, and Dmax with the exposure set as high as possible. This means that they can get up to another 2 to 4 stops(!!!) into their claimed DENSITY RANGE. Which might explain why they use the term Density Range and not Dynamic Range - Dynamic Range certainly means the range that can be covered without changing the setup i.e. the range available at one instant. Hm. Well spotted! Tony Sleep But they *do* use Dynamic Range in some of their literature (4.2 in Nikon's product data sheet for the 4000 ED and their model comparison sheet, provided by Nikon at this past week's Mac World).
RE: filmscanners: Re: So it's the bits?
Dynamic Range certainly means the range that can be covered without changing the setup i.e. the range available at one instant. It depends on what you mean by 'changing the setup'. Dynamic range is a system measurement. If the system can provide a particular 'dynamic range' by doing, say, three passes, and varying the input range of the A/D converter therefore taking three measurements, that would certainly expand the dynamic range of the systems output.
RE: filmscanners: SS4000 and Insight/Vuescan software ?
Yes, it is supposed to embed these profiles for 8 bit scans, and in preferences it allows you to choose either the display profile or "other". Under "other" there is only a Kodak profile and an Epson 1200 profile(my printer). I once figured out how to add a custom version of Adobe RGB space, but it didn't work properly anyway. When the beta version of PCI 5 was briefly posted, I did try that and it was easy to embed profiles with it. With 12 bits per channel scans, PCI will embed either a color slide or color negative profile, and Photoshop will convert to my Adobe RGB space. I have been happy with that. Bill -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Stan Schwartz Sent: Sunday, January 14, 2001 9:43 AM To: [EMAIL PROTECTED] Subject: RE: filmscanners: SS4000 and Insight/Vuescan software ? Here's what the Help file from Insight says: "Embedding Color Profiles With PolaColor Insight software, you can embed a color profile (information about the image color space) within your image file. Color profiles produce more accurate colors when files are printed or viewed with applications conforming with ICM standards. Adobe Photoshop software (version 5) is an example of such an application. Enable color profile embedding by clicking the Embed Color Profile box when choosing a filename for a scanned image. The profile embedded is the output profile, the same one used to create your image file. " This is version 4.5. I read that to mean it should be embedding the profile. Stan Schwartz http://home.swbell.net/snsok -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of B.Twieg Sent: Sunday, January 14, 2001 8:23 AM To: [EMAIL PROTECTED] Subject: RE: filmscanners: SS4000 and Insight/Vuescan software ? Stan, Vuescan does embed the selected Adobe RGB profile but Insight 4.5 will not. Insight will only embed the monitor profile for 8 bit scans or a special scanner slide or negative profile for high bit scans( I do the latter). So, when an Insight scan arrives in Photoshop, it is embedded with a profile different from your chosen Adobe RGB and, therefore, it asks you if you want to convert. But, the next version of Insight(v5 coming soon)will supposedly be able to embed profiles. Bill Twieg -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Stan Schwartz Sent: Saturday, January 13, 2001 9:22 PM To: [EMAIL PROTECTED] Subject: filmscanners: SS4000 and Insight/Vuescan software ? When I use the SS4000 with the Insight software and I use the Adobe1998 setting in Insight, Photoshop still asks me if I want to convert the image to Adobe 1998. When I use VueScan with Adobe1998 selected, I don't get the "ask when color profile mismatch" box when opening the image in Photoshop. A second question is: is there a VueScan plugin for Photoshop so that it will appear on the File/Import scanner menu? Stan Schwartz http://home.swbell.net/snsok
RE: filmscanners: SS4000 and Insight/Vuescan software ?
I am using a PC. Stan Schwartz http://home.swbell.net/snsok -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Bob Shomler Sent: Sunday, January 14, 2001 10:40 AM To: [EMAIL PROTECTED] Subject: Re: filmscanners: SS4000 and Insight/Vuescan software ? When I use the SS4000 with the Insight software and I use the Adobe1998 setting in Insight, Photoshop still asks me if I want to convert the image to Adobe 1998. When I use VueScan with Adobe1998 selected, I don't get the "ask when color profile mismatch" box when opening the image in Photoshop. Are you using a mac? A friend with a SS4000 on a mac has this problem. His system should have been giving ColorMatch profile, but Insight declared it sRGB. I don't know how it was resolved, nor if it was an Insight problem or system problem (he had to do a number of system repairs); but it's something to check for. -- Bob Shomler http://www.shomler.com/gallery.htm
RE: filmscanners: SS4000 and Insight/Vuescan software ?
What is odd is that when I open the image in Photoshop, I get this message: The document's embedded color profile does not match the current RGB Working space: Embedded: Adobe RGB (1998) Working: Adobe RGB (1998) Version 4.5 of Insight Stan Schwartz http://home.swbell.net/snsok -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Tony Sleep Sent: Sunday, January 14, 2001 8:48 AM To: [EMAIL PROTECTED] Subject: Re: filmscanners: SS4000 and Insight/Vuescan software ? On Sat, 13 Jan 2001 23:22:10 -0600 Stan Schwartz ([EMAIL PROTECTED]) wrote: When I use the SS4000 with the Insight software and I use the Adobe1998 setting in Insight, Photoshop still asks me if I want to convert the image to Adobe 1998. Which version? I think all the 4.5n versions around with CM stuff are betas, and currently have incomplete implementation of profile stuff. If you are producing 8 bit scans via Insight, they ignore any output profile setting and output sRGB regardless. If you produce 16bit, the output has been run against the internal scanner profile, but is untagged. Either way, PS will trigger a conversion to Adobe98 because of the mismatch. Regards Tony Sleep http://www.halftone.co.uk - Online portfolio exhibit; + film scanner info comparisons
Re: filmscanners: VueScan 6.4.x suggestion
Henry, I've been doing the same for quit some time now, but with a small alteration: I like the autonumbering feature if Vuescan a lot but rescanning will not allow it if you output every file to VuePrint (or whatever...) Instead I start with turning OFF the output file before I even do the preview. Then I scan the slide at the desired resolution. I test different settings in VueScan and each time performes an Scan Mem When I'm satisfied with the look within VueScan I switch it on again and do a last scan mem to output the file. This way I can use the fast scan mem to tweak VueScan to best results in a very fast way and I only have to actually scan the slide twice (preview + scan). It still happens from time to time that I have to perform another scan mem after seeing the histogram of the slide.. Thus the workflow is something like 1) Turn output file OFF 2. Do a Preview. 3. Crop. 4. Scan at the desired resolution. 5. Make adjustments on the Color tab, scan from memory, make adjustments, etc. 6. When satisfied, turn output file ON and perform Scan mem. Off course step 5 would be alot easier if there was a histogram tool within Vuescan and a Zoom tool (Just wishing...) For this to work for everyone I guess that Vuescan should support ICM and take it into account when presenting the scanned picture but this is OK for me right now. Johan Henry Richardson wrote: Try increasing the preview dpi and see if you get a closer match between vuescan and PS. A few days ago Ed told this list that the Preview will rarely match the scan. Once I found out that the Preview in Vuescan was supposed to be different than in the other scanning software I have used it has made using Vuescan easier. I now use the Preview *only* for cropping since all other results are unreliable. Here is what I do -- I know it is a real pain: 1. Do a Preview. 2. Crop. 3. Scan using a a medium resolution. 4. Make adjustments on the Color tab, scan from memory, make adjustments, etc. I iterate through this until I get a result that I like. Each time the image is going to Vueprint so I can check the histogram and also so I can get a bigger image. 5. When I am satisfied with the results of #4 I then reset the resolution to the highest and do the final scan. I have been doing this for about 10 days because that is when I learned that the Preview couldn't be used for anything but cropping. In effect I do two previews. The first one using the Preview button is used for cropping and the second one using the Scan button is used for other adjustments. It slows things down and means doing three scans, but the final scan doesn't surprise me anymore. Naturally, it would be great if the Preview really was an accurate representation of the final scan. Maybe in the future? Henry http://www.bigfoot.com/~hrich _ Get your FREE download of MSN Explorer at http://explorer.msn.com
Re: filmscanners: Re: So it's the bits?
Hi Austin. Austin Franklin wrote: If you do the math, you'll find that using a 14-bit A/D on most CCD scanners is kind of silly; in such cases, one LSB generally equates to about 10-50 microvolts of signal. How do you work out this figure? I make it more like 170 microvolts, since most CCDs have a saturation voltage in the region of 2.8 volts. I believe both are wrong. The voltage output range of the CCD has to be matched to the input range of the A/D. Of course it does, but the voltage to toggle the LSB of the A/D, *relative to the maximum voltage from the CCD* is one sixteen thousandth of the CCDs maximum voltage, which is about 170 microvolts. It would be wasteful of dynamic range for a scanner designer not to use the CCD close to its saturation voltage. You can NOT associate the volts/bit of the A/D without knowing the input voltage range of the A/D. And you especially can not associate the volts/bit of the output voltage of the CCD without knowing the circuitry between the CCD and the A/D, and then the A/D capture range. I wasn't even thinking of the input of the A/D, just the voltage relative to the CCD maximum output. I've looked at the data sheets of nearly all the currently available CCD linear array sensors, and they really don't vary that much. They saturate at around 2.8 volts and have a dynamic range of around 5000 to 1, whether they're made by Kodak, Sony or NEC. A/D converters vary more, of course, but I don't see what the input voltage has to do with the usability of a 14 bit output. Any A/D converter that wasn't able to 'see' the voltage required to toggle its LSB wouldn't be of much use. The extra bits also give room for the scanner hardware to take advantage of any improvement in sensor technology that may come along, without a major re-build. A bit of 'future proofing' by the circuit designers. Again, I disagree completely, that is not how the system is designed. The CCD has an output voltage range that is then amplified or attenuated and also voltage shifted to match the input voltage range of the A/D. Yes, that's true, but most A/D converters made specifically for scanner use have programmable gain and offset amplifiers built in. Ref: Analog Devices AD9816 and AD9814, and the Texas Instruments series of scanner A to Ds. Anyway, adding a bit of gain is hardly the basis for an entire design philosophy. "Output of CCD = 2.8 volts, input of A/D converter = 4 volts. Ugh! Add gain of 1.4." That's a no-brainer. And doesn't explain why all the scanner manufacturers are now moving to 14 bits. I don't think it's entirely a marketing numbers game. Regards, Pete.
Re: filmscanners: Fw: Color Profiles for Printers was scanners
Shaf. shAf wrote: .. you at least have to have a slide (or negative) with "gamut problem" colors (e.g., dark saturated blues (cobalt blue), bright saturated yellows). Film isn't very useful in this instance. If you look at Kodak's Q60 against the CIE specification for its colour patches, you'll see that the film has already done irreversible damage to the colour. But there's no need to involve film. Colour lighting gels come in almost any hue and saturation you want, and the maker will supply you with the spectral transmission graph as well. The experiment goes something like this ... you scan an image into a wide gamut color space (save it) and then convert it to a narrower color space. Whoa! Back up a minute. How is the scanner hardware supposed to know that it's scanning into a wide gamut space? As discussed in the other concurrent thread, all that the scanner can do is translate Red, Green, and Blue densities into digitised numbers. The makers don't even tell us what the spectral peaks of the scanner's RGB channels are. Regards, Pete.
Re: filmscanners: orange mask
Hi Robert. "Robert E. Wright" wrote: I've always thought the correct curves were dependant on the image content and attempting to write general curves, even for each roll of film, would not be successful. Colour negative film doesn't vary from second to second as most people seem to think. It used to be printed on photographic paper you know, using the same filter pack for an entire roll, or even an entire batch of film! The technique of starting from a raw scan, and applying a generic correction over multiple frames is the only way to get even colour and density across multi-frame panoramas. Rather than use curves, it's easier to use the levels tool, and align both ends of the red, green, and blue histograms, IMHO. Regards, Pete.
Re: filmscanners: VueScan 6.4.x suggestion
Then I scan the slide at the desired resolution. I test different settings in VueScan and each time performes an Scan Mem When I'm satisfied with the look within VueScan I switch it on again and do a last scan mem to output the file. This way I can use the fast scan mem to tweak VueScan to best results in a very fast way and I only have to actually scan the slide twice (preview + scan). The reason I do a scan at a medium resolution (usually 705 dpi) to test out different settings before doing the final scan at 2820 dpi is because even scanning from memory a 2820 dpi 64 bit RGBI scan can take awhile. The intermediate scan from memory at 705 dpi finishes pretty quickly. I typically do 4-8 of these before I'm ready to do the 2820 dpi scan. _ Get your FREE download of MSN Explorer at http://explorer.msn.com
Re: So it's the bits? (Was: filmscanners: Sprintscan 120nowonB+H web
Hi Julian. It is this last point that is the bone of contention - manufacturers are saying "ours is 14 bits so our density range is 4.2 wow isn't that a good figure", and that is probably crap in the case of the consumer level scanners we are talking about. It MAY be 4.2 but is most likely is much less than that - that is all I am saying ... I think. It's certainly crap if they don't use a special technique like split exposure multi-scanning. All the available CCDs on the market today are limited to a dynamic range of 5000:1 (~12 bits) at normal temperatures. I'm not sure if the upcoming CMOS sensors will do any better. Regards, Pete.
Re: filmscanners: Fw: Color Profiles for Printers was scanners
Hi Ezio, Rodney. Ezio wrote: For RGB printers (and more for other color rendering technologies) this limitation is not any more valid. What I have understood , please correct me if I am wrong or saying no-sense, is : RGB printers 3, 5 , any number of inks ... can combine the colors in a way that is not achievable (by some extension) by the phosphores of the screen. I find it very difficult to believe that any reflective and subtractive output can achieve colour of greater gamut than a self luminous additive system. I've measured my monitor as having a 600:1 brightness range, a good paper print has what? 200:1? This means that the saturation of the printed version would need to be over 3 times greater than the screen to overtake its gamut. I accept that the CMY inks may not be the exact complement of the RGB phosphor colours, but this is a problem of hue shift, not saturation. Then Andrew Rodney wrote: Then on page 113 of *Information Visualization* is a color gamut chart that shows the monitor gamut far exceeding the gamut of printed inks and the gamut of printed inks entirely within the gamut of the monitor I don't buy that! There are greens and cyan's in a CMYK SWOP like gaumt that fall outside monitor gamut. A monitor can't display a pure cyan. In the enclosed gamut map you cans see that the TR001 SWOP profile has areas that fall outside ColorMatch RGB... snip. A small shift in the green phosphor would eliminate the discrepancy, but the comparison between reflective and self-luminous colour spaces is problematic in any case. You only have to hold printed material side-by-side with a monitor for that to be self-evident. I'd be much more concerned about the SWOP inks not being able to reproduce a decent blue than any slight discrepency between Cyan renderings. As corroborative evidence, I found very little problem in getting a good visual match for the Epson 1270 inks on photo glossy paper into an sRGB colour space. The red actually gave the most trouble. I've pasted those colour patches back into the SWOP v ColourMatch chart. (see attached) The Epson 1270 is reckoned by many people to give one of the best outputs you can obtain with inks, so I would have thought that matching it's gamut would be a good test of any RGB space. The difficulty with placing ink colours on a conventional u/v diagram is that they aren't 'pure' colours, and so don't have a true locus in the colour space shown. IMHO the SWOP colour diagram is a 'cheat'. It seems to me as if the publishers of that chart have some vested interest in making RGB spaces look bad. Are they half-tone ink manufacturers by any chance? Afraid that web publishing might damage their business? Regards,Pete.
Re: filmscanners: Fw: Color Profiles for Printers was scanners
on 1/14/01 1:44 PM, photoscientia at [EMAIL PROTECTED] wrote: Whoa! Back up a minute. How is the scanner hardware supposed to know that it's scanning into a wide gamut space? As discussed in the other concurrent thread, all that the scanner can do is translate Red, Green, and Blue densities into digitised numbers. The makers don't even tell us what the spectral peaks of the scanner's RGB channels are. That's exactly why you need a scanner profile. You can't convert scanner RGB into anything without one. You can Assign a profile but that isn't necessarily going to do anything (it could actually make matters worse if you Assign a profile to a file that isn't in that condition). Andrew Rodney
RE: filmscanners: Re: So it's the bits?
Of course it does, but the voltage to toggle the LSB of the A/D, *relative to the maximum voltage from the CCD* When talking about number of volts/bit (technically, volts/code) the measurement is *USUALLY* done relative to the A/D input voltage range...but if you want to reference to the CCD output voltage range, well, OK...as long as that is stated. A/D converters vary more, of course, but I don't see what the input voltage has to do with the usability of a 14 bit output. Everything. If the input voltage to the converter isn't matched to the converter, you will not get the full dynamic range of the converter. Anyway, adding a bit of gain is hardly the basis for an entire design philosophy. "Output of CCD = 2.8 volts, input of A/D converter = 4 volts. Ugh! Add gain of 1.4." That's a no-brainer. Well, it's possibly a little more than that. If the CCD output is 0-2.8V, and the A/D input is -3V to +3V (typically, A/Ds take +- voltage swing), you need to level shift it (negative offset of 1.4V), then apply gain...I don't know the chips you are referring to, but perhaps they handle it effortlessly... Obviously, you have to also consider how much distortion these circuits introduce into the system, they may or may not be very good... It all really depends on how good a system you want to design. And doesn't explain why all the scanner manufacturers are now moving to 14 bits. Possibly because of cost. The lower bit converters aren't available any more, and 14 bits are cheap... Sometimes this happens, where higher spec parts are cheaper than older technology lower spec parts.
Re: filmscanners: Fw: Color Profiles for Printers was scanners
on 1/14/01 1:46 PM, photoscientia at [EMAIL PROTECTED] wrote: I've measured my monitor as having a 600:1 brightness range, a good paper print has what? 200:1? What's that got to do with color gamut? A small shift in the green phosphor would eliminate the discrepancy, but the comparison between reflective and self-luminous colour spaces is problematic in any case. You can't simply shift the green phosphor if they can't go any farther. It's not like the movie "Spinal Tap" where you can crank up the amplifier to 11. Today's displays don't have the gamut to do what we want (produce a pure cyan on screen). The Epson 1270 is reckoned by many people to give one of the best outputs you can obtain with inks, so I would have thought that matching it's gamut would be a good test of any RGB space. Here's the gamut of a 1270 using Photo paper next to sRGB. As I've mentioned in the past, output devices have gamut's who's shapes are quite different from RGB Working Spaces as you can see here. As you can see, the cyans and greens fall far outside sRGB. sRGB is a bit wider in reds. The Epson is short, as you'd expect in blues. IMHO the SWOP colour diagram is a 'cheat'. It seems to me as if the publishers of that chart have some vested interest in making RGB spaces look bad. Are they half-tone ink manufacturers by any chance? The gamut maps are generated from the profiles for both devices. The SWOP profile was created by Heidelberg from measured data of ink sheets from a press that confirms to TR001 SWOP spec. I have plenty of profiles I've made myself from CMYK proofing devices (Matchprint, Iris, Kodak Approval) which I'd be happy to map. But TR001 is a specific press standard that actually defines SWOP (anything not conforming to TR001 isn't officially SWOP even though you or a printer can call it SWOP). Andrew Rodney Epson vs. sRGB
Re: filmscanners: orange mask
I clicked on the URL in your message and it opened OK. Having tried it, I really don't recommend the procedure in the site though. - Original Message - From: Roman Kielich [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Sunday, January 14, 2001 2:52 AM Subject: Re: filmscanners: orange mask At 11:52 12/01/2001 -0800, you wrote: http://www.zocalo.net/~mgr/DigitalPhoto/derCurveMeister/index.htm 404 - not found "Don't worry about the world coming to an end today. It's already tomorrow in Australia".
RE: filmscanners: Re: So it's the bits?
I don't think anyone commented on my suggestion that a 14 bit A/D still gives more detail in the middle part of the range of values (where colour neg film generally is) precisely because the noise is lowest there? I understand what you are saying, but I don't believe that's what is done, or that it really helps in the way I believe you mean. The A/D will convert the same delta V over the entire capture range. Typically, the image data only falls in part of the range of the CCD, and should be more in the middle, not the ends. Typically, setpoints are applied to the high bit data, and the usable image data is taken only from that range. Typically, also, that usable image data is then mapped into 8 bit data. It is better to apply tonal curves to the high bit data, so you avoid replication of codes, which will manifest themselves as the 'comb effect' seen in the histogram...
RE: filmscanners: Re: So it's the bits?
At 04:44 15/01/01, : [EMAIL PROTECTED] wrote: .Which might explain why they use the term Density Range and not Dynamic Range - Dynamic Range certainly means the range that can be covered without changing the setup i.e. the range available at one instant. Hm. Well spotted! Tony Sleep But they *do* use Dynamic Range in some of their literature (4.2 in Nikon's product data sheet for the 4000 ED and their model comparison sheet, provided by Nikon at this past week's Mac World). Yes I noticed this about 5 stupid minutes after I wrote the first comment! The truth as usual might be more stupidity than conspiracy. Probably there is some serious thinking about spec presentation by technical people arguing with sales people as to what they can get away with, resulting in a finely balanced agreement as to how to phrase this specification. Then somewhere downstream other sales people mess it all up by not appreciating the niceties of what was agreed elsewhere and plonk in the new figure with what they think is a "synonymous" name. Cheers Julian Julian Robinson in usually sunny, smog free Canberra, Australia
Re: So it's the bits? (Was: filmscanners: Sprintscan 120
At 07:45 15/01/01, Pete wrote: All the available CCDs on the market today are limited to a dynamic range of 5000:1 (~12 bits) at normal temperatures. Aha! That is the figure I was wondering about. Thanks so much for this useful and factual piece of info. Given the physics I would guess that noise figures are already towards thermal limits (?)and if so it is not possible to do much better without cooling. So I guess too that drum scanners etc must use photomultipliers or something other than CCDs. But we don't know whether the new Nikons do or don't use split exposures - which seems to be the logical way to go for CCD scanners - and should be easy for Nikon to implement given LED sources. Maybe they do? And probably they don't looking at the fast scan times. Multiple exposures would significantly add to the scan time. I wonder if they have considered this as a slower option. And then I wonder why, when they already do multi-passes to reduce noise as in the LS2000, why they don't up the exposure for subsequent scans? Maybe it is hard to keep things linear? Just thinking aloud, Julian Julian Robinson in usually sunny, smog free Canberra, Australia
RE: filmscanners: Re: So it's the bits?
Austin wrote: I don't think anyone commented on my suggestion that a 14 bit A/D still gives more detail in the middle part of the range of values (where colour neg film generally is) precisely because the noise is lowest there? I understand what you are saying, but I don't believe that's what is done, or that it really helps in the way I believe you mean. The A/D will convert the same delta V over the entire capture range. I understand that the delta V is the same. The point is that the comparison between the signal voltage and delta V is much more favourable in the middle to upper areas of the capture range. Typically, the image data only falls in part of the range of the CCD, and should be more in the middle, not the ends. Well, that's part of my point. Assuming CCD output voltage rises with light intensity, a really dark section of a slide will produce the lowest voltage, which may get lost in the thermal noise of the CCD. The signal to noise ratio should improve as the voltage increases, so that the middle to higher light intensities should produce much more accurate samples than really dark areas. In the case of a neg, the darkest areas (actually the brightest areas of the original scene) are still nowhere as dark as a slide. So the majority of the actual image information of a neg, or the midtones of a slide should be in the best part of the CCD response and have a really good signal to noise ratio - so 14 bit accuracy is actually *useful* for these areas but less so for the more dense areas of the film. In the case of a neg where you want to expand the subtle range of tonal shifts in the neg, surely the more bits the merrier? Rob Rob Geraghty [EMAIL PROTECTED] http://wordweb.com
RE: filmscanners: Re: So it's the bits?
Typically, the image data only falls in part of the range of the CCD, and should be more in the middle, not the ends. Well, that's part of my point. You're suggesting treating the CCD non-linearly it appears. There is a thought to that, but I will say, that you're probably not going to get any better (read as more usable) information from it...would be my first thought. I believe that doing either multiple exposures and/or multiple input ranges pretty much does the same thing, doesn't it?
