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false_Aesthetic
30-Sep-2006, 06:57
Hey,

There's a debate going on at school about how to scan.

A few of us think that you should get as close as possible to the final image while scanning and then use photoshop to do minimal corrections.

Others say that you should just scan with as much data as possible and do all your corrections in photoshop.

Both groups agree that it should be done at 16 bit.

Does anyone have an opinion on this? (I'm sure ya'll do)

Thanks

T

David A. Goldfarb
30-Sep-2006, 07:21
Either way it's post-processing for the most part. Use the tool that works better.

Here's another suggestion--get as close to the final image as possible in the camera so you can get the most out of the post-processing options that are available.

Brian Ellis
30-Sep-2006, 07:34
Back when Photoshop was limited as to what editing could be done in 16 bit I used to do as much as possible in the scan. But now that Photoshop can do most things in 16 bit I do most editing in Photoshop and try mainly to just get as much information as possible in the scan. I agree with David that ideally you get the image as close to final as possible in the camera and minimize the editing regardless of where it's done. But of course inherent limitations in the media and equipment can sometimes make that difficult to do.

Gordon Moat
30-Sep-2006, 10:45
Partially it could depend upon which scanner you are using. When you have a high end scanner, like a Creo or Screen, or a drum scanner, the tendency is to adjust everything in the scanner software; sometimes there is no need to even go into PhotoShop. On low to mid range scanners (Epson, MicroTek, Canon, et al) you could do many things in software, though there is often a desire to do better than what the scanner can output; some might consider that a need for manipulation in PhotoShop.

You should approach scanning as an output and results procedure. When you know the final parameters needed, and you scan directly to that, your workflow is more streamlined. This becomes important as a professional, in that billing your time is an issue; amateurs might enjoy spending more time in PhotoShop and might be less concerned about time spent at a computer. However, this is also somewhat software dependent, in that some scanning software either does not give a very good preview, or simply lacks a good range of adjustments.

If you plan on manipulating an image, it can be better to do so using 16 bit images. Unfortunately some scanning software leaves many adjustments in 8 bit only. The majority of commercial printing uses 8 bit image files. If you can adjust everything to suit in 8 bit, are outputting for CMYK, and not limited by the scanner or scanner software, then there is nothing wrong with an 8 bit scan.

So the simple answer to your question is it depends upon your scanner and software. There is rarely a situation when one procedure should be blindly followed or in which only one approach should always be used. The other answer to this is to try it out, compare variations to see the affects upon output results, then find the workflow that is best for what you want to achieve with the gear you use.

Ciao!

Gordon Moat
A G Studio (http://www.allgstudio.com)

false_Aesthetic
30-Sep-2006, 11:45
Hey,

We're using an Imacon 848 and a 646. Most of us are outputing on an Epson 9800.


Those of us that shoot 8x10 are limited to a Microtek or Epson 1680.

Thanks again for the input.


T.

Bruce Watson
30-Sep-2006, 12:58
So the simple answer to your question is it depends upon your scanner and software. There is rarely a situation when one procedure should be blindly followed or in which only one approach should always be used. The other answer to this is to try it out, compare variations to see the affects upon output results, then find the workflow that is best for what you want to achieve with the gear you use.

What Gordon said!

robc
30-Sep-2006, 13:52
it's a myth that all things can be fixed in photoshop. Many photoshop actions are destructive and so the old computer adage from well before the days of pc's still holds true. i.e. GIGO which stands for Garbage In Garbage Out. Or to put it simply, at every stage of the process you should try to maximise quality. Stick to that and you won't go far wrong. At any stage that you don't bother with that principle, then you are just passing poor quality data to the next stage in the process.

Saulius
30-Sep-2006, 21:29
My understanding is that when you work images in Photoshop you are losing something because it's a destructive process. Someone corretct me if I'm wrong. So I've always thought it best to do most of your image corrctions during the scanning process. Your scanner will have more data to work with than Photoshop will so when you make corrections during the scanning phase you will have a higher quality image. Now to what degree it is higher quality I can't exactly say but this is what I've read and heard about before. As others have said it also depends on your software, and definately scan in 16 bit mode if possible. Once you have the image in Photoshop you will still have manipulations to do but they will be less drastic so that should help with the image quality. And as David says
get as close to the final image as possible in the camera so you can get the most out of the post-processing options that are available

Marko
30-Sep-2006, 22:16
My understanding is that when you work images in Photoshop you are losing something because it's a destructive process. Someone corretct me if I'm wrong. So I've always thought it best to do most of your image corrctions during the scanning process. Your scanner will have more data to work with than Photoshop will so when you make corrections during the scanning phase you will have a higher quality image. Now to what degree it is higher quality I can't exactly say but this is what I've read and heard about before. As others have said it also depends on your software, and definately scan in 16 bit mode if possible. Once you have the image in Photoshop you will still have manipulations to do but they will be less drastic so that should help with the image quality. And as David says

You loose in processing, not in Photoshop per se. With scanning, like with any other kind of digital capture, you have to have some processing in order to be able to see the image as we are used to. And that's even before any corrections are applied. The question, therefore, is not if but where do you do it.

So the real question is where do you loose less data and where do you achieve better quality output and, last but not least, which process is most efficient.

Processors in digital capture devices are highly specialized but have nowhere near the power and capacity of even the wimpiest PC. It sounds logical that only the most specialized processing, such as demosaicing should be done on the spot and everything in Photoshop or whatever other program one might be using. That, among other things, is the real advantage of RAW format, either in scanners or digital cameras.

buze
1-Oct-2006, 05:11
I have more trust in Adobe's Engineers ability to write image processing than, say, Epsons. Therefore I do try to scan to get as much of the Dmax of the image as I can (just set the white and black point), get it into a file, then process it in photoshop.

Using correction "layers" you do not touch the image until the time you are really happy with the rendition; you then just have to "commit" the changes by flattening the layers in 16 bits (even if photoshop is actualy 15 bits only) and export to your favourite format.

robc
1-Oct-2006, 07:53
life was so simple before the advent of digital imaging. You never had to worry about any of this ****. You just put your neg into the enlarger and printed it.

Marko
1-Oct-2006, 08:46
life was so simple before the advent of digital imaging. You never had to worry about any of this ****. You just put your neg into the enlarger and printed it.

If you think that's complicated, just think how many fewer ailments there were before the advent of medical imaging!

:D

Sanders McNew
1-Oct-2006, 13:30
FWIW, I've found that if I can get the image close enough to final in the initial scan, I can work easily in 8-bit without compromising image quality. If you're scanning LF negatives you are already putting a tremendous drain on memory and processing power by scanning at the scanner's native resolution. Doing it in 16-bit is overload for my computer. I'd rather scan at a higher resolution in 8-bit than a lower one in 16-bit, so I adjust in the scanner software for greater efficiency in PS.

Sal Santamaura
1-Oct-2006, 16:40
life was so simple before the advent of digital imaging...You just put your neg into the enlarger and printed it.I still do. Frequently don't even use an enlarger.

tim atherton
1-Oct-2006, 16:51
Originally Posted by robc
life was so simple before the advent of digital imaging...You just put your neg into the enlarger and printed it.

I still do. Frequently don't even use an enlarger.

How often do you manage to get a straight off print from your negs - sans dodging/burning, spotting (on exactly the right grade paper first time) etc

If all you ever do is plop the neg in the enlarger/contact frame and print et voila, you are a lucky man

Sal Santamaura
1-Oct-2006, 17:10
How often do you manage to get a straight off print from your negs - sans dodging/burning, spotting (on exactly the right grade paper first time) etc

If all you ever do is plop the neg in the enlarger/contact frame and print et voila, you are a lucky manNeither robc nor I wrote anything about the need or lack of need for dodging/burning, etc. in our posts. Why would you ask that question?

The answer is rarely, except for spotting, which is almost never required. Anal retentive attention to cleanliness has so far kept me from spending much time spotting. That will change when I move to a more arid climate.

The notion that scanning (or digital capture) + PS is "better" than optical printing seems to be widespread. It may make economic sense for a professional, but I disagree that the results are superior. Also, as an engineer whose work life revolves around electronics and computers, I've absolutely no interest in spending discressionary time making images using those tools.

tim atherton
1-Oct-2006, 17:51
Neither robc nor I wrote anything about the need or lack of need for dodging/burning, etc. in our posts. Why would you ask that question?


"Life was simple before the advent of digital imaging...You just put your neg into the enlarger and printed it."

Why? Because frequently, making a good print from a neg isn't "simple".

The notion that scanning (or digital capture) + PS is "better" than optical printing seems to be widespread. It may make economic sense for a professional, but I disagree that the results are superior.

Now, who said that in this thread and why would you make that statement?

Also, as an engineer whose work life revolves around electronics and computers, I've absolutely no interest in spending discressionary time making images using those tools.

As someone who has spent thousands of hours in the darkroom printing archived negatives, making copy negatives etc I have plenty of interest in other, different ways of making images as well

Don Bryant
1-Oct-2006, 18:30
(even if photoshop is actualy 15 bits only)

Okay I'll bite. Why is PS only 15 bits?

BTW, I agree with your post completely. I scan for the most information and then do adjustments in PS. I don't understand why folks make scanning more complicated than it needs to be.

Don Bryant

Kirk Gittings
1-Oct-2006, 19:36
It is best to make major ballpark adjustments (like steep curves, global color etc.) in your scanning software where there is the most information to work with. Silverfast and other software companies advocates this and by my testing it is absolutely true.

Tim Lookingbill
1-Oct-2006, 23:44
I agree with Kirk.

I've tried many techniques scanning negatives including applying NegPos within Epson Scan on my refurb 4870 taking advantage of its CM implementation writing to ProPhotoRGB in 16bit. But scanning using the traditional film negative setting and applying severe tonal corrections to get the look I want produces beefier previews and cleaner histograms with less noise viewed at 100% in PS. It's just the scanner software previews can't show this, but it does provide an adequate starting point to edit in PS.

Scanning negatives any other way produces clipping, more noise and spikey histograms, though the preview is a bit more vibrant and similar to scanning using the traditional neg film setting. Zooming in within PS will tell you which technique is best.

Your PS histogram will also tell you how much quality data is captured with whatever technique used.

Marko
1-Oct-2006, 23:50
Neither robc nor I wrote anything about the need or lack of need for dodging/burning, etc. in our posts. Why would you ask that question?

The answer is rarely, except for spotting, which is almost never required. Anal retentive attention to cleanliness has so far kept me from spending much time spotting. That will change when I move to a more arid climate.

The notion that scanning (or digital capture) + PS is "better" than optical printing seems to be widespread. It may make economic sense for a professional, but I disagree that the results are superior. Also, as an engineer whose work life revolves around electronics and computers, I've absolutely no interest in spending discressionary time making images using those tools.


If this were yet another one of those digital vs. analog threads, the counter-argument would go something like "you just plop your negative into the scaner, press the button and presto! out comes the image.

But it is not.

This thread is all about "those other tools" - the opening question was whether it was better to make adjustments and corrections in scanning software at scanning time, or later during post-processing in Photoshop or such.

You can take it as a digital counterpart to one of those endless Pyro wars, if you will, only more civil and less flamable... ;)

false_Aesthetic
2-Oct-2006, 04:43
Your PS histogram will also tell you how much quality data is captured with whatever technique used.

Yeah, I thought about this, but when I work on my images either way and move from 16 bit to 8 bit, I get "good" looking histogram. That is to say, the histogram isn't riddled with gaps.

Maybe I'm not understanding what you're saying though.

----

I really appreciate all your input on this subject. But lets try to keep the discussion away from analog vs digital, etc. I'm pretty sure both are just means to an end.

----


Again, thanks

T

robc
2-Oct-2006, 04:45
If this were yet another one of those digital vs. analog threads, the counter-argument would go something like "you just plop your negative into the scaner, press the button and presto! out comes the image.

But it is not.

This thread is all about "those other tools" - the opening question was whether it was better to make adjustments and corrections in scanning software at scanning time, or later during post-processing in Photoshop or such.

You can take it as a digital counterpart to one of those endless Pyro wars, if you will, only more civil and less flamable... ;)

Your ususal low level garbage. Firstly "you just plop your negative into the scaner, press the button and presto! out comes the image" isn't true because a scanner doesn't produce prints. How remiss of you to forget that. i.e. scanning is one of the additional processes which are not required in traditional printing. Secondly, the Pyro arguments are still going on because for here at least, film development comes before the digital process. i.e neither of your arguments are pertinent to the argument as ususal.

Then we have all the other additional time consuming processes such as scanner calibration, monitor calibration, reading a thousand conflicting reviews about which scanner, monitor, monitor calibrator, PS technique, print driver, rip software, paper profiles, etc etc etc is better. All in the knowledge that actually our scanner is a piece of **** compared to the scanner we would really like to own.

Then we convince ourselves that our digital output will last a lifetime because Mr Wilhelm says so. Then go back and replace all your digital kit because Mr Epson just discovered that his new print head, ink and paper substrate is "So much better" than the one you bought last week, that you would be cheating your clients if you didn't use them.

Then we have traditional: make sure the enlarger is squared/perpendicular to base board. Print on our chosen paper. Jobs a good'un. Done in a fraction of the the time, effort and cost. And we don't need a ****** computer with wa hole range of poorly developed software packages to do it.

Get the picture.

Ted Harris
2-Oct-2006, 05:45
Quick note to take us back to the original question and avoid any comparisons which were not the point .... Gordon and Kirk are right.

First, doesn't matter what sort of equipment you are talking about - simple or complex - (lens, camera, enlargr, film processing machine, print processing rollers, computer, scanner, auto, toaster, etc.) it will work much better if you spend some time making sure it is properly functioning and that means correctly set, calibrated or whatever is needed.

Second, the most important thing you can do while scanning is insure that you capture all the information in the image that you will want to work with as you movet toward a final print. Best example, if you set either your white or black point incorrectly you may not capture information you want. If it isn't there, there is no way you can manipulate it in a photo editing program.

Third, beyond information capture (above) there is very little that you can't do after the scan but there are some things that take an inordinately long time if you have to do them after the scan, correcting a color cast for example.

All threee of these apply, as noted above, to the consumer scanners and in this instance I would include the Imacons, their software is just not as sophisticated as that of the high end machines.

Marko
2-Oct-2006, 05:50
Your ususal low level garbage.

Well, it seems no matter how low I go, you still fail to understand the point and keep being your usual vulgar self.


Get the picture.

Indeed.

Which is to say that this thread is about scanning workflow, not the usual digital vs. analog noise.

If only you bothered yourself enough to actually read the opening question of the thread, you just might have realized that this thread has nothing to do with anything you wrote about. Then you might have even understood my sarcasm.

Tim Lookingbill
2-Oct-2006, 06:56
"Yeah, I thought about this, but when I work on my images either way and move from 16 bit to 8 bit, I get "good" looking histogram. That is to say, the histogram isn't riddled with gaps.

Maybe I'm not understanding what you're saying though."


False_Aesthetic,

I was referring to scanning negatives as positives using Epson's CM feature to get the orange mask accurate looking and with matched previews editing in PS. In addition I get Epson Scan to write the data to a wide working space like ProPhotoRGB in 16bit. Unfortunately the histograms it produces when first opened in PS are full of spikes in all channels compared to just using Epson Scan's Neg film setting working with a positive preview using Epson's edit tools.

I started taking the NegPos technique even further by inverting and manipulating the resultant positive image in Epson Scan until I got just as good a preview as if using regular negative film setting. The NegPos positive preview still produced spikey histograms in PS before any editing was applied and for some reason bright greens on backlit tree foliage clipped the blue channel converting to sRGB capturing either in ProPhotoRGB or AdobeRGB within Epson Scan.

Check out the attachment to see what I mean. The regular sRGB capture on the left is most accurate to what I saw through the lens.

Sal Santamaura
2-Oct-2006, 07:38
"The notion that scanning (or digital capture) + PS is "better" than optical printing seems to be widespread. It may make economic sense for a professional, but I disagree that the results are superior."

Now, who said that in this thread and why would you make that statement?No one "said" it in this thread. Why would you ask that question? I haven't found any forum rule requiring that posts directly respond only to things explicitly stated in prior posts. Peripheral observational statements are fair game in the course of bulletin board conversations here. You took advantage of that capability yourself when replying to my first post in this thread.


"Also, as an engineer whose work life revolves around electronics and computers, I've absolutely no interest in spending discressionary time making images using those tools."

As someone who has spent thousands of hours in the darkroom printing archived negatives, making copy negatives etc I have plenty of interest in other, different ways of making images as wellWhich is why this thread exists. Neither I nor anyone else wrote that you shouldn't have interest in those other ways of making images or be able to discuss them here.


If this were yet another one of those digital vs. analog threads, the counter-argument would go something like "you just plop your negative into the scaner, press the button and presto! out comes the image...You can take it as a digital counterpart to one of those endless Pyro wars, if you will, only more civil and less flamable... ;)Marko, I did not write anything concerning the difficulty of creating a "good" digital print vs. a "good" wet darkroom print. My first post merely expressed a preference for the simple tools used in a wet darkroom.

I strive for civility in all interpersonal relationships. If we can't calmly discuss something as ultimately unimportant as scanners, PS and wire clothes hangers with cardboard bits taped to their ends, what hope is there for the world?

Marko
2-Oct-2006, 11:31
Marko, I did not write anything concerning the difficulty of creating a "good" digital print vs. a "good" wet darkroom print. My first post merely expressed a preference for the simple tools used in a wet darkroom.

I strive for civility in all interpersonal relationships. If we can't calmly discuss something as ultimately unimportant as scanners, PS and wire clothes hangers with cardboard bits taped to their ends, what hope is there for the world?

Sal,

I did not imply that you were uncivil or anything close to it, that was just a little humorous jab at the way certain kinds of discussions degenerate into flame wars and profanities, as was quickly demonstrated here as well (and not by you).

buze
5-Oct-2006, 00:55
Okay I'll bite. Why is PS only 15 bits?

BTW, I agree with your post completely. I scan for the most information and then do adjustments in PS. I don't understand why folks make scanning more complicated than it needs to be.

Don Bryant

Hi Don. Photoshop doesn't encode values from 0 to 65535, it just uses 0 to 32767. I don't know why, it's just disclosed in Adobe's plugin development kit...