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Update to Epson scanning article: how to bypass all tonal adjustments
You might find this update helpful: How to Bypass All Tonal Adjustments.
It shows how to get an image directly from an Epson scanner with no tonal adjustments, using the MacOS and Windows generic drivers as well as Epson Scan software.
If anyone knows how to do this with VueScan (or would like to share any other helpful suggestions or corrections), please let me know so that the article will be more complete and informative.
Thanks !
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1 Attachment(s)
Re: Update to Epson scanning article: how to bypass all tonal adjustments
Ken,
Is that scanning as a negative?, my version of Epson scan, doesn't actually work like that for negative. My version is the latest that for the 4990, so a bit old...
You can do the same in vuescan just by choosing the following:
Attachment 173373
Keep in mind this will have sRGB gamma applied, so not strictly correct that no changes have been applied.
or you can just choose raw in viewscan which will give you a gamma of 1.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ted Baker
Ken,
Is that scanning a negative?, my version of Epson scan, doesn't actually work like that for negative. My version is the latest that for the 4990, so a bit old...
You can do the same in vuescan just by choosing the following:
Attachment 173373
Keep in mind this will have sRGB gamma applied.
or you can just choose raw in viewscan which will give you a gamma of 1.
In the article, in the section where I deal with VueScan settings, I show that the default settings result in some clipping: I recommend other settings to circumvent the problem.
I am using an Epson V700 and it's been a while since I've updated my copy of VueScan.
Some people prefer to get nothing more than a "raw" scan from the scanner and perform all adjustments in Photoshop, Lightroom, etc. To date, no one has ever shared with me a method to get that unaltered scan using VueScan. I added this new section to the article after a reader contacted me with information about the MacOS Image Capture application. I did a little digging and found the corresponding Windows feature.
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2 Attachment(s)
Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ken Lee
In the article, in the
section where I deal with VueScan settings, I show that the default settings result in some clipping: I recommend other settings to circumvent the problem.
I am pretty sure none of those setting in the current version would do what you want.
The setting I gave should result in no additional changes, other than sRGB gamma being applied, but I don't bother in any case and just scan it as raw file.
When you have it right the graph should look like this:
Attachment 173374
To get a raw scan in vuescan just click, the raw scan option:
Attachment 173379
This will NOT have any gamma corrections applied. Vuescan also gives the option to adjust the CCD exposure time manually.
Anyway I hope that helps :)
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
The VueScan raw file is an output file type, like JPG, PNG, etc. It is a TIFF embedded in a file, with some additional header information, if I understand correctly. In that sense it is like the raw files we get from digital cameras: no compression.
Vuescan automatically adjusts image brightness as we crop. We can't bypass that. Note that the settings on the left-hand side remain unchanged as we crop.
http://www.kennethleegallery.com/ima...m/VueScan1.png
Here our crop includes a lot of white background: VueScan has darkened the scan to accommodate the high average tone.
http://www.kennethleegallery.com/ima...m/VueScan2.png
Here our crop includes mostly middle grays: VueScan has lightened the scan accordingly.
With the Epson drivers, cropping the image also creates tonal adjustments... but we can dispose of them if we like. We can't do that with VueScan.
http://www.kennethleegallery.com/ima...rum/Epson1.png
http://www.kennethleegallery.com/ima...rum/Epson2.png
With the generic drivers provided by Microsoft and Apple, no matter how we crop the image, the resulting scan is the same. Adjustments are not applied.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ken Lee
The VueScan raw file is an output file type, like JPG, PNG, etc. It is a TIFF embedded in a file, with some additional header information, if I understand correctly. In that sense it is like the raw files we get from digital cameras: no compression.
You don't understand correctly. But I can't say I blame you... Vuescan is not the most accessible program in any case..
I hope you don't take that the wrong way. Your site is very inspirational!
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4 Attachment(s)
Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ken Lee
You might find this update helpful:
How to Bypass All Tonal Adjustments.
It shows how to get an image directly from an Epson scanner with no tonal adjustments, using the MacOS and Windows generic drivers as well as Epson Scan software.
If anyone knows how to do this with VueScan (or would like to share any other helpful suggestions or corrections), please let me know so that the article will be more complete and informative.
Thanks !
How does the Epson Scan deal with Gamma with these settings. Does it still encode in gamma 2.2 or is there a way to force it to give a true Linear scan with a Gamma of 1.0
To produce a Linear Scan with VueScan to be used with something like ColorPerfect (ColorNeg) we can use these settings
Attachment 173396 Attachment 173397 Attachment 173398 Attachment 173395
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ken Lee
I am using an Epson V700 and it's been a while since I've updated my copy of VueScan.
Some people prefer to get nothing more than a "raw" scan from the scanner and perform all adjustments in Photoshop, Lightroom, etc. To date, no one has ever shared with me a method to get that unaltered scan using VueScan.
Why not use EpsonScan rather than VueScan.
EpsonScan came with my V750. I'm sure it also came with your V700.
For a plain-vanilla scan, you don't need any of the fancy VueScan features, so why use it?
- Leigh
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Vuescan automatically adjusts image brightness as we crop. We can't bypass that. Note that the settings on the left-hand side remain unchanged as we crop.
Ken, In VueScan, doesn't Crop Buffer % value determine how VueScan adjusts the brightness
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ken Lee
The VueScan raw file is an output file type, like JPG, PNG, etc.
It is a TIFF embedded in a file, with some additional header information, if I understand correctly.
Sorry, Ken,
But that's not possible.
JPG et al are compression formats.
Even if you choose "lossless compression", you still get pixel mangling.
TIFF is a direct element-to-pixel dump of the sensor's raw data. If you do a TIFF from a scanner or sensor, the file size is the same as the sensor pixel count plus minor overhead.
- Leigh
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
IanBarber
Ken, In VueScan, doesn't Crop Buffer % value determine how VueScan adjusts the brightness
Even if you set it to 0, the brightness of the image changes as you vary the cropping.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Leigh
Why not use EpsonScan rather than VueScan.
EpsonScan came with my V750. I'm sure it also came with your V700.
For a plain-vanilla scan, you don't need any of the fancy VueScan features, so why use it?
- Leigh
Yes, that's one of the points made in the article: I don't use VueScan. It's a rather long article, so that may have escaped people's attention if they only had time to skim it, or skim this thread for that matter.
I have simply added some information to the article, for those people who have asked me how to make a plain scan with no adjustments whatsoever.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ken Lee
Even if you set it to 0, the brightness of the image changes as you vary the cropping.
I will do some testing with this tomorrow especially with the crop buffer and report back my findings
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
IanBarber
How does the Epson Scan deal with Gamma with these settings. Does it still encode in gamma 2.2 or is there a way to force it to give a true Linear scan with a Gamma of 1.0
When you scan in epson scan with the gamma set to 1.0, the file you output will be encoded into the sRGB gamma (most likely 100% correctly) unless you say differently I think you can also use adobeRGB which has similar gamma. You can convert it easily enough to 1.0, a couple of different ways, and you should get exactly the same thing, before epson scan applies the correction. ColorPerfect I understand offers this feature. You only need a gamma of 1.0 if you intend to do your own image processing, in which case you can convert it yourself as long as you know the original gamma. When you use tools like LR they will automatically convert it a gamma of 1.0 internally to store in its own working space.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ken Lee
Vuescan automatically adjusts image brightness as we crop.
What your probably seeing there is vuescan simulating the exposure change, that it intends to make when you actually do the scan. Vuescan actually allows you manual control this, and I think it also allows you do this for each color channel. It certainly allows the adjustment of the later. Just like changing the shutter speed, changing the exposure time of the CCD is not a tonal change.
There is no manual control of this in epson scan, though presumably it makes use of this feature, most probably it has calculated it before you are presented with the preview.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
When you scan in epson scan with the gamma set to 1.0, the file you output will be encoded into the sRGB gamma (most likely 100% correctly) unless you say differently I think you can also use adobeRGB which has similar gamma.
Ted, are you saying that even if you choose gamma 1.0 in Epson Scan, it will converting along the way to gamma 2.2 which is what (sRGB or AdobeRGB 1998) are
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
IanBarber
Ted, are you saying that even if you choose gamma 1.0 in Epson Scan, it will converting along the way to gamma 2.2 which is what (sRGB or AdobeRGB 1998) are
Yes, otherwise you would not be a happy photographer :) BTW sRGB is not exactly 2.2 but close enough, same for adobeRGB.
In addition I assume we are talking about scanning positives, because scanning a negative is different.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ted Baker
Yes, otherwise you would not be a happy photographer :) BTW sRGB is not exactly 2.2 but close enough, same for adobeRGB.
In addition I assume we are talking about scanning positives, because scanning a negative is different.
I was referring to scanning black and white negatives
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
IanBarber
I was referring to scanning black and white negatives
In that case the gamma etc, still applies. But the method of inversion is potentially unique to each program, it may not be a big secret, the point being no vendor that I am aware of publishes it. For example what is the method used by epson? How this is done most certainly effects the tonal relationship, this is most obvious in colour photography, but it also applies in BW.
If you do a raw scan (Vuescan/Silverfast/DSLR raw file), a negative will come out looking like a negative, with no gamma applied. If you use epson scan you can scan a negative as a positive, and remove the sRGB gamma later. I believe colorperfect supports the later.
If you stay in 16bit integer, you can potentially unravel any tonal changes, exactly if you know what the original changes were (assuming you round up/down correctly). Clipping is the exception of course, but that is not a tonal change. If you use a RGB curve tool in software later down the line you can also unravel those changes, (or indeed make your own), and get back to the original potentially. I hope this makes some sense.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ted Baker
What your probably seeing there is vuescan simulating the exposure change, that it intends to make when you actually do the scan. Vuescan actually allows you manual control this, and I think it also allows you do this for each color channel. It certainly allows the adjustment of the later. Just like changing the shutter speed, changing the exposure time of the CCD is not a tonal change.
There is no manual control of this in Epson scan, though presumably it makes use of this feature, most probably it has calculated it before you are presented with the preview.
I think I finally grasp what you are saying. Duhhh :rolleyes:
I made a scan with VueScan and configured it to output both a raw file and a tiff file. The tonal scale of the tiff file was affected by cropping and adjustments made in the Color tab like curve low, curve high. In addition, a gamma adjustment of approximately 2.2 has been applied to the tiff file. The resulting tiff file matches what we see in the preview pane.
The raw file, on the other hand, looks rather dark, because not even a gamma correction has been applied. It's just the original scanner acquisition of the image.
http://www.kennethleegallery.com/ima...iffandraw1.png
If we apply a gamma correction to the raw file, it begins to resemble the TIFF image (which may also contain tweaks from the Color tab and cropping).
http://www.kennethleegallery.com/ima...iffandraw2.png
Finally, the Epson scan, Apple Image Capture and Windows Scan drivers are all silently applying a gamma correction to the scan. Turning off all corrections in the Epson drivers, we get an image which matches Apple Image Capture and Windows Scan, but none of these 3 approaches actually delivers the original scanner capture because a gamma adjustment has been applied in all 3 cases. In fact, the only configuration which delivers the original scanner capture, is the VueScan raw file.
...Is this correct ?
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Ken, after you scanned the image as a RAW file in VueScan and brought it into Photoshop, what option did you choose on the profile Mismatch dialog box ?
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
IanBarber
Ken, after you scanned the image as a RAW file in VueScan and brought it into Photoshop, what option did you choose on the profile Mismatch dialog box ?
I don't get a profile mismatch prompt because I have them all turned off.
I'm no expert but my workflow is rather simple, 99% monochrome except for snapshots.
For printing I work in Gray Gamma 2.2 because that's what Piezography uses with Quadtone RIP. For making JPG files for the web I use sRGB.
http://www.kennethleegallery.com/ima...orSettings.png
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
My guess is that when you bring the RAW scan into Photoshop, it will be an untagged negative. To get it to a positive, are you just inverting the image and then applying the Gamma 2.2
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
IanBarber
My guess is that when you bring the RAW scan into Photoshop, it will be an untagged negative. To get it to a positive, are you just inverting the image and then applying the Gamma 2.2
In these tests I have made low-res scans of a positive (a recent print) because it's easy to spot a faithful rendition when we can see the original. It's easy to tell that the 3 scans made with no adjustments (Epson with adjustments disabled, Apple Image Capture and Windows Scan) all resemble the original print and closely match one another. Similarly, it's easy to see that the VueScan raw file is dramatically different, as no Gamma adjustment has been applied.
Normally after scanning a b&w negative I explicitly convert it to Gray Gamma 2.2 and save it in Photoshop PSD format. (When acquiring a raw file from my digital camera, I do the same thing.) I perform all corrections and printing in Gray Gamma 2.2.
If I make a JPG to put on a web page, I convert to sRGB.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Ken, this is tremendous, thanks for updating your tutorial and sharing it. For black and white, I had migrated to the 0-255 slider settings, influenced by my C-41 work.
For gamma, with C-41, do you have suggestions? With color negative, correcting for the orange mask means either adding or subtracting data (or multiplying or dividing, depending on your workflow). In this situation, clipping, particularly of highlights, needs to be avoided. It is challenging.
Have you done tests with Epson Scan gamma set at values other than 1.0 or 2.2?
I have scanned color negatives at gamma 3.0 and 4.0, all other settings per your tutorial, save as .tiff. Higher gamma in Epson Scan shifts the negative histogram to the right. For box-speed-exposed Portra 400, the histogram falls almost in the middle, which is helpful for subsequent color correction work. I find that box speed exposure of Portra 400 with gamma 1.0 or 2.2 easily results in clipped highlights after color correction (orange mask and color balance).
Does Epson Scan gamma setting change data acquisition from the sensor, or is it a software manipulation?
Thanks again, this is valuable and helpful.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ken Lee
I think I finally grasp what you are saying. Duhhh :rolleyes:
...
Finally, the Epson scan, Apple Image Capture and Windows Scan drivers are all silently applying a gamma correction to the scan. Turning off all corrections in the Epson drivers, we get an image which matches Apple Image Capture and Windows Scan, but none of these 3 approaches actually delivers the original scanner capture because a gamma adjustment has been applied in all 3 cases. In fact, the only configuration which delivers the original scanner capture, is the VueScan raw file.
...Is this correct ?
Yes of those options the Vuescan raw, is the only one unchanged in anyway. (There are a few ways to save raw in vuescan, that will allow minor corrections BTW).
I don't know anything about Apple Image Capture and Windows Scan, as they are 8 Bit?, I won't comment on them as they are probably a distraction.
Back to epsonscan, it is my understanding that if you scan a positive per you instructions, it will be same as the viewscan raw with the following adjustments:
1. the sRGB gamma applied
2. the colors are adjusted to match the sRGB color coordinates.
The later is point is very minor, I asked Ed Hamrick (vuescan author) about it, but he is not keen on divulging those kind of details. To be fair I can't imagine epson would help either...
But it is important to note, that if you are dealing with a negative, all the scanning programs will apply their respective algorithms to invert the negative.
Most people want an image in sRGB, or something very similar in anycase, so it's important to understand the context.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
chassis
Ken, this is tremendous, thanks for updating your tutorial and sharing it. For black and white, I had migrated to the 0-255 slider settings, influenced by my C-41 work.
For gamma, with C-41, do you have suggestions? With color negative, correcting for the orange mask means either adding or subtracting data (or multiplying or dividing, depending on your workflow). In this situation, clipping, particularly of highlights, needs to be avoided. It is challenging.
Have you done tests with Epson Scan gamma set at values other than 1.0 or 2.2?
I have scanned color negatives at gamma 3.0 and 4.0, all other settings per your tutorial, save as .tiff. Higher gamma in Epson Scan shifts the negative histogram to the right. For box-speed-exposed Portra 400, the histogram falls almost in the middle, which is helpful for subsequent color correction work. I find that box speed exposure of Portra 400 with gamma 1.0 or 2.2 easily results in clipped highlights after color correction (orange mask and color balance).
Does Epson Scan gamma setting change data acquisition from the sensor, or is it a software manipulation?
Thanks again, this is valuable and helpful.
You're welcome and I very much appreciate the helpful information shared by others here and elsewhere. Ted has provided several valuable missing links.
I've done very little scanning of color materials: hopefully there are tutorials on the web which cover the issues. Positives are hard enough, but negatives are more challenging because we never know what they "really" look like unless we scan a calibration target (hint hint).
Being merely a consumer of these consumer-grade Epson scanners, it's not clear to me whether any adjustments we make via scanner drivers affect the process before image acquisition (aperture, exposure time, lamp brightness in physical terms or gain or other attributes in electronic terms) or whether all the adjustments we request are performed in software, after image acquisition. To be certain, you'd have to know the API (application program interface), namely the protocol by which the driver software talks to the scanner. Making matters worse, not all APIs are published by the manufacturer: sometimes vendors publish only the basics and keep the good ones for their own use, or make them available only by license, to protect their intellectual property.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
From my experience with VueScan when scanning black and white negatives.
When setting the Output to Raw even if you make any additional changes to exposure, curve adjustments etc, those adjustments are not carried over when you press scan.
The scanned image (negative) should have a gamma encoding of 1.0. When importing to Photoshop, it should be assigned the same gamma value of your grey working space (gray gamma 2.2)
Now, the image needs to be inverted from a negative to a positive and this is where things in my opinion can get tricky. A simple invert does not seem to do a very good job but the ColorPerfect plugin on the other hand does a very good job with the inversion.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Jeez all the years I've been scanning, I've been scanning RAW... but no clue what gray gamma PS is set at. I'll have to check when I get home.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
I believe the default is Gray Gamma 2.2, but you might want to double-check your settings.
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2 Attachment(s)
Re: Update to Epson scanning article: how to bypass all tonal adjustments
I'm not sure if it's different because I have a PC, but putting the sliders to the ends makes the preview go black. So flat, it's not linear, but flat black. I can sorta get what you have shown by moving the white slider a little left to the start of the histogram highlights. Just a minor gotcha, but I know what you're doing and do something similar to your normal procedure but adjust gamma in PS. I do each color separately as my negatives are pyro stained and blue/red get shifted a little.
Attachment 173505Attachment 173506
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ken Lee
You're welcome and I very much appreciate the helpful information shared by others here and elsewhere. Ted has provided several valuable missing links.
I've done very little scanning of color materials: hopefully there are tutorials on the web which cover the issues. Positives are hard enough, but negatives are more challenging because we never know what they "really" look like unless we scan a calibration target (hint hint).
Being merely a consumer of these consumer-grade Epson scanners, it's not clear to me whether any adjustments we make via scanner drivers affect the process before image acquisition (aperture, exposure time, lamp brightness in physical terms or gain or other attributes in electronic terms) or whether all the adjustments we request are performed in software, after image acquisition. To be certain, you'd have to know the API (application program interface), namely the protocol by which the driver software talks to the scanner. Making matters worse, not all APIs are published by the manufacturer: sometimes vendors publish only the basics and keep the good ones for their own use, or make them available only by license, to protect their intellectual property.
Ken: I use a V600 with Epson Scan software. I have never used other scanner software.
My take is that all changes are done after the scan. Basically we're dealing with post scan processing that could be done with Photoshop or Lightroom or whatever. The point is the hardware is designed for the highest dMax. Assuming the program can change the amplification of the sensors or the amount of light output, it would have to be less than the standard operating scanner settings set to maximum or best. That would make shadows area darker. No point in doing that.
Increasing the light, even if possible, doesn't make sense either. You have to assume Epson designed and constructed the machine to give us the best dMax with the sensors and light they furnished. Why would they give us less? So you can't really raise the light output or increase the sensor amps without distortion.
The other giveaway to me that adjustments are all in post is when you do a test scan. You can play with the settings and get examples of what you will get once you do the actual full scan. The only way the program can give you those examples is by processing the test quick scan in software. So it seems, they do exactly the same thing after the full scan - software processing. Frankly, the argument other scanner programs are doing something more than Epson during the scan is sales promotion. If you like scan programs that you can "post" adjust when scanning, fine. But you can't get blood from a turnip. Why learn a second post processing program after learning PS or LR?
The only question about a settings that might be useful is by setting the black and white points (levels) to where the actual data starts and ends. That may give you more data of the parts of the film that actually contain something. But I'm not sure of that. It might make no difference by leaving levels at 0 and 255. When I try it both ways, it appears to be no difference. But some people have claimed there is a difference. I;m not sure about this. Maybe someone has an explanation of what we get with level settings.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
By test quick scan in my previous post, I meant preview scan.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
jp
I'm not sure if it's different because I have a PC, but putting the sliders to the ends makes the preview go black. So flat, it's not linear, but flat black. I can sorta get what you have shown by moving the white slider a little left to the start of the histogram highlights. Just a minor gotcha, but I know what you're doing and do something similar to your normal procedure but adjust gamma in PS. I do each color separately as my negatives are pyro stained and blue/red get shifted a little.
Attachment 173505Attachment 173506
First, the negative appears very dark, hence it's black with 0-255. My scans of good negatives are usually more to the left side. However, if you try moving the left slider in post just to the left of the start of data, you should find the results has the same brightness and contrast as if you did it with the Epson Scan during the scan process. The reason is like I said in my last two posts. The Epson software is just applying Levels to the resultant scanned file just like you would with a post processing program applied to a flat scan.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
There seems to be much conflicting information.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Alan Klein
Ken: I use a V600 with Epson Scan software. I have never used other scanner software.
My take is that all changes are done after the scan. Basically we're dealing with post scan processing that could be done with Photoshop or Lightroom or whatever. The point is the hardware is designed for the highest dMax. Assuming the program can change the amplification of the sensors or the amount of light output, it would have to be less than the standard operating scanner settings set to maximum or best. That would make shadows area darker. No point in doing that.
Increasing the light, even if possible, doesn't make sense either. You have to assume Epson designed and constructed the machine to give us the best dMax with the sensors and light they furnished. Why would they give us less? So you can't really raise the light output or increase the sensor amps without distortion.
The other giveaway to me that adjustments are all in post is when you do a test scan. You can play with the settings and get examples of what you will get once you do the actual full scan. The only way the program can give you those examples is by processing the test quick scan in software. So it seems, they do exactly the same thing after the full scan - software processing. Frankly, the argument other scanner programs are doing something more than Epson during the scan is sales promotion. If you like scan programs that you can "post" adjust when scanning, fine. But you can't get blood from a turnip. Why learn a second post processing program after learning PS or LR?
The only question about a settings that might be useful is by setting the black and white points (levels) to where the actual data starts and ends. That may give you more data of the parts of the film that actually contain something. But I'm not sure of that. It might make no difference by leaving levels at 0 and 255. When I try it both ways, it appears to be no difference. But some people have claimed there is a difference. I;m not sure about this. Maybe someone has an explanation of what we get with level settings.
Excellent points and well stated... thank you !
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ken Lee
it's not clear to me whether any adjustments we make via scanner drivers affect the process before image acquisition (aperture, exposure time, lamp brightness in physical terms or gain or other attributes in electronic terms) or whether all the adjustments we request are performed in software, after image acquisition.
There are no direct controls available that affect the BEFORE image capture in Epsonscan unlike vuescan. In vuescan you can manual adjust the CCD exposure, time. You even measure it with your stop watch, if you use a gain of 2, it will take twice as long to scan the image, as the stepper motor slows down to accommodate the longer time. However like the moon landing, it's possible this is a fake but I doubt that it is ;) Like the shutter speed on you camera if you set it too long, you will blow the highlights.
As I said earlier, epson scan most likely sets this automatically in the preview. Manual control of exposure allows you to skip the preview stage, in vuescan.
You could actually test this in epson scan if you wanted too by scanning film that has a very dense base, and timing it. (There is another clever trick you can try too, put a matching film clip over the calibration area).
There is also the individual gain of the each channel, vuescan also allows you to control manually, my understanding is that this is analogue amplification, like changing the iso on your digital camera.
All of this is hidden in vuescan, unless you actually look for it, as it will do this function automatically, as I believe epsonscan does anyway.
I would suggest most probably aren't interested, if the automatic function works correctly, it's already complicated enough :)
Quote:
Originally Posted by
IanBarber
From my experience with VueScan when scanning black and white negatives.
When setting the Output to Raw even if you make any additional changes to exposure, curve adjustments etc, those adjustments are not carried over when you press scan.
That's the idea with raw, i.e. to remove all the digital transformations. Even if setup it up to do the inversion, the preview may be positive but the raw file will still be a negative. However the gain functions I mentioned above will affect the raw capture. There is also some tweaks to the raw mode, that will allow you some minor processing.
Some of the features in viewscan are woefull, but for certain things it very simple and efficient (if what it offers, matches what you want and you know how to use it).
All of his doesn't mean you can't achieve excellent/similar results with epsonscan, especially if you are doing ALL of your post processing later.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
That's the idea with raw, i.e. to remove all the digital transformations. Even if setup it up to do the inversion, the preview may be positive but the raw file will still be a negative. However the gain functions I mentioned above will affect the raw capture. There is also some tweaks to the raw mode, that will allow you some minor processing.
Does the Gain feature work with Epson scanners, I thought this was a feature of the Nikon scanners same as the Focus feature
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ted Baker
In vuescan you can manual adjust the CCD exposure, time. You even measure it with your stop watch, if you use a gain of 2, it will take twice as long to scan the image, as the stepper motor slows down to accommodate the longer time.
Could you please share where this is set ?
Quote:
Originally Posted by
Ted Baker
There is also the individual gain of the each channel, vuescan also allows you to control manually, my understanding is that this is analogue amplification, like changing the iso on your digital camera.
All of this is hidden in vuescan, unless you actually look for it
I see where we can affect the color balance of the 3 channels...
...but the raw file appears to be unaffected by changes to these settings. If both images are captured at the same time, during a single pass, could gain/exposure time be changed for one but not the other ? Isn't this color gain adjustment performed post-capture ?
I can't get any changes to color balance to result in a different raw file: whatever I do, the raw file looks the same. What have I overlooked please ? Thank you for your patience.
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1 Attachment(s)
Re: Update to Epson scanning article: how to bypass all tonal adjustments
I think Ted is referring to the Gain control on the Input Tab
Attachment 173512
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
IanBarber
Eureka !
Those options appear if we scan transparencies. And as promised, the scanner stepper motor runs slower when we set them to a higher value.
Eureka !
And as promised, the raw file becomes darker or lighter accordingly.
Thank you again for your patience.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Sometimes if I need to open up the shadows slightly, I will increase the brightness of the Green channel found under the Color Tab
This is with the Green brightness set to 1 (default)
https://www.ianbarberphotography.co.uk/lff/green-1.jpg
This is with the Green brightness set to 2
https://www.ianbarberphotography.co.uk/lff/green-2.jpg
Think of the red Green Blue brightness controls as gamma adjustment (middle slider in Photoshop levels)
https://www.ianbarberphotography.co....brightness.jpg
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Good discsussion folks. Ian or Ted, are you using color negative film with any of your scanning work? The ideas on setting gain or gamma for each channel are interesting to me. It seems consistent with the different speeds/responses of the several color emulsion layers in C-41 film. I can see this difference in the histograms in Epson Scan and in post.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
jp
I'm not sure if it's different because I have a PC, but putting the sliders to the ends makes the preview go black. So flat, it's not linear, but flat black. I can sorta get what you have shown by moving the white slider a little left to the start of the histogram highlights. Just a minor gotcha, but I know what you're doing and do something similar to your normal procedure but adjust gamma in PS. I do each color separately as my negatives are pyro stained and blue/red get shifted a little.
Attachment 173505Attachment 173506
This isn't because you're using a PC, it's because you're scanning a transparency. If I scan a transparency on my Mac I get the same black image once I move the right slider too far to the right.
In my previous tests I scanned a reflective image: apparently the interface gives different results depending on what we're scanning. Arghhh !
Making matters worse, the 3 tools (Histogram Adjustment, Tone Correction and Image Adjustment) appear to have a cumulative effect. Using one doesn't override the other.
Therefore, when scanning transparencies with Epson Scan software, I can't find a way to bypass corrections at all.
As Gomer Pyle used to say, "Surprise, surprise" !
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ken Lee
Eureka !
Those options appear if we scan transparencies. And as promised, the scanner stepper motor runs slower when we set them to a higher value.
Eureka !
And as promised, the raw file becomes darker or lighter accordingly.
Thank you again for your patience.
Yes, thems the ones. A hint is they are all under the input tab ;)
I can't do a screen print as I need to be connected to a scanner.
These are slope adjustments (in linear colorspace), i.e. 2X will have twice the changes to the highlights (numerically), as opposed to the shadows, just like changing the ISO on your camera. (2x 50% becomes 100%, 18% becomes 38%, 5% becomes %10 etc)
With the color gain, it's possible this is being faked (done after the ADC), but the scanner has this capability, it does this every time automatically as the ccd goes over the calibration area, put a colour film clip over this area and see how it affects the results.
I don't know what the stuff on color tab actually does, other than to set it to leave everything alone, other than the sRGB adjustment. (But it's ignored completely when raw scanning which is what I do). All the stuff under the color tab is post scan processing that can be done somewhere else.
Quote:
Originally Posted by
chassis
The ideas on setting gain or gamma for each channel are interesting to me.
Be a little carefull here, lest you be come totally confused.;)
Quote:
Originally Posted by
Ken Lee
This isn't because you're using a PC, it's because you're scanning a transparency. If I scan a transparency on my Mac I get the same black image once I move the right slider too far to the right.
...
Therefore, when scanning transparencies with Epson Scan software, I can't find a way to bypass corrections at all.
As mentioned previously an inversion is by definition a tonal change. How this works is potentially unique to each program. This is very obvious when you try and work in color. Each program works their magic or NOT :D
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
chassis
Good discsussion folks. Ian or Ted, are you using color negative film with any of your scanning work? The ideas on setting gain or gamma for each channel are interesting to me. It seems consistent with the different speeds/responses of the several color emulsion layers in C-41 film. I can see this difference in the histograms in Epson Scan and in post.
I cannot speak for Ted but I personally only scan black and white film
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1 Attachment(s)
Re: Update to Epson scanning article: how to bypass all tonal adjustments
Ian, I copied your first darker picture and applied lightening to the shadows in PS Elements and got basically the second picture. So basically, it's just a post processing edit that the scanner is doing, not magic during the scan.
Attachment 173540
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Ken Lee
This isn't because you're using a PC, it's because you're scanning a transparency. If I scan a transparency on my Mac I get the same black image once I move the right slider too far to the right.
In my previous tests I scanned a reflective image: apparently the interface gives different results depending on what we're scanning. Arghhh !
Making matters worse, the 3 tools (Histogram Adjustment, Tone Correction and Image Adjustment) appear to have a cumulative effect. Using one doesn't override the other.
Therefore, when scanning transparencies with Epson Scan software, I can't find a way to bypass corrections at all.
As Gomer Pyle used to say, "Surprise, surprise" !
If you want to scan without any adjustments with Epson Scan, uncheck all boxes. Then click on the Configuration button at the bottom. When it switches to the Configuration page click on the No Color Corrections. The scan. Then do all your changes on the resultant "flat" file with your post processing program.
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Re: Update to Epson scanning article: how to bypass all tonal adjustments
Quote:
Originally Posted by
Alan Klein
Ian, I copied your first darker picture and applied lightening to the shadows in PS Elements and got basically the second picture. So basically, it's just a post processing edit that the scanner is doing, not magic during the scan.
Ah, so the scanner software must be just applying some form of curve adjustment