Guidance with scanning B&W slides with Plustek OpticFilm 8200i + Vuescan

[josephchesshyre]

Hello,

I've posted a few times in the analogue workflow forums but am new in this section. I shoot 35mm B&W which I process myself into slides using the reversal process. I like to be able to have digital copies and until now have been using a Panasonic Lumix bridge camera to do this, with, as you'd expect, OK but pretty mediocre results. I've recently acquired a Plustek OpticFilm 8200i and am trying to optimise my workflow with it. I really didn't like the interface of the Silverfast software that was bundled with it, so decided to get VueScan (pro edition). I'm quite happy with the results, but I know they can be improved and some aspects of the way it (and the scanner) render my slides are confusing me. Since B&W slides are pretty niche, as you'd expect there's not a great deal of information about doing this. (Despite this, VueScan does actually have a setting for 'REVERSAL B&W' although I'm not sure what the specifics of this are). Of course some of the principles of the process are the same as for colour slides, or at least more similar to this than to scanning negatives.

Although I'm pleased with the detail captured by the scanner, I'd been finding that almost all my slides were being rendered too dark, with not nearly as much shadow detail as there should be. I came across this page http://www.kennethleegallery.com/html/scanning/index.php which says that for a flat scan in VueScan one should adjust various of the 'Color' settings (not all of which are to do with colour!) from their default settings. One of the things it suggests doing is changing the default 'Curve low' and 'Curve high' settings from 0.25 and 0.75 respectively to 0.001 each, and also slightly raising the brightness from 1 to 1.06. Doing this resulted in scans that I was much happier with and seemed much closer to how the slides look projected or in a slide viewer.

However, because I like to know how and why I'm doing things, beyond just 'if it looks right then it is right' (valid though that is), I've been investigating further and have found that in fact the 0.25 and 0.75 settings for the curve is 'straight', and that adjusting them to their minimum values as that page suggests in fact expands the shadows and compresses the highlights. See here:


and here


However, as I say, with the curve points set to 0.25 and 0.75, I am seeing scans that are darker and are more contrasty than they should be. Is it at all possible that the supposedly straight curve in VueScan is actually applying a certain amount of contrast, as might well be necessary for a satisfactory scan of a negative, or that the scanner is doing this?

I am using the Lock Exposure and Multiple Exposure settings, by the way. I should also add that I have mainly been scanning Rollei Retro 80S and 400S, which are both contrasty films, especially the 400S – perhaps this is part of the issue?

Sorry for all this wordiness but I hope what I've written makes sense. Any tips from anyone who's managed to nail the process of scanning slides (especially B&W ones) with a Plustek scanner and/or VueScan software would be hugely appreciated. At the moment I'm keeping raw copies of the scans so that I don't have to go back and re-scan everything if I find some revolutionary change of settings that gives better results!

Thanks in advance.

 

[shutterfinger]

I have found Vuscan's settings convoluted and confusing. I turn auto everything I can off and save a raw scan then edit it in post. I have a plustek 7200 and 7600 in storage.
In post the histogram of the raw scan before editing should have the blacks starting between 0 and 25 and the highlights ending between 200 and 255. The subject matter will dictate the extremes but properly developed film will fall into this range.

 

[josephchesshyre]

In post the histogram of the raw scan before editing should have the blacks starting between 0 and 25 and the highlights ending between 200 and 255. The subject matter will dictate the extremes but properly developed film will fall into this range.

Do you mean even before black and white points are set? Because however much I manually adjust the exposure (even up to maximum, '200', in VueScan), my highlights are only halfway up the range on the raw histogram in VueScan. I do develop my slides on the dark side as I prefer this for projection, but the highlights (when they should be) are nevertheless clear so I should be getting much higher white values, surely?

Here's the histogram of the raw read-out after scanning with the exposure automatically set for a slide containing areas of clear film:


Frustratingly, as I watch the second (supposedly overexposed) scan take place for Multiple Exposure, I think 'yes! that's how it should look', so I know the scanner is physically capable of scanning at the right exposure, and I'm sure I'm just doing something wrong.

Here's an example of a quite dark scan with no black or white point adjustments (whose histogram is the one above):


And here's the same image with the white point adjusted:

 

[shutterfinger]

This is the histogram of your RAW scan as seen by Photoshop CS5 levels

As you can see this matches the histogram in Vuscan. This says to me that the film is under developed. Exposure determines the shadow detail, development determines the highlight detail. I suggest a 10% to 15% increase in development or more as a solution.
Scan in 48 bit RGB and save the raw scan. It has been reported that the blue channel gives the best detail.
This is the levels adjustment histogram for the adjusted image

and the adjusted image

 

[MattKing]

This says to me that the film is under developed. Exposure determines the shadow detail, development determines the highlight detail.

This is accurate for negatives, but may need to be revised to take into account that these are black and white slides.

 

[josephchesshyre]

This is accurate for negatives, but may need to be revised to take into account that these are black and white slides.

Thank you both, and I was just going to say this. It's sort of the other way round with slides, to some extent, but it's more complex as there is silver halide solvent (potassium thiocyanate) in the first developer, and also the film base's clarity or lack of it determines clearest available Dmin. In this case, FP4+ doesn't have a totally clear base, so you can in theory never get absolutely clear highlights.

Although neither the exposure nor the development are spot on here, the point is that the slide in a viewer, projector, or just held up to the light is nowhere near as dark as that raw scan. So why is the scanner choosing that exposure?

 

[josephchesshyre]

I'm beginning to think that this scanner just doesn't like slides which are a little bit too dark. The exposure seems to work fine with slides which are similar contrast but a bit lighter than this one. Also, I've discovered by reading through various discussions about VueScan that the raw image will always look darker because it isn't gamma adjusted. I'm still trying to learn exactly what this means...well I know what it means, but I don't quite understand why gamma adjustment is necessary.

I think I'm also in the process of learning that scanning slides while also still learning to develop them means that the post-scanning adjustments will vary quite a bit. Also, for whatever reason, I think projection allows a greater range of average densities to be acceptable whereas scanning is less forgiving.

 

[MattKing]

One thing that it is imperative to understand is that there is no scanner and scanning combination that will yield only files that need no adjustment.
Every attempt to make the results automatic will result in at least some results that are off. Unless, of course, all of your slides are exactly the same.
Scans are like negatives - you need to expect to have to adjust your approach to them to get what you want from them. What you want is scans that can be adjusted for the results you want.

 

[shutterfinger]

Somewhere in Vuscan, I think its under the color tab, you can turn auto exposure off which will give a better raw scan. With exposure adjustments off you get the full scanner output not an adjusted one.

 

[KenS]

Hello,

I've posted a few times in the analogue workflow forums but am new in this section. I shoot 35mm B&W which I process myself into slides using the reversal process. I like to be able to have digital copies and until now have been using a Panasonic Lumix bridge camera to do this, with, as you'd expect, OK but pretty mediocre results. I've recently acquired a Plustek OpticFilm 8200i and am trying to optimise my workflow with it. I really didn't like the interface of the Silverfast software that was bundled with it, so decided to get VueScan (pro edition). I'm quite happy with the results, but I know they can be improved and some aspects of the way it (and the scanner) render my slides are confusing me. Since B&W slides are pretty niche, as you'd expect there's not a great deal of information about doing this. (Despite this, VueScan does actually have a setting for 'REVERSAL B&W' although I'm not sure what the specifics of this are). Of course some of the principles of the process are the same as for colour slides, or at least more similar to this than to scanning negatives.

Although I'm pleased with the detail captured by the scanner, I'd been finding that almost all my slides were being rendered too dark, with not nearly as much shadow detail as there should be. I came across this page http://www.kennethleegallery.com/html/scanning/index.php which says that for a flat scan in VueScan one should adjust various of the 'Color' settings (not all of which are to do with colour!) from their default settings. One of the things it suggests doing is changing the default 'Curve low' and 'Curve high' settings from 0.25 and 0.75 respectively to 0.001 each, and also slightly raising the brightness from 1 to 1.06. Doing this resulted in scans that I was much happier with and seemed much closer to how the slides look projected or in a slide viewer.

However, because I like to know how and why I'm doing things, beyond just 'if it looks right then it is right' (valid though that is), I've been investigating further and have found that in fact the 0.25 and 0.75 settings for the curve is 'straight', and that adjusting them to their minimum values as that page suggests in fact expands the shadows and compresses the highlights. See here:


and here


However, as I say, with the curve points set to 0.25 and 0.75, I am seeing scans that are darker and are more contrasty than they should be. Is it at all possible that the supposedly straight curve in VueScan is actually applying a certain amount of contrast, as might well be necessary for a satisfactory scan of a negative, or that the scanner is doing this?

I am using the Lock Exposure and Multiple Exposure settings, by the way. I should also add that I have mainly been scanning Rollei Retro 80S and 400S, which are both contrasty films, especially the 400S – perhaps this is part of the issue?

Sorry for all this wordiness but I hope what I've written makes sense. Any tips from anyone who's managed to nail the process of scanning slides (especially B&W ones) with a Plustek scanner and/or VueScan software would be hugely appreciated. At the moment I'm keeping raw copies of the scans so that I don't have to go back and re-scan everything if I find some revolutionary change of settings that gives better results!

Thanks in advance.

Joseph,
I'm too am somewhat new to scanning.. however I just do a B?W 'scan', open the file in Photoshop andadjust 'black and white point' contrast and 'play with the possible adjustments'
But then I'm scanning ONLY 4x5 negative developed in Pyrocat HD. (no 'obvious 'stain) I don't know if there are any 'adjustments' readily available only using only the ViewScan software
I could send you a link to some of my images on the 5x4.co.uk website should you be anywhat interested. I don't depend on Viewscan to the final adjustments I feel necessary... I 'think' Photoshop (or whatever) might be an 'easier means of 'getting to where you want to 'be'

Ken

 

[destroya]

get a copy of the vuescan bible. its a good reference guide to the app and answers a lot of questions. I found a copy at the local library as well as the PDF online.

 

[shutterfinger]

http://temp.fotoluzr.net/board/doc/Rocky.Nook.VueScan.Bible.Jun.2011.pdf

This is accurate for negatives, but may need to be revised to take into account that these are black and white slides.

Then increase exposure 1/2 to 1 stop.

 

[Patrick Robert James]

I have a Nikon scanner that I use Vuescan with but the settings should be similar.

To do a negative, first I lock the exposure on the margin. Then I set the curve levels at .3 and .7. I usually set both the black and white clipping levels to .02 for batch scanning. For individual scans I'll move them higher until I see clipping then back them off. I rarely adjust the brightness unless I have a problem neg, but I don't get too many of those really.

You should really get the scan right. Lots of tutorials out there say you should scan flat, but that is generally not a great idea. If you are one of those paranoid types then you can do a raw scan and output it as a dng if I am not mistaken. I've never done that though. Good ol' 16 bit TIF has always worked for me.

 

[PhilBurton]

I have a Nikon scanner that I use Vuescan with but the settings should be similar.

To do a negative, first I lock the exposure on the margin

Do you mean the space between exposures? For batch scanning?

. Then I set the curve levels at .3 and .7. I usually set both the black and white clipping levels to .02 for batch scanning. For individual scans I'll move them higher until I see clipping then back them off. I rarely adjust the brightness unless I have a problem neg, but I don't get too many of those really.

If you batch scan, do you often feel that you need to re-scan individual images at different settings? Why?

You should really get the scan right. Lots of tutorials out there say you should scan flat, but that is generally not a great idea.

Why is that?

If you are one of those paranoid types then you can do a raw scan and output it as a dng if I am not mistaken. I've never done that though. Good ol' 16 bit TIF has always worked for me.

I assume that that DNGs refer only to Vuescan, not to Nikonscan or Silverfast? Correct?

 

[josephchesshyre]

Thanks, I've been looking through The VueScan Bible and it's great and exactly what I needed. Thanks for the PDF link as well.

What do we make of this btw (from the book)?

Are there any film scanners equivalent in price and performance to the Plustek 8200 that use a fluorescent light source?

Then increase exposure 1/2 to 1 stop.

Totally depends on the process. In mine if anything I have to underexpose slightly. A lot of that depends on the quantity (or absence) of silver halide solvent in the first developer, which serves partly to increase speed.

To do a negative, first I lock the exposure on the margin. Then I set the curve levels at .3 and .7. I usually set both the black and white clipping levels to .02 for batch scanning. For individual scans I'll move them higher until I see clipping then back them off. I rarely adjust the brightness unless I have a problem neg, but I don't get too many of those really.

In general, what's the rationale behind slightly clipping the blacks and whites rather than just leaving the levels at 0% in VueScan at both ends? Incidentally, the default settings in VueScan are 0% for the black point but 1% for the white point (i.e. the brightest 1% of pixels in the image are all made pure white). Similarly, what's the rationale for this?

 

[josephchesshyre]

One thing that it is imperative to understand is that there is no scanner and scanning combination that will yield only files that need no adjustment.
Every attempt to make the results automatic will result in at least some results that are off. Unless, of course, all of your slides are exactly the same.
Scans are like negatives - you need to expect to have to adjust your approach to them to get what you want from them. What you want is scans that can be adjusted for the results you want.

This is really very good advice and I am beginning to realise this. Also, one should be honest with oneself and realise when actually a slide is being tricky to scan because one is attempting to correct for either sub-par exposure or development or both!

 

[Wallendo]

The histograms you are getting are fairly common for unadjusted scans. I routinely scan with no scanner adjustments and then adjust the levels in PhotoShop. At times the shadows do seem to get crushed by this technique.
Since with B&W we don't have to worry about color shifts, there is no real problem with using the "Neutral" color scanner setting setting the black and white cutoff values at 0.1 or 0 - I usually use 0 for black and 0.1 for white - setting white at 0 can yield unexpected results if any dust is present on negative scans. I haven't tried scanning B&W slides yet, so you may want to try setting black at 0.1 instead.

 

[albireo]

Are there any film scanners equivalent in price and performance to the Plustek 8200 that use a fluorescent light source?

Yes - my Minolta Scan Dual III and my Plustek 7500i both use a fluorescent light source. Both yield - to me - really satisfactory results with 35mm bw negatives.

 

[josephchesshyre]

Yes - my Minolta Scan Dual III and my Plustek 7500i both use a fluorescent light source. Both yield - to me - really satisfactory results with 35mm bw negatives.

Oh brill, thank you. Do you think this makes enough of a difference for it to be worth my swapping my 8200i for a 7500i? I'll be using it for 95% B&W so if fluorescent light sources really are better for this then I will consider doing so.

 

[Kodachromeguy]

With your 8200i, did you get a license for SilverFast Ai software? If yes, please try it to control your scanner. I, too, had frustrations with Vuescan and use Silverfast exclusively now.

 

[josephchesshyre]

With your 8200i, did you get a license for SilverFast Ai software? If yes, please try it to control your scanner. I, too, had frustrations with Vuescan and use Silverfast exclusively now.

I did, but I bought VueScan because I found the Silverfast interface very unpleasant and it has masses of features I don't need, like software dust reduction, auto contrast etc., yet I found the controls I did need to use not nice to use. Each to their own of course.

 

[ced]

Try cropping the image to exclude anything outside the image area (there is a black edge at top right of your scan) then try the automatic analysis of the scan software, if no improvement adjust manually the end points to your satisfaction,
along with gamma correction to get the midtone as you like it. Tweak the rest in PS post scan...

 

[albireo]

Oh brill, thank you. Do you think this makes enough of a difference for it to be worth my swapping my 8200i for a 7500i? I'll be using it for 95% B&W so if fluorescent light sources really are better for this then I will consider doing so.

Hi again, unfortunately I do not own a 8200i so I'm unable to directly compare. What I can say is that my 7500i blows my Epson V550 flatbed scanner out of the water for 35mm (the V550 is great for medium format).

Regarding the 8200i with BW film - what makes it unsuitable for the task in your experience? A quick browse of the flickr 8200i' user group here

https://www.flickr.com/groups/2188725@N20/

seems to suggest that it can give nice results with bw film?

 

[PhilBurton]

With your 8200i, did you get a license for SilverFast Ai software? If yes, please try it to control your scanner. I, too, had frustrations with Vuescan and use Silverfast exclusively now.

Kodachrome guy,

Can I assume that you have/are scanning mostly Kodachromes? (Me too).

I haven't started my "big scan project" yet but I'm really torn between Vuescan and Silverfast. Most people seem to prefer Vuescan, and the price is certainly better. What is your reason for preferring Silverfast?

Phil

 

[Kodachromeguy]

Kodachrome guy,

Can I assume that you have/are scanning mostly Kodachromes? (Me too).

I haven't started my "big scan project" yet but I'm really torn between Vuescan and Silverfast. Most people seem to prefer Vuescan, and the price is certainly better. What is your reason for preferring Silverfast?

Phil

I tried Vuescan with my Minolta Scan Multi medium format scanner, but just could get it right. But I admit, I likely did not give it enough of a chance. When SilverFast offered a Christmas sale price, I bought a copy. I was already familiar with the Silverfast interface from previous scanners at work. And my Plustek 7600I 35mm scanner came with Silverfast as part of the purchase. It is a clumsy interface, but I know how it works.

Most of my scans are b&w film now, but occasionally some old K25 slides. When I retired, I thought I would have plenty of time for this stuff, but I am more than busy with my recent photo projects. In retirement, I am busier than ever! Where does the time go???