Plustek 7400 curious observation or what?

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Just got a Plustek 7400. All drivers up to date, latest software updates installed.

But, compared to my Epson V700 the dynamic range of the Plustek seemed really poor using Silverfast when scanning a known and previously scanned B&W negative. The shadows block in and no amount of fiddling with the histogram or other settings solved it. So I tried Vuescan and the same thing happens (and its actually a worse scan with less latitude than Silverfast anyway). Tried multi pass, multi exposure, and as many variables as I knew how. So, wondering what else to do I simply reverted to SF and changed the 'Negative' to 'Positive' in the menu, then tried again. And lo and behold I get all the shadow detail back by scanning as a positive! I then have to invert the image in Photoshop but that isn't a chore.

I'm obviously missing something fundamental, so why would scanning a B&W negative as a negative give a poor dynamic range when simply switching to scanning it as a postive and leaving all other settings the same gives me back my shadow detail?

Yours baffled
Steve
 
Same experience here.
All my Plustek scans are also at least 2 stops brighter compared to my Epson V700 scans of the same negative. Way overexposed and almost blown, where my negatives are not!!
Negative scans with Silverfast only work reasonable for the films where a profile is included to set in the software.
I wil stick to simple straight positive scans with Silverfast and adjust from there in Photoshop.
Real pity is the 8 instead of 16 bit output of the files using Silverfast.

Wished i could use Epson San software with my Plustek.
 
Just got a Plustek 7400. All drivers up to date, latest software updates installed.

But, compared to my Epson V700 the dynamic range of the Plustek seemed really poor using Silverfast when scanning a known and previously scanned B&W negative. The shadows block in and no amount of fiddling with the histogram or other settings solved it. So I tried Vuescan and the same thing happens (and its actually a worse scan with less latitude than Silverfast anyway). Tried multi pass, multi exposure, and as many variables as I knew how. So, wondering what else to do I simply reverted to SF and changed the 'Negative' to 'Positive' in the menu, then tried again. And lo and behold I get all the shadow detail back by scanning as a positive! I then have to invert the image in Photoshop but that isn't a chore.

I'm obviously missing something fundamental, so why would scanning a B&W negative as a negative give a poor dynamic range when simply switching to scanning it as a postive and leaving all other settings the same gives me back my shadow detail?

Yours baffled
Steve

Do you mind to show some photos here?
 
Not just me then!

As I say cabbiinc, Vuescan does exactly the same thing, the shadows block in and its all far to bright. At least with Silverfast you get a properly adjustable histogram with a mid-tone slider and don't have to phaff about with black points etc. I've had Vuescan on every PC for ten years now, with various scanners, and never warmed to it. What you see isn't what you get. The frustration is that I like a nice flat scan (with all the information which can be adjusted to the final image in Photoshop). And this is exactly what I see when the Preview has just finished running, everything is there from shadow detail to highlight detail, and then a second later Vuescan goes and applies some processing and everything is blown out. Or I adjust the Preview under the 'Color' tab, black points, white points, high and low curves, and it is near where I want it. I make a scan and the damned thing is back to square one ignoring the adjustments I have made. I don't pretend to understand Vuescan even after all this time, and admit I don't understand why people think it is so good, but I'm still willing to learn what I'm doing wrong. In the meantime I'm thinking Silverfast gets an unnecessarily bad press.

Steve
 
Do you mind to show some photos here?

Of blown out blacks, I don't understand what that is going to show? The Histogram in both SF and Vuescan has the blacks going off the scale to the left with no adjustments possible when scanning as a negative, but scan the negative as a positive (even with default settings) and the blacks are well inside the histogram. That is the anomaly, not the end photograph.

Steve
 
And this is exactly what I see when the Preview has just finished running, everything is there from shadow detail to highlight detail, and then a second later Vuescan goes and applies some processing and everything is blown out.
OK, I've seen this behavior before and here's my observations which I think you can apply to either Vuescan or Silverfast or ....
When you use a low dpi for the preview scan the program doesn't get enough information at the pixel level. You choose something that looks good for that pixel count and press scan and the program applies the settings for the lower pixel count to the higher scan pixel count and that doesn't work. Try previewing at a higher pixel count. Either that or don't apply any settings until you do a scan at the resolution that you'll save at. In Vuescan you can click "Scan From Preview" in the Input tab. The "preview will be at the resolution the scan is and when you actually press scan it just sends the image to the output of your choosing.

In Vuescan, if you just want What You See Is What You Get then changing the Color Balance to Neutral in Vuescan should give you that. The best results I get from Vuescan are with Auto Levels for most day lit shots, White Balance for most indoor shots, and usually Manual for nightscapes (then right clicking a white light source) but Auto Levels usually is usable too.

Also on the Crop tab set the Buffer % to 10 or above. Otherwise any vignetting is included in the corrections calculations.

With Vuescan leave the film profiles to generic. Leave most everything that I haven't mentioned to defaults unless there's really a need to change it. They're included for those that like to fiddle with too many settings.

But the first thing I would try is setting a larger dpi for previewing in Silverfast seeing as that program agrees with you.
 
I've learned to make the initial adjustments, scan, then fine tune the raw image before saving. This way I'm working with the actual scan, not the preview. And it also allows me to try multiple versions of the same scan.
 
OK, I've seen this behavior before and here's my observations

Its so simple when you know how! Thank you very much. I've nailed it with Vuescan and most of all now see what the problem was following your great advice for the settings. And Silverfast will have to take a back seat because with the poor mans version I can't change the Preview dpi. I owe you a drink!

Steve
 
I'm glad you got it figured out. Nuts about Silverfast though. It's a shame when you get something you like then find out that, to borrow a phrase, "missed it, by that... much...".

Dan
 
Ok, I've done some testing with my new Plustek 7400 and Silverfast-8 software. Just as OP described my first b&w scan results were awful. Much, much too contrasty. I soon found out the main reason for the high contrast are film profiles. I'm sure they are great with color negs but for b&w negs they just don't work. So, don't use them. For b&w negs I'm using <Other>, <Other> and <Linear> or <Standard> as my default choices for the film profile. One thing is to check and re-check your histogram. If you alter your histogram it won't go back automatically. You need to reset it manually.

For scanning I choose Multi Exposure (ME) and HDR 16bit, do the prescan first and then the real scan in 3600dpi as .tiff. What you get looks really awful because it's a 16bit positive .tiff file and actually a RAW scan. Don't give up just yet. What you need to do first is to invert the file (Ctrl+I in Photoshop) and then apply the "Auto Contrast" command. Now you have a very nice 16bit base scan to work with. My tests reveal the Plustek 7400 can do not quite but almost as fine scans I got out of my previous Coolscan 5000ED.

I hope this helps.
 
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