Plustek 120 scanner review

artobest

Member
Joined
Oct 19, 2011
Messages
165
Location
South Wales
Format
Medium Format
They (Plustek) claim 5300 true resolution (ie, the resolving power of the lens/sensor/motor combination), but this may only be gained if you choose the highest stepping resolution (10600 - that is, the finest incremental movement of the motor). I can't say for sure, since I don't have one and at current prices am unlikely to get one for a while, sadly.
 

StoneNYC

Member
Joined
Aug 5, 2012
Messages
8,345
Location
Antarctica
Format
8x10 Format

Hmm, I'll have to take your word on it, my Epson v750 maxes at 3200 for most fine grained films


Sent w/ iPhone using Tapatalk
 

Les Sarile

Member
Joined
Aug 7, 2010
Messages
3,426
Location
Santa Cruz, CA
Format
35mm
It may also be that it is not achieving optimal focus distance which is problematic since you cannot shim the filmholders and it doesn't have autofocus like the Coolscan. Of course if they got a bad sample then that is not comforting either.

It also lists a density of 3.2 compared to the Epson V750 at 4.0 and the Coolscan at 4.8. I have not actually conducted any tests on my own to see the differences in density so I am not sure how significant this is.
 

L Gebhardt

Member
Joined
Jun 27, 2003
Messages
2,364
Location
NH
Format
Large Format
Are you sure? I'm not trying to argue I just doubt it would be double what they claim.


Sent w/ iPhone using Tapatalk

Many scanners have an asymmetrical resolution like this. In one direction (perpendicular to the film holder movement) the resolution is limited by the CCD and it's relative size to the film, which in the case of the Plustek, gives you 5300ppi. Then in the direction that the scanner moves the film the resolution is determined by how small of a step the scanner can move the film or the scan head. In the case of the Plustek it looks like the stepper motor can move the holder at 10600 steps per inch. If you scan at 10600ppi each line will be offset by this amount, but across the coarser dimension the resolution will be determined by the CCD. To keep the image square the data from the CCD is interpolated (each pixel is doubled to give 10600ppi), but the scanner really does take a scan for each step so it's not interpolated in the other dimension. In any scanner like this the actual ability for the lens to project the image of the film perfectly in focus and sharply on the CCD is usually the limiting factor. In addition sometimes the film holder doesn't move precisely the same amount for each step. So the actual resolution is never going to match the resolution of the CCD or the step size.

In my testing of other scanners I haven't found it beneficial to scan at the highest resolution and then down size. There are sometimes slight improvements, but in the case of the Epson scanners you end up with file 16 times larger than it needs to be (9600ppi is over 4x the actual resolution of the system, then square that). This takes a lot of time to load and resize for at best a few percent more resolution. I suspect the Plustek is the same way in that any increase will be marginal and not worth the effort in most cases.
 

artobest

Member
Joined
Oct 19, 2011
Messages
165
Location
South Wales
Format
Medium Format
Hmm, I'll have to take your word on it, my Epson v750 maxes at 3200 for most fine grained films

Yes, and you need to scan higher to get that resolution, right? But when scanning at 6400, the extra pixels aren't interpolated, they're just, well, blur; rubbish pixels, if you like. The limiting factor is the lens, and maybe the glass platen, in combination with the problems in obtaining ideal focus.

3200 is pretty good for the V750, by the way.
 

StoneNYC

Member
Joined
Aug 5, 2012
Messages
8,345
Location
Antarctica
Format
8x10 Format

No I don't scan higher to get that, I scan at 3200...


Sent w/ iPhone using Tapatalk
 

pschwart

Subscriber
Joined
Jul 15, 2005
Messages
1,147
Location
San Francisco, CA
Format
Multi Format
Plustek seems to have filled the niche vacated by the Coolscan 9000 with a less capable unit at the same price point. That's a missed opportunity; I would even have paid more for a better unit, but I don't expect I will buy one of these Plusteks.
 

StoneNYC

Member
Joined
Aug 5, 2012
Messages
8,345
Location
Antarctica
Format
8x10 Format
Plustek seems to have filled the niche vacated by the Coolscan 9000 with a less capable unit at the same price point. That's a missed opportunity; I would even have paid more for a better unit, but I don't expect I will buy one of these Plusteks.

Should have made it 4x5 compatible

Why have two scanners for minutely more DPI (if you get a good one) lol.

Alas...

Wish I could see the difference on one of my own images...

I'm just surprised with all this technology we still can't get a good scan, it should be simple at this point, heck my iPhone camera is probably better than the one in these things, I don't get it... Lol


Sent w/ iPhone using Tapatalk
 

chuck94022

Member
Joined
Jan 11, 2005
Messages
869
Location
Los Altos, C
Format
Multi Format

Yes I assume you are tongue in cheek regarding the iphone.

Regarding my previous post, Stone, in fact I was serious that scanning at the minimum stepping motor increment is generally the way to assure getting the maximum resolution. Yes, that step will exceed the optical resolution, but is is precisely that procedure Plustek said they used to determine the 5300 ppi resolution. If the Scan-dig site did not run their test at that minimum step, they could not expect to achieve the same results as Plustek. The Plustek is not interpolating at the 5300 setting. It is my understanding that it is interpolating one dimension at 10600. But since the lens resolution has been exceeded at 10600, it is effectively duplicating pixels at that resolution in both dimensions. But if it is stepping at the 5300 setting, it is probably missing image data it can actually resolve.

I agree with you that the Epson v750 (which I also use) maxes out optically at about 3200 ppi. I have worked hard to dial mine in focus-wise with a betterscanning holder, and I also wet mount (I don't see a huge difference with wet mounting, but it does have subtle improvement).

Regarding density - no scanner does 4.8 or 4.2, and I doubt any actually achieve 4.0. That said, given the evaluation procedure scan-dig did, I don't trust their assessment of 3.2.

Surely you are joking about making it capable of 4x5. For most uses, the Epson is perfectly fine for 4x5 scanning, unless you are making billboards. On the other hand, a high quality drum scan of 4x5, even at the same resolution, by a skilled operator, can't be beat.
 

Les Sarile

Member
Joined
Aug 7, 2010
Messages
3,426
Location
Santa Cruz, CA
Format
35mm

According to my res testing of the Epson V7XX - using Fuji Velvia, test target, optimal setup and conditions, standard holder, the V7xx manages to achieve more detail at 6400dpi setting.
6400dpi - 6 vert, 5.5 horz
4800dpi - 5.5 vert, 5.5 horz
3200dpi - 4.5 vert, 5 horz
2400dpi - 3.8 vert, 3.8 horz
1200dpi - 2.2 vert, 2.2 horz

Full res -> Fuji RVP50-03_18 Epson V700

Let me be clear that this is not the same as saying that it achieves 6400dpi of actual detail because clearly, the same frame of film scanned with the Coolscan 5000 resolves much more at 4000dpi - 8.5 vert, 9 horz. For all intents and purposes, you can see the lines practically up to 10. In looking at this now, I may have been more conservative with the Coolscan then I am with the Epson.

Full res -> Fuji RVP50-03_18 Coolscan 5000


The V700 does resolve more than the V500 which maxes out at 2400dpi setting - 4 vert, 3 horz.

Full res -> Fuji RVP50-03_18 Epson V500


  • Please note that I only had one sample of these scanners so it is entirely possible I have a sub-optimal unit.

Regarding density published by ScanDig, did you read their site regarding this Density and density range of scanners
I haven't personally gotten around to conducting my own testing of density but have made some observations between the Epson and Coolscan and there are some differences. Have you?
 

StoneNYC

Member
Joined
Aug 5, 2012
Messages
8,345
Location
Antarctica
Format
8x10 Format

I was only half kidding about the iPhone images, however it should be understood that the new iPhone 5s camera and the lens elements that are contained within it are actually really really high-quality and precision made. Just very small.

Based on how variable the lenses in the scanners are, Visa V getting a good scanner or a bad scanner sometimes, it seems like the iPhone lenses and camera are actually more precise without any variation in quality from phone to phone. Trust me I hate to admit it because I don't want it to be so ... but it's true the iPhone camera is actually pretty decent.


Sent w/ iPhone using Tapatalk
 

chuck94022

Member
Joined
Jan 11, 2005
Messages
869
Location
Los Altos, C
Format
Multi Format

Well... yes, they are decent, if you are targeting a low resolution final output medium, like the web. An Epson v750 scanning a 35mm negative at 3200 ppi creates a 13 megapixel image, with 16 bits per channel, uncompressed lossless output. The iPhone 5s camera is an 8 megapixel camera, with 8 bits per channel, jpeg (lossy) output. Neither is great for much beyond the web and small prints, but clearly the Epson is technically superior.

A better scanner for 35mm is a Nikon D800e with a high quality lens. That would give you a 36 megapixel, 14 bit-per-channel image, lossless. And it would be faster than using the Epson. I sometimes do this for 35mm, but usually go with the Epson for other reasons, including being able to batch scan unattended using Silverfast. [Note: The resulting D800 image is not a true 36 megapixel scan due to the interpolation resulting from Bayer filtering. It is actually about 1/4 of the true resolution, but the interpolation algorithms are sufficiently good that you may not be able to detect the difference. But it is a reason to use a true scanner rather than a Bayer filtered camera. (The iPhone also uses a Bayer filter, so it is not actually a true 8 megapixel camera either.) The Epson is true pixels, reading each color at each pixel location, so its resolution is actual.]

Regarding scanners and quality - there is no such thing as a scanner that doesn't depend on operator skill. Any scanner will produce a bad scan if you just take defaults and don't understand the fine points of operation (including proper focusing, either manually or using auto focus, cleaning, mounting, etc.). The more sophisticated (ie, high resolution) the scanner, the more important it becomes that the operator develops skill with the device. It is also important to fully understand the relationship between scanning and follow-on post processing. Rarely is it ever the right choice for the scan itself to be the final product. Post processing is a critical element.

I've spent many hours dialing in my personal technique and getting flat, focused scans just with a simple Epson v750. With more sophisticated scanners, as much or even more care is required to get exceptional scans, which provide quality input for final post processing.

(Edited to add the Bayer filtering factor.)
 
Last edited by a moderator:

StoneNYC

Member
Joined
Aug 5, 2012
Messages
8,345
Location
Antarctica
Format
8x10 Format

You obviously know a lot more on the techy side of digital imagery, I've never understood the whole channel / bits thing. However the 8mp camera can output RAW files with a camera app so not sure how much improvement that makes, "645 Pro Mk II" is the name of the best app I can find reviews on but I don't want to purchase it till they get the iOS7 bugs out.

Anyway I am curios, perhaps I'll take two images one on film and one on digital of the same scenes and see how they compare.


Sent w/ iPhone using Tapatalk
 

chuck94022

Member
Joined
Jan 11, 2005
Messages
869
Location
Los Altos, C
Format
Multi Format

Thousands of webpages have been dedicated to that comparison... There are so many variables involved that in my opinion it isn't worth it.

Regarding channels and bits: a digital image is comprised of three channels: the red channel, green channel, and blue channel. Each pixel of the image has a red component, a green component, and a blue component. The number of "bits" used to represent a color determines how finely the color can vary. With 8 bits per channel, a single color can have 256 variations. (So you can get 256 shades of red in your image). With 16 bits per channel, a single color can have 65536 shades. That's a huge difference. But that difference really becomes important when you are editing your image during post processing, such as in Lightroom or Photoshop.

With images that are only 8 bits per channel, you will quickly get posterization (banding) as you adjust tones. With 16 bits per channel, you have more flexibility.

The second problem is with jpeg (compressed, lossy) images, versus raw (lossless) images. When editing the jpeg images during post processing, the smudges and such introduced by jpeg compression will be amplified, and frequently very noticeable in the final result. That is avoided with raw (lossless) images. Raw images give you everything the sensor saw. Jpegs are an interpreted image, and not recommended to be edited further.

To be accomplished with scanning, it is very important to understand these concepts. Your images will appreciate it!
 

StoneNYC

Member
Joined
Aug 5, 2012
Messages
8,345
Location
Antarctica
Format
8x10 Format

Thanks that was thorough and succinct
 

artobest

Member
Joined
Oct 19, 2011
Messages
165
Location
South Wales
Format
Medium Format
@Les, I'd like to see your results using the betterscanning holder. The OEM holder is irrelevant, IMO. It just doesn't deliver what the machine is capable of.
 

Les Sarile

Member
Joined
Aug 7, 2010
Messages
3,426
Location
Santa Cruz, CA
Format
35mm
artobest, You consider the Epson OEM holders irrelevant because:
  • More Epson users are using it then the OEM holders?
  • Or that it provides a verifiable difference?
 

StoneNYC

Member
Joined
Aug 5, 2012
Messages
8,345
Location
Antarctica
Format
8x10 Format
artobest, You consider the Epson OEM holders irrelevant because:
  • More Epson users are using it then the OEM holders?
  • Or that it provides a verifiable difference?

Your question doesn't make sense? You mean more people are using the OEM holders than the betterscanning ones?

I think they are irrelevant because they are useless and don't produce an even enough film plane to even bother using them, in particular 120, or even slightly curly 35mm, but the 4x5 holders are ok.

The betterscanning ones are way better.
 

Les Sarile

Member
Joined
Aug 7, 2010
Messages
3,426
Location
Santa Cruz, CA
Format
35mm

Probably because I didn't quote artobest's response stating, "@Les, I'd like to see your results using the betterscanning holder. The OEM holder is irrelevant, IMO. It just doesn't deliver what the machine is capable of." as he is the one who stated - and now you too, that Epson's holders are irrelevant because they are apparently not optimal.

I have conducted the test using only the provided holders as I am sure most all Epson users do and I don't have the other holder. If you do, I can certainly send you the same frame of film to test and we can all know how much it may improve on the Epson holders.
 

artobest

Member
Joined
Oct 19, 2011
Messages
165
Location
South Wales
Format
Medium Format
Les, for some lucky users, the OEM holders will be optimal - there's just no way of knowing for sure because the adjustments are far too coarse. What I will say is that, for me, the betterscanning holders were a huge leap in resolution over the OEM holders set to their best position. The difference was not small. That is why I don't feel that testing using the OEM holders does the Epson justice, and that is why the resolution of this machine is consistently underestimated in tests.
 

Les Sarile

Member
Joined
Aug 7, 2010
Messages
3,426
Location
Santa Cruz, CA
Format
35mm
Artobest, Seems that StoneNYC has the Epson V7XX and betterscanning holder so it would not cost much to send the same frame for more testing.
 

StoneNYC

Member
Joined
Aug 5, 2012
Messages
8,345
Location
Antarctica
Format
8x10 Format
Sure I'm down, I use the epson scan software and NOT SilverFast/Viewscan hope that's ok?

PM me if you're serous, I live in the USA in the New England area
 

artobest

Member
Joined
Oct 19, 2011
Messages
165
Location
South Wales
Format
Medium Format
Les, I don't know what country you're in - I'm in the UK if that's more convenient. PM me.
 

Les Sarile

Member
Joined
Aug 7, 2010
Messages
3,426
Location
Santa Cruz, CA
Format
35mm
I just added my location. StoneNYC, just to be sure you have the betterscanning holders. From all the test I have done, I don't believe I have encountered any resolution related issues caused by the use of software. Issues with colors, contrast and proper ICE perhaps but never resolution. I recently shuffled my film storage around but I should be able to find the frames of film for this test and I will PM you. Artobest, it doesn't hurt to have additional sets of eyes on it and I doubt shipping to you would be prohibitive. I think this would be helpful to quantify just how the betterscanning holders can affect the results.
 

chuck94022

Member
Joined
Jan 11, 2005
Messages
869
Location
Los Altos, C
Format
Multi Format
The betterscanning holders require a dedicated "dial-in" effort to ensure that the mounted film is in the plane of sharpest focus. It took me an afternoon of repeated scans to get it right.

Once that is done, getting the highest quality scans still requires understanding the craft of scanning. I would suggest, Les, that you provide Stone some detailed instructions on how the scan should be captured (resolution, output format, filter settings, curve settings, etc. etc.).

Bottom line is the holder by itself won't perform magic if you don't have the rest of the process mastered.

It will also depend on the care and feeding of the particular Epson. If the glass is not sparkling clean, if there is dust inside the device, all this affects the result.

I doubt the test will tell much unless the exact same process is done on the same Epson using the OEM holders and well dialed-in betterscanning holders.

If it is any help, I too would be happy to conduct some test scans. I just need the targets (assuming the scans would be done using Les' beautiful resolution targets).