Czur ET24 Pro first impressions

Built a scanner? Started to build a scanner? Record your progress here. Doesn't need to be a whole scanner - triggers and other parts are fine. Commercial scanners are fine too.

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aestetix
Posts: 26
Joined: 06 Sep 2021, 13:47
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Country: United Kingdom

Czur ET24 Pro first impressions

Post by aestetix »

I bought a Czur ET24 Pro from Indigogo after hearing good things about them.

Setting up the scanner was easy and it was well presented in the packaging. Software installation went smoothly.

I started with a paperback of nearly 200 pages. Results were terrible. After some experimentation I got the lighting in the room right so that the scanner would filter out the black mat they give you to scan on. Even so, using the finger cots the software would often detect my hand and fail to crop the page properly.

Scan quality was poor. The book's paper was slightly shiny so sometimes got reflections off the ET24's light. You really need separate lighting for this kind of paper. Even when it did work, the image was often distorted and poorly cropped. The software also fails to properly rotate some pages, leaving them a degree or two off. You can only rotate by increments of a degree, not really fine enough.

I tried some manual editing to improve it, and in some cases could. In other cases it was beyond saving. I gave up and moved on to a hardback with a little under 1000 pages.

Initial results were better. Often pages come out well cropped and with good image quality. I found it really helps to have something under the slide of the book that is raised up by the spine for the first pages where the spine makes it hard to lay flat. Even so, the image quality was less than satisfactory in some cases. At least the cropping was mostly good.

I think the scanner would benefit from a V shape stand here.

Unfortunately after a few dozen pages I gave up. The software is unstable and crashes every few minutes. I send reports to Czur, I'll see if they can fix it. My PC is stable and I tried another machine just to be sure, with the same result. I'm running Windows 8 and 10. Maybe it's better on Linux.

Speaking of the software, it's a bit awkward but functional. It's a shame it can't auto detect the divide between pages, you have to manually align them. That would be a huge time saver.

If they can't fix the software I'll return it or sell it, and stick with destructive methods.

Edit: Here are some example images.
image00001.jpg
First, a book cover showing uneven lighting.
image00009.jpg
Shine from the scanner's lights.
image00010.jpg
Wonky, didn't remove the finger cot very well, and didn't crop the page properly. The tools in the software to correct this are inadequte.
image00022.jpg
Using the finger cot the cropping is wrong and includes my arm. This happens a lot. The cot removal is also pretty poor.
image00034.jpg
What ISN'T wrong with this? It's wonky, none of the text is straight. The bit where it says "Drive Letter" near the top is actually white text on a black bar background, and the software screws it up.
image00001.jpg
Another cover, but not straight again. The rotation tool steps too far with each adjustment to fix this.
image00005.jpg
Big fonts like where it says "MICROPROCESSOR SYSTEM DESIGN" result in uneven blacks. Cropping at the top is bad too.
image00010.jpg
More text at weird angles.
image00022.jpg
Crops in my arm which was using the cots again, and the photo looks really bad.
image00037.jpg
Wonky and a weird texture. This texturing problem happens on all pages with big diagrams.
image00060.jpg
This diagram is completely wrecked. The boxes at the top labelled D0 and D1 should be shaded grey, as well as several other boxes. Sometimes a bit of shading survives, but mostly it gets removed. At least it's not got that weird texture I guess.
image00081.jpg
Sometimes pages that don't even have diagrams get the weird textures.
Last edited by aestetix on 15 Aug 2022, 16:05, edited 2 times in total.
cday
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Re: Czur ET24 Pro first impressions

Post by cday »

Here's a detailed review I have found online: The gadgeteer - CZUR ET24 Pro Smart document scanner review, fast forward past the early sections for the more interesting content.

With respect to image processing, if necessary images from the double-page output option could possibly be better processed in a software such as ScanTailor.
aestetix
Posts: 26
Joined: 06 Sep 2021, 13:47
Number of books owned: 0
Country: United Kingdom

Re: Czur ET24 Pro first impressions

Post by aestetix »

Thanks cday. To be honest I think that the hardware is just bad. The system using the laser lines to fix non-flat pages just doesn't work. The pages that are flat come out okay, but once you get towards the middle of the book neither page will be flat.

Looking at what other people say, it seems like if they have fairly flat stuff to scan they think it's great. Stuff like magazines and ring bound catalogues come out fine, because the pages are fairly flat. Books end up with very distorted pages because of the way they are bound, and the Czur can't handle them.

Curious Marc said it was good for data books, but now I'm looking at his PDFs they do show some signs of these issues too. If you look at the example searchable PDF in the review you linked to, you can see that on page 2 some of the text failed to OCR and looks distorted.
aestetix
Posts: 26
Joined: 06 Sep 2021, 13:47
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Country: United Kingdom

Re: Czur ET24 Pro first impressions

Post by aestetix »

The software didn't crash today, so I scanned 300 pages. Of the 300 pages, about 5% were usable. The rest were either too bad to use or needed extensive manual adjustment.

Here are some more examples of how it is impossible to correct many pages. This sample page cannot be fixed with any of the settings in the software. The shading is always lost.
auto.jpg
bw1.jpg
bw2.jpg
bw3.jpg
color.jpg
grey.jpg
non.jpg
patterns1.jpg
patterns2.jpg
patterns3.jpg
stamps1.jpg
stamps2.jpg
stamps3.jpg
cday
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Country: UK

Re: Czur ET24 Pro first impressions

Post by cday »

A lot of images, screenshots evidently, but not too easy to deduce exactly what you expect or desire.

Are those images 'dewarped', or did they not need that?

If you edit your post and scroll down to the Attachments settings, there is an option to display text below each image, where you could add a comment on the image if you wish.

Are you able to simply capture a 24-bit image of a page, dewarped if that is necessary, and save that? If so, you would have the option to test your own corrections and might be able to get better results. And having found suitable corrections for one page, there should be a reasonable chance that they could be applied to a run of pages almost effortlessly using a batch conversion in an image editing software.

This recent thread illustrates what I an referring to, if that could be an option.
aestetix
Posts: 26
Joined: 06 Sep 2021, 13:47
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Country: United Kingdom

Re: Czur ET24 Pro first impressions

Post by aestetix »

The software de-warps it for you. The scanner shines three laser lines on the page and takes an image of them, to get the warping of the page. The problem is it doesn't work very well near the edges or near the spine.

There doesn't seem to be an option to save the raw, warped images. They are stored in some hidden place, and the only reference I found to it is out of date. It seems like they really don't want you to get access to them.

What I expect is a page that isn't warped, where the text is straight and the diagrams are readable. No weird yellow stains in the corners. Cropping that produces consistent page sizes (when you generate a PDF every page is a random size) and which crops out the edges of the book and the black mat under it.

The pages actually look a lot better if I run them through ScanTailor afterwards, but that software can't do de-warping. The fact that an open source tool does a far better job than their software is quite damning IMHO.

Oh, and the UI isn't DPI aware. It looks horrible and blocky. As does the PDF output. You can't change the window size either, it's always full screen.

It just doesn't do what it's supposed to do. Not fit for purpose.
cday
Posts: 451
Joined: 19 Mar 2013, 14:55
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Country: UK

Re: Czur ET24 Pro first impressions

Post by cday »

The Czur ET24 Pro is a new design, so possibly software updates will be released, but realistically the included software probably closely follows existing software, and so may be difficult to enhance. It is clearly a very demanding scanning application, but products should not be marketed unless they are capable of producing at least reasonable results. Probably best to return it quickly, if that is an option.

On a general point, originals that are pure black and white will generally be best scanned in black and white at the maximum available resolution, if the resulting image quality is acceptable. With suitable compression that will also result in much smaller file sizes.

Originals that contain no colour will generally be best scanned in grayscale, or converted to grayscale before further processing: that will avoid any colouration being introduced into the scans which cannot otherwise be easily removed. The grayscale images can then be enhanced using a 'levels' adjustment to as far as possibly remove any gray background. Halftone images such as photographs are in that category, as generally are images with areas of halftone shading, as in some of your posted images. While halftone images are, of course, composed of usually very small black dots, they normally can't be scanned successfully as black and white.

You may of course already know all that, and that a v-platen scanner, or when possible even better destructive scanning, is the best way to obtain high quality results!
aestetix
Posts: 26
Joined: 06 Sep 2021, 13:47
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Country: United Kingdom

Re: Czur ET24 Pro first impressions

Post by aestetix »

Thanks cday. I'm not sure I'd say this is a demanding scan though. Most of the images are from a fairly typical hardback book. One shade of grey is used, otherwise it's all black and white. Some of the pages are actually flat when being scanned too, so should be ideal as at most they will only need the lens distortion removing. Yet even they come out badly cropped and warped.
cday
Posts: 451
Joined: 19 Mar 2013, 14:55
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Country: UK

Re: Czur ET24 Pro first impressions

Post by cday »

Possibly you can rationalise that you need the space, and that any reasonably foreseeable future needs could be met with good quality scans?

Then you could seriously consider destructive scanning, ideally running the cut sheets through a scanner with a sheet feeder.

While I have fairly wide scanning experience, my only reasonably comparable experience was experimenting with scanning magazines by first removing the staples to separate the sheets, and then running the cut sheets through a high quality multi-function device in a public library. That did require devising an algorithm to crop the resulting scans into separate pages, and then renumber the resulting pages in the correct order. Some peace and quiet and coffee required! That step wouldn't of course be necessary for single cut pages from a book or magazine.

I finally scanned a batch of A5-size, fairly thin, club magazines that way for the club archive, obtaining good results.
aestetix
Posts: 26
Joined: 06 Sep 2021, 13:47
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Country: United Kingdom

Re: Czur ET24 Pro first impressions

Post by aestetix »

That's my plan I think. I did destructive before and the results were really good. I'll have to get a good HFS cutter (prices seem to have doubled in the last year) and a new sheet feed scanner though. My current one has developed a dead pixel, so you get a white line down every scan. For documents it's okay but for books...

I've been back and forth with Czur on email, and my conclusion is that it's simply impossible to get good results with this thing. Not what I would consider archival quality, at least. It's better than nothing, especially for books you can't destroy, but nothing of mine is that rare. The few things like that I do have I've already done in stages with a flatbed or using a camera, with results as good as this thing.
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