Re: Original ~600pg/hr, very portable scanner now achieving ~900pg-1100pg/hr
Posted: 30 Mar 2017, 14:50
None taken. All ideas welcome, and that's a nice scanner and does an excellent job.
The objective the builder had for the design was to handle text very close to the book's spine and for that, our imaging methods are the same (mine vertical, their's angled) and so we get the same results as my scanner meets that key objective the designer had.
As far as meeting my objectives, here's why that scanner doesn't work for me (though may be fine for others):
That is relative to your skill set and tool box. It may be "dirt simple" to build for some with the skills, tools and space to build it, but even if "dirt simple", it does require a lot, lot more construction than mine (which requires all of drilling 6 holes and making 5 cuts of plastic pipe and 1 of threaded rod -- no painting, accurate wood work, etc.) and even this some find too much!
Also that scanner will require some good wood working skills and tools (the builder mentioned at one point: "I used a table saw for the 3 sided frame surrounding the glass") and as well as accurate work to make sure the platen square with the camera so there are no key-stoning effects. By comparison I use a ball joint and the iPhone's levelling tool (second panel of the compass app) to make sure the camera is square with the table (or rather I place the phone on the table to see its tilt (if any) and then match that after mounting the phone to the support; just takes a minute to get done).
Yes that's probably true, but at around $80ish for mine, it's not going to break the bank. And besides, the Manfrotto clamp can be used for general picture taking if you don't want to lug a tripod around.
I would have to disagree with you there. It doesn't look like it knocks down, but even if it does, it's got some very large parts, and looks like it weighs quite a bit. I really would not want to walk into a library and set that up.
For comparison, here's my scanner dismantled and packed for transport. Assembly requires attaching the handle to the platen (wrapped in the white towel) (2 bolts needed) and attaching the horizontal post to the vertical post (1 thumb nut needed).
That is true, but the image size problem is not a "real problem" but more an aesthetic one. The difference in size is only about 5% for 230 page book (see viewtopic.php?f=14&t=3007#p17556) and easily solved with the macro focus bar to the point it requires a 2 second adjustment every 40 pages to virtually eliminate.
However, the last commenter (MJM) in the thread makes some very important points (viewtopic.php?f=14&t=2549&start=10#p19577). In particular, he/she mentioned:
One of my design considerations, was to be able to scan paperbacks without cracking or damaging the spine (and even trickier if the text is close to the spine). As you'll see with the the scanner you suggested, books are opened well beyond 90 degrees (it looks like 135 degrees) to scan and that will almost certainly damage the spine, as the commenter noted also.With it you can get more text when the text is too close to the gutter, but the tricky part of it is scanning without harming the book, and most of them will be if they're opened more than 90º. In any case, one key is to get the pages to be flatten from the book spine itself, so flattening the text with a glass is not enough, you must get the entire book in a position where the pages block is not turned or curled at any point. You make this at the same moment you choose the angle of scanning. Its the way to do it specially if you want to OCR the text lated, in order to avoid distorsions.
By comparison, with mine you don't need to open books much more than if you were reading the book. See the schematic I posted earlier in this thread. Notice the book is not bent back beyond 90 degrees and it can be reduced to perhaps 75 degrees as long as it clears the field of view (FOV) as shown by the diagonal lines from iPhone holder to the left and right edges of the book. If you drop the camera on the macro rail the field of view allows you to "look deeper" into the spine so even books that curl a lot are less of a problem and the curl does not block the page being scanned.
Furthermore, since you're not having to support the weight of the book (see below) you can effortlessly control the book to ensure the spine is not damaged. I've scanned many paperback books without creating so much as a crease in the spine as the book was never opened much more than you would for reading and I think if I had the bevel on the left edge of the platen, I mentioned earlier and shown in the schematic, things would be even better.
Besides this problem, the other real problem (for me) with the design you suggested is its operation: it will be slower, less efficient and more tiring to use because of step 4 (steps 1, 2, 3 and 5 are the same as my scanner):
1) You have to lift the platen with say your right hand (and lets assume you even have a convenient handle and shutter trigger attached to it -- which it doesn't so more construction).
2) You have to turn the page.
3) Drop the platen back.
4) But now, instead of just taking the image (as with mine), you have to lift **and** press the entire book with your left hand against the platen to flatten the page, and some times press quite hard depending on the binding and especially so to get text close to the spine. As the scanning progresses, the book will get heavier and heaver as more pages fall to the left side, and it will get more tiring to press. Also the scanner itself will have to be heavy or clamped down to the table so the it doesn't end up sliding on the table if you have a book with a spine that requires a lot of pressure to flatten the page close to the spine.
By comparison, with mine, there is no extra tiring step to lift and press the book flat against the platen, instead when you drop the platen back (step 3) you just put a little downward pressure on it (rather than lifting the book) to flatten the page -- if more pressure is needed for some spines, it's not tiring as the platen handle actually acts like a lever to amplify the pressure down and so just a little more pressure (and that is downwards not upwards) is all that is needed.
Essentially, since my design uses the table as part of the scanner, it has less parts and construction and since it uses gravity to assist you, rather than work against you, it's less tiring and more efficient to use.
5) Take the image. However, since there is no dark background behind the book (as there is with mine, between the book and the table) you'll probably have to tape a large dark card to the front cover of the book (and then the back cover) and worry about it.