Do we actually need portable cameras ?

Everything camera related. Includes triggers, batteries, power supplies, flatbeds and sheet-feeding scanners, too.

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jgreely

Re: Do we actually need portable cameras ?

Post by jgreely »

CCDeye wrote:Actually I only need true 2 MP photos for my needs. I can't believe, there's no web cam that can deliver this.
If the manufacturers thought customers actually cared about the still photo quality of a webcam, they'd fill their web sites with samples, and provide clear specs to convince people to buy theirs instead of someone else's. Instead, they bury the details and quote phony interpolated megapixels, which means the marketing department is just painting racing stripes on a Geo Metro. I don't see this changing; if the high-end ones are going to 5MP, it's so they can do digital pan and zoom of video, not high-quality stills. Cellphone camera sensors are more likely to become useful for book-scanning, since people actually use them for stills.
Well, I can try to disassemble an old photo camera(not even digital) and put the web camera sensor where the tape is, behind the lens. Then focus manually etc.I don't know if the sensor matrix size of the web camera is too small for the objective to project cover the entire picture.
This sounds painful. Any film lens will have more than enough coverage for the sensor, but the focal length would have to be pretty short to be useful (~14mm, assuming a 1/3.2" sensor), and you'd need very precise positioning to get it to focus properly. Adding a close-up lens to a webcam would be a lot easier; if the problem is actually focus, a magnifying glass or old pair of reading glasses will tell you if the sensor can actually take a decent close-up still. More likely, the sensor is too noisy and low-contrast to deliver what you want.

Handwaving the numbers suggests that a +3 diopter close-up lens should bring the focus point in enough to fill the frame with a book. (that is, given a webcam with sensor width W and focal length F1 (both in millimeters) focused at infinity, adding a closeup lens with diopter D gives F2 = 1000/(1000/F1 + D), M = F2/(F1-F2), for an in-focus object size of W * M; the closer the original lens focuses, the less diopters you'll need to add)

-j
CCDeye
Posts: 17
Joined: 20 Apr 2011, 12:28

Re: Do we actually need portable cameras ?

Post by CCDeye »

jgreely wrote:
CCDeye wrote:Actually I only need true 2 MP photos for my needs. I can't believe, there's no web cam that can deliver this.
If the manufacturers thought customers actually cared about the still photo quality of a webcam, they'd fill their web sites with samples, and provide clear specs to convince people to buy theirs instead of someone else's. Instead, they bury the details and quote phony interpolated megapixels, which means the marketing department is just painting racing stripes on a Geo Metro. I don't see this changing; if the high-end ones are going to 5MP, it's so they can do digital pan and zoom of video, not high-quality stills. Cellphone camera sensors are more likely to become useful for book-scanning, since people actually use them for stills.
Actually, the camera is garbage, it's not the focus :|
As for the cellphone cameras, for example SonyEricsson Satio shoots very nice still photos with 12 MP.
Pantagruel
Posts: 24
Joined: 06 Jul 2010, 19:40

Re: Do we actually need portable cameras ?

Post by Pantagruel »

I experimented last year with Logitech QuickCam Pro 9000s (you can find my posts and others' comments somewhere in the Forum by using the search function and looking for "Logitech QuickCam Pro 9000"). You can focus them manually by using the software, but I wasn't able to get a stereo setup to work without going to two separate computers. A USB switch slowed things down too much, so I ruled that out as well. However, the 2 megapixel results were fine for my purposes, since I didn't need to go beyond a 9" or 10" x 5.5 or 7" format. The setup is a bit tricky; for one thing, they have to be rather close to the target, and the lighting has to be carefully aligned at that close distance to avoid shadows from the camera itself, but it is do-able. I haven't yet acquired one of the new Logitech 5 mexapixel cameras to see how well one of them might work. I ended up constructing a book digitizer using one Pro 9000 and and a rather compact box with the glass at one edge, somewhat along the lines of the Plustek OpticBook 3600 Flatbed Scanner, and flipping the book for each page (so that the odd numbered pages were upright and the even numbered were rotated 180 degrees. Scan Tailor took care of the rotation. The results were quite readable, but then I don't use OCR because the original formatting and page numbers are important to me for scholarly citations. Also I did not intend the setup to be usable for larger format books. So far it has worked well for us.
CCDeye
Posts: 17
Joined: 20 Apr 2011, 12:28

Re: Do we actually need portable cameras ?

Post by CCDeye »

Thanks, I see this webcam could be of some use..
How fast it captures a 2 Mpx shot on a reasonable powerful PC with USB 2.0 ?
If only those Logitech cams were cheaper. I can get a 12 Mpx Canon for that price. Can you post a comparision shots of a same book page with this web cam and a point and shoot camera that is setup for 2 mpx ? I have a feeling it's not only the megapixels that matter.
Pantagruel
Posts: 24
Joined: 06 Jul 2010, 19:40

Re: Do we actually need portable cameras ?

Post by Pantagruel »

I just bought a Logitech C910. When I can get back to my computer at home, I'll post a trio of pictures consisting of a straight shot of a page, the ScanTailor-processed TIFF file, and the OCR version using Abby FineReader 5.0. The C910 can do a true 5 megapixel image, non-interpolated, and I found one online, "like new" for $54, which is the one I employed for making these rather casually-taken images. The point is that even the Quickcam pro 9000 will work with OCR if you're not copying a page larger than about 6" x9" or so, or a larger page that uses a bigger font size in my experience. You might be able to find a 9000 used online. They're fairly robust units; I've never bought one new.
Pantagruel
Posts: 24
Joined: 06 Jul 2010, 19:40

Re: Do we actually need portable cameras ?

Post by Pantagruel »

Here are two sets of images and text files. Those marked Kaiser were done with a Logitech QuickCam Pro 9000 (2 megapixels); those marked Beaujour were done with a Logitech C910 (5 megapixels). If I had kept the same text for both, the comparison would have been more useful, but they were done at different times. I chose deliberately not to line them up too precisely, so there is some keystoning and warping. As you can see, ScanTailor had no problem with them. I used ABBY FineReader 5.0 lite for OCR.
The text is from the back of the jacket of each book (to avoid any copyright problems, since this is not actually part of the content of the book). The OCR program made three errors on the Kaiser dust-jacket text; it made only one on the Beaujour, and that was because of a bit of extra ink that intersected one letter, so I would say that it was practically one-hundred percent accurate.
The Kaiser (hardback) was about 5.75" x 9"; the Beaujour cover (paperback) measured 5.5" x 8.5". As you can see, the type for the Kaiser jacket description is in red.
Sorry the order got a bit scrambled in posting.
Attachments
Kaiser after processing with ScanTailor
Kaiser after processing with ScanTailor
Beaujour after processing with ScanTailor
Beaujour after processing with ScanTailor
Beaujour original image
Beaujour original image
BeaujourOCR'd.rtf
Beaujour OCR text file (ABBY FineReader 5.0)
(5.43 KiB) Downloaded 477 times
KaiserOCR'd.rtf
Kaiser OCR text (ABBY FineReader 5.0)
(3.16 KiB) Downloaded 483 times
Kaiser original image
Kaiser original image
the.traveller
Posts: 82
Joined: 22 Sep 2010, 03:58
E-book readers owned: Samsung Tab S
Number of books owned: 800
Country: Netherlands
Location: Rotterdam, Netherlands

Re: Do we actually need portable cameras ?

Post by the.traveller »

CCDeye wrote:Actually, the camera is garbage, it's not the focus :|
As for the cellphone cameras, for example SonyEricsson Satio shoots very nice still photos with 12 MP.
I totally agree with you , I own a Satio, however since there is no mounting hole to put it on a tripod or something like that it's a total drag to get pictures of a book. It makes great overall pictures but just not for the purpose we are here on this forum.

The essence of what I mean is that when I take pictures I each time have to refocus and position the book in the center of the screen to get the same lay-out. Because of the inconsistency it is hard to process the pictures quickly with the preferred software. (Scantailor??)
Also if you get to close to the book, the flash of the camera makes a total wash out on shiny surfaces. If you take a too long distance to the book for preventing the flash to be seen you have to zoom in so much that it will give minute distortions.
Also I can't get my Satio camera at the same horizontal plane as the book giving distortion.
I even tried it in the light of the sun coming in. But it will do the same as the flashlight. The part where the sun hits first will wash out and the part from the page which isn't hit first is more darker. I agree that it is a gradual effect but it is visible.
Putting a large white sheet of paper in the sun's rays also didn't help. The same gradation of the sun, although less, is still visible.

Believe me I have tried all.

The main objection is, that you have to hold the camera in your hand and that there is no possibility to mount the camera without damaging the Satio. And secondary, as far as I know, there is no connection possible to have it triggered repeatedly without moving the camera from it's place.

I challenge all the Satio owners, who actually have a solution without loosing it's original function - the phone, to prove me wrong.

http://imageshack.us/g/27/20092010468.jpg/
http://imageshack.us/photo/my-images/80 ... 10457.jpg/
the.traveller
Posts: 82
Joined: 22 Sep 2010, 03:58
E-book readers owned: Samsung Tab S
Number of books owned: 800
Country: Netherlands
Location: Rotterdam, Netherlands

Re: Do we actually need portable cameras ?

Post by the.traveller »

Update: I myself have to swallow my words. :shock:

I have found something which enables you to take pictures with your phonecamera (i.e. Sony Satio) from a tripod.
It is called in an advertisement in my country a Walimex with tableclamp, and is for sale for a mere € 2,50 without sending cost.
http://imageshack.us/photo/my-images/69 ... ard67.jpg/

The page where I found it is:
http://audio-tv-foto.marktplaats.nl/fot ... lklem.html?

Since this is an advertisement which could disappear when the seller is sold out, the actual page I took a photo from and is to be seen on imageshack. (I don't know how long those pictures are kept)
DSpider

Re: Do we actually need portable cameras ?

Post by DSpider »

I completely agree. Why isn't there an (affordable) way to buy just the sensor+lenses inside a generic plastic casing? I don't need an LCD screen, microphone, internal memory and some bullshit software.

Basically a web cam. Completely powered by USB.

I was thinking maybe from an RC (radio control) store for hobbyists? But they probably won't have anything higher than 1.3 MP...

Image
http://en.store.creative.com/web-camera ... 20165.aspx

What do you make of this one? It's in the C910 price range and they say it's 12 MP (software enhanced, but only with their software, apparently). Says it works on Linux too - except for the software that can enhance it to 12 MP, which is Windows-only from what I can see.

My only concern is that one of the Newegg reviewers said that the autofocus made some noises. What do you think? Does it have a servo mechanism? Photos look very different from the rendering:

http://images17.newegg.com/is/image/new ... Z02?$S640W$
http://images17.newegg.com/is/image/new ... Z01?$S640W$

Hmm... You know what, I'll just send them an email inquiring about it and about what megapixel count I can expect if I'm not using Windows (tho I could use VirtualBox and a lighter, custom version of Windows XP just for the damn "enhancing" software). They'll probably get back to me next week, since it's the weekend and all...

I'm interested in hearing some more feedback, if you have any. Thanks.
Last edited by DSpider on 29 Aug 2011, 15:44, edited 2 times in total.
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Misty
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Re: Do we actually need portable cameras ?

Post by Misty »

"Software enhanced" just means that they interpolate the image. It's not true detail. The specifications note that it only captures 1920x1080 - about 2 megapixels. That's plenty good enough for a webcam, just not good enough for us.

Which is the problem! There hasn't been a huge market for webcam-style cameras with higher than HD resolutions (obviously some exist, since people are talking about them in this thread), just because people haven't been using the cameras to do stuff like this. Economies of scale, unfortunately.
The opinions expressed in this post are my own and do not necessarily represent those of the Canadian Museum for Human Rights.
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