Mirrorless DSLR for bookscanning

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

Moderator: peterZ

rajbot
Posts: 7
Joined: 04 Mar 2014, 00:53

Mirrorless DSLR for bookscanning

Post by rajbot »

Hi,

If anyone is currently using DSLRs for book scanning, I wanted to drop a note about some research I've been doing on mirrorless DSLR cameras.

The Internet Archive currently uses Canon DSLRs for its book scanners. On cameras such as the Canon 5D mk3, which let you lock the DSLR mirror and have a silent mode, camera failure is still a constant issue (at around 100K shots IIRC).

I've been investigating the Nikon 1 J3, which is a consumer-grade mirrorless DSLR camera that costs ~$400 with a kit lens. This camera has no mirror and also has an electronic shutter, which makes it quite robust. I've shot more than a million shots(!) on a Nikon J3 and the camera is still operating well.

I worked on the gphoto driver for this camera and added support for the J3 and the other Nikon 1-series cameras to gphoto. This work has been pushed upstream, and is now available in gphoto 2.5.5. http://gphoto.org/news/

I'm excited about checking out the next generation of mirrorless DSLRs, and am interested in reports if anyone else is going this route..

-raj
vitorio
Posts: 138
Joined: 30 Oct 2010, 23:56
Number of books owned: 0
Location: Austin, Texas, USA
Contact:

Re: Mirrorless DSLR for bookscanning

Post by vitorio »

rajbot wrote:I've been investigating the Nikon 1 J3, which is a consumer-grade mirrorless DSLR camera that costs ~$400 with a kit lens. This camera has no mirror and also has an electronic shutter, which makes it quite robust. I've shot more than a million shots(!) on a Nikon J3 and the camera is still operating well.
Sorry, I don't know enough about camera internals to know if these are dumb questions or not, but is the big deal here the mirrorlessness, or the electronic shutter?

It doesn't look like a lot of mirrorless cameras also have fully electronic shutters, maybe just this one and a Panasonic model?

Are there non-mirrorless cameras that have electronic shutters, or are the mirrors also a point of failure?
duerig
Posts: 388
Joined: 01 Jun 2014, 17:04
Number of books owned: 1000
Country: United States of America

Re: Mirrorless DSLR for bookscanning

Post by duerig »

Vitorio, I know just enough to be dangerous. :-) The pieces which are mechanical are where the failure due to wear and tear will come from. On a normal DLSR, the mirror lets you use the viewfinder and it is moved out of the way to take the actual picture. The mechanical bit that moves the mirror out of the way is going to have a lot of wear and tear.

Based on a back-of-the-envelope calculation, 100k shots gives you at most 500 books per camera. Half that if you are taking separate shots of the two pages. That is a depressingly small number. I like the 1 million and counting number much better. If and when my cameras break, I will look to replace them with the Nikon 1 J3 or its successors.

Thanks, rajbot, for pushing the control software for it up to gphoto2!
Ralf
Posts: 6
Joined: 17 Jul 2012, 18:16
E-book readers owned: Kindle, iPad
Number of books owned: 5000
Country: Austria

Re: Mirrorless DSLR for bookscanning

Post by Ralf »

Sounds very interesting, Raj.
How can the Nikon 1 J3 be triggered remotely?
rajbot
Posts: 7
Joined: 04 Mar 2014, 00:53

Re: Mirrorless DSLR for bookscanning

Post by rajbot »

Hi,

The J3 can be triggered remotely when connected via USB using the gphoto software. You can capture to either memory card or internal SDRAM. The command for capture is

Code: Select all

gphoto2 --capture-image-and-download --filename image.jpg
If you have multiple cameras connected via usb, you can specify which camera to trigger using the --port option.
User avatar
jbaiter
Posts: 98
Joined: 17 Jun 2013, 16:42
E-book readers owned: 2
Number of books owned: 0
Country: Germany
Location: Munich, Germany
Contact:

Re: Mirrorless DSLR for bookscanning

Post by jbaiter »

Slightly off-topic, but spreads can be used for shooting as well, there is a gphoto2 driver available (that I revamped this week) that uses libgphoto2 under the hood.
spreads: Command-line workflow assistant
rajbot
Posts: 7
Joined: 04 Mar 2014, 00:53

Re: Mirrorless DSLR for bookscanning

Post by rajbot »

Support for the Nikon J4 has been now added to gphoto. The J4 is an 18.4-megapixel update to the J3.
bgalbrecht1
Posts: 4
Joined: 29 Nov 2014, 19:06
E-book readers owned: nook
Number of books owned: 0
Country: usa

Re: Mirrorless DSLR for bookscanning

Post by bgalbrecht1 »

The Nikon 1 J4 has been discontinued, but I found a couple new locally for $350 each. Is anyone using either the J3 or J4 for scanning now? Are you using jpg or raw for your images? When I was scanning with my Opticbook 3600, I normally scanned with png images because they are lossless.
bgalbrecht1
Posts: 4
Joined: 29 Nov 2014, 19:06
E-book readers owned: nook
Number of books owned: 0
Country: usa

Re: Mirrorless DSLR for bookscanning

Post by bgalbrecht1 »

Another mirrorless camera I'm looking into is the Sony Alpha A3000, which also appears to be supported by gphoto2. It's also about $350 locally. Has anyone tried it?
ossi5110at
Posts: 5
Joined: 09 Apr 2014, 05:04
E-book readers owned: ipad
Number of books owned: 200
Country: Austria

Re: Mirrorless DSLR for bookscanning

Post by ossi5110at »

hi,

i am currently using 2 Nikon d3300 with the bulk objective. triggering them with http://digicamcontrol.com via usb. scanned roughly 20000 pages so far without errors. for color correction I use Adobe Lightroom. OCR with Abby and/or Acrobat. I have chosen the d3300 because of 24mp resolution and the manual focus of the dslr which gives me a fast adjusting to book pages.

workflow:
1. take pictures
2. copy to pc in 2 separate folders ( left and right labeled) because I figured out that the file names mess up a bit with cam control sw so I use camera files.
3. Lightroom work (color correction, vignettes, cropping, turning pages - export in 2 folders)
4. renaming using rename.exe so I get files in left folder xxxx002.jpg, xxxx004.jpg and so on for left folder. renaming right folder with ending 1, 3, 5....
5. combining them in acrobat. checking page numbers to see if I didn't mess up something.
6. Important now is to safe file before OCR because sometimes pc hooks up and also I can decide now to continue either with acrobat or Abby.

I also checked for industrial cams, but setup total would have cost to much.

usually I scan between 700-1100 pages per hour, but rest of this workflow is more time consuming.

kind regards from Austria
Ossi5110at
xxxxxxxxxxxxxxxxxxxxxxxx
... experimenting with Nikon D3000 atm.
Post Reply