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Hi in this video I'll show you how my scanner camera works, and the procedure to take photos
I'm using an EPSON V30 flatbed scanner
modified for this purpose
the CCD sensor is mounted on the sliding part of the scanner
instead of behind all the mirror and lenses
so the image is projected on the sensor from the large format lenses
mounted in front of the scanner
The lens is an "Industar-37", 300mm f4.5
The electronics of the scanner requires a calibration phase at the beginning of every scan
depend on how much light the CCD receive, the processor adjusts the gain for the signal
so I mounted a LED light in front of the sensor, and using a dimmer I'm able to adjust the sensitivity of the scanner
because of my modify, the scanner now use only the real height of the sensor
which does not cover the entire height of the scanner, but it's only about 5 cm
but the computer doesn't know about my modify, so the resulting image is compressed horizontally with 5:1 ratio
Also because of my modify, now the RGB channels are shifted horizontally from one to another
To take a photo, the first thing is to have the camera in focus on the subject
this procedure can take from 2 to 10 minutes, taking a lot of preview scans and zoom scans
and moving the lens with little steps
the lens cover without problems all the scanner surface
but for this video I'm scanning only a part of the image
because I'm interested only in the part where is the window
when the scanner is in focus, I choose the resolution: in this case 720 DPI
now I click "scan" and wait for the picture..
Most of the time I scan at 600 or 1200 DPI, and now, at 720DPI it takes about 70 second
for a full scan at 1200 DPI 48bit it takes about two minutes
after that, the image must be resized, but because it's really huge I prefer to change only the pixel aspect ratio
so I can work on the channels and levels on a less heavy image, and at the end I resize it
aligning the channels is really simple and it take about a couple of minutes
after that most of the time I have to correct the levels
because the sensitivity of the sensor is pretty low, and if I want some depth of field
with not too much noise, the image is always dark, but it's not a problem
because at 48 bit I can tweak the levels without banding or other issues on the dynamic range.
now as I said, I'm changing the aspect ratio...
now it's time to align the channels together...
red...
...and blue.
Now it's time for the levels, just to for matching the color balance and cover all the original dynamic range
Now the process is complete and remains only to resize it properly
this camera allows to shift the scanner vertically and take multiple pictures without moving the lens
using this feature I can cover a large part of the lens projection, and merge the pictures in Photoshop.
By the way, depending on the DPI and by how many scans I merge together
this camera can make images from few hundreds of megapixels to about 4 gigapixels
but I haven't done anything over 2 gigapixels
I hope you enjoyed this video, and if you want to see more about this project
just click on the button for my gallery with all the photos and information
and if you have some questions, don't be afraid to ask!
(the song was: "One Of These Days I'll Get An Early Night" by Camel)
goodbye!