Building a simple 4x5 scanner back.

[KaJashey]

Not my build but I wanted to share this...

https://www.youtube.com/watch?v=sbNW4IHiXxU

It's very simple pretty easy.

[Robert Tilden]

Does he actually need the ground glass? I know almost nothing about the subject, but can't you scan the aerial image?

[KaJashey]

Does he actually need the ground glass? I know almost nothing about the subject, but can't you scan the aerial image?

Disclosure I'm one of the people thanked at the end of his video who made a similar camera. You need a diffuser and/or a fresnel. If you took an aerial image not much of the light goes straight in the scanner and it looks like this. Very small narrow not taking up much of the picture area. Using a really long focal length might help the ariel image but I'm not sure how much.

[Peter De Smidt]

Maybe try wax paper, diffuse mylar.....Would be great with an old Boss Screen, if they made one without lines.

Boss camera focusing screens where made with a layer of wax between two glass sheets. The texture of the screen was very fine, and yet the image was pretty bright. It might be possible to duplicate this using wax paper and an iron. When I was a kid, we'd gather colorful leaves in the fall, put them between two sheets of wax paper, with the wax side on the leaf, and iron both sides. This encased the leaf in wax. The same thing could be done to one side of the scanner glass, perhaps multiple times to get a thicker coating of wax.

[BKP]

Years ago I operated a Robertson 20 x24 copy camera. It was inverted, it had an "I" beam attached to the ceiling suspending the bellows, focus was achieve by the operator turning wheels inside the camera dark area, which were connected to the lens standard and the subject standard via cables and pulleys. Focussing was achieved by placing a sheet of diffuse acetate on the glass and viewing through with an 8x loupe, while turning the wheeled handle, once focus was achieved, all was locked down. Lens stopped down. Then in total darkness the receiving film up to 16x20 (limited by our film processers size) was punched with a film punch, then placed on the glass back which had pins cemented into it. The glass was not ground but clear. The glass back was hinged, closed and vacuum pump was started, all film boxes secured, copy lights on shutter actuated. The film was removed and processed.. Soooo. Since I do not have a 8x10 capable scanner or an enlarger set up yet. If someone were to place a scanner under an enlarger, which has been focussed. In theory one could bypass the print developing step. Has anyone tried this. I'm curious as to the results and exposure details. bk

[KaJashey]

...If someone were to place a scanner under an enlarger, which has been focussed. In theory one could bypass the print developing step. Has anyone tried this. I'm curious as to the results and exposure details. bk

Interesting idea. On some level it just adding an enlarger if the scanner can already do transparency.

[Drew Bedo]

This in fascinating , and sure its fun. . . .but.

hat does it get you ?

Resolution is bad. Exposures are Daguerreotype long. And the rig he is showing is $200 PLUS the amera. My TravelWide and lens total $300 for what I have in it . . .so $500..

Maybe if I could hang this on the back of my 4x5 for scout shots or to explore composition nd DOF before exposing a $7 to$10 sheet of Velvia . . .maybe that would be worth the effort and money. Anybody trying to make this into a LF back?

Great concept though. I'll bet improverments can be made.

[reddesert]

Is it practical? Not really. Is it clever and an entertaining idea? Yes. Image quality isn't everything.

The reason that he needs the ground glass surface, and that putting a scanner under an enlarger won't work well, is that the scanner has optics in it, which ordinarily focus the document onto the detector. The scanner lens receives light that comes straight-on (perpendicular to the bed). But the rays of light from a camera lens, or an enlarger lens with the scanner placed under it, are only straight-on when on-axis. Toward the corners of the frame, the light from the lens is incident at an angle, so it is vignetted by the scanner optics.

[Drew Bedo]

OK, I understand the liitations of this "hack" and the reasons.

Lets step away from the scanner-as-camera concept for a moment and look at something related. How well does this item handle a 4x5 transparency? Can I scan them from a light box with this thing . . .or something similar? Is there a more sophisticated (expensive) piece of gear that is just as handy?

I typically work with a Epson V750. Results are great, but its a beast.

[Tom Monego]

I went to research a BetterLight scanning back, 20 year old technology but prices haven't budged or gotten more expensive. Not 4x5 but better resolution than this thing. All I can see is it has funk appeal.