DSLR Scanner: Negative Stages

[Peter J. De Smidt]

DIYS (Do It Yourself Scanner—pronounced like ‘dice’)--Negative Stages Thread

Frank Pertronio started this project by suggesting that someone come up with an affordable and contemporary drum scanner, as there is currently huge gap in price and quality between consumer and professional scanners. Domaz suggested using APS-C sensors and using them to take samples of the film, similar to what Gigapan does with large stitched mosaic images. This lead to talk about making a copy stand scanning system using a dslr, a light source and a movable negative stage. Both horizontal and vertical prototypes have been made, or are in the process of being made.

The original thread (http://www.largeformatphotography.info/forum/showthread.php?84769-Making-a-scanner-with-a-DSLR) has become very long and unwieldy. As a result, I’m creating some new specialized threads for future project development.

The new build threads are:
Camera Supports and Positioning (http://www.largeformatphotography.info/forum/newthread.php?do=newthread&f=7),
Lenses (http://www.largeformatphotography.info/forum/newthread.php?do=newthread&f=7),
Negative Stages (http://www.largeformatphotography.info/forum/newthread.php?do=newthread&f=7),
Light Sources (http://www.largeformatphotography.info/forum/showthread.php?87536-DSLR-Scanner-Light-Sources),
Stitching and Blending of Images (http://www.largeformatphotography.info/forum/newthread.php?do=newthread&f=7),
Cameras and Camera Control Software (http://www.largeformatphotography.info/forum/newthread.php?do=newthread&f=7).
Workflow (http://www.largeformatphotography.info/forum/newthread.php?do=newthread&f=7).


These threads are only for positive contributions to the development in the area in question. The project may not succeed, but we’re going to find that out by trying it. But we are not unkind. As the original thread showed, some people have an overpowering urge to say negative things about the project. I’ve created a thread just for this purpose. Please post your negative comments about the project here (http://www.largeformatphotography.info/forum/newthread.php?do=newthread&f=17).

I would like to thank everyone who makes, or has made, a positive contribution to this project!

I'll be summarizing the posts from the original thread about negative stages here soon.

[Nathan Potter]

http://farm8.staticflickr.com/7196/6894463471_bfaf591921_z.jpg (http://www.flickr.com/photos/argiolus/6894463471/)
DSLRstage-1jpg (http://www.flickr.com/photos/argiolus/6894463471/) by hypolimnas (http://www.flickr.com/people/argiolus/), on Flickr

I think that I am convincing myself that using a DSLR as a scanner can produce some really superior scans. I won't actually try this out until I have a full frame DSLR in April but have been looking at "junk" parts on hand and some relatively inexpensive stuff that I can buy.

So attached above is a sketch of a possible X/Y film moving stage (horizontal mount version) that would use a couple of rack and pinion X and Y movements from Edmund Scientific (Edmund C59-333, page 238 current optics cat.). These racks travel the amount required for covering 4X5 film. Resolution maybe about 100 um. The sketch is a design akin to ones I have used in the past. In the front view, at the bottom one will see a fixed sliding base upon which a moveable platen with leveling screws slides carrying a glass film mount with it. The leveling screws are assumed to be plastic for ease of sliding. The film aperture in the X/Y film holder is of course 4X5. The pressure spring supplies downward force on the film mount and is rigidily attached to the Y axis rack and pinion at the right of the sketch. Whole assemply is maybe 14 X 14 inches square.

Any how probably one of many approaches.

Nate Potter, Austin TX.

[Peter J. De Smidt]

Looks great, Nathan!

[marfa boomboom tx]

a link from other folks interested in making digital copy negs... these are expensive. the samples show the tango still king.

http://forum.getdpi.com/forum/medium-format-systems-digital-backs/38097-negatives-witha-digital-back.html

but do notice how simple the light and holder are...

[Peter J. De Smidt]

Here's their brochure: http://www.digitaltransitions.com/pdf/RGC180DS.pdf

They're not doing any stitching, though.

[polyglot]

If you're in Adelaide, someone is selling this (http://www.evansclarke.com.au/detail.asp?id=429571) old CZJ X-Y table for $50. It'd be incredibly accurate, just a little... large. Good if you want to digitise 16x20 though ;)