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sergiob
19-Jan-2013, 16:23
I took the enlarger head of my Leitz valoy enlarger, adapted an L bracket made from stainless steel that I can fix to the screws that supported the head on the pistol grip and mount my Pentax 645D with the very impressive Pentax 120 f4 A macro lens with an extension ring.
I made a box, covered the bottom with white led strips put two acrylic diffusers separated by a couple cms each and a glass on top covering the box. On top of the glass I placed a 4" diameter pvc pipe cut to about 2-3 cms length. On top of the pipe I place my film holders from my beseler 23c enlarger. The box has 3 screws mounted on the 3 of the sides that let me level the box with high precision to have both film plane and sensor plane as parallel as possible.
The image quality I am getting from "scanning" or duping my negs is way better than what I get from any epson scanner. Focus is perfect. the system really goes into the film grain. Very low noise captures vs the epson scans. I am stitching panoramic 35mm negs shot with a widelux in two shots with great success. It seams perfectly. And best of all it takes about 20 mins to scan a full 36 frame roll. Slides are pretty easy to scan too because the leds are a reasonable white to balance in Lightroom. Color negs as always are a big pain. I'll try to post some pics of the setup if someone wants to give it a try. I suspect manual movement of a bigger format neg under the camera to capture in several shots to later stitch should not prove too difficult to do. My 2 cents for this great forum that has given me so much.

Ken Lee
19-Jan-2013, 17:41
I'd like to see some images.

adelorenzo
19-Jan-2013, 20:42
I'm working on something similar (with a much more modest digital camera) and would also love to see pics of your setup.

Peter De Smidt
19-Jan-2013, 20:50
Yes, this is a very viable technique. A couple of us have been working on this, in it's stitching variant, for quite awhile. We've had manual systems working for over a year, and we're very close to having an automated system of negative movement and image capture, using stepper motors, an Arduino and stepper drivers. You can see the threads on the DIY forum here, under the DSLR Scanner threads. They got so unwieldy that we split the original thread off into component threads.

sergiob
20-Jan-2013, 07:52
Yes, I read all the threads, but it is way too complicated for me to do in a high tech fashion. I lack the time, the skills, the tools and the energy for such involved projects. If I am able to stitch successfully 4 frames out of a 4x5 neg by moving it manually with some sort of guide, I'd very pleased. I made my box big enough to accomodate 8x10 film, but if that is too difficult to stitch, I'll stick to 8x10 contact prints, which are in my opinion is one of photography's most beautiful manifestations.

Since I process my B&W with great care and in an archival manner, I'm not worried for their permanence. I do worry for the hard drives longevity though, but thats another story. What I did find very useful is in my slide archive. Images shots about 20 years ago are already starting to show color shifts and degradation. Here is where having a simple, efficient and fast enough process as this one outlined here, comes in very handy. Scanning 5,000 slides in a flatbed is something I won't be doing. I'd rather be outside shooting new stuff.

sergiob
22-Feb-2013, 18:09
89983899848998589986 Here are some images of the setup. For some reason they upload rotated, but I hope you'll get the idea. The led strips are very convenient and very easy to solder. They come as an adhesive tape in 5m rolls. You just cut them and stick them to bottom of the box, and solder them. 2 cms. above the leds I put a white piece of white translucent acrylic as a diffuser. Then at the top I put a second piece of the same acrylic to get a very even white surface. On top of that I put a piece of 2mm regular framing glass with no imperfections to protect the acrylic diffuser of scratches. On top of this I put a piece 3 or 4 in. PVC pipe, on top of which I lay my film holder. I put a level on the camera and then on the film holder and level the box with the 3 screws. It is way easier to level a box with 3 screws than with 4. 2 on the back sides and one in the middle of the fromt side. Big flat 4x5 or 8x10 negs are very easy to copy just over the glass with no holder. I can copy a full 36 exposure 35mm roll in 20 mins. My macro lens is very sharp and it definitely goes way in into the grain of TX400. And no noise in the highlights (the dense dark part of the negative) as I was experiencing with my Epson scanner. I've done a couple of quick 2 frame stitches of one negative and they were very straight forward to do. My color slides copy need very little WB adjustment. The LED source has a good color temp to do that too.

Daniel Moore
1-Mar-2013, 12:40
I'm curious what shutter speed and aperture you're getting with that light source.

sergiob
2-Mar-2013, 09:48
At f11, which is very good with this lens and has a little more DoF, at 1/2 - 1/8. It works beautifully. It really goes way into TX grain. The results are way better than what I get with and Epson flatbed. It provides a very convenient workflow. You "scan" a roll in about 20 minutes, put in Lightroom and start organizing and editing right away. Even if you plan to enlarge the negs on paper, it is still a good idea, because there are some many great shots you miss because 35mm contacts are too difficult to edit well. The 3 screw thing is very easy and precise to align sensor and film plane. I was copying some 4x5 negs sandwiched between an antinewton glass and a regular framing glass emulsion side up towards the lens and it is very easy to do, and it allows for easy positioning for manual stitching. They couldn't be flatter. I still have to try it with 8x10, but that will have to be stitched because I can't raise the camera enough to use this lens and cover the full format.

Peter De Smidt
2-Mar-2013, 10:14
Thanks for the info, Sergio. What iso sensitivity is the camera set to with that f-stop and shutter speeds?

SergeiR
2-Mar-2013, 21:37
Basically same as if you just drop large acrylic semitransparent cutting board on top of already diffused source (soft box or dish) , throw flash behind it.. tape film on board, stick camera on tripod make sure both edges are in focus and shoot away with decent lens.. May even make LCC profile to get rid of unevenness in illumination prior to that. Cheaper, less work. Kinda reverse concept to Leafscans (they use projection shooting, afaik).

Of course you still limited by resolution of your final receiver, but for quick and dirty this is indeed good solution. Can even use panorama head to get stitching to deliver more resolution, of course still need some serious macro lenses to go with it but hey ;)

Daniel Moore
2-Mar-2013, 21:44
I think Peter was asking specifically what ISO you're using, the thing I forgot to ask. You're certainly in the danger zone and getting very good results, that's reassuring.