Moveable Large Format back for DSLR

[Joseph O'Neil]

Has anyone actually ever used one of these things?

http://cgi.ebay.com/Moveable-Large-Format-back-4x5-camera-Nikon-Sinar-/330509027022?pt=AU_FILM_CAMERAS&hash=item4cf3df86ce

This is the Nikon version, they have others as well such as Canon. I suspect regardless of brand of DSLR, they all work the same. The only reviews I seem to find on the net are you need to use at least a 135mm to 150mm lens otherwise you are compressing your bellows too much.

I've uploaded a photograph too. Looks cool, but $200 is still $200. However I am looking at these new tilt-shift lenses from Schneider for digital SLRs, and the prices are around $4,000. ACK! I dunno about the rest of you, but if I had a spare $4gs sitting around that had to spent on camera gear, there are some real pretty 8x10 field cameras I would be looking at first. :)

Apologies if anyone has already covered this here in the forum, I looked, but couldn't see anything specific for this back. Also apologies if I am crossing the line between formats too much here, but personally, when I hike, I often take BOTH my 4x5 and my digital SLR and if this thing is actually any good, it might be great for me

thanks
joe

[Corran]

I'm confused as to how it connects to a camera. It doesn't look like a standard Graflok back.

[John Brady]

Bryan, with the lens removed from a dslr you mount the camera to the back and then mount the sliding back in place of the ground glass on your 4x5. Your camera becomes the digital back on a view camera. The back slides so you can stitch exposures. You can use live view to focus.

The main problem is the sensor is so far back that even your wide lenses become very long.

I have one but for me it isn't practical to use. The build quality is nice and worth the money.

I would stick to tilt shift lenses. I use the canon 17tse II and the 24tse II on a 5d II. With the camera set vertically on a tripod I stitch a series of images by shifting the lens from left, center and right. You end up with an image equivalent to 45 mp.

www.timeandlight.com

[Corran]

I see. While it makes panos easier I'm dubious it would make a difference compared to a good tele lens on a DSLR simply pointed to different locations, except for the ability to tilt. I'd love to try the thing though.

[Leigh]

The main problem is the sensor is so far back that even your wide lenses become very long.
The change of viewing angle is a consequence of the small size of the sensor, not of its distance from the lens.

- Leigh

[John Brady]

The change of viewing angle is a consequence of the small size of the sensor, not of its distance from the lens.

- Leigh

You are correct, brain lapse! The problem was you can't focus wide lenses because the sensor is to far from the lens. I think the shortest lens I could focus was a 240 and with the 35 mm sensor it was very telephoto.

Sorry for the mistake.

[David A. Goldfarb]

I have one. You get a certain amount of mechanical vignetting, if you stitch, and to stitch successfully, it helps if you're using artificial lighting, but with stitching, depending on the lens and subject distance, you might be able to have the equivalent of around a 60-80mm square sensor with a 5DII on the back using rear rise/fall and shift to move the sensor around. You won't be able to use the entire 4x5" image area on a 4x5" camera. It can be useful for tabletop setups where you want that kind of resolution (say, around 50+ Mpix), and you won't be using very wide lenses.

Here's how it looks on a 4x5" Tech V--

http://www.flickr.com/photos/davidagoldfarb/5676558373/in/photostream

and here's a sample image with an effective sensor area of 24x96mm--

http://www.flickr.com/photos/davidagoldfarb/4537823087/

So if you have a 4x5" set up and a sliding back like this, it gives you more flexibility than a 90mm TS lens for tabletop work, but it isn't a substitute for a wider TS lens. It also gives you a way to use classic soft focus lenses on a DSLR.

For tabletop, I usually use it on the back of a Sinar P with the double-bag bellows, but I haven't needed it recently. The 45mm TS-E is usually adequate.

[Leigh]

You are correct, brain lapse! The problem was you can't focus wide lenses because the sensor is to [sic] far from the lens.
That's correct.

The relevant specification is the "flange focal length" (FFL) of the lens, which is not the same as the focal length.

The FFL is the distance from the film to the lens mounting surface (lensboard on a large format camera) when focused at infinity. It's a fixed value for any particular lens model. For wide-ange lenses this distance is usually greater than the focal length, but not by a huge amount.

That would certainly pose a problem when trying to use a short focal-length lens with a DSLR body mounted.

- Leigh

[Greg Lockrey]

If you use a mirrorless camera like an Olympus E-P1 4/3rds you don't get the vignetting that you get from a DSLR due to mirror box casting a shadow. I've been able to stitch 4x4" equivalent squares with my set up with a Sinaron LE 180mm macro lens. They run about 485 mb @ 16 bit.

[TheDeardorffGuy]

In 1984 Deardorff made a 6x6 lensboard with a Nikon T mount mounted to it. This lensboard fit on a 12x12 inch adapter that fit on the back of a V8. Just like this thing from China does. At the time I used it to test the center image of my lenses. It was great to shoot Kodachrome and project it. Figure it out....You are getting HUGE magnifications of a tiny section of sheet film and you can see how your lenses are performing. My two sharpest lenses? A 190 Raptar and a 21inch Artar. Were the rest of my lenses bad. not at all. They would print just fine.

[Joseph O'Neil]

In 1984 Deardorff made a 6x6 lensboard with a Nikon T mount mounted to it. This lensboard fit on a 12x12 inch adapter that fit on the back of a V8. Just like this thing from China does. At the time I used it to test the center image of my lenses. It was great to shoot Kodachrome and project it. Figure it out....You are getting HUGE magnifications of a tiny section of sheet film and you can see how your lenses are performing. My two sharpest lenses? A 190 Raptar and a 21inch Artar. Were the rest of my lenses bad. not at all. They would print just fine.

Interesting you say that, because I have a few spare Nikon T-rings around here, and it would be next to nothing for me to make myself a board that would fit on the back of one of my 4x5 with the t-ring attached. What I would be missing would be the fine motion controls that the commcerial adaptor appears to have. I am also worried about how this adaptor would fit to the back of my camera. I am thinking I might have to rig something up.

Thanks to everyone who wrote, at the very leat, I might try making myself one before spending the bucks. I never considered it before, but now most DSLRs ahve mirror lockup & live view, so in theory you should be able to focus.

joe

[Jim Jones]

Decades ago I made such an adaptor to fit a Nikon on a 5x7 B&J, but don't remember ever using it. One large sheet of film seemed so much more practical. Maybe now in the digital age it will finally be good for something.

[David A. Goldfarb]

I never considered it before, but now most DSLRs ahve mirror lockup & live view, so in theory you should be able to focus.

joe

Yes, that's no problem at all. I find that if I'm going to stitch, I compose on the groundglass normally applying movements, etc., then attach the adapter back and DSLR, and it just takes one refocusing to compensate for the distance between the view camera film plane and the DSLR's image plane, and I can focus in live view magnified 10X.

[D. Bryant]

Yes, that's no problem at all. I find that if I'm going to stitch, I compose on the groundglass normally applying movements, etc., then attach the adapter back and DSLR, and it just takes one refocusing to compensate for the distance between the view camera film plane and the DSLR's image plane, and I can focus in live view magnified 10X.
David,

Do you have any samples of your stitches online?

[Ari]

David,

Do you have any samples of your stitches online?

See post #7