PDA

View Full Version : Quick DIY 4x5 back adapter for Sony NEX digital



architorture
1-Jul-2012, 20:33
So, yesterday I got really excited when I came across a link to the multistitch (http://www.multistitch.com/)back on the forum. I spent all day drawing different variations of frame combinations and modeling some ideas in 3D on the computer.

It became pretty clear to me that instead of the multistitch ($950) or the Kapture Group Quadstitch ($2800), the same effect could be achieved with a low cost 4x5 sliding adapter for 35mm cameras that are under $200 on ebay, like this http://www.dirtimage.com/forsale/4x5-canon1.jpg. Simply using one of those with the back vertically, combined with rear-standard lateral shift to either side would get you a very large image!

With a 35mm DSLR a 3x3 composite produces an effective capture size of roughly 2.66 x 4.08in (with a canon 5d mkii that would be roughly 150MP).

Unfortunately for me, I do not have a 35mm DSLR... But I do have a Sony NEX-5N, which is conveniently small and light. Although the NEX-5N is nominally less MP than the Canon, it's pixel density is higher, so that despite a 3x3 composite covering less area (1.6 x 2.51in) the output resolution would be not much less (113MP).

All this is to say that I was itching to test the idea out for myself in reality. So I quickly slapped together some foamcore and chipboard, and voila:
76497

I have a very limited 4x5 kit, so all I could use was my Nikkor SW 65/4 and mystery camera (http://www.largeformatphotography.info/forum/showthread.php?91313-I-just-bought-this-thing-online-can-you-tell-me-anything-about-it). I didn't have an allen wrench on hand to reset the lens panel distance, so because the adapter shifts the focal plane back almost 1in I was restricted to a macro test:
76502

This is a 5-frame composite stitched with Hugin. The capture area is almost identical to a Hasseblad XPAN at 24x65mm. Resulting image size is 13,051 x 4,897 pixels, 60MP. Focus was only about 12in away. Shot at f/16, ISO 200, regular tungsten house light. If you'd like to download a full-size jpeg you can do so at http://www.mediafire.com/i/?jan4e95qd4vi8r5 If I had rear-standard shift capability I could easily expand the image to a 148MP 6x7cm image with 12 frames, a 300MP super-6x9cm image with 25frames, or further...

You can see some flare on the left and right of the image because the foamcore is white and because I shifted the panel a little too far. If it were made properly this would not be present.

Now I'd just love to do this properly, outside, with infinity focus, multi-row capability, etc.

Without movements, however, I am wondering what advantage this method gives, if any, over shooting a regular panorama...?

Does anybody else have experience doing something similar?

Eric Rose
1-Jul-2012, 21:48
Wow that is really cool. I just might have to jimmy something up for my D700 on my Cambo.

architorture
2-Jul-2012, 22:16
Made a second version with the mount offset from the center. This lets me shoot a 2-row composite by rotating the adapter 180 degrees. A more simple method than rear-standard shift, but more limited.

76556

The frame it produces is almost exactly the same as a 645 (11,337 x 8,501 px):
76558

100% crop:
76560

Not exactly exciting images, but the project is fun.

Unfortunately the manufacturing tolerances are not very tight on my mystery 4x5, and I cannot get the lens panel to fit in the rearmost position - it'll need some grinding to get to infinity...

Eric:
Definitely give it a try. I'm enjoying myself. And with your 24x36 sensor you'll be able to cover a lot more area with fewer frames.

These images were shot with ~6mm overlap, which I realize is more than necessary. With the pixel density of the NEX-5N an overlap closer to 3mm is probably sufficient for the stitching algorithm to work - and it means I could cover the same area with one less frame per row.

zenny
3-Jul-2012, 00:25
So, yesterday I got really excited when I came across a link to the multistitch (http://www.multistitch.com/)back on the forum. I spent all day drawing different variations of frame combinations and modeling some ideas in 3D on the computer.

It became pretty clear to me that instead of the multistitch ($950) or the Kapture Group Quadstitch ($2800), the same effect could be achieved with a low cost 4x5 sliding adapter for 35mm cameras that are under $200 on ebay, like this http://www.dirtimage.com/forsale/4x5-canon1.jpg. Simply using one of those with the back vertically, combined with rear-standard lateral shift to either side would get you a very large image!

With a 35mm DSLR a 3x3 composite produces an effective capture size of roughly 2.66 x 4.08in (with a canon 5d mkii that would be roughly 150MP).

Unfortunately for me, I do not have a 35mm DSLR... But I do have a Sony NEX-5N, which is conveniently small and light. Although the NEX-5N is nominally less MP than the Canon, it's pixel density is higher, so that despite a 3x3 composite covering less area (1.6 x 2.51in) the output resolution would be not much less (113MP).

All this is to say that I was itching to test the idea out for myself in reality. So I quickly slapped together some foamcore and chipboard, and voila:
76497

I have a very limited 4x5 kit, so all I could use was my Nikkor SW 65/4 and mystery camera (http://www.largeformatphotography.info/forum/showthread.php?91313-I-just-bought-this-thing-online-can-you-tell-me-anything-about-it). I didn't have an allen wrench on hand to reset the lens panel distance, so because the adapter shifts the focal plane back almost 1in I was restricted to a macro test:
76502

This is a 5-frame composite stitched with Hugin. The capture area is almost identical to a Hasseblad XPAN at 24x65mm. Resulting image size is 13,051 x 4,897 pixels, 60MP. Focus was only about 12in away. Shot at f/16, ISO 200, regular tungsten house light. If you'd like to download a full-size jpeg you can do so at http://www.mediafire.com/i/?jan4e95qd4vi8r5 If I had rear-standard shift capability I could easily expand the image to a 148MP 6x7cm image with 12 frames, a 300MP super-6x9cm image with 25frames, or further...

You can see some flare on the left and right of the image because the foamcore is white and because I shifted the panel a little too far. If it were made properly this would not be present.

Now I'd just love to do this properly, outside, with infinity focus, multi-row capability, etc.

Without movements, however, I am wondering what advantage this method gives, if any, over shooting a regular panorama...?

Does anybody else have experience doing something similar?

Pretty innovative mod! Congrats! Thanks for sharing.

Where did you get the adapter ring to mount the camera?

/zenny

architorture
3-Jul-2012, 06:36
Thanks Zenny.

Right now the "adapter ring" is just a tube of chipboard, sized to fit over the outside of the NEX mount. It holds the camera in place only by friction, and a piece of gaffer's tape for safety.

If I were to make a "real" version of this, I would buy a macro extension tube set, and use one or two pieces from that to get a proper bayonet mount. I also would not be using chipboard...

Michael Rosenberg
3-Jul-2012, 14:10
This is pretty neat! Do you have a lens on the camera? Is it on auto or manual focus? Are you using the Nex5 to focus, or the 4x5 lens? I have a Nex 7 that I would like to try this with.

Mike

architorture
3-Jul-2012, 14:39
This is pretty neat! Do you have a lens on the camera? Is it on auto or manual focus? Are you using the Nex5 to focus, or the 4x5 lens? I have a Nex 7 that I would like to try this with.

Mike

There is no lens on the NEX -I'm using my Nikkor SW 65/4 as the lens, mounted on my Mystery 4x5. The focus is achieved through the 4x5, with live-view on the NEX. Keep in mind that the sensor of the digital camera will most likely not fall at the same distance as the film would, so the lens will have to be moved back to a shorter distance than normal, in order to achieve the proper flange-focal distance to the sensor.

I focus with the lens wide open, and then stop down to the taking aperture, but keeping the shutter open. Then I adjust the ISO and shutter speed on the NEX for appropriate exposure, with the aid of the live-histogram. The shutter in the NEX takes the shot (the electronic first-curtain is ideal for this setup, eliminate any and all shutter-induced vibration).

Definitely give it a try with the NEX-7 - that's a pixel density of 43MP/in^2, or equivalent to scanning film at ~6,500dpi (my NEX-5n is 28.33MP/in^2 or ~5,300dpi). You'll get some big files!