Sunday, March 6, 2011

4x5 + DSLR An Experiment

I did an experiment recently to see if I could use my DSLR with my view camera.

I have seen the digital scanning backs or medium format digital backs people have purchased but the several kilobuck price tags places them clearly out of my budget.

Then I saw that some people were buying adapters to allow the use of their DSLR with their view camera. The price was only a couple of hundred, so it was of more real potential.

Then the brainstorm happened....

The modular nature of an Arca-Swiss camera means the ground glass uses the same frame as a lensboard. Meaning I thought I could mount the camera to a flat lens board and use it in place of the ground glass.

I had a flat lensboard so I bought a cheap $15 set of extension tubes off ebay. A buddy took the flat lensboard, took the #1 sized lensboard hole and widened it a bit. Then he epoxied the extension tubes to it.

Viola!-an instant digital camera mount.

The only thing we had to do was play with the extension tube pieces until we got right distance so the camera prism could clear the board.

Once we had that, all I had to do was pop off the ground glass, pop on the new lens board, and mount my Canon DSLR on the extension tubes.

It fit great.

Then with live view I could now compose and focus!

I was able to use both my 210mm and 125mm lens. Although it was a squeeze to make the 125mm work and in this setup anything shorter was out of the question. Remember since I am using the DSLR sensor the lenses act like they would on the DSLR too. So 125mm is slightly wide on the 4x5 but fairly long on the DSLR.

I was still using the large format lenses, still setting the aperture on them, still using movements too. I had just replaced film with a digital sensor. Albeit, a tiny one.

By using Aperture Priority mode on the camera plus live view, it was easy to focus and the camera could still get the exposure!

Images were sharp and had good color.

This not only worked, it had potential.

Then I expanded into what I was really hoping to do-use the movement features of the camera to stitch images into panoramas.

That was when I found the limits.

The Arca-Swiss model I have-the Discovery has all that Arca modularity but it also has friction movements.

Meaning that to shift, I have to loosen a knob, slide the frame, and retighten the knob. What I found was there was ever so slight focus shift when I did that.

So the stitching of panos was lost. Or at least I found it was much easier just to hand hold and use the DSLR as opposed to using the view camera and DSLR to try to stitch.

So an experiment that kinda worked.

I can use it and get an image. however I think you would need a camera with geared movements to take advantage of the shift and stitch.

So the merger of digital and large format is still not happening for me. I'll just do hand held stitches with the DSLR and stick to film with the view camera.