Tilt Shift with the a-Mount

Thanks everyone for your comments and support! When the Samyang T/S comes out in a few months, I'll probably post some updates to this article, at which point I'll go through all your comments again and include many of them in my revision.

Shooting on a cropped sensor SLT, I really appreciate the fuctionality that the EVF gives me in easily composing and previewing with my T/S bendycam. But it's not clear to me why it would be that much more difficult to use a T/S on an A850 or A900. I know that they have optical viewfinders (which have advantages and disadvantages), but CaNikon T/S lenses are all developed for optical viewfinder cameras, and CaNikon users seem fine with it.

Thinking on it, Sony has the advantage of having in-body stabilization if you can chip your lens, while CaNikon T/S shooters don't have the option of a stabilized T/S lens, as far as I know. Another advantage to Alpha shooters.

Ian

ifreedman wrote: But it's not clear to me why it would be that much more difficult to use a T/S on an A850 or A900. I know that they have optical viewfinders (which have advantages and disadvantages), but CaNikon T/S lenses are all developed for optical viewfinder cameras, and CaNikon users seem fine with it. Ian

Shift isn't a problem. One may use hyperfocal focusing, and get repeatable results (as with any lens with a distance scale).

Focusing with tilt is determined by the degree of the lens, and anything past the immediate foreground is difficult to discern in an OVF. One may develop a table, relying on direct observation of the exposed image,recording the tilt angle, aperture, and lens distance and achieve repeatable results to some degree. The problem there is most lenses don't have a finely graduated scale, so there's still a lot of guesswork.

I have a "type M" screen installed on my a850. It's better than the stock screen for manual focusing, at the expense of a slightly darker VF. Combine that with a stopped down lens (my Mamiya 35mm is f/3.5 wide open), and the low light we landscape photographers face in the "golden hour", and it can be very difficult to see through the OVF, much less establish critical focus. Auto gain with live view is the answer.

Graham

Edit: Regarding CaNikon users "seeming fine" with their T/S lenses and optical viewfinders. CaNikon have had live view lcd's to augment their OVF's for some time.

Edited by GrahamB - 31 December 2012 at 14:50

Great guide Ian, thanks for this, i'm still planning on a DIY jobby at some point/

Thank you Ian, i found a lot of answers in this very interesting post.

Thanks, very interesting. I carried out a practical experiment for tilt in macro mode, using my Miranda Focabell S and the short-barrel 135mm f3.5 Miranda telephoto designed for it. The Focabell S (the cheaper and less rare of the two Miranda bellows devices) has a pivot already to allow it to fold up, and if the unit is mounted on the camera upside down, then it allows the lens and bellows to tilt down rather than up.

This allows an angled view of a flat surface to be in focus even in macro and seems to work on the brief trials I did. And as the focabell & 135mm are FF, there didn't seem to be any obvious vignetting. I will try to make a stiffer pivot for practicality and test it on some flowers & insects.

Incidentally, the short-barrel lens allows focussing to infinity even with a bellows atachment, so use on non-macro subjects should be possible too, though near infinity the unit won't tilt unless the bellows mounting is cut back. Presumably some more common Minolta lenses could be modified to remove the back ends of their barrels & mountings.

Ahoy!

I don't know how it compares, but you can upload images to a free tilt-shift effect website that will adjust the image according to your input info and the results are excellent, but as it's free, there's no harm in trying it. If you scroll down, you'll see converted images here.

I hope this works out for you!!! Let us know how it goes.