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papah
5-Dec-2009, 20:58
I'm using a Camera Fusion Metaformat Stitching Back on my Cambo 4x5 with a Nikon D5000 camera as imager. Here is an image shot from my lab window:
http://hemingway.cs.washington.edu/portfolio/pano/Velo-3.jpg
Full-size digital output is 22307 x 7803 pixels, approx. 174 megapixels, cropped down from 6 cm x 12 cm size of 220 megapixels stitched from 55 images.

Several versions of this shot, and Zoomify full-size versions can be seen at:
http://www.brucehemingway.com/pano/velo.html

I plan to use this setup to evaluate several soft-focus lenses.

Jim Galli
5-Dec-2009, 22:03
Interesting. How did you have the Velo set up? Aperture. Fuzz-u-lator? What size area did you look at with the lens? 6 cm X 12 cm? Can you scan a larger area than that? You'll need to take into account the format the original lens was designed for to get the full impact of the various designs. That would be especially true with lenses like plasticca and petzvals that are center sharp and then the bokeh changes the farther you move from center. The Velo was probably a good place to start.

papah
6-Dec-2009, 01:38
Jim,

The velo was wide-open, set at the sharpest setting for this initial testing. Here is the uncropped raw image out of the stitcher:

http://hemingway.cs.washington.edu/portfolio//pano/velo-test00.jpg

This is 23779 x 9691 pixels, which is 130mm x 53mm with the D5000 in landscape orientation. I cropped it to delete the shadow of the window frame and the light reflection in the upper right of the window. This a composite of 5 rows of 11 shots each.

Using the camera mounted in the portrait orientation would allow for the 120mm x 60mm that Camera Fusion claims. I use live view to focus, and set exposure manually. Of course, one could use lens movements and stitch multiple composites together, which may allow seeing the edge effects of some lenses.

Once set up, I can shoot the 55 images in in 3 or 4 minutes, which is much faster than a Betterlight scan. In addition, since individual exposures are relatively short, small motion artifacts are minimal; however, I'm not shooting sports :) .

At 182 pixels/mm, this is very high pixel density. This is much less expensive, as well. Autopano Giga is virtually automatic, but requires significant processing power.

I can't wait to crank up the fuzz-u-lator-- I've already removed the adjustment stop. Next up: the Kodak Portrait lens, and the Dallmeyer Patent Portrait Petzval 2B!

Steven Tribe
6-Dec-2009, 07:21
Now this is very very interesting. Is this set-up with a lap-top under shooting (battery life!).

papah
6-Dec-2009, 14:21
I shoot non-tethered with the battery in the D5000. Nikon battery usage is great; one battery lasts for hundreds of shots, even with use of the LCD. With my D3 I get over 1000 shots per charge. No laptop in the field, just the camera and memory cards. This is the principal reason, along with cost and pixel density, that I didn't buy a Betterlight.

The CameraFusion back has a ground glass unit that I use for composing the shot. Then I mount the sliding back, determine exposure, check final focus through viewfinder or with live view on the rotating lcd, and then make the 55 shots, sliding the back for each shot.

There is much more information on the CameraFusion website.
http://www.camerafusion.com/

Several notes: the D5000 doesn't meter directly; one would need a D300S to meter. But manual metering using the camera's histogram is no problem. (I've installed a cpu-chip in the back's camera mount so that the D5000 thinks it is seeing a Nikkor lens and will meter. But then I'm an electronics junkie.:) )

Even higher pixel density is possible with the use of a GH1 or other m4/3 camera: 220 pixels/mm vs 180 pixels/mm. A lens adapter would make mounting possible, I think.

The CameraFusion back doesn't work very well with full-frame SLRs. The mirror housing casts shadows. I can't use my D3 very well this way, hence the purchase of a D5000 for this purpose.

Mike1234
6-Dec-2009, 14:41
I've been considering this technique using a Canham 5x7 tradition to output 5x12 panos but with film and a flatbed scanner.

Gordon Coale
6-Dec-2009, 22:12
I plan on doing this with a Panasonic G1 mounted on a lens board on the back of a Toyo View D45M and use the shift and rise on the rear standard to move the G1 for stitching. It limits camera movements that the Camera Fusion Metaformat Stitching Back gives you but it does cost a lot less. I need to have my machinist make a retaining ring to screw into my M42 adapter to hold the G1 on the lens board. The G1 will even fit in a recessed lens board. And being a live view camera, you can focus and meter with it.

Putting a digital camera on the back of a view camera as a stitching camera makes for all sorts of interesting possibilities.