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12-29-2010, 10:37 AM   #46
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QuoteOriginally posted by Bobe416 Quote
I just looked up the DOF numbers for a 50mm lens.
If I got it right;
- at f11 with a 5 foot distance from the object, the in focus area is 4' 4.9'' to 5' 9.2''
- at f8 the in focus area is 4' 6.8'' to 5' 6.2''
So I suspect a 50mm will do the "shoe" job with a little cropping in post processing

On a K-x camera (sensor 23.6mm wide) a 50mm lens at 5' yields a field width of 50/23.6 = 5'/width or:

Width = 5*23.6/50 = 2.36'

That is close to being ok. It may be a little too wide for the shoe I think. If you crop, I believe DOF falls in proportion to the crop percentage, but the DoF you quoted is likely to be sufficient to accommodate the cropping needed.

It certainly looks feasible.

Aren't numeric estimates great?

12-29-2010, 12:31 PM   #47
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QuoteOriginally posted by RioRico Quote
Indeed. But that requires a rather severe tilt, right? Do any Pentax-compatible T/S setups tilt far enough? Any WIDE setups? By setup I mean a T/S lens, or a lens on a T/S adapter. I know that severe tilts are possible with MF cams, but AFAIK not with smaller formats.
I'm suspect I could do it on my (Pentax M42) tilt bellows (when I finally have time, I will post a thread about this setup, which I haven't actually tried out yet), which allows for severe tilts--the only issue would be how large an imaging circle the enlarger lens had.
12-30-2010, 07:39 AM   #48
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Lens Tilt vs Focal Plane tilt

QuoteOriginally posted by RioRico Quote
..... Do any Pentax-compatible T/S setups tilt far enough? Any WIDE setups? By setup I mean a T/S lens, or a lens on a T/S adapter...............
Here's a brief illustration of a Pentax camera's approximate field width vs lens tilt for a couple viewing angles;

Viewing angle = 45 degrees:
Width... Lens_Tilt_degrees
5cm............18
10cm..........11
50cm............3
100cm..........1


Viewing angle = 30 degrees
Width... Lens_Tilt_degrees
5cm............30
10cm..........19
50cm............5
100cm..........2


As you can see, the Lens Tilt required to put an entire tilted plane into focus is small until the desired field width is small.
12-30-2010, 01:00 PM   #49
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I've seen people mount DSLRs to the back of a view camera to use the tilts, shifts, swings etc. One problem, sharp and wide large format lenses are expensive! It could be a nice alternative... If you already have a large format setup sitting around.

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