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Old Sep 7, 2010, 1:44 PM   #51
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How about this one.... what is it doing to our DOF as all the shots are with the same camera http://blog.buiphotography.com/2009/...th-directions/
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Old Sep 7, 2010, 3:01 PM   #52
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That looks like HDR for DoF.
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Old Sep 7, 2010, 5:01 PM   #53
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Yeah, well you can do it handheld or use one of the motorized panoramic heads. Which seems more sensible to me. Sure as heck beats a scanning back, or even medium format digital.

Take a Sony A850 or Canon 5DMk2 with a motorized panoramic head and you are going to spend way less than MF digital, and end up with much higher resolution images.

http://www.roundshot.ch/xml_1/intern.../d927/f850.cfm

http://gigapansystems.com/gigapan-pr...duct-page.html
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Old Sep 7, 2010, 5:03 PM   #54
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Quote:
Originally Posted by peripatetic View Post
Yeah, well you can do it handheld or use one of the motorized panoramic heads. Which seems more sensible to me. Sure as heck beats a scanning back, or even medium format digital.

Take a Sony A850 or Canon 5DMk2 with a motorized panoramic head and you are going to spend way less than MF digital, and end up with much higher resolution images.

http://www.roundshot.ch/xml_1/intern.../d927/f850.cfm

http://gigapansystems.com/gigapan-pr...duct-page.html
But you didn't answer the question that I thought I inferred related to this thread..... what's it doing to the DOF
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Old Sep 7, 2010, 5:33 PM   #55
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It's a composite image that has the same DoF as each of the component images.
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Old Sep 7, 2010, 9:38 PM   #56
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In effect, using this method, you are changing the film format to something a lot larger, thereby reducing DOF for the image. (85mm at f/1/4 gives you a very different look on MF than on 35mm)

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Old Sep 8, 2010, 8:13 AM   #57
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Quote:
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In effect, using this method, you are changing the film format to something a lot larger, thereby reducing DOF for the image. (85mm at f/1/4 gives you a very different look on MF than on 35mm)

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Brian - you said earlier:
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DOF is a property of the lens focal length/aperture/and camera format.
This method simply puts multiple photos together - like a panorama. It's editing photos after the fact. Which is it Brian - is DOF locked in when the photo is snapped or does photo manipulation change DOF? You can't have it both ways.
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Old Sep 8, 2010, 8:15 AM   #58
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Another quote from you Brian:
Quote:
TCav has got this right - the DOF is determined when the shot is taken.
I point this out only because you are so adamant earlier. This is photo manipulation now - so is DOF locked in at the time the shot is taken or can it be altered by manipulating the photos?
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Old Sep 8, 2010, 8:42 AM   #59
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Sorry, but I don't see any inconsistencies. If I shoot x number of exposures at 300mm F/4, and stitch them together to get a FOV equivalent to a 50mm lens, the overall picture has the DOF of the 300mm lens, not changing the DOF, but if the overall shot is viewed as a 50mm, it will be reduced from what is expected of the 50. This is consistent with the DOF being fixed at the time the picture is taken. You increase the size of the 'film', even if it is done after the fact.
But I was talking about single exposres, anyway.

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Old Sep 8, 2010, 9:03 AM   #60
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Quote:
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... This is photo manipulation now - so is DOF locked in at the time the shot is taken or can it be altered by manipulating the photos?
No, it can't be altered by manipulating the photos.

Suppose that each of the component images, from left to right in the composite image, were shot at progressively smaller apertures. In the author's example, for instance, the component images in the leftmost column might have been shot with an aperture of f/1.4, and the component images in each successive column would have been shot with an aperture 1/3 stop smaller. The subject would be captured with an aperture ranging from f/2.8 to f/3.5, and the rightmost column of component images would be shot with an aperture of f/6.3. The DoF would differ across the composite image, because the DoF varied from one component image to another. That can only be done at the time the shutter button is depressed (for each component image.)

How could that be changed after the fact?
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