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Old Mar 11, 2007, 6:20 PM   #11
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ennacac wrote:
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I did not use a tripod, but I did take both photos from the same spot (possibly a 5 foot difference after I got done changing lenses from my bag) on the same day, but the angle of view difference is correct.
Tom, I'm not accusing you of anything so please don't take offense, but I'm with Ken on this one. On the second shot, the white shed to the left appears to have shrunk significantly compared to the shed right next to it. The fence to the right of the sheds appears to have moved about 10 feet to the left. A tree that's probably 100 feet away is well to the left of the windmill in the first shot, and in the second is obstructing it.

These shots couldn't be from the same place. It seems pretty clear the first shot was taken from much further back, compressing the perspective.
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Old Mar 11, 2007, 6:30 PM   #12
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The barn is exactly the same size!
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Old Mar 11, 2007, 6:37 PM   #13
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NonEntity1 wrote:
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The K10D will take three images of one subject at three different settings and then blend them together so the final photo has the same DR as film.
This is the same thing that HDR software does, right? I did not know tha the K10 could do this in camera also. Now I want one even more. Can you only do this with RAW or can you perform the same combination of three images in Jpeg mode?

Thanks,

Tim
Tim, this is from three jpg images of the Golden Gate Bridge that could not be done with one shot with the severe glare on the water on the right.

If you look closely you can see ghost images of cars as they moved between exposures.



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Old Mar 12, 2007, 1:38 AM   #14
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ennacac wrote:
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The barn is exactly the same size!
Here, this should make it pretty clear. I traced the two sheds, the fence in the foreground, and some of the trees in the background. I copied the traces and moved them over to the other shot so you can see where the differences are.

The white shed on the left has shrunk, the shed to the right is slightly larger and much further to the left, the fence moved way to the left, and the trees in the background shrunk to half their size. You're even able to see more power lines in the second photo that you couldn't in the first because they were in front of the trees.

The second shot was clearly taken with a much smaller focal length, probably a 28mm if the first one was 50mm.
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Old Mar 12, 2007, 8:25 AM   #15
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You still haven't said which shot is which. If I had to guess, I'd say the second shot is film, it looks to have more grain than the first.

I would guess that while changing lenses that you might have sidestepped a few feet to the right. I don't know that you moved forward or backward by much. I think the only way your're going to get the true 1:1 resluts you're looking for is with a tripod though.
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Old Mar 12, 2007, 9:52 AM   #16
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Basement Shows wrote:
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You still haven't said which shot is which. If I had to guess, I'd say the second shot is film, it looks to have more grain than the first.

I would guess that while changing lenses that you might have sidestepped a few feet to the right. I don't know that you moved forward or backward by much. I think the only way your're going to get the true 1:1 resluts you're looking for is with a tripod though.
Exactly! I did not use a tripod, stepped to the side to change cameras and put the same 50mm lens on the MZ-S and quite possibly side stepped a bit with the second shot.

The film shot is the one with the most information and DR in the resulting photograph and I resent some of you accusing me of using two different lenses in your effort to be anal about this example.

Reminds me of an old saying "Can't see the forest for the trees!"

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Old Mar 12, 2007, 3:19 PM   #17
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I suppose everyone's entitled to their own physics.
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Old Mar 12, 2007, 8:35 PM   #18
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Thanks Tom. Hopefully by this summer I will have a K10 in hand.

Tim
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Old Apr 5, 2007, 3:32 PM   #19
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"I suppose everyone's entitled to their own physics."
:-)

Maybe I wasn't clear enough about this. The DSLR has a 1.5 crop factor. So the equivalent focal length of the 50mm lens is now 75mm. I wasn't suggesting it was a different lens, just that the same lens that is a normal lens on the film camera is now a short telephoto lens on the dSLR.

To make the barn the same size from the same location, given that one shot is a 50mm EFL and the other a 75mm EFL, you would have to crop and enlarge the film image. But that wouldn't change perspective.

Since there is a differnce in perspective, it's clear that the 75mm EFL digital image was taken from a bit farther back. If it wasn't, that difference in effective focal length would also be more apparent. I wouldn't want anyone to be mislead about the degree of difference in moving the same lens from film to a typical consumer DSLR.

Didn't really want to revive this, but I think a thread on "crop factor" here ought to contain clearer information of what the crop factor actually does! The same lens on a 1.5 crop DSLR as a film SLR will always produce a 50% larger subject from the same place with no cropping of the final image.

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Old Apr 5, 2007, 4:14 PM   #20
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Focal length never changes no matter what camera the lens is on, it is a fixed physical characteristic of the lens.

" The focal length of a lens is defined as the distance in mm from the optical center of the lens to the focal point, which is located on the sensor or film if the subject (at infinity) is "in focus"."

http://www.dpreview.com/learn/?/Glos..._Length_01.htm

Only FOV changes!
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