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01-17-2015, 12:06 AM   #31
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The only benefits you get from using a 645 lens on a K-3 or any 35mm camera, is flatness of field.

The focal length remains the same Regardless of what type lens you use. Only the image circle changes.

The usable portion of that image circle will be determined by the size of the film/sensor. Limiting your field of view.

Think of it like looking through a paper tube. a short paper tube, will give you one view. Double the length of the paper tube, And you will see less of the image. Magnification does not change only the field-of-view. However when printing, the relative image size will become apparent, and an increase magnification will be simulated. but only when printing on the same size paper. If you print them on paper relative to their sensor size, The subject would be the same size, but the larger sensor size will give you a larger field of view. you can achieve the same effect by cropping the larger sensor down to represent the aspect ratio of the smaller sensor. but you cannot go the other way.

It is a perceived magnification when printed on the same size paper.

01-17-2015, 09:40 AM   #32

Join Date: May 2010
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Ohh. My hangup was example 1 as I already understood example 2's concept.. but I think I understand now. The issue is the way I am looking at the chart and generally thinking about the concepts -- I only see data for Example 2 (different sensor size, same focal length[w/ lenses designed for different format) and not Example1 (same sensor size, same focal length [again w/ lenses designed for different format]) and I was attempting to understand 1 based mostly on the chart (as well as in general) and thought both examples were explained by the chart.

Thanks to everyone who took time to respond! A lot of information here.. the key is in focusing it into proper lanes and not mixing it together (as there are different concepts described)!

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