Mixing images with Zerene?

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soldevilla
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Mixing images with Zerene?

Post by soldevilla »

Hello, I have a question about the operation of Zerene. We will imagine that with a specific optical system, using 0,1 mm steps we are no longer able to differentiate bands blur in the image. At this point increasing the number of images by decreasing the step size has an influence on the final quality of the image? Zerene makes a kind of average between those focused areas from several images, or there is no improvement by this extra work?

rjlittlefield
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Re: Mixing images with Zerene?

Post by rjlittlefield »

soldevilla wrote:we are no longer able to differentiate bands blur in the image
...
Zerene makes a kind of average between those focused areas from several images, or there is no improvement by this extra work?
Short answer: no averaging, no improvement.

A longer explanation... Because all images are noisy to some degree, ZS will always find differences between frames, even if you shoot several frames with exactly the same focus. PMax always pulls each level of detail from exactly one frame. DMap always computes exactly one depth for each pixel. If that depth happens to lie between two frames, then DMap will make a weighted average of those two frames. Except for this case, DMap pulls pixel values from exactly one frame also.

Some people like to shoot very fine focus steps, several times smaller than the 1/4-lambda rule suggests. Especially with PMax, this will certainly produce an image that appears to contain more detail. Whether it actually contains more detail, or has just accumulated more noise that is perceived as detail, is still not completely resolved. See HERE and following for some illustration and discussion.

--Rik

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