Question on sharpness setting under LCC correction tab Capture One

[Paul2660]

I have noticed that if you are working in Capture One 6.3.4, under the LCC correction tab and then pick the sharpness setting which is directly above the Light fall off setting, the sharpness is applied to the entire image, not just the edges. I thought that the sharpness was only supposed to work on the outer edges where you would have possible fall off due to use of the outer edge of the image circle, i.e. 15mm of full shift on a 43mm schneider.

Instead it definitely applies the sharpness to the entire frame about the same which oversharpens the rest of the image.

When I used to use the Len correction tab with the Mamiya 35mm, the sharpness tab only effected the edges, but as I recall it also used to be called something different like "Edge sharpness falloff"

Has anyone else noticed this? Currently I have to process two images if the shifted image needs correction the blend them together.

I am going to try a local adjustment which does have a sharpness setting to see if I can get it to work better that way.

Thanks
paul

 

[Steve Hendrix]

I have noticed that if you are working in Capture One 6.3.4, under the LCC correction tab and then pick the sharpness setting which is directly above the Light fall off setting, the sharpness is applied to the entire image, not just the edges. I thought that the sharpness was only supposed to work on the outer edges where you would have possible fall off due to use of the outer edge of the image circle, i.e. 15mm of full shift on a 43mm schneider.

Instead it definitely applies the sharpness to the entire frame about the same which oversharpens the rest of the image.

When I used to use the Len correction tab with the Mamiya 35mm, the sharpness tab only effected the edges, but as I recall it also used to be called something different like "Edge sharpness falloff"

Has anyone else noticed this? Currently I have to process two images if the shifted image needs correction the blend them together.

I am going to try a local adjustment which does have a sharpness setting to see if I can get it to work better that way.

Thanks
paul

Paul -

Without going back to my archived C1 versions and checking the original implementation of this tool, I won't know for sure if it has evolved in how the range of sharpening is applied. So I can't be sure, but I do think it is possible that if you looked closely at images that did not have the sharpness falloff applied from prior versions of C1, you might see some center sharpening compared to the raw version of the file (depending on how much sharpness falloff you added).

It would depend on the amount of sharpness you applied. Currently, I can easily see center sharpness being enhanced at 100% (others may see it even a bit sooner). However, when I compare the same sharpness settings (all the way up to 250, for example, to make it obvious) and view the center and edge of the same image, captured with a lens that falls off at the edges (in this case Mamiya 35mm), then it appears to me that while both the center and edge seem to now possess a similar level of sharpness, the "before" level of sharpness was certainly in favor of the center.

From this result, I am then concluding that rather than just a blind "amount", the sharpness falloff tool may also be trying to detect contrast so that the algorithm is applied appropriately to both edge and center. Despite adding 250 points to the image, if that produced a satisfactory result at the edge, then the center doesn't seem to be less sharp. It appears to have been sharpened so they are somewhat in sync. Of course 250 isn't usually an ideal level to apply even for the edge, this was just to illustrate better the results.



Steve Hendrix

 

[Paul2660]

Steve:

Thanks for the reply. I worked up a few more files and again to my eye on a shifted image say 15mm of left shift with the 43mm or 60mm Schneiders, the effect is to basically oversharpen the center/right of the image. I never noticed this before with the 35mm Mamiya but it is most definitely not as sharp on center as the Schneiders.

It's an easy fix, I just didn't use the sharpening in the LCC correction and added some in a local adjustment. Hopefully Phase One will be allowing for more of these (local adjustments) in future versions as the limit of 5 per image is a major shortfall. Once you start working with local adjustments I find that it really gives you a lot of precise control over the image in question.

Paul