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S1R sharpening in RAW (LR)


Donzo98

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Are you guys noticing you need higher sharpening amounts on the 47mp sensor, then you did with the SL (24MP)?

Using my best glass wide open (SL primes)... I kind of think the pinpoint sharpness isn't there at standard levels (around 40), like it was on the SL. 

I wonder if the IBIS is slightly degrading the image. I mean... it's nothing crazy, just wondering.

Edited by Donzo98
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8 minutes ago, Donzo98 said:

Are you guys noticing you need higher sharpening amounts on the 47mp sensor, then you did with the SL (24MP)?

That depends upon your output size. Sharpening a 47mp image doesn't do anything if you reduce the image for the 'net or printing realistic sizes. Printers use their own proprietary resizing/resampling routines.

Sharpen appropriately for presentation media and size.

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It could be.  But I also noticed that when I first tried the HighRes option with the shutter on mechanical, it wasn't very sharp.  Going to full-time electronic it worked much better.   So eliminate all sources of vibration before deciding what the baseline processing should be.  Handheld with mechanical shutter I'm getting pretty sharp pictures -- faces of people in a crowd 100' away are rendered well. I define "sharp" by how the pictures look when rendered at 100% and then shown actual size on my screen.  Even though I'm the only one who gets to see them that way.

Edited by scott kirkpatrick
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55 minutes ago, Donzo98 said:

Are you guys noticing you need higher sharpening amounts on the 47mp sensor, then you did with the SL (24MP)?

Using my best glass wide open (SL primes)... I kind of think the pinpoint sharpness isn't there at standard levels (around 40), like it was on the SL. 

I wonder if the IBIS is slightly degrading the image. I mean... it's nothing crazy, just wondering.

In my experience, More pixels require higher levels of sharpening.

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Sharpening with S1R images in LR is rather curious and I have played around a lot to see what settings give optimum detail ...... ok I concede it's not really necessary for most printing and images shared on the internet, but it's interesting to see just how much resolution you can wring out of a 47mpx file. They behave very differently to 24mpx SL images.

The main issue is the default Detail slider value of 25 in LR. You can push the amount of sharpening to 80-100 with most images and still get more detail .... but the default detail setting causes jaggies, granularity and artefacts. It needs progressively reducing as the amount of sharpening goes up ..... and as far as I can see with S1R images you might be better off just setting it to zero. 

As a result if I want to markedly sharpen images I tend to use a lot of masking (40-60), reduce detail to below 10 and often add a small amount of luminance noise reduction ..... there always seems to be an optimum point that varies between images that takes a bit of juggling about.

SL 75/2 images seem completely bomb-proof and you can sharpen them with minimal artefact and noise ..... but with other lenses and higher ISO's it all becomes more problematic. There is always a compromise with some areas becoming textureless in an effort to combat noise and other issues. 

Of course with 47mpx there is a perfectly valid argument that you don't need any sharpening at all ...... and a bit of added contrast and texture in processing will give you much the same results. I print A2 maximum and I suspect it makes not a scrap of difference at that print resolution. Anyway, it's fun to see how far you can push images in LR and see what happens ..... if only to avoid the results of over-processing in the future :rolleyes:

Edited by thighslapper
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Here's another challenge -- how do you sharpen the 8-shot super-resolution images that the S1R produces?  Here's a quick stab at it.  I shot books across the room (5 m distance) with the SL 75 @f/2.0, reduced the threshold and spot size to half their normal values, and increased sharpening strength by 50%.  The two samples are cropped to show a 15 cm wide section at full resolution (first example) 10 cm wide (second sample).

P1000701 1 by scott kirkpatrick, on Flickr

P1000699 by scott kirkpatrick, on Flickr

The problem in superresolution is that if the movements of the chip between the eight shots are precise, we most likely end up with twice the number of original pixels, each with all four colors accurately represented but arranged on a grid which is tilted at 45 degrees to the original pixel matrix.  And our pixels haven't gotten smaller, but overlap now.  The resulting image is interpolated back to the original grid orientation, with half the old spacing between the sloppy, virtual pixels so that we get 4X as many "pixels" as we started with.  What's needed is an entirely different rendering, since deBayering is no longer required but the pixels are now sloppy.

Edited by scott kirkpatrick
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