Sure,thank you. Iām going to place the samples in the attachments. These are screenshots taken either saved jpegs or over RT working screen.
Please note, that the image quality didnāt change at all after performing āFlip horizontallyā.
āthat you will always see some degradation when you do a slight angular adjustmentā
-why, then any preset angle change (90 deg left or right, or Flop vertically or Flop horizontally doesnāt seem to affect the image quality at all ?
Iām not printing these images yet (or maybe ever), but an image quality in macro is very important . If the depth of field is a millimetre or so, any deterioration in sharpness renders such an image useless.
āflip horizontalā is just a relocation of the unmodified pixels from one side of the image rectangle to the other. Itās when you do an angular rotation that an interpolation is required that changes the pixels.
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Well, what do we learn out of this? In a macro donāt modify angles. Iām pretty sure, nobody will realize that you didnāt do it ā¦
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For any non-trivial rotations (i.e. anything else than multiples of 90Ā°), the pixel values have to be interpolated. This will always introduce artifacts or unsharpness.
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Is it the same in case of 90 deg flop? Because even in this case the grasshopper is still doing fine.
Only the gradual angle change affects it badly.
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Rotations in multiples of 90Ā° wonāt have the problem because they can be performed by swapping pixels
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Yes, itās the angles between the major orientations (90, 180, 270, vertical/horizontal reversing) that introduce the need to interpolate the pixels to their new locations.
Your first screenshot does not look like a 100% preview. Preview for less than 100% often is less sharp then preview at 100%
Unfortunately, wildlife rarely complies with photographerās requirementsā¦
Yes, I probably took the first screenshot over smaller enlargement. But it doesnāt mean that at 100% it looks better;on contrary it looks worse under greater magnification in RAW.
I see. Would it be the case with any RAW editor?
What camera do you use?
I ask because, if youāre going to have to rotate images to get the right composition (I get that, some subjects and situations donāt let you compose optimally in-camera), your sensor resolution may be exposing the rotation artifacts more egregiously. My best camera is 24MP; I wouldnāt expect images from it to perform in rotation as well as equivalent images from, say, a 42MP camera.
I donāt have direct observation experience amongst softwares, but I would think so. Thereās only so much a rotation algorithm can do to preserve the local pixel relationships in arbitrary-angle rotations. Oh, I do have rotation experience; Iāve cobbled together a bi-linear rotation algorithm for my hack software.
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As a very first step I would disable Auto-fill and then crop off the resulting black borders. That should give you a much better result.
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Thanks! Iām going to try this. i also will try to experiment in GIMP over the same parameters.
Auto-fill upsizes the image (because it tries to keep the image dimensions after rotation) and so leads to less sharp result, especially if it has to upsize a lot.
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I used Pentax K5iis (16.3MP) for this sample but Iāve been in the same situation before, with Pentax KP (24MP) and it was the same story developing in RT. I actually think that higher MP would show even worse deterioration.
Thanks! I definitely will. Canāt do anything right now, Iām on my way to work.
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It works ! You were right !
Iāve disabled the āAuto fillā only and did not notice any changes in sharpness or micro contrast after performing fine angle adjustment .
Applying an āAuto-cropā or doing the cropping manually after "Auto fillā cancellation doesnāt affect the image quality either.
Thank you!
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