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Does digital sharpening cause chromatic aberrations?

Chapperz

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I'm just a noob at this so forgive me if I'm missing something or am just ignorant.

I would have thought that sharpening an image would reduce CA because I would assume that it would focus the different frequencies of light on to a smaller point.

Now it might well be me doing something wrong but, with my mini 3 Pro in 48mp mode, the sharpening seems to be exacerbating the issue.

It seems like the sharpening is exacerbating the issue and the noise reduction is just smudging the results...

Or am I imagining it?
 
It seems like the sharpening is exacerbating the issue and the noise reduction is just smudging the results...
That is generally correct. But there are different techniques to sharpen a photo, and some gives worse result than others. But essentially sharpening works by exaggerating the brightness difference along edges within an image. And CA will be more apparent the more sharpening you apply.
Have a look here, a good guide to sharpening: Guide to Image Sharpening
 
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That is generally correct. But there are different techniques to sharpen a photo, and some gives worse result than others. But essentially sharpening works by exaggerating the brightness difference along edges within an image. And CA will be more apparent the more sharpening you apply.
Have a look here, a good guide to sharpening: Guide to Image Sharpening
Ahhhh thanks for confirming that for me... From now on I will be leaving the sharpening to Lr.

Apparently, noise reduction softens an image so it seems counterintuitive to sharpen an image and then de-noise... It's like chasing ya tail as far as I can tell.

I'm just going to leave them both right down. The theory behind that less sharpening means less CA and less noise reduction means that the sharpness and details that are the will be preserved, then I will use Lr to do the above because I'd expected Lr to be a whole lot better than the dji mini 3 Pro built in stuff.

Thanks again
 
Under the lens correction section in LR, there is an option to remove chromatic aberration. I use this to process pix I take with one of my telephoto lenses I have for my Canon dslr.
 
Under the lens correction section in LR, there is an option to remove chromatic aberration. I use this to process pix I take with one of my telephoto lenses I have for my Canon dslr.
I discovered that the other week... The issue I have is that the built in sharpness and noise reduction in the dji mini 3 Pro, as far as my noob self can tell is utter tosh... The sharpening just adds (or exacerbates) CA and then the NR just smudges what details are there.

I have come to the conclusion that that leaving all the dji stuff off and doing it in Lr is the best way. More work but I'm happy with that if the end result is a 48mp image I can enlarge to say a A2 size and display.

The way I'm looking at it is using some that is designed to do that job specifically is going to be better.

If you think about it. Ya only have a tiny bit of space for code in the dji and limited processing power, with a pc, well, you get the point.

That said, I'm a noob so I may well have it all arse about face... In which case I'm going to learn the hard way lol
 
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Apparently, noise reduction softens an image so it seems counterintuitive to sharpen an image and then de-noise... It's like chasing ya tail as far as I can tell.
Exactly. I am one of those that does not panic when there is a little noise (or grain as I prefer to call it, from the old film days.)
Noise reduction has to be applied carefully, too many photos nowadays look like they are smeared with vaseline.
But noise in digital photos are several things. The worst is colour noise, but most raw developers have effective tools for removing it. What is left is a slightly grainy look which is almost impossible to remove without getting that "smudgy" look. As long as the grain is random, not in a unform pattern, it does not matter to me.
 
Exactly. I am one of those that does not panic when there is a little noise (or grain as I prefer to call it, from the old film days.)
Noise reduction has to be applied carefully, too many photos nowadays look like they are smeared with vaseline.
But noise in digital photos are several things. The worst is colour noise, but most raw developers have effective tools for removing it. What is left is a slightly grainy look which is almost impossible to remove without getting that "smudgy" look. As long as the grain is random, not in a unform pattern, it does not matter to me.
I have been having a look at the noise today on a few photos I took this morning with sharpening and noise reduction settings right down.. To me they look far more natural aside from there being next to no CR around white windows.

The grain / noise I can see in the darks is very much reminiscent of old film photos so none of the square shapes ya get with some noise... If you catch my drift. To see it you have to blow it right but nothing a well done bit of noise reduction in post couldn't fix.

Strangely, the photos with no dji sharpening applied look, to my eye better... It might be a placebo effect but when zoomed in straight lines look, for want of a better way of putting it less pixelated

I
 
I'm going to have to test it but I think added sharpness for close up shots while doing something like a roof inspection could be a good thing (where the straight lines are going to be a good amount of pixels wide / accross) and so can be blown up but for landscapes or images that are farther away which have lines that are not so many pixels across not so good.

I'm going to have to test my theory but I'll report back.
 
I'm just a noob at this so forgive me if I'm missing something or am just ignorant.

I would have thought that sharpening an image would reduce CA because I would assume that it would focus the different frequencies of light on to a smaller point.

Now it might well be me doing something wrong but, with my mini 3 Pro in 48mp mode, the sharpening seems to be exacerbating the issue.

It seems like the sharpening is exacerbating the issue and the noise reduction is just smudging the results...

Or am I imagining it?
Lightroom,DXO PURE RAW,and Topaz have great sharpening/denoise programs that work well.
 
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Just shoot RAW and edit yourself, it's always been the better choice if you have the time and want the best possible results from a camera.

Yes. I learned about this in the last year and haven't looked back. You have full control over what tools are used and how they are used. You have full control over the exposure IN POST! It allows you to make the decisions about your photo and how it is manipulated, not some algorithm. Lightroom has an "auto" button to make adjustments and it's actually a good starting point, but I find I tweak from there, especially with shots that involve the sky.
 
OK so I just did a little test and I was mistaken about one thing before... I thought I was saving in j+raw but apparently I was just saving in jpeg

So I did another test with j+raw at different sharpness and noise reduction settings.

All at 48mp

-2 shrp -2 NR
-2 shrp -1 NR
-0 shrp -0 NR

And at every setting the jpeg looked decent when zoomed in but the DNG was utter trash!!!

It looks like the style (sharpness and noise reduction) settings do nothing at all to raw. Can someone please tell me if that's normal and if so, what's the point of having the settings in the 1st place?

I'll have to wait until I can get back to my PC to see if I can get the same quality in post but I doubt it.

Would DJI do that deliberately to force people to buy a more expensive PRO drone to get higher res images that are usable in the context of larger prints?

Non of this makes sense to me
 
Can someone please tell me if that's normal
Yes, the point of RAW is to not bake in processing so you can do yours in post without irreversible "damage" having already been done by the camera.

if so, what's the point of having the settings in the 1st place?
For JPEGs....

the DNG was utter trash!!!
I'll have to wait until I can get back to my PC
It's unprocessed. You need to load it into RAW processing software like Lightroom or the others mentioned earlier to make proper use of it,

Would DJI do that deliberately to force people to buy a more expensive PRO drone to get higher res images that are usable in the context of larger prints?
No, it's just standard photography workflow. But obviously there are difference between models just like a $100 camera doesn't give the same results as a $10K one.
 
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Yes, the point of RAW is to not bake in processing so you can do yours in post without irreversible "damage" having already been done by the camera.


For JPEGs....



It's unprocessed. You need to load it into RAW processing software like Lightroom or the others mentioned earlier to make proper use of it,


No, it's just standard photography workflow. But obviously there are difference between models just like a $100 camera doesn't give the same results as a $10K one
 
Yes. I learned about this in the last year and haven't looked back. You have full control over what tools are used and how they are used. You have full control over the exposure IN POST! It allows you to make the decisions about your photo and how it is manipulated, not some algorithm. Lightroom has an "auto" button to make adjustments and it's actually a good starting point, but I find I tweak from there, especially with shots that involve the sky.
The first slider I often use in Lightroom when editing raw is the clarity slider.Makes a world of difference.Many do exposure correction 1st if needed.
 
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Seems a reply might be missing above... but yeah, while photography got a LOT easier in the past 20 years there are still things to learn to get high quality results, even if they're very different than in the analog days and can now be experimented with quickly and "for free". If you've been at this for a while it's pretty impressive sometimes to go back to 15 year old RAWs and reprocess them with what you've learned since.
 
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Seems a reply might be missing above... but yeah, while photography got a LOT easier in the past 20 years there are still things to learn to get high quality results, even if they're very different than in the analog days and can now be experimented with quickly and "for free". If you've been at this for a while it's pretty impressive sometimes to go back to 15 year old RAWs and reprocess them with what you've learned since.
What's even more impressive is the results some photographers got without digital images and processing...
 
What's even more impressive is the results some photographers got without digital images and processing...
Even more remarkable is how many of the top end film photographers were ecstatic to be able to do their edit in digital after scanning their film instead of long hours in the darkroom to edit their work.

I originally felt guilty about doing digital edits a couple of decades ago when I first dropped film for digital until I started reading comments from the photographers I admired. Almost every single one of them was touching up their images in the darkroom before you saw prints of their work.

The notion that fine art photography came straight out of the camera is delusional at best. For the record I have been doing landscape photography for over 60 years now.
 
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What's even more impressive is the results some photographers got without digital images and processing...
Plate and later on film photographers spent many hours in darkrooms using techniques such as dodging and burning to enhance and improve their shots, editing in post is almost as old as photography itself.
From experience, I'd recommend leaving the sharpening and NR sliders at the default. They'll only affect the JPG anyway. Cleaning up chrom. abb. With Lr (or any other RAW editor) will also attack other brightly coloured elements in your shot. If you shoot a busy road: take a close look at blue/red/green vehicles or signage in contrasty primary colours.
For effective noise reduction: edit RAW's. Lightroom isn't the only option, there are open source pro quality RAW editors such as DARKROOM that really give the Adobe option a run for its money. The one mentioned has a module titled 'astrophoto denoise' which specifically targets sensor noise but leaves linear and edge detail crisp. If you're interested, I'm happy to upload a 'before & after' shot to illustrate. The same software handles chrom. abb. very well too and the real bonus with DARKROOM is that you don't pay a monthly fee to use a pro-grade set of tools.
 
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