Lens correction on every image?

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Name
Fraser
Edit My Images
Yes
Was away the weekend taking my a6500 and 18-105 f4 lens. Took a mixture of snap shots, landscapes, architecture and one thing which noticed is quite sever barrel distortion. I knew it was an issue with this lens but its never been overly noticeable.

Anyway, popped them all into dark table (light room for us cheapskates) and used the lens correction which instantly fixes it. This got me thinking about a couple of things.

  • With the image being skewed about, surely this would affect image quality quite drastically?
  • Do others do it automatically, or do they only do it on images which looks like it needs it?
I've tried to a/b it and I'm struggling to see any difference, quality wise, but I'm awful at pixel peeping. However I can't see how the IQ can't be affected. Also, although in some images (pretty much anything with no straight lines) I don't think it looks bad, then I switch it on and realise how distorted it was! Should I really be worrying about that? Obviously most folk won't get the chance to a/b images but to a more keen eye, would distortion be off putting?

I'll give some examples of what I mean, if there's any need, but I'd imagine you all have a good idea what I'm talking about!

The only reason I ask is simply because I might be doing things to my images in post which are not required and are only having a negative impact without me really noticing!

Thanks
 
My feeling is that if the barrel distortion is so bad it is worth putting up with some minor image degradation elsewhere to correct it. Lightroom does the same thing through its lens profiles and my Olympus does it completely automatically so you don't have a choice about it. Others opinions may differ!
 
Lenses are designed these days to fix thing optically where that is the best option, and fix others in software where that is the best compromise. overall this give the best result, notwithstanding the price point, Some corrections simply can not be made effectively with optical design alone, with out reducing the effectiveness of other corrections elsewhere.

Every stitched pan you make, is redrawn to give the Projection that you set, and no one ever seems to notice. This is much the same process as barrel distortion correction.
 
I only correct in post if makes a picture look wrong - a curved horizon or bowed verticals, for example. What you have to watch out for, and allow for when taking photos you expect will need correction, is the cropping of anything near the edge of the frame.
 
As I usually use the camera manufacturer's raw converter (where lens correction will generally be on by default and they'll have gone to a lot of trouble to make their own lenses look as good as possible), I suspect I never notice some of the aberrations they've fixed in software. Might be interesting to go back to the raw files and see what they 'really' look like.
 
The more mp the less effect on sharpness after transformation. At 20mp it is already barely noticeable but at 10 or less it's not so good.

I leave it on by default, and sometimes will turn it off if the image doesn't have clear geometry or shooting high quality primes with minimal distortion. Ca is always on.
 
, is the cropping of anything near the edge of the frame.

Sometimes it's very easy to generate the missing small pieces in Photoshop. Don't crop the image if you are just missing some corners of blue sky after transformation
 
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