Lens Profile Corrections/ Chromatic Aberration Options

[Hugh Brown]

When outputting TIFFs from ACR for ingesting into PT Gui should I:

1. Check the "Enable lens profile corrections" option; and/or
2. Check the "Remove Chromatic Aberration" option?

If so, why?  If not, why not?

How do the checking/rejection of these options impact on the quality of the stitch or the process down the line?

Any help appreciated.  I'm hearing different things...

[Philip Chong]

For me only, and its only me, I did all of this in my favorite editor, ie doing lens profile corrections, denoise, sharpen, and doing PF/CA, tone mapping which I never do, any edits, etc etc.

I save it as 16 bit TIFF and I pass it to PTGui and do the stitching as PTGui is great for that only.  PTGui is not a photo editor.

[P.vR]

What I have been doing successfully with dozens of panoramas:

- CA: yes, in Lightroom or your favorite program.
- Lens Correction: don't use it. Let PTGui do its thing. It's even worse, the times i forgot I had Lens Correction on during import, PTGui wasn't very happy with my pictures at all.

I use a 16mm fisheye lens for my panos, and once Lightroom "corrected" those, there's not much left of the image anyhow.

Not sure if that would be the case for rectilinear lenses as well, but I just switch Lens Correction off, also for the odd time i use my 14-24mm lens for panos.

So, besides the CA in Lightroom, the only thing I sometimes do before the 16bits TIFF export, is to set the white balance for all images to something identical for the unusual time i had it on auto in my camera.

Oh, and correct portrait/landscape for some stubborn nadir shots.

(Yes, I know, some people prefer to switch auto-rotate off, but I don't. :-) )  

Just my 2 cents.

Peter

[PTGui Support]

The problem with lens correction happens when the lens is mounted
off-center. Since sensor pixels are only micrometers in size, this is
usually the case. PTGui can take this into account when applying lens
correction because it sees multiple overlapping images and it will
optimize to find the true optical center of the lens.

A raw converter would apply lens correction to the wrong center. This
will look fine in a single image but it will give stitching errors when
overlapping images are stitched. So it's best to leave this to PTGui.

Kind regards,

Joost Nieuwenhuijse
www.ptgui.com

> 1. Check the "Enable lens profile corrections" option; and/or
> 2. Check the "Remove Chromatic Aberration" option?

>
> If so, why?  If not, why not?
>
> How do the checking/rejection of these options impact on the
> quality of the stitch or the process down the line?
>
> Any help appreciated.  I'm hearing different things...
>

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[Hugh Brown]

Good answer.  Thanks Joost.

Is it also possible that these double lens corrections - being in likely conflict if ACR is applied - could lead to warping of the stars, etc around the extremities of the images?