correction for barrel distortion

Martin_Moeck1 · January 17, 2006, 3:11pm

Assume you have a barrel distortion image like the one shown at

http://www.dcresource.com/reviews/nikon/coolpix5400-review/

towards the bottom of the page.

1) Are there software tools or algorithms available to correct these images before they are converted into an HDR image?

2) If not, is there a simple way to correct the HDR image for barrel distortion?

Martin Moeck

Kirk_Thibault · January 17, 2006, 5:03pm

Martin,

Photoshop CS2 has a Lens Correction filter that will help correct chromatic aberration, vignetting and barrel/pincushion distortion.

Lens Correction

However, I opened a HDR image (*.hdr) and the Filter>Distortion menu option was not available, leading me to believe that it will not operate directly on HDR 32 bit images. Thus, it would seem that you would apply it to your LDR sequence images before converting to a HDR image. The filter permits the applied settings to be saved, so you could open one image, applying the correction and then save the settings for the subsequent application to the rest of the image sequence, permitting automation in a batch action. If your sequence is taken with a tripod and the images are registered prior to correction, I would guess that applying the same correction through saved settings should displace the same pixels in each image and preserve image registration.

I just upgraded to CS2 so I haven't played with it yet.

kirk

···

On Jan 17, 2006, at 10:11 AM, Martin Moeck wrote:

Assume you have a barrel distortion image like the one shown at

http://www.dcresource.com/reviews/nikon/coolpix5400-review/

towards the bottom of the page.

1) Are there software tools or algorithms available to correct these images before they are converted into an HDR image?

2) If not, is there a simple way to correct the HDR image for barrel distortion?

Martin Moeck
_______________________________________________
Hdri mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/hdri

Fitzsimmons_Rob1 · January 17, 2006, 6:38pm

I could be wrong, but don't HDR creators need the original camera shot with
exif information? Doing Photoshop adjustments would lose that info. I'm
pretty sure Photosphere needs this, but I don't know if HDRShop does.

Rob F

···

-----Original Message-----
From: Kirk Thibault [mailto:[email protected]]
Sent: Tuesday, January 17, 2006 9:03 AM
To: [email protected]
Subject: Re: [Hdri] correction for barrel distortion

Martin,

Photoshop CS2 has a Lens Correction filter that will help correct chromatic
aberration, vignetting and barrel/pincushion distortion.

Lens Correction

However, I opened a HDR image (*.hdr) and the Filter>Distortion menu option
was not available, leading me to believe that it will not operate directly
on HDR 32 bit images. Thus, it would seem that you would apply it to your
LDR sequence images before converting to a HDR image. The filter permits
the applied settings to be saved, so you could open one image, applying the
correction and then save the settings for the subsequent application to the
rest of the image sequence, permitting automation in a batch action. If
your sequence is taken with a tripod and the images are registered prior to
correction, I would guess that applying the same correction through saved
settings should displace the same pixels in each image and preserve image
registration.

I just upgraded to CS2 so I haven't played with it yet.

kirk

On Jan 17, 2006, at 10:11 AM, Martin Moeck wrote:

Assume you have a barrel distortion image like the one shown at

http://www.dcresource.com/reviews/nikon/coolpix5400-review/
<http://www.dcresource.com/reviews/nikon/coolpix5400-review/>

towards the bottom of the page.

1) Are there software tools or algorithms available to correct these images
before they are converted into an HDR image?

2) If not, is there a simple way to correct the HDR image for barrel
distortion?

Martin Moeck
_______________________________________________
Hdri mailing list
[email protected] <http://www.radiance-online.org>
http://www.radiance-online.org/mailman/listinfo/hdri
<http://www.radiance-online.org/mailman/listinfo/hdri>

Kirk_Thibault · January 17, 2006, 7:58pm

Hi Rob - FWIW, I've never had a problem with Photoshop stripping this info - EXIF is kept intact. Good point to consider though.

···

------------------------------

Kirk L. Thibault, Ph.D.
[email protected]

p. 215.271.7720
f. 215.271.7740
c. 267.918.6908

skype. kirkthibault

On Jan 17, 2006, at 1:38 PM, Fitzsimmons, Rob wrote:

I could be wrong, but don't HDR creators need the original camera shot with exif information? Doing Photoshop adjustments would lose that info. I'm pretty sure Photosphere needs this, but I don't know if HDRShop does.

Rob F
-----Original Message-----
From: Kirk Thibault [mailto:[email protected]]
Sent: Tuesday, January 17, 2006 9:03 AM
To: [email protected]
Subject: Re: [Hdri] correction for barrel distortion

Martin,

Photoshop CS2 has a Lens Correction filter that will help correct chromatic aberration, vignetting and barrel/pincushion distortion. >>Lens Correction

However, I opened a HDR image (*.hdr) and the Filter>Distortion menu option was not available, leading me to believe that it will not operate directly on HDR 32 bit images. Thus, it would seem that you would apply it to your LDR sequence images before converting to a HDR image. The filter permits the applied settings to be saved, so you could open one image, applying the correction and then save the settings for the subsequent application to the rest of the image sequence, permitting automation in a batch action. If your sequence is taken with a tripod and the images are registered prior to correction, I would guess that applying the same correction through saved settings should displace the same pixels in each image and preserve image registration.

I just upgraded to CS2 so I haven't played with it yet.

kirk

On Jan 17, 2006, at 10:11 AM, Martin Moeck wrote:

Assume you have a barrel distortion image like the one shown at

http://www.dcresource.com/reviews/nikon/coolpix5400-review/

towards the bottom of the page.

1) Are there software tools or algorithms available to correct these images before they are converted into an HDR image?

2) If not, is there a simple way to correct the HDR image for barrel distortion?

Martin Moeck
_______________________________________________
Hdri mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/hdri

_______________________________________________
Hdri mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/hdri

Kirk_Thibault · January 17, 2006, 8:33pm

I suppose that if you alter the image, the EXIF info will be wiped.

···

------------------------------

Kirk L. Thibault, Ph.D.
[email protected]

p. 215.271.7720
f. 215.271.7740
c. 267.918.6908

skype. kirkthibault

On Jan 17, 2006, at 1:38 PM, Fitzsimmons, Rob wrote:

I could be wrong, but don't HDR creators need the original camera shot with exif information? Doing Photoshop adjustments would lose that info. I'm pretty sure Photosphere needs this, but I don't know if HDRShop does.

Rob F
-----Original Message-----
From: Kirk Thibault [mailto:[email protected]]
Sent: Tuesday, January 17, 2006 9:03 AM
To: [email protected]
Subject: Re: [Hdri] correction for barrel distortion

Martin,

Photoshop CS2 has a Lens Correction filter that will help correct chromatic aberration, vignetting and barrel/pincushion distortion. >>Lens Correction

However, I opened a HDR image (*.hdr) and the Filter>Distortion menu option was not available, leading me to believe that it will not operate directly on HDR 32 bit images. Thus, it would seem that you would apply it to your LDR sequence images before converting to a HDR image. The filter permits the applied settings to be saved, so you could open one image, applying the correction and then save the settings for the subsequent application to the rest of the image sequence, permitting automation in a batch action. If your sequence is taken with a tripod and the images are registered prior to correction, I would guess that applying the same correction through saved settings should displace the same pixels in each image and preserve image registration.

I just upgraded to CS2 so I haven't played with it yet.

kirk

On Jan 17, 2006, at 10:11 AM, Martin Moeck wrote:

Assume you have a barrel distortion image like the one shown at

http://www.dcresource.com/reviews/nikon/coolpix5400-review/

towards the bottom of the page.

1) Are there software tools or algorithms available to correct these images before they are converted into an HDR image?

2) If not, is there a simple way to correct the HDR image for barrel distortion?

Martin Moeck
_______________________________________________
Hdri mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/hdri

_______________________________________________
Hdri mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/hdri

Kirk_Thibault · January 17, 2006, 8:52pm

HDRShop will permit you to manually specify the exposure increment between each image in a LDR sequence.

···

------------------------------

Kirk L. Thibault, Ph.D.
[email protected]

p. 215.271.7720
f. 215.271.7740
c. 267.918.6908

skype. kirkthibault

On Jan 17, 2006, at 1:38 PM, Fitzsimmons, Rob wrote:

I could be wrong, but don't HDR creators need the original camera shot with exif information? Doing Photoshop adjustments would lose that info. I'm pretty sure Photosphere needs this, but I don't know if HDRShop does.

Rob F
-----Original Message-----
From: Kirk Thibault [mailto:[email protected]]
Sent: Tuesday, January 17, 2006 9:03 AM
To: [email protected]
Subject: Re: [Hdri] correction for barrel distortion

Martin,

Photoshop CS2 has a Lens Correction filter that will help correct chromatic aberration, vignetting and barrel/pincushion distortion. >>Lens Correction

However, I opened a HDR image (*.hdr) and the Filter>Distortion menu option was not available, leading me to believe that it will not operate directly on HDR 32 bit images. Thus, it would seem that you would apply it to your LDR sequence images before converting to a HDR image. The filter permits the applied settings to be saved, so you could open one image, applying the correction and then save the settings for the subsequent application to the rest of the image sequence, permitting automation in a batch action. If your sequence is taken with a tripod and the images are registered prior to correction, I would guess that applying the same correction through saved settings should displace the same pixels in each image and preserve image registration.

I just upgraded to CS2 so I haven't played with it yet.

kirk

On Jan 17, 2006, at 10:11 AM, Martin Moeck wrote:

Assume you have a barrel distortion image like the one shown at

http://www.dcresource.com/reviews/nikon/coolpix5400-review/

towards the bottom of the page.

1) Are there software tools or algorithms available to correct these images before they are converted into an HDR image?

2) If not, is there a simple way to correct the HDR image for barrel distortion?

Martin Moeck
_______________________________________________
Hdri mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/hdri

_______________________________________________
Hdri mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/hdri

Martin_Moeck1 · January 17, 2006, 9:40pm

No luck with Photoshop lens corrections. This is like poor freehand drawing. All gridlines are not vertical or horizontal, but warped in interesting ways.

Each square with barrel distortion has to be corrected individually. Greg needs to do take care of this right now This community needs a tool to shift pixels in a Radiance image around. Input could be a black and white grid image showing the barrel distortion. Output would be the image with straight lines.

Greg, I can help you with the command line :

pcomb -f barrel.cal barrelgrid.pic original.hdr > corrected.hdr

See, Greg, we are already halfway there

Martin

···

________________________________

From: [email protected] on behalf of Kirk Thibault
Sent: Tue 1/17/2006 3:52 PM
To: [email protected]
Subject: Re: [Hdri] correction for barrel distortion

HDRShop will permit you to manually specify the exposure increment between each image in a LDR sequence.

------------------------------

Kirk L. Thibault, Ph.D.
[email protected]

p. 215.271.7720
f. 215.271.7740
c. 267.918.6908

skype. kirkthibault

On Jan 17, 2006, at 1:38 PM, Fitzsimmons, Rob wrote:

  I could be wrong, but don't HDR creators need the original camera shot with exif information? Doing Photoshop adjustments would lose that info. I'm pretty sure Photosphere needs this, but I don't know if HDRShop does.

  Rob F

    -----Original Message-----
    From: Kirk Thibault [mailto:[email protected]]
    Sent: Tuesday, January 17, 2006 9:03 AM
    To: [email protected]
    Subject: Re: [Hdri] correction for barrel distortion

    Martin,

Photoshop CS2 has a Lens Correction filter that will help correct chromatic aberration, vignetting and barrel/pincushion distortion. Filter>Distortion>Lens Correction

However, I opened a HDR image (*.hdr) and the Filter>Distortion menu option was not available, leading me to believe that it will not operate directly on HDR 32 bit images. Thus, it would seem that you would apply it to your LDR sequence images before converting to a HDR image. The filter permits the applied settings to be saved, so you could open one image, applying the correction and then save the settings for the subsequent application to the rest of the image sequence, permitting automation in a batch action. If your sequence is taken with a tripod and the images are registered prior to correction, I would guess that applying the same correction through saved settings should displace the same pixels in each image and preserve image registration.

I just upgraded to CS2 so I haven't played with it yet.

kirk

On Jan 17, 2006, at 10:11 AM, Martin Moeck wrote:

      Assume you have a barrel distortion image like the one shown at

      http://www.dcresource.com/reviews/nikon/coolpix5400-review/

      towards the bottom of the page.

      1) Are there software tools or algorithms available to correct these images before they are converted into an HDR image?

      2) If not, is there a simple way to correct the HDR image for barrel distortion?

      Martin Moeck
      _______________________________________________
      Hdri mailing list
      [email protected]
      http://www.radiance-online.org/mailman/listinfo/hdri

  _______________________________________________
  Hdri mailing list
  [email protected]
  http://www.radiance-online.org/mailman/listinfo/hdri

Paul_LaBerge · January 17, 2006, 10:06pm

Has anyone tried "LensFix & PanoTools Plug-ins for OSX" ?
I haven't had much of a chance to try it but have heard good things about it.
I have a product description if that is of use.
Paul

···

No luck with Photoshop lens corrections. This is like poor freehand drawing. All gridlines are not vertical or horizontal, but warped in interesting ways.

Each square with barrel distortion has to be corrected individually. Greg needs to do take care of this right now This community needs a tool to shift pixels in a Radiance image around. Input could be a black and white grid image showing the barrel distortion. Output would be the image with straight lines.

Greg, I can help you with the command line :

pcomb -f barrel.cal barrelgrid.pic original.hdr > corrected.hdr

See, Greg, we are already halfway there

Martin

From: [email protected] on behalf of Kirk Thibault
Sent: Tue 1/17/2006 3:52 PM
To: [email protected]
Subject: Re: [Hdri] correction for barrel distortion

HDRShop will permit you to manually specify the exposure increment between each image in a LDR sequence.
------------------------------

Kirk L. Thibault, Ph.D.
[email protected]

p. 215.271.7720
f. 215.271.7740
c. 267.918.6908

skype. kirkthibault

On Jan 17, 2006, at 1:38 PM, Fitzsimmons, Rob wrote:

I could be wrong, but don't HDR creators need the original camera shot with exif information? Doing Photoshop adjustments would lose that info. I'm pretty sure Photosphere needs this, but I don't know if HDRShop does.

Rob F

-----Original Message-----
From: Kirk Thibault [mailto:[email protected]]
Sent: Tuesday, January 17, 2006 9:03 AM
To: [email protected]
Subject: Re: [Hdri] correction for barrel distortion

Martin,

Photoshop CS2 has a Lens Correction filter that will help correct chromatic aberration, vignetting and barrel/pincushion distortion. >>Lens Correction

However, I opened a HDR image (*.hdr) and the Filter>Distortion menu option was not available, leading me to believe that it will not operate directly on HDR 32 bit images. Thus, it would seem that you would apply it to your LDR sequence images before converting to a HDR image. The filter permits the applied settings to be saved, so you could open one image, applying the correction and then save the settings for the subsequent application to the rest of the image sequence, permitting automation in a batch action. If your sequence is taken with a tripod and the images are registered prior to correction, I would guess that applying the same correction through saved settings should displace the same pixels in each image and preserve image registration.

I just upgraded to CS2 so I haven't played with it yet.

kirk

On Jan 17, 2006, at 10:11 AM, Martin Moeck wrote:

Assume you have a barrel distortion image like the one shown at

http://www.dcresource.com/reviews/nikon/coolpix5400-review/

towards the bottom of the page.

1) Are there software tools or algorithms available to correct these images before they are converted into an HDR image?

2) If not, is there a simple way to correct the HDR image for barrel distortion?

Martin Moeck
_______________________________________________
Hdri mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/hdri_______________________________________________

Hdri mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/hdri_______________________________________________

Hdri mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/hdri

Greg_Ward · January 17, 2006, 10:11pm

Haha. Very funny, indeed!

I just tried the lens warp with Photoshop CS2 on my Mac, and it did preserve the Exif information, so I think that process could work.

Pcomb does support limited filtering, which could include some warping, but you have to keep the scans within 32 pixels of each other (or so), and that might be a problem. You would also want to implement a bicubic filter, I suppose.

-Greg

···

From: "Martin Moeck" <[email protected]>
Date: January 17, 2006 1:40:26 PM PST

No luck with Photoshop lens corrections. This is like poor freehand drawing. All gridlines are not vertical or horizontal, but warped in interesting ways.

Each square with barrel distortion has to be corrected individually. Greg needs to do take care of this right now This community needs a tool to shift pixels in a Radiance image around. Input could be a black and white grid image showing the barrel distortion. Output would be the image with straight lines.

Greg, I can help you with the command line :

pcomb -f barrel.cal barrelgrid.pic original.hdr > corrected.hdr

See, Greg, we are already halfway there

Martin

Axel_Jacobs · January 17, 2006, 11:15pm

The GIMP image manipulation package is available for OSX, and there are a
number of interesting plug-ins, including barrel distortion. Dunno if the
EXIF info is kept, but if not, you may just save it to a text file and
re-create an appropriate EXIF header once the dirty jobs are done.

There is also Hugin, a tool for stitiching panoramas. See here:
http://hugin.sourceforge.net/tutorials/perspective/en.shtml
how you can use it to correct barrel distortion. This is kinda
extreme-unbarrelling, though...

Axel

Axel_Jacobs · January 17, 2006, 11:17pm

..., and see down at the bottom of this page:

for more distortion correcting software. There is a Photoshop plug-in, too

Axel

Axel_Jacobs · January 17, 2006, 11:28pm

Sorry--link included now

..., and see down at the bottom of this page:

http://www.panotools.info/mediawiki/index.php?title=Lens_correction_model

for more distortion correcting software. There is a Photoshop plug-in, too

Axel

Axel_Jacobs · January 17, 2006, 11:29pm

Sorry--link included now

..., and see down at the bottom of this page:

http://www.panotools.info/mediawiki/index.php?title=Lens_correction_model

for more distortion correcting software. There is a Photoshop plug-in, too

Axel