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Ninja1283
03-19-2011, 09:34 PM
I shoot in RAW, and use DPP for the majority of my PP then Photoshop if needed, and was wondering the best way to incorporate barrel distortion correction into my work-flow. I currently use PT lens, and really like the simplicity, but it seems like a lot of work if I just need to correct for barrel distortion in PS: PP in DPP, export as TIFF, open in PS, use the PT lens plug in to correct for barrel distortion, reopen in DPP, and finally export as JPG.


I currently shoot quite a bit with my 15-85mm f/3.5-5.6, and am looking at the 10-22mm, so barrel distortion can get fairly noticeable at times. I would really would like some tips on streamlining my digital work-flow. Any suggestions?





Thanks!

tkerr
03-19-2011, 09:54 PM
Which version of Photoshop are you using?


I just open my RAW files into Adobe Camera RAW(ACR) and make any lens correction with that.


I can access my RAW files with Adobe Bridge which works seamlessly with both Photoshop and ACR, or I can open my RAW Files into ACR from Photoshop without using the Adobe Bridge. No need to convert my files to tiff or open multiple applications that don't work together seamlessly. I don't have to exit one application and then open another to re-open my image.


I don't even bother with DPP anymore. If you're going to be opening into Photoshop anyways why not just export/save it as a jpeg from there?

DavidEccleston
03-19-2011, 09:59 PM
DPP has a checkbox for lens distortion and vignette correction. Under the hood it's applying the fixes appropriate for lens used. If you use a 3rd party lens, then you'd need to use something else.


If you want to use Photoshop, I can understand if you use DPP first instead of Adobe Camera RAW, but I'm not sure why you don't use Photoshop to save as JPG. Loading back into DPP just to save seems like a lot of extra work for nothing. If all you're using Photoshop for is lens corrections, you might be able to just stick to DPP. Just for completeness, I'll point out Lightroom allows you to download or create your own lens profiles, and it seems fairly painless. Take a couple shots of provided patterns, have it analyse them, and voila, your own custom lens aberration profile.


To use DPPs fixes,


Click on the NR/Lens/ALO tab.
Click 'tune' on the Lens Aberration Correction section.
Turn on distortion to fix lens distortion.
Turn on peripheral illumination, if it's not already on (you can upload lens profiles to newer cameras and have it automatically applied) for vignette correction.

tkerr
03-19-2011, 10:28 PM
FYI, Aside from it already including profiles for many of the more common lenses, You can create your own lens correction profiles for ACR too; Since ACR 6.1.


On Edit:
IMHO, for most general photography, Lightroom is the best single application you can probably purchase. Probably the only application most people really need. It has all the necessary tools you will need and then some so you won't have to open and close multiple applications or convert to a different file format just to make adjustments. And if you want and have it, it also works seamlessly with Photoshop.

Ninja1283
03-19-2011, 10:56 PM
Which version of Photoshop are you using?


I have the CS4 suite, so I cannot access barrel distortion corrections direct from ACR 5.7. (I think the newer 6.1-6.2 versions of ACRthat allow barrel distortion correctionsrequire CS5.) Seems like the ideal solution, but PT lens has a nice PS filter plug in that works well if I stay in Photoshop.



If you're going to be opening into Photoshop anyways why not just export/save it as a jpeg from there?


I tried, but the TIFFs I usually work with from DPP are too big to directly save as a JPG for some reason.





I'm new to all this, and probably sound like an idiot, but thanks for the help so far.

neuroanatomist
03-19-2011, 11:04 PM
Personally, I find DxO to be the best RAW converter. It

neuroanatomist
03-19-2011, 11:13 PM
Ps. In the recent 15-85 vs. 18-200 thread, barrel distortion came up as well. I posted a DxO-corrected vs. uncorrected image there. I had planned to take a shot with the 24-105mm at 24mm (lots of barrel distortion there), vs. the TS-E 24mm (no distortion) of the same scene. This might be a better thread to post that...

Ninja1283
03-20-2011, 05:36 AM
Personally, I find DxO to be the best RAW converter. It's corrections for distortion and noise are better than DPP, and unlike ACR the corrections are based on quantitative testing of each specific camera+lens combo. Specifically for barrel distortion, DxO resulted in better correction and sharper corners in the corrected areas (posting from my iPhone so search doesn't work, but search for "mini bake-off" for my DPP vs. DxO comparison).


I'll have to give that article a read. I looked into DxO before, but couldn't justify the purchase at the time. Always thought it was more expensive, but I guess I must have been looking at the pro body elite version or something...

Fast Glass
03-20-2011, 06:02 AM
helpI use DXO and like Neuro said it's the best RAW converter out there. I shoot lot of high ISO images and DXO isextremely helpfulfor that.


John.

neuroanatomist
03-21-2011, 06:52 PM
Here are some test images showing barrel distortion and corrections. I had done something similar L IS, except for the bottom right image shot with a TS-E 24mm f/3.5<span style="color: #ff0000;"]L II. Both DPP and DxO do a good job correcting the barrel distortion of the zoom lens. DPP crops the corrected image a little bit tighter than DxO, such that the centers of the edges are the same in the uncorrected and DxO images. Interestingly, 24mm on the 24-105mm is a little bit wider than the 24mm TS-E framing. Click image for a larger view.


http://farm6.static.flickr.com/5030/5547075485_9e4f00fc9e_b.jpg (/photography_tips_techniques1/f/13/t/5120.aspx]previously, but in that case there was both barrel distortion and perspective distortion in the mix. IN this comparison, there's only barrel distortion. Apologies for the lack of inspiration in subject matter - I wanted to find something more interesting than this classic approach to showing barrel distortion, but I had limited time this morning as the snowflakes were starting to fall (silly me, I thought it was the first day of spring...).


Images were shot on a 5DII with the 24-105mm f/4<span style="color: #ff0000;)

HDNitehawk
03-21-2011, 06:55 PM
John


TS-E shot dead center with no tilt or correction right?

neuroanatomist
03-21-2011, 06:57 PM
Correct - no tilt or shift, and I had a bubble level in the hotshoe.

HDNitehawk
03-21-2011, 07:02 PM
I wonder how the 24mm F1.4L II would fair in this comparison. The TS-E it almost appears as none or very little. Sitting here with a ruller on the screen the TS-E still looks better to me than the corrected versions.

Mark Elberson
03-21-2011, 07:23 PM
Nice job John. I am honestly shocked by how bad that really is!


While you were shooting these did you take any with the lens tilting up? I'd be curious to see how much that statue would start to lean if you did. I bet at that point you'd really hear people complaining about the "barrel" distortion [:P]