# A RAW conversion lesson



## ScanMan (Sep 11, 2007)

Just got back from a road trip through the Carolinas and snapped about 700-800 with a new Canon S90 P&S. Fantastic little shooter, blah, blah blah. 

Shot it all in RAW and when I loaded it up into LR last night, I completely freaked. ACR 5.5 doesn't support it yet (the menu says "beta"), but nonetheless, I saved my originals and then made DNG copies to start fiddling around.

The panicky part is when I checked a few shots of some framed paintings I'd taken in an art gallery...the geometric distortion was unreal. It looked like I was shooting with a fish eye. They looked good on the camera back, which i believe is a jpeg thumbnail of the RAW shot, but what a disaster on screen! 

I took a couple of shots just now in my office (one jpeg, one RAW) to compare. This really surprised me, as I had no idea that ACR would also compensate for the lens dynamics of each particular P&S.

So now I'm sitting on my thumbs waiting for ACR 6 or whatever, and considering using the Canon converter supplied on disc with the unit.

Always something to learn...


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## ScanMan (Sep 11, 2007)

Perhaps of interest to others...useful to me. Reichmann addresses the trend toward digital compensation for Barrel Distortion in P&S cameras, near the bottom of his S90 review.

Canon PowerShot S90


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## bsenka (Jan 27, 2009)

Very interesting. We're getting increasingly more RAW files from customers and while it is a bit of a PITA to work with, so far I've yet to encounter this barrel effect. I'll be watching for it now, that's for sure!


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## Guest (Dec 2, 2009)

I think there's S90 support in the LR 2.6 beta (and matching ACR update). They've been slow on adding new camera support presumably due to the LR3 beta sucking up all the devs time. I've been waiting for proper 7D support as well .. but I HATE the Canon tools they provide and try to avoid installing them on my machines whenever possible...

That's some pretty nasty barrel distortion! Eeeek!


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## Guest (Dec 2, 2009)

Yep, and it's in RC now, so it shouldn't be long. Was still in beta when I checked last week.

Lightroom 2.6 - Adobe Labs


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## ScanMan (Sep 11, 2007)

mguertin said:


> Yep, and it's in RC now...


Thanks for the heads-up! I'll be putting this to the test quite shortly. Here's a blurb from Ken Rockwell's new G11 review.

(edit) Agreed re the supplied Canon software!


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## ScanMan (Sep 11, 2007)

Ahhh, THAT'S better! 

RAW through LR 2.6 RC, with very little lens correction in PS. Not a great shot, just that it looks like things are going to straighten up and fly right. Thanks again.


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## Guest (Dec 8, 2009)

I might have to download it this week if they don't release the final version .. have a whole bunch of 7D shots that I have to process and have been waiting eagerly :/


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## ScanMan (Sep 11, 2007)

mguertin said:


> I might have to download it this week if they don't release the final version ..


From what I'd gleaned prior to installation, 2.6 was supposed to install as a separate application, which would run by itself and provide access to your original catalogues. This was great, I figured, since if 2.6 bombed, I could cut and run.

Instead, 2.6 merely installed over 2.5. No two LR scenario, but thankfully no issues so far. I think it's worth a go, mguertin.


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## eMacMan (Nov 27, 2006)

Barrel distortion is not unique to RAW images. It is an inherent effect of the Barlow lens design. Generally it is most likely to show up at the widest zoom and only on objects less than 10 feet away. Keeping the camera plane perfectly vertical will help to reduce the effect. I would expect major manufacturers to come up with built-in software corrections in the not too distant future.

My Olympus camera was bad, the Canon a bit better. The Panasonic I tried had almost no barrel distortion but did have some real soft spots. 

The Kodak I just purchased is really quite good but even so I have seen this problem on one or two images. Overall I am quite impressed considering that it is a 10:1 zoom. Image colour and density are not as accurate as I would like but easily corrected.


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