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Old May 20, 2004, 1:28 PM   #1
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I know people talk about how you can save underexposed pictures with RAW in ways that you can't with levels or other simpler PhotoShop tricks. I've heard this enough that I believe it. But I got to see it in black & white today when converting a rather under exposed picture of a red-tailed hawk.

I posted 4 different pictures to this web address:

http://www.marx7.org/~esmith/galleries/raw_hawk_test/

The order of pictures is as listed in their file names. But they are:
  1. original [/*]
  2. embedded jpg with levels [/*]
  3. RAW converted and then levels [/*]
  4. RAW converted with exposure slider used.[/*]
My order of operation was to create number 4, giving it as much added exposure as was reasonable to me. It doesn't look great, but I'm not unhappy considering where I started from (I have other much better picture of this bird.) Then I made all the other pictures by trying to match the white of the hawk's breast feathers back to the RAW+exposure version.

First off, the jpg just fell down. That is clearly worse. I will note that it looks like it is slightly darker than the RAW starting out, so this isn't exactly a fair comparison, but its very close so I don't think it hurts it much. That color cast is annoying and I tried correcting for it with eye droppers and failed. Maybe Color Mechanic could do it, or someone else knows a way. I don't.

The two RAW converted images are similar. But if you look in the highlight to the right of the hawk, you can see a difference. The transition from sky to leaves happens quicker and with less transition in the RAW+levels one compared to the RAW+exposure. There is a bit of branch that is lost in the levels version.

The light spot over her head (its a female red tail) has color fringing on bottom part that isn't in the RAW+exposure version.

There are other differences (the hot spots seem whiter in the levels version.)

So for me, this is the final confirmation that I should never go back to JPG. I hadn't really planned on it, but now I won't even consider it. This shows that in the tough situations I often find myself in with bird photography, RAW will let me recover things that jpg can't. And the exposure slider is a better way to recover dark picture than levels.

Eric
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Old May 21, 2004, 6:51 AM   #2
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Eric,

Most of usagree that using the raw option gives much more flexibility than using jpeg. The issues are size and workflow. Whenever I'm shooting I often switch between the modes. For example in a wedding or baby christening, I'll shoot raw in the church and out in daylight I switch to jpeg. Same thing if I'm on vacation shooting wild life in challenging lighting. RAW is the way to go. Color balancing is another major advantage in using raw. That's the major advantage indoor photographers have whenshooting rawverses jpeg.

At some point we each decide that the quality of our photos demand the best (raw). Right now I'm shooting 50/50 raw verses jpeg. The flexibility of the 10D makes this possible. Thanks for sharing your findings.

Bill
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Old May 21, 2004, 11:38 AM   #3
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Just thought I'd throw my non-pro photographer/graphics pro in here. Not knocking RAW at all, but wanted to show that you can get nice results with just a JPEG. I think my version is a good example of saving the highlights and opening up the subject. The color cast was tougher. Ultimately, you'd need to do more adjusting in selected areas.

There's probably more noise in mine since I recompressed a JPEG. Wow, I just checked this image in preview mode and it really lightened it up too much, but you get the idea.




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Old May 21, 2004, 11:45 AM   #4
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RAW is definetely helpful....but were the leaves that color that day? they seem a little too light...

i would probably shoot RAW if it weren't for the fact that i don't have much memory...i only have 1 128mb card...so until i get a bigger one, i'm sticking with Jpeg.....it is easier to get on the internet too....wait...a question just popped into my head,

can you direct print a RAW file? like from camera to printer?
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Old May 21, 2004, 11:48 AM   #5
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The color and exposure got a little screwy when I posted it this forum. Not sure why.

--Alex
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Old May 22, 2004, 3:56 PM   #6
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Maybe something like this? Some OOF leaves or something on the limb, but a nice hawk and a good example of how RAW can recover.



Lin
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Old May 23, 2004, 10:49 PM   #7
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It was a very bright morning... but the leaves were probably not as light as the final (forth) version. My goal wasn't accuracy of the original scene, but a close to reasonably exposed hawk (not what was there, but what I wanted to see.) It looks like Lin did some sharpening on the hawk (whichI didn't do, I don't consider my shots "final" because all I did was play with exposure.)

Lin, you are right, there are some OOF branches/leaves in front of the hawk.

Alex Campuzano, what did you do to correct the color cast? Did you really take the original RAW converted image (#1) and turn it into what you made? I am certainly not a PhotoShop Expert (not by a long shot) so I'd be interested in what you did. I was just suprised how much easier it was to save that picture using the PS CS RAW converter & its exposure setting that using levels.

Eric
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Old May 23, 2004, 11:17 PM   #8
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HiEric,

I just took your original (first image) and adjused levels paying primary attention only to the subject to get the hawk's maximum dynamic range detail then did a select all, copy,and pasted the selection over the original and erased the selection except for the perch and hawk. Then I flattened the image and tested the hawk and found a one pixel out of focus blur and corrected it with deconvolution software which effectively sharpened it. It was a very quick and "dirty" job, certainly not as much attention to detail as I would invest with a full sized image, but enough to show that your are absolutely right about the advantages of shooting in RAW.

The RAW capture, even though it was badly underexposed because of the bright backdrop (spot metering would have helped) captured sufficient information to allow recovering shadow detail which would have been lost in a jpg capture. Once the RAW is converted to jpg, much of the captured dynamic range is preserved which differentiates a RAW filecapture from a jpg conversion by the camera.

Best regards,

Lin
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