Why I shoot raw

[eccles]

I shot this orange tip with my Sigma 400mm telemacro yesterday. It flew off before I could get close. It had gone, and the whites looked lost forever as well:

2008_04_17_orangetiporiginal.jpg (131.75 KiB) Viewed 925 times

But a bit of exposure correction with Photoshop showed the detail was still there in the blown whites. OK the subject was a bit small for an A4 print, but for web display it's not bad is it?

2008_04_17_orangetip.jpg (127.38 KiB) Viewed 924 times

[Chris]

Thats extraordinary Eccles... so would that info have been lost for ever if the file was converted to jpeg in camera?

[Gruditch]

I got a similar shot of an orange tip the other day, and like yours Eccles the whites blow out. I've had several goes at trying to make something of this shot, but have found that, although I can easily adjust the light and contrast to bring back the detail lost on the white areas, this tends to ruin the orange areas by dulling them. The only way I have found so far to get round this, is to select the orange areas and work on them separately. But as with your image it leaves a nasty overlap line, I'm sure your be grateful to me for pointing this out, as now everyone will notice. Well here's my best effort so far.

Gruditch

[Denise]

Oh good, it's not just me that has trouble with the white blowing out of proportion then. Phew that's a relief.

Denise

[eccles]

But as with your image it leaves a nasty overlap line]

Overlap line? I didn't do any selective correction, but just dialed back a -2 stop exposure correction over the whole image, which is why the background is dark in the corrected photo.
Edit: Looking again, I see what you're driving at, but it isn't overlap as I didn't apply any selective correction. I think it's just oversaturation of the orange colour near the white boundary, causing it to burn out. This can happen when applying -ve exposure correction. Photoshop can rescue that I think. I'll have another go at it tomorrow.
In answer to Chris's question, you can do some recovery from blown whites with in-camera produced jpegs but it's not as effective as doing it from the raw original. Other things like hidden shadow detail and chromatic aberration can be corrected more effectively as well.

[eccles]

I've worked out what has happened. When an image gets overexposed the RGB levels can lose their correct colour linearity as one colour oversaturates and clips before another. When pulling back the exposure in photoshop this resulted in a colour cast where the worst overexposure occurred, in this case on the orange/white boundaries, where the colour became a salmon pink instead of pale orange. There's a sort of grey boundary between the pink and white as well. I had another go at it but couldn't get it much better than the first attempt. About the best I can do is ease off the exposure correction to have the whites close to blowing out but still keep a bit of detail there. That way the pink boundary effect is less visible.

DSC07212mod.jpg (95.95 KiB) Viewed 808 times

[Dave McCormick]

Gruditch, I managed to make a better attempt at your pic:



I just decreased the brightness slightly and decreased the contrast slightly, just a little bit

[Pete Eeles]

Hi Dave - I have to say that I prefer the original. Yours looks way too dark on my (calibrated) monitor and the orange doesn't look particularly natural to me. Why do you think your adjustments are better - what do you think has improved?

Cheers,

- Pete

[Gruditch]

Yeah I'm sorry Dave, but I must agree with Pete, that's way to dark. And that is the same problem I was having, if you darken the whites to far you lose the orange.

Gruditch

[Dave McCormick]

yeah, suppose your right, I am still trying to work ok getting the WB right in shots anyway

[PeterD]

Hi all,

What you are doing in photoshop, in my opinion, would be better applied in-camera. With a white butterfly, as with white birds, it would be better to reduce the exposure using the compensation control when taking the shot. This will reduce the amount of PP work. Remember that, depending on your metering mode, the amount of reflected light from the scene is averaged yet the white is the brightest part of the image. Without compensation, you would be likely to over-expose the white and hence risk losing the detail.

Peter