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canoli
08-31-2009, 11:01 AM
The way I understand it, every RAW converter is different; they process files using different algorithms and therefore have various strengths and weaknesses. So far so good.


What I'm wondering is - which is the best one for retrieving highlights from RAW files? I read a post that said ACR (or was it DPP?) sets the HL point very low, and data that appears overexposed could be retrieved if run through a different RAW converter.


I ask because over the past week I shot a few thousand shots, many of which triggered the "blinkies" on my 40D. Are these HLs lost forever, or is there a RAW converter that will "see" that data better than ACR and DPP?


Hopefully I've asked this question clearly - looking to save some apparently overexposed shots, that's what it comes down to.


Any thoughts?


Thanks!

Bob
08-31-2009, 11:05 AM
If you have truly overexposed (saturated the 14 bit converter, etc.) then you cannot recoverthe data.

canoli
08-31-2009, 11:24 AM
right, I understand that. The thing is, everything I read tells me that both the blinkies and the in-camera histogram (which is generated from an on-the-fly conversion to a .jpg) are overly conservative. The articles I've read always imply there's more data than the histo shows - and more than the blinkies show.


The latest article alluding to this is in this month's Digital Photo Pro. Unfortunately the article doesn't specify which RAW converters are better than others...

Chuck Lee
08-31-2009, 11:50 AM
<span style="font-size: small; font-family: Times New Roman;"]canoli,


IMHO, ACR does a really good job at retrieving info above the jpeg cutoff line. The 40D at normal ISOs is good for +2-3ev most of the time.Unfortunately, sometimesthere is info that gets beyond the 14 bit capablility in which case the highlight recovery tool will pull that info to grey rather than white. This can cause gradient banding of the highlights which looks really bad. I'm sure you've seen this.


I have recently downloaded the new Pro version of SilkyPix Developement Studio ("http://www.shortcutinc.com/cms/index.php) and like the improvements they have made to the highlight recovery tool. I shoot with my 5D most of the time in which case I'm only able to pull down about 1 ev out of highlight land. I'll test the 40D soon enough. The thing I like is that the highlight tool compresses the upper end of the histogram without effecting the exposure of the mid tones or shadows. It's an effect you can readily see as you make the adjustment.


The program is available for 30 days once installed. You might find it worth checking out.

canoli
08-31-2009, 12:11 PM
Thanks Chuck - for the link and for sharing your experience.



The thing I like is that the highlight tool compresses the upper end of the histogram without effecting the exposure of the mid tones or shadows.


That's exactly what I'm looking for - going to give it a try later today.


Have you ever worked with DxO?

Chuck Lee
08-31-2009, 01:36 PM
Have you ever worked with DxO?


Yes.......


You can get some amazing results, but I found the interface very non-intuitive and it just didn't have the control I was looking for. It's a "if we have your camera and lense combination in our database" then guess what...... your're in luck!! It is possible that I didn't spend enough time with it but that's my simple take.


Bibble is another one you should check out if Silkypix can't get it done.


One important note about SilkyPix. There is a forum at shortcut inc. if you need more explanation of what some particular feature does. The English manual is still lacking a whole lot of specifics. You have to play around some to figure out what some things do best. I sort of treat it like a "work in progress" Silkypix gives you a huge amount of control so there is quite a bit to absorb. Once you understand the basic workflow, the process is very intuative and efficient. It, from what I hear, is similar to Lightroom.(which uses the ACR engine) The best thing to do is try the best you can to read through the manual ("file:///C:/Program%20Files/ISL/SILKYPIX%20Developer%20Studio%20Pro%20English/manual/man0002.html#_Anchor0.2.1). The biggest complaint about this sotware is the English translation of the manual.It took me about 2 weeks to get really proficient.

Daniel Browning
08-31-2009, 01:53 PM
What I'm wondering is - which is the best one for retrieving highlights from RAW files?


If the highlights are blown in one color (e.g. red), some raw converters will try to guess what would have been there from the surrounding blue and green pixels. The first raw converter to do that was Bibble, but when Adobe added that feature, they did a better job. To me, Adobe's guessing algorithm does a better job with blown red on skin tones.






I read a post that said ACR (or was it DPP?) sets the HL point very low, and data that appears overexposed could be retrieved if run through a different RAW converter.


You might be referring to when I said that DPP sets the wrong white point for some ISO settings, clipping up to 1/3 stop of highlight data.


Adobe has a problem where they apply a hidden "push" to raw files. The 5D2 has a hidden +0.33 EC, even when the EC slider is set to 0. You have you set the EC slider to -0.33 to see the highlights that Adobe is blowing by doing that. (The reason Adobe does it is to form the illusion that images from camera to camera are consistent, rather than show the reality that some camera raw files are darker and some are lighter.)



I ask because over the past week I shot a few thousand shots, many of which triggered the "blinkies" on my 40D. Are these HLs lost forever, or is there a RAW converter that will "see" that data better than ACR and DPP?


It depends. The histogram and blinkies on the camera LCD can be very different from the histogram and blinkies of the actual raw data. (If you want to see that, open the file in the free Rawnalyze (http://www.cryptobola.com/PhotoBola/Rawnalyze.htm) program.)


So if the data is not actually clipped in the raw file, then any raw converter will be able to render them. For speed and ease of use I prefer Lightroom. Two high quality free converters are RPP and RawTherapee.

canoli
08-31-2009, 02:16 PM
Ya, I see what you mean about the translation - their "More Info" page has a few ...interesting... phrases; but the intent is clear.


Any idea - under Supported Cameras - "40D * 8" - what that asterisk (or multiplication symbol?) and the 8 means? prob something simple but I can't figure it out. Other cams have similar notations...


thanks again - RTFM is always good advice, but bad translations can make it mighty tedious sometimes. I'll see how it goes...!

Chuck Lee
08-31-2009, 03:40 PM
Any idea - under Supported Cameras - "40D * 8" - what that asterisk (or multiplication symbol?) and the 8 means?


I would say someone left out the foot notes. That's what they look like.


Example


1) the dodge feature only works on this modelwhen it's taken an a cloudy Teusday afternoon.


2) the auto exposure feature is not available for this model


3) if you own this model your mother is a hamster and your father smells of Elderberries.


LOL.........[:D]

Chuck Lee
08-31-2009, 03:54 PM
Here is an "earlybird" version of the SilkyPix Pro manual ("http://www.mediafire.com/download.php?ztymi5yjedy) in English. Roberto says the index is missing. It should be fixed in a few days.

Keith B
08-31-2009, 04:10 PM
I have a very laymen comment:


I have processed identical RAW files with ACR and Aperture and Aperture flat out blew away ACR as far as highlights go. I have been absolutely amazed at Aperture's ability to bring back detail in blown out areas.


If you are on a PC sorry to have wasted your time.

canoli
09-01-2009, 02:41 PM
You might be referring to when I said that DPP sets the wrong white point for some ISO settings, clipping up to 1/3 stop of highlight data.


yep, that was it. Is that, in effect, doing what I said - showing overexposed HLs when they're not really overexposed? You mentioned the 5DII and its "hidden" extra +0.33 EC; I assume the rest of the cams have similar latitudes that are hidden...? How do you find that information?


thanks for the Rawnalyze link - looks like a pretty steep learning curve for me, but I'd love to learn enough to see the RAW data histograms as opposed to the camera's processed histogram. I think I'm seeing that simply by choosing the Histogram mode...the Mapped and Fine subsections are a little confusing to me right now, but I'll get it eventually I'm sure...


Do they have a user forum over there? I didn't find it if there is.


I'm hoping I can determine just how conservative my camera's blinkies really are. I think that would be helpful, provided of course that I'm using a RAW converter that can retrieve those blinkie HLs. From what you said, it sounds like all of them can do that.


Do you agree this would be an important bit of knowledge to have in the field?


Thanks again!

canoli
09-01-2009, 03:00 PM
thanks Keith - I agree, I've been very impressed with Aperture overall - robust editing features, friendly GUI, etc. Unfortunately I'm a PC user 90% of the time, so Aperture isn't available to me very often.


one of these years maybe I'll make the leap to Mac...

Daniel Browning
09-02-2009, 12:45 AM
Is that, in effect, doing what I said - showing overexposed HLs when they're not really overexposed?


Yes. It's a pretty minor effect, IMHO, but the idea of losing any highlights (even a small amount) just annoys me.



You mentioned the 5DII and its "hidden" extra +0.33 EC; I assume the rest of the cams have similar latitudes that are hidden...?


Yes, Adobe adjusts the profiles for all cameras to make it look as if they are the same. Some it's +0.33, others it's -0.33.



How do you find that information?


You can use the DNG profile editor, it's a free beta from their R&amp;D site.



thanks for the Rawnalyze link - looks like a pretty steep learning curve for me, but I'd love to learn enough to see the RAW data histograms as opposed to the camera's processed histogram.





You'll pick it up very fast; there's nothing to it.






I think I'm seeing that simply by choosing the Histogram mode...





Yep!



Do they have a user forum over there? I didn't find it if there is.


No forum. The creator posts on luminous landscape forums as "Panopeeper", you can probably get help there.



Do you agree this would be an important bit of knowledge to have in the field?


Yes!

canoli
09-02-2009, 01:33 PM
You'll pick it up very fast; there's nothing to it.


Ha! Thanks for the vote of confidence, but quite frankly the user's guide begins at a level I'm not sure I'm up to yet. But I'll go over to the LL website, see if I can find some help there - thanks for the suggestion.


One thing though, do you know what the Adj checkbox is for? I haven't been able to make it "do" anything, and I haven't found any reference to it in the user's guide - so far anyway. I'm using version 2.9.9.9


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Daniel Browning
09-02-2009, 05:38 PM
One thing though, do you know what the Adj checkbox is for?


It doesn't affect the visual image, it just makes certain numbers easier to read and compare.


Normally, the raw numbers displayed by Rawnalyze are the exact same ones that are in the raw file. (If you draw a red rectangle around some part of the image with the right mouse button, you'll see the numbers I'm talking about.) That's good because most of the time we want to see the *actual* numbers


But these can be difficult to compare between different cameras because they have different bit depth (12-bit vs. 14-bit) or black points. That's where the "Adj" checkbox come in: it maps the values to 8-bits (which most of us are used to seeing anyway) and puts 0 at the black point and 255 at the white point.

canoli
09-07-2009, 09:06 PM
ah! thank you, that makes perfect sense.