Ad
Ad
Ad
Pages: [1] 2 3 »   Bottom of Page
Print
Author Topic: questions about exposure blending from one file  (Read 10783 times)
Marshallarts
Newbie
*
Offline Offline

Posts: 30


« on: August 11, 2009, 03:50:16 PM »
ReplyReply

I've been asking this question on DPReview here and have wasted days trying to understand my concern.  To quote Luminous Landscape Merge to HDR in Photoshop CS2: A First Look "A more contemporary approach is to take multiple exposures of the same scene, varying (usually) just the shutter speed. Take a "normal" exposure, and then a few more at 1-2 stops over and under that point. Then, in Photoshop, blend these exposures, using the parts from each one that capture properly the part of the scene that you want.This can work very well, but to look convincing it needs to be done with some considerable skill, and usually requires quite a bit of work with masks and brushes. My blending tutorial looks at this technique. Also popular, when multiple exposures aren't possible (for example when there is movement in the scene), is to process the RAW file twice, once for the highlights and once for the shadows. This can't, of course, extract information that isn't in the actual file, but it can do a better job than using the usual raw processing tools currently available. The same blending techniques as are used for merging multiple exposures are also used here, with similar issues arising."

I'm trying to understand why the usual raw processing tools can't do as decent a job, since after all the processed RAW files to be combined were created in the usual raw processor.  What makes the multiple processed raw files better when combined?  Should the usual raw tools know how to isolate the regions that need adjusting in a whole image?  I completely understand the principle of exposure blending.  My questions is more about what happens during usual processing that makes it so it's not as good of a way to do it.

Also, I've been using Photomatrix to create HDR from single raw images.  Does this automatically create the different exposures necessary?  I also use the program for true HDR photos from multiple exposures on location.  But I've never learned how to properly adjust single RAW images to prepare them for blending manually (not using Photomatrix).  Does one only adjust the exposure slider and not touch Blacks, recovery, or fill when making the separate exposures?

Also, when combining photos, especially in generating HDR from bracketed exposures, is it best to not adjust any other perimeters and save image editing to after it is fully created?  (except for exposing once for highlights and once for shadows in the single RAW file method)

Here is my first attempt at HDR from bracketed exposures (-2EV, 0, +2EV).  I know many people don't like this effect.  I'm working on making it look more natural.  But this was definitely a situation where dynamic range was very high.  I have another question for checking when is appropriate to use HDR since it's pointless when DR isn't high.  Looking at my histogram, if I'm still getting a lot on both the highlight edge and the shadow edge wouldn't that indicate bracketing and exposure blending is necessary if I want to include those lost regions to clipping?  thanks!
« Last Edit: August 11, 2009, 03:51:12 PM by Marshallarts » Logged
jjlphoto
Sr. Member
****
Offline Offline

Posts: 467


« Reply #1 on: August 11, 2009, 08:08:04 PM »
ReplyReply

True 32bit HDR has to come from more than one unique file, since one file has only 12~16bits depending on camera/back used. The same file processed two or three times with different parameters is still the same bits.
« Last Edit: August 11, 2009, 08:10:10 PM by jjlphoto » Logged

Thanks, John Luke

Member-ASMP
Eric Myrvaagnes
Sr. Member
****
Offline Offline

Posts: 8064



WWW
« Reply #2 on: August 11, 2009, 08:29:28 PM »
ReplyReply

Quote from: jjlphoto
True 32bit HDR has to come from more than one unique file, since one file has only 12~16bits depending on camera/back used. The same file processed two or three times with different parameters is still the same bits.

True, but it may be easier to adjust the high values and low values separately and then combine the two. This seems to be what Mark Segal is doing in today's (August 12, 2009) essay. What's New.

Read it and see if it answers any of your questions.
Logged

-Eric Myrvaagnes

http://myrvaagnes.com  Visit my website. New images each season.
Panopeeper
Sr. Member
****
Offline Offline

Posts: 1805


« Reply #3 on: August 11, 2009, 10:28:51 PM »
ReplyReply

Quote from: Marshallarts
I'm trying to understand why the usual raw processing tools can't do as decent a job, since after all the processed RAW files to be combined were created in the usual raw processor.  What makes the multiple processed raw files better when combined?  Should the usual raw tools know how to isolate the regions that need adjusting in a whole image?
How would the raw processor know what you want to achieve?

The problem with the single pass raw processing is often just what you pointed at: different parts of the image require different adjustments. How to develop which part may be straightforward, but it may be complicated, subject to taste, goal, scenery, etc.

I just finished a pano (I shot it for over two years ago in Zion and today was the time to process it). It is a difficult location because of the valley between the high mountains. If I develop the frames for the foliage, the rock illuminated directly by the sun gets blown (the red is particularly a problem). If I develop it for the rock, the trees are far too dark; see the attachments. So, I developed the same frames twice. Blending was simple: I loaded them as layers and added a vertically graduated mask to one of them. The result is Zion pano (the sky comes from different frames, which were exposed lower, but I did not use any HDR technique to put them together).

The blending can be much more complicated in other cases, it may require tone mapping as well.
« Last Edit: August 11, 2009, 10:30:08 PM by Panopeeper » Logged

Gabor
Marshallarts
Newbie
*
Offline Offline

Posts: 30


« Reply #4 on: August 11, 2009, 10:44:44 PM »
ReplyReply

Quote from: Panopeeper
The problem with the single pass raw processing is often just what you pointed at: different parts of the image require different adjustments.
Please forgive my misunderstanding.  This seems to hint at what people are missing in what I'm saying, maybe I'm the one confused.  You stated the examples between the rocks and trees and how you need to process for both which have different exposure values, and then blended them.  But isn't that the point with RAW processing, that one can distinguish between exposure values and manipulate them independently?  That I can raise my fill light in the case of the darker trees and independently adjust the exposure for the brighter rocks.  I understand that the results from multiple processing of a single image speaks for itself, but I'm finding it hard to understand how since it seems a RAW editor with specific perimeters for different portions of your EV exist (ie. Recovery, Exposure, Fill Light, Blacks).  What about processing multiple versions of a picture makes it better?
Logged
Marshallarts
Newbie
*
Offline Offline

Posts: 30


« Reply #5 on: August 11, 2009, 11:19:40 PM »
ReplyReply

Quote from: EricM
True, but it may be easier to adjust the high values and low values separately and then combine the two. This seems to be what Mark Segal is doing in today's (August 12, 2009) essay. What's New.
Excellent essay!!  Thanks!

Also, to jjlphoto, I hear what you're saying.  In my original thread at DPReview my questioning sparked a tirade about HDR and how from a single image you can't create anymore dynamic range than was originally captured--an insightful reminder but not relevant to my question.  Then came the comments about HDR looking fake and also how it's pointless to attempt HDR when your scene's dynamic range isn't high to begin with (if your scene is only 8 stops and within the dynamic range capable of your sensor).  Also a good reminder but sidestepping my questions.

Despite all the opinions people still continue to use these techniques and I'm always trying to understand the best methods to learn which techniques are most correct.  I've heard for awhile about people processing multiple versions of a single image in a form of HDR.  Truly this is not the same as multiple bracketed exposures so ignore the semantics.  Yes no additional DR is created but people still do this and call it what you will is still a form a dynamic range manipulation.  Many people don't like the way real HDR looks.  I'm interested in exploring this more myself.  I'm sure my photo looks very poor to someone with more HDR experience.  

Maybe I should attempt it with the single RAW image method described in the essay.  Is that typically how this method works--exposing for specific areas in the photo then blending them?  I think my confusion at first was how one goes about this versus the more common HDR methods of simply combining evenly bracketed photographer in HDR software.

Maybe a part of my confusion is in my approach to begin with.  Looking at a histogram if there are areas peaking/clipping on either side of my chart, I blindly assume bracketing my exposure will allow for those areas to be better exposed.  Honestly I never concerned myself with where in the image those areas are peaking.  Is this a poor way of deciding something requires HDR bracketing?
« Last Edit: August 11, 2009, 11:24:21 PM by Marshallarts » Logged
JeffKohn
Sr. Member
****
Offline Offline

Posts: 1671



WWW
« Reply #6 on: August 11, 2009, 11:49:50 PM »
ReplyReply

Quote from: Marshallarts
Please forgive my misunderstanding.  This seems to hint at what people are missing in what I'm saying, maybe I'm the one confused.  You stated the examples between the rocks and trees and how you need to process for both which have different exposure values, and then blended them.  But isn't that the point with RAW processing, that one can distinguish between exposure values and manipulate them independently?  That I can raise my fill light in the case of the darker trees and independently adjust the exposure for the brighter rocks.
The problem is that the controls in RAW converter are for the most part global to the whole image. Lightroom and ACR do have some localized edits, but they're pretty limited (for instance no fill light or recovery sliders, to use your example). What happens is that if you try to boost the shadows and recover the highlights in a single RAW conversion, you end up with a dull and lifeless image. A pleasing image needs contrast, both local and global, and if you just linearly compress a high-contrast scene to fit within a reduced dynamic range the result is pretty ugly.

By processing the image twice, you can get target your RAW conversions for specific areas of the image to get a more pleasing result.
Logged

Panopeeper
Sr. Member
****
Offline Offline

Posts: 1805


« Reply #7 on: August 11, 2009, 11:51:44 PM »
ReplyReply

Quote from: Marshallarts
You stated the examples between the rocks and trees and how you need to process for both which have different exposure values, and then blended them.  But isn't that the point with RAW processing, that one can distinguish between exposure values and manipulate them independently?
This is not always so straighforward. I can adjust the mapping in the raw conversion (fill light, recovery, curves, etc.), but that will effect the entire image. However, that is not working in the example I showed above: parts of the rocky areas are quite dark, and they are supposed to remain so. Lifting the foliage out of the shadows ruins the contrast on the rock surface.

ADDED:

I just see Jeff posted exactly what I wanted to answer. Sorry for the repetition, I was typing too slowly.
« Last Edit: August 11, 2009, 11:54:30 PM by Panopeeper » Logged

Gabor
NikoJorj
Sr. Member
****
Offline Offline

Posts: 1063


WWW
« Reply #8 on: August 12, 2009, 12:17:28 AM »
ReplyReply

Quote from: Marshallarts
I'm always trying to understand the best methods to learn which techniques are most correct.
The most correct technique is the one that gives the best image, period!  

In many cases, an efficient DR mitigation can be made from one raw exposure in LR/ACR, by the simple use of fill light/blacks (and to the expense of noise in the shadows).

However, if eg extensive highlight recovery is needed with the tone curve (as in the excellent Mark Segal's essay), then you hit the fact that the tone curve is not a "masking" tool (ie it affects all pixels of the image), and you have to rely on masking in PS or other pixel-level editing app (until LR's brush can do tone curve adjustments).
(edit : we've said the same thing 3 times, sorry for the echo)



Quote
Maybe I should attempt it with the single RAW image method described in the essay.

If shadow noise is not a crucial problem, one exposure at base ISO taken for the highlights often does the trick.
« Last Edit: August 12, 2009, 12:18:49 AM by NikoJorj » Logged

Nicolas from Grenoble
A small gallery
pegelli
Sr. Member
****
Offline Offline

Posts: 609



WWW
« Reply #9 on: August 12, 2009, 02:27:40 AM »
ReplyReply

To say it a fourth time, but different:

a pixel with for instance 50/50/50% R/G/B somewhere in the shadow area needs to move in a different direction (eg lighter) than another 50/50/50% pixel in the lighter area (eg. needs to become darker). A raw converter cannot do both in one pass since it only changes similar toned pixels in the same direction globally.
« Last Edit: August 12, 2009, 02:28:46 AM by pegelli » Logged

pieter, aka pegelli
NikoJorj
Sr. Member
****
Offline Offline

Posts: 1063


WWW
« Reply #10 on: August 12, 2009, 08:54:33 AM »
ReplyReply

Quote from: pegelli
a pixel with for instance 50/50/50% R/G/B somewhere in the shadow area needs to move in a different direction (eg lighter) than another 50/50/50% pixel in the lighter area (eg. needs to become darker). A raw converter cannot do both in one pass since it only changes similar toned pixels in the same direction globally.
That's a good description of the problem!

However (disclaimer : my answer only does cut hairs in quarters, as we say in French) keep in mind that some tools in some raw converters already do that based on the surroundings pixels : eg, Fill Light will probably lighten it if there are only darker pixels around, not if there are only lighter pixels.
There are already mask-based tools. The problem is when you hit their limit!
Logged

Nicolas from Grenoble
A small gallery
Guillermo Luijk
Sr. Member
****
Offline Offline

Posts: 1291



WWW
« Reply #11 on: August 12, 2009, 09:57:24 AM »
ReplyReply

Quote from: Marshallarts
I'm trying to understand why the usual raw processing tools can't do as decent a job, since after all the processed RAW files to be combined were created in the usual raw processor.  What makes the multiple processed raw files better when combined?  Should the usual raw tools know how to isolate the regions that need adjusting in a whole image?  I completely understand the principle of exposure blending.  My questions is more about what happens during usual processing that makes it so it's not as good of a way to do it.
It's a question of which software tool or method is more adequate to ease the task. The information contained in the RAW file (or files) is the same for all of them:
- A RAW developer with shadows/highlight and so forth sliders and options
- Two (or more versions) of the same RAW developed at different exposure values and manually blended in PS layers
- A specific tone mapping tool designed to enhance local contrast while reducing global contrast like Photomatix
...

Using 2 (or more) versions of the same RAW file developed at different exposures allows to easily obtain the desired result, and meanwhile there is no other clear winner option this will be one of the methods to use.

Let me show you a test I did some days ago to find out how well Photomatix can blend RAW files with a big exposure gap (4EV): it showed to be a total dissapointment!. A simple algorithm (implemented both in Zero Noise or through this simple tutorial in PS) consisting in selecting the pixels with the highest exposure performs much better than Photomatix's information blending:










If not even a specialized HDR blending software manages to achieve better results than a proper PS blending, why should we forget manual solutions and think a software tool should always be preferred?

Regards
« Last Edit: August 12, 2009, 10:00:12 AM by GLuijk » Logged

Mark D Segal
Contributor
Sr. Member
*
Offline Offline

Posts: 6968


WWW
« Reply #12 on: August 12, 2009, 07:23:13 PM »
ReplyReply

Quote from: Marshallarts
What about processing multiple versions of a picture makes it better?

My tutorial on this very topic was published on this site yesterday. It's not HDR but it works. How and to what extent would vary from image to image.

Mark
Logged

Mark D Segal (formerly MarkDS)
Author: "Scanning Workflows with SilverFast 8....." http://www.luminous-landscape.com/reviews/film/scanning_workflows_with_silverfast_8.shtml
Marshallarts
Newbie
*
Offline Offline

Posts: 30


« Reply #13 on: August 14, 2009, 12:29:19 AM »
ReplyReply

Wow!  I feel like I just got tutored by some real pros!  Thank you all for coming to the rescue.  Your answers really helped me better understand this.  They did raise some questions that I would like to independently ask.  It seems you all noticed you schooled me with the same answer but each way told was different.  This was helpful showing me different ways of explaining it in that I see a bigger picture, but I do have a few specifics I wouldn't mind cleared up.  
Quote from: JeffKohn
The problem is that the controls in RAW converter are for the most part global to the whole image. Lightroom and ACR do have some localized edits, but they're pretty limited (for instance no fill light or recovery sliders, to use your example). What happens is that if you try to boost the shadows and recover the highlights in a single RAW conversion, you end up with a dull and lifeless image. A pleasing image needs contrast, both local and global...
but LR does have fill light and recovery sliders...?  Perhaps you didn't mean to write "no" and was using fill light & recovery to explain your later explanation that when you adjust one you effect the other--making the image dull and lifeless.  This struck me like lighting as I finally realized how such global control would effect the curve.  Indeed we want to keep the contrast, and local control makes sense!

Quote from: Panopeeper
This is not always so straighforward. I can adjust the mapping in the raw conversion (fill light, recovery, curves, etc.), but that will effect the entire image. However, that is not working in the example I showed above: parts of the rocky areas are quite dark, and they are supposed to remain so. Lifting the foliage out of the shadows ruins the contrast on the rock surface.
another great explanation...  Then I wonder "when creating HDR (or WDR, let's not focus on HDR) how does it know which part of the scene is rock or foliage without complete manual control (ie. masking in photoshop)"..  This is partially answered by more great replies I will quote below but I'd like your take on it.  Unless it's part of a scene you can easily mask (i.e. the sky) how can you lift foliage that's mixed in with rocks you wish to stay the same?  Let me comment on the other replies that discuss this but your specific example seems particularly unique and difficult and I'd like your take on it.

Quote from: NikoJorj
...In many cases, an efficient DR mitigation can be made from one raw exposure in LR/ACR, by the simple use of fill light/blacks (and to the expense of noise in the shadows).
However, if eg extensive highlight recovery is needed with the tone curve (as in the excellent Mark Segal's essay), then you hit the fact that the tone curve is not a "masking" tool (ie it affects all pixels of the image), and you have to rely on masking in PS or other pixel-level editing app (until LR's brush can do tone curve adjustments)....

If shadow noise is not a crucial problem, one exposure at base ISO taken for the highlights often does the trick.
this is where I realized how by masking using 2 differently developed photos really makes sense.  And Mark's essay was a perfect example with that blown sky. I completely see how by recovering the sky you would also recover the building and loose contrast there.  But this is easy to mask as it's an isolated part of the scene.  In other cases the two could be mixed (like Panopeer's).

I know LR can do curve adjustments, what do you mean by LR's brush do tone curve adjustments?  Also I'm having trouble understanding your last sentence.  "...one exposure at base ISA.."  Do you mean process the RAW file bringing down exposure for the sky?  and how would that effect shadows?  or do you mean simply take the photo originally at base ISO unless you're worried about bringing up the shadows?  Could you please explain that?  (I didn't think you're talking about blending an HDR because we're talking about one exposure)


Quote from: pegelli
To say it a fourth time, but different:

a pixel with for instance 50/50/50% R/G/B somewhere in the shadow area needs to move in a different direction (eg lighter) than another 50/50/50% pixel in the lighter area (eg. needs to become darker). A raw converter cannot do both in one pass since it only changes similar toned pixels in the same direction globally.
Great explanation also.  But having two similarly shaded/colored pixels in two other regions would require the editor to know the difference between them.. Answered below but brings other questions.

Quote from: NikoJorj
That's a good description of the problem!   However... keep in mind that some tools in some raw converters already do that based on the surroundings pixels : eg, Fill Light will probably lighten it if there are only darker pixels around, not if there are only lighter pixels.
There are already mask-based tools. The problem is when you hit their limit!
I did not realize this!  How can I find out which program does this and what the limit is.  Essentially this could mean processing one version would be enough so long as these limits work for the image.  What are some mask-based tools I could learn about!

Quote from: GLuijk
It's a question of which software tool or method is more adequate to ease the task. The information contained in the RAW file (or files) is the same for all of them:
- A RAW developer with shadows/highlight and so forth sliders and options
- Two (or more versions) of the same RAW developed at different exposure values and manually blended in PS layers
- A specific tone mapping tool designed to enhance local contrast while reducing global contrast like Photomatix
...
Using 2 (or more) versions of the same RAW file developed at different exposures allows to easily obtain the desired result, and meanwhile there is no other clear winner option this will be one of the methods to use....
If not even a specialized HDR blending software manages to achieve better results than a proper PS blending, why should we forget manual solutions and think a software tool should always be preferred?
Great examples, thank you for sharing!  In fact after posting yesterday I spent more time better understanding Photomatix and learning that in generating HDR the choices in processing yield far different results.  Naively I thought HDR was one thing, as if a tool to be used globally.  Now I'm really seeing the bigger picture.  How in Photomatix you can go the tone compressor route or the details enhancer route.   But how you can also simply go the exposure blending route....and then the manual masking route like in Mark's essay.  I'd like to learn your method and will look at that tutorial.  Bottom line, it depends on how you want it to look.

If I've learned correctly, the tone mapping software route like Photomatix would be good in global situations where you want enhanced DR without flattening out the curve...!!   ding, ding, ding---is that correct!?  But in other situations where global adjustments are unwanted this may not be the correct route.  In those cases it seems manual blending (via masking) may be best..  

Under what situations have you learned each method should be used?

Quote from: MarkDS
My tutorial on this very topic was published on this site yesterday. It's not HDR but it works. How and to what extent would vary from image to image.

Mark
...and what an excellent essay it was!  Thank you so much for your tutorial!


I know this reply is long but I can't be more happy with any thread I've ever started!  This has really helped me a lot.  I really look forward to hearing back from my last questions!  Then I really think I'll have a well rounded understanding! (This is now my preferred forum!)
Logged
JeffKohn
Sr. Member
****
Offline Offline

Posts: 1671



WWW
« Reply #14 on: August 14, 2009, 12:41:36 AM »
ReplyReply

Quote
but LR does have fill light and recovery sliders...? Perhaps you didn't mean to write "no" and was using fill light & recovery to explain your later explanation that when you adjust one you effect the other--making the image dull and lifeless. This struck me like lighting as I finally realized how such global control would effect the curve. Indeed we want to keep the contrast, and local control makes sense!
It has them, but they're global. You can't limit the effect to just part of the image.
Logged

BernardLanguillier
Sr. Member
****
Offline Offline

Posts: 8182



WWW
« Reply #15 on: August 14, 2009, 02:14:58 AM »
ReplyReply

Quote from: JeffKohn
The problem is that the controls in RAW converter are for the most part global to the whole image. Lightroom and ACR do have some localized edits, but they're pretty limited (for instance no fill light or recovery sliders, to use your example).

Other than that, I find the highlight/shadow capability of C1 Pro to be doing the most convincing job at extracting detail from shadows without making the image look flat. I believe that their algo is not just global.

Globally, the simple answer to the original poster's question is that DSLR do in fact have too much DR for many scenes, and some form of tone mapping is required to map these informations to a small bit space like the one of our screens or papers. Most raw converters are poor tone mappers with the notable exception of those developped specifically for MF cameras (which explains why C1 Pro works so well on DSLRs as well).

Cheers,
Bernard
Logged

A few images online here!
Mark D Segal
Contributor
Sr. Member
*
Offline Offline

Posts: 6968


WWW
« Reply #16 on: August 14, 2009, 07:27:07 AM »
ReplyReply

Quote from: JeffKohn
It has them, but they're global. You can't limit the effect to just part of the image.

Jeff, yes you are correct thery are global, and it would be nice to see in a future release of LR/ACR that more of these controls become available under the Adjustment Brush, which as you know allows localized adjustment of tone and colour For now, we can use the Exposure, Brightness and Contrast controls and the brush density to achieve some of these effects locally - not ideal but still often quite useful.
Logged

Mark D Segal (formerly MarkDS)
Author: "Scanning Workflows with SilverFast 8....." http://www.luminous-landscape.com/reviews/film/scanning_workflows_with_silverfast_8.shtml
Mark D Segal
Contributor
Sr. Member
*
Offline Offline

Posts: 6968


WWW
« Reply #17 on: August 14, 2009, 07:28:45 AM »
ReplyReply

Quote from: BernardLanguillier
Other than that, I find the highlight/shadow capability of C1 Pro to be doing the most convincing job at extracting detail from shadows without making the image look flat. I believe that their algo is not just global.

Globally, the simple answer to the original poster's question is that DSLR do in fact have too much DR for many scenes, and some form of tone mapping is required to map these informations to a small bit space like the one of our screens or papers. Most raw converters are poor tone mappers with the notable exception of those developped specifically for MF cameras (which explains why C1 Pro works so well on DSLRs as well).

Cheers,
Bernard

Bernard, perhaps you meant that DSLRs do not have enough DR for many scenes.

Mark
Logged

Mark D Segal (formerly MarkDS)
Author: "Scanning Workflows with SilverFast 8....." http://www.luminous-landscape.com/reviews/film/scanning_workflows_with_silverfast_8.shtml
Guillermo Luijk
Sr. Member
****
Offline Offline

Posts: 1291



WWW
« Reply #18 on: August 14, 2009, 11:46:15 AM »
ReplyReply

Quote from: Marshallarts
If I've learned correctly, the tone mapping software route like Photomatix would be good in global situations where you want enhanced DR without flattening out the curve...!!   ding, ding, ding---is that correct!?  But in other situations where global adjustments are unwanted this may not be the correct route.  In those cases it seems manual blending (via masking) may be best..  

Under what situations have you learned each method should be used?

In my particular case I always use the same method: properly blend the captured information with pixel selection (ZN or the tutorial I linked which is basically the same), and then use curves with layer masks to manually tone map that information in PS.

The only automated software that I have found providing fairly good results (natural looking, no or very few unexpected artifacts) for HDR situations are the Enfuse/Tufuse implementations of this Exposure Fusion algorithm, and still it can't match a proper manual pp in PS.

I just did the Photomatix tests to find out how bad the software was at fusing the information fed into it. Photomatix's results depend strongly on how many images you provide, even if they are just copies of the same original RAW file with different exposure. From the point of view of information fusion, this is unacceptable.

Regards
« Last Edit: August 14, 2009, 11:49:23 AM by GLuijk » Logged

Peter_DL
Sr. Member
****
Offline Offline

Posts: 421


« Reply #19 on: August 15, 2009, 01:40:56 PM »
ReplyReply

Quote from: JeffKohn
It has them, but they're global. You can't limit the effect to just part of the image.
Probably a lack of controls (e.g. tonal width beside of strength).
Fill light as well as the Recovery slider seem to be selection based.
So strictly seen, the term “global” might be wrong, even though that’s what we see.

For me, Fill Light typically works well enough, whereas Recovery can be easily outperformed by “HDR blending”.
It’s not only a lack of controls, Recovery seems to be placed too late in the processing chain so that compression of highlight details and loss of color saturation beneath the upper shoulder of the usual tone curve applied can’t be restored or better prevented adequately.  Highlight details and colors which ARE in the Raw image are wasted. IMO.

The question of the threadopener is certainly valid – and should be addressed to the software engineers.

Peter

--
Logged
Pages: [1] 2 3 »   Top of Page
Print
Jump to:  

Ad
Ad
Ad