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Old Feb 13, 2010, 9:11 PM   #11
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Dont need to prove you or anybody wrong. The only portion of high contrast in your tiff is the sky. The rest of the pick is uniform. Not a good pick for hdr! Now, if you use layers and a lot of processing, of course you can challenge Photomatix or any other program. Walter-S's night shots were extreme and interesting picks for hdr as well as a lot of vvcarpio's city shots. Go try PS with one of those picks and i'll believe Photomatix is not a useful program.
The three layer PS image has far more shadow detail than the Photomatrix version. As far as highlights go, the results are mixed - Some are better with PS, some better with photomatrix. The addition of gray to the sky is meaningless. Moreover, the PS version took one tenth of the time. If I wanted to, I could easily tweak it to be better, and Still save time over the Photomatirx version.

You wrote:
"Dont need to prove you or anybody wrong."

Well then, why are you posting at all?

As I said, I posted a link to the original RAW shot, if you're not prepared to prove me wrong, then you shouldn't make such flat out (and obviously incorrect) statments. I don't say this to be offensive. I say it because it's a simple statment of fact.

Again, the 100 percent crops for direct comparison:

Photomatrix:



Three layer Photoshop:




A simple glance will show you that the three layer PS version has more detail than the Photomatix shot, and the highlights are comparable.

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Old Feb 13, 2010, 9:43 PM   #12
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As you like it.
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Old Feb 13, 2010, 9:45 PM   #13
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Chato, you said you processed the picture in your "normal" way, leaving out one step. Either the original was a shot that didn't need HDR in the first place or your "normal" processing before Photoshop and/or HDR involved a lot more than simply converting a RAW to JPG.

I've used Photomatix on scores of shots that I simply couldn't have had acceptable results using Photoshop alone.

Of course, there is the possibility that you a just a much better man that I am when it comes to post-processing -- in which case I salute you and encourage you to do what works best for you.

As for me, Photomatix Pro has been indispensable. To each his own.
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Old Feb 13, 2010, 10:02 PM   #14
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Chato, you said you processed the picture in your "normal" way, leaving out one step. Either the original was a shot that didn't need HDR in the first place or your "normal" processing before Photoshop and/or HDR involved a lot more than simply converting a RAW to JPG.

I've used Photomatix on scores of shots that I simply couldn't have had acceptable results using Photoshop alone.

Of course, there is the possibility that you a just a much better man that I am when it comes to post-processing -- in which case I salute you and encourage you to do what works best for you.

As for me, Photomatix Pro has been indispensable. To each his own.
Walter, if you go back to my first post, I posted eight images. These include an image with the "final" normal processing step.

That image does NOT have the dynamic range of the Photomatrix version (although tje colors are more accurate).

Finally, I took the same three images that I used for Photomatrix, (a two stop difference) and using the Photoshop Layers option combined them to create a version (which in my opinion) is Better than the Photomatrix version.

Since I am not an expert with Photomatrix (although I spent quite a while to achieve the best results I can with that program) I posted a link to the original RAW version so that others could give it a shot.

(BTW: After completing these shots, I ran them all through Noise Ninja, using identical settings, before posting)

In my opinion, the PS, three layer version, is superior to the Photomatrix version - In other words, I can create superior HDR images simply using the processing tools that Photoshop provides. The qualification to this statement is that it ONLY holds true for RAW single shot images.

To use Photoshop for three seperate exposures, while it can be done, would involve to much work to be practicle on a regular basis (i.e. ghosting and alignement problems)

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Old Feb 13, 2010, 10:02 PM   #15
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well, you are really not showing HDR here if you are using 1 original image. no matter how you feed the machine, you are really creating a pseudo-hdr. even if you then created a resultant 3 exposure group to feed the photomatix program, the dynamic range is still limited by the dynamic range of the sensor.

what you are really doing here in essence is comparing your own photoshop skill in increasing global contrast, local contrast and saturation. to the tone-mapping algorythms and subsequent variations based on slider position in photomatix.

so with a pseudo-hdr basically what you are seeing is not a hdr, but the illusion of 1 through tone-mapping. tone-mapping, while i don't understand it completely, it goes something like this (someone correct me if i am wrong). it attempts to trick the human eye by greatly enhancing local contrast, so it will tend to lighten the areas around dark pixels and vice versa, tricking the eye into thinking the dark objects are darker than they are, etc. this local contrast boost gives the image the illusion of greater detail, because of the sensitivity of the eye to this contrast. there is some other stuff, but thats the important part.

if you make a natural looking pseudo-hdr, then your local contrast would not be over the top, your saturation wouldn't be that high. so it really stands to reason that you could mimic this to some degree on your own in photoshop.

true-hdr photos take several images from several different exposures to extend the true dynamic range of the photograph beyond what could be accomplished with 1 single exposure. and then simply tone-maps this.

however, if you take several different images at different exposures and combine them via layers, with enough tinkering, you could easily increase the subsequent dynamic range as well, and produce something pleasing. something landscapers have been doing for years and years. then you can tweak your saturation and contrast with good photoshop skills to replicate something similar to what you would get with HDR, or natural HDR anyways.

its a little more difficult to replicate the high intensity HDR photos that some love, and some hate.

because unsharp mask operates on a similar philosophy of increasing local contrast. you could possibly mimic some of the halo mapping by using an unsharp mask layer with a small amount but a huge radius, this will give you tons of local contrast and something that has been used in black and white photography at least for a while.

in the end, photomatix is not really doing anything magical, but it simplifying a ton of steps that would require alot of photoshop knowledge and time. (but then again, maybe it does something magic that is beyond my knowledge of the software)
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Old Feb 13, 2010, 10:11 PM   #16
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well, you are really not showing HDR here if you are using 1 original image. no matter how you feed the machine, you are really creating a pseudo-hdr. even if you then created a resultant 3 exposure group to feed the photomatix program, the dynamic range is still limited by the dynamic range of the sensor.
You may or may not be correct. Keep in mind that a RAW file actually does allow a two stop alteration in the digitial negative (both up and down, equalling four stops). The term "pseudo HDR" does not truly describe using a RAW file. It would be more accurate to describe a JPEG, but this is NOT a JPEG, it's a digital negative.

Glancing at this forum, you can see many examples of HDR done on a single RAW file.

To be completely honest here, I suspect you CAN get more out of true three shot exposures - But I strongly doubt if the improvement would be qualitative. Meaning that you might very well tweak a little bit more, but not to the point where it would make the observer notice the difference without pixel peeping.

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Old Feb 13, 2010, 10:22 PM   #17
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You may or may not be correct. Keep in mind that a RAW file actually does allow a two stop alteration in the digitial negative (both up and down, equalling four stops). The term "pseudo HDR" does not truly describe using a RAW file. It would be more accurate to describe a JPEG, but this is NOT a JPEG, it's a digital negative.
maybe the term psuedo-hdr does pertain only to jpeg, however i still see any kind of hdr that doesnt come from true multiple exposures as in some degree faking it.

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Glancing at this forum, you can see many examples of HDR done on a single RAW file.
that is true, and i have used it myself. i just think its a different animal than an hdr from separate exposures.

Quote:
To be completely honest here, I suspect you CAN get more out of true three shot exposures - But I strongly doubt if the improvement would be qualitative. Meaning that you might very well tweak a little bit more, but not to the point where it would make the observer notice the difference without pixel peeping.
i think you are right for some scenes it would be very difficult to tell the difference. however, there are other scenes with great contrast, i.e. some sunrise/sunset etc that simply could not be replicated with 1 image. you could easily take a 5 shot bracket from -4 to +4 and really increase your DR.

anyways, its an interesting discussion whatever the true answer may be. and there is no reason not to use whichever is suitable for the scene.
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Old Feb 13, 2010, 10:37 PM   #18
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i think you are right for some scenes it would be very difficult to tell the difference. however, there are other scenes with great contrast, i.e. some sunrise/sunset etc that simply could not be replicated with 1 image. you could easily take a 5 shot bracket from -4 to +4 and really increase your DR.

anyways, its an interesting discussion whatever the true answer may be. and there is no reason not to use whichever is suitable for the scene.
Without getting into a dispute about those HDR shots in which the scene is presented as sureal, and limiting this to to images which display the dynamic range that the eye see's, I believe that the normal tools of Photoshop can in fact display that dynamic range.

(Let me pause and state, that using Photoshop filters I can create images as garish and sureal as anyone would desire )

Saying all of the above, some images are better suited to HDR than others. And once again, to be honest, my final version of the image (without using three layers) would be good enough for me to present. (Not that this image is anything to write home about)

Unfortuately I don't archive RAW files, so I simply used the most appropriate shot that I took this morning.

Even so, even so, I honestly believe that I have made my point. I did my absolute best to make this a fair test, even avoiding the tweaking of my three layer shot, which I could have done to drive in the point! For example, as I stated before, there is actually more detail in the shadows of my three layer version than the Photomatrix version.

When I get a chance to head to the beach, or when another opportunity presents itself, I'll post another bunch of examples.

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Old Feb 14, 2010, 1:18 AM   #19
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your never going to create a true hdr image from one file even by stepping the values if it was that easy even the pros would do it there is a major differnce between a true hdr image and a psuedo ..... im not saying dont use photoshop as im always willing to learn new things but the likes of photomatix makes things a lot more easier .... but many will use photoshop after they have created there hdr to create / tweak there final image ,,, how long would it take you in photoshop to create something like this http://www.facebook.com/album.php?ai...id=44511593477 the reason i post this link is because it is another example of hdr and those results are what i aim for one day

i also downloaded your image but it is unworkable for some reason ?
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Old Feb 14, 2010, 2:24 AM   #20
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Having played with the maths behind this in some detail for a couple of weeks, I think it depends on what you are trying to achieve, the scene you are trying to achieve it on and those both then dictate what source files you therefore need.

Essentially for any program, the maths takes a histogram for an 'area' of the original scene and equalizes it to give a full range. That's it - nothing cleverer than that.

The hard part is defining an 'area' for comparison. My interpretation of Photomatix results is that it's using something relatively simple such as a circular area which should be fast but gives halos which sometimes need to be corrected. I guess using layers in Photoshop involves some *potentially* complex masking to use different parts of each image. My program is creating those masks with some sophisticated fuzzy edge analysis but that makes it slow.

Anyway, different situations:

1/ In a scene where each element of the scene contains a range of tones from black to white then there is very little to do and a single JPEG can be good enough (for screen display anyway). You won't see much difference except some local sharpening. The dynamic range of the image can't be more than the dynamic range of the scene and some scenes just aren't dynamic in that way.

2/ In a scene where each element doesn't contain a full range of tones (so some parts are under exposed and some over exposed) but nothing is actually clipped then even with a jpeg you can equalise this pretty well but a RAW will obviously contain more levels so should give better, smoother results. This is pseudo-HDR.

3/ In a scene where some elements are so dark that they are clipped to black or blown to white by the range of a single sensor then you can only extend this range with multiple exposures. This gives some amazing looking results but can look surreal as Chatto says if you extend the range beyond what the eye would have naturally resolved. It's giving you a 'super-vision' version of the scene. This is true-HDR.

Just my interpretation. I think the mistake a lot of software is making is that it's trying to simulate what the eye does and forgetting the other half of the story which is what the brain does.
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