Help me with HDR techniques

I'm just trying to get my toes wet with some hdr stuff. I've read a couple tutorials on the process, gave it a shot in cs4...which did not turn out well at all, but I have some questions. Rather then taking multiple shots and having to risk them being unaligned (ps tends to freeze when auto-aligning during the hdr merge), why not just take one image (in raw?) bracket the exposure a couple times, then flatten those images? Feel free to throw in any other advise, or move this if this is the wrong forum.

I´m no expert at all, but I think there is no problem at all with the bracketing technique that you mention. Actually I have thought about doing exactly that, to give HDR a try on my own with the may pics I have, which non of them were taken with bracketing within the camera.

The difference is in how the digital sensor records light.

You could certainly use your method ( which, by the way, is called 'tone-mapping', and is an important part of the HDR process) and you'll likely get an improved image. But it won't be HDR.

Digital cameras capture light and detail in a non-linear fashion. A full 50% of the images' detail is in the brightest stop of the image. 50% of what's left (or 25% of the total) is captured in the second-brightest stop. 50% of the remainder (12.5% of the total) is in the third stop, and so on.

So when you bracket an image, you're capturing that first 50% in different parts of the image, then using the 'merge to HDR' to combine them into an image that has more information, more detail, than any one of the individual images.

I hope that makes sense.

- Joe U.

A bit. I'm mainly looking for alternatives in how to do it since ps has been crash happy on me lately. It might have something to do with the raw plugin I had to install as RAW wasn't reading the nef files from my d90 like it did with my d40.

Oh, well then, why didn't you say so?:D

Look into Photomatix. You can download a trial version, but it will watermark the result. It's a standalone program, not a PS plug-in.

Here's the link: http://www.hdrsoft.com/index.html

- Joe U.

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Originally Posted by thecounsel

I'm just trying to get my toes wet with some hdr stuff. I've read a couple tutorials on the process, clip....
Rather then taking multiple shots and having to risk them being unaligned (ps tends to freeze when auto-aligning during the hdr merge),

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This is why you purchase a stable tripod and head. A good tripod will keep all the multiple exposures aligned. HDR photographs really can't be hand held, unlike panoramas.

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Originally Posted by thecounsel

why not just take one image (in raw?) bracket the exposure a couple times, then flatten those images? Feel free to throw in any other advise, or move this if this is the wrong forum.

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This is not HDR like "Medley" said, the multiple exposures get the data lost with only one exposure as raw only gives you maybe two stops of range, a true HDR gives at least 4 or more F stops of range, fully depends on the type of exposures and the number of exposures.

As others already mentioned, you really want to use multiple exposures, even when using RAW, the wider the range , the better image you will obtain

Photomatix does an splendid job.

Also you want to use a tripod to get a quality photo, otherwise even when using auto-align it may look blurry.

I do use a tripod with a D40 , so I have to be touching the camera for the different settings, my tripod is not very solid, so I still use the auto align feature

I have used a program on my laptop to control the bracketing, this avoids touching the camera at all during the process of the multiple exposures, obtaining fantastic results.

Once the image has been tone mapped save it as a Tiff, so further processing can be done with say photoshop or any other favorite program you may have.

I believe you should be able to view this thread without having to log in/have an account on the site, but this is a good tutorial for those using photomatix.

http://www.uer.ca/forum_showthread.a...threadid=70801

Well, I buckled down and got photomatix since ps wasn't cutting it. 10 images in RAW with some more playing after they were all merged

http://gallery.photographyreview.com.../backyard2.jpg

I like it. And I think you'll be pleased with Photomatix.

- Joe U.

Interesting subject. I got a doubt about all this. Is RAW a most on all this or can I shoot lets say 3 bracketed JPGE´s? I ask this because my camera (E-420) does not improve much shooting RAW..either the JPGE´s are great quality or the RAW is somehow poor. If RAW is not a most I prefer to shoot JPGE in order to save some card space.

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Originally Posted by BlueRob

Interesting subject. I got a doubt about all this. Is RAW a most on all this or can I shoot lets say 3 bracketed JPGE´s? I ask this because my camera (E-420) does not improve much shooting RAW..either the JPGE´s are great quality or the RAW is somehow poor. If RAW is not a most I prefer to shoot JPGE in order to save some card space.

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You can use jpg files, but you would have to overlap them a lot more since the RAW contains a larger exposer range (even if not visible). - TF

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Originally Posted by OldClicker

You can use jpg files, but you would have to overlap them a lot more since the RAW contains a larger exposer range (even if not visible). - TF

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Ok Thanks OC so I´ll need more JPGEs then:thumbsup:

Well, I figured I'd post a couple that I've done so far since down loading photomatix

This one was done with one jpeg bracketed after the fact. This is also about where I was hiking a couple days ago when I realized I was lost, and far off the trail. Not good in puma country.
http://gallery.photographyreview.com...um/desert2.JPG

These next two were done closer to the "right" way. Three shots in RAW, auto bracketing done by the camera. VR and three quick bursts seemed the do the trick rather well.

I shot this while waiting for some trains to come...which never did. But did 5 minutes after getting home :(
http://gallery.photographyreview.com...ssingmuted.jpg

I'm rather proud of this one, taken at the Pima County Air Museum
http://gallery.photographyreview.com...dium/plane.jpg

I attended a one day 'photo school' last weekend and part of it was a presentation by Adam Jone (Canon Explorer of Light). He emphasized for the low exposure shots, you need to get the right side of the histogram near the center. Same for the left side and the shots on the high end. - TF

You should look into the "Exposure Fusion" aspect of Photomatix. It requires you to take the images in RAW, the process them into tiff files (set all sliders at 0). Still the result is has much less noise, no halos, and avoids the 'painterly' effect common in HDR's.

The downside is that the more images you process, the more RAM you'll need.

Also, while we're on the subject, you should use Raw files for HDR work. Jpeg give you 256 possible colors, Raw gives about 4000. The difference is difficult to see with the naked eye (which con only differentiate about 250 tones), but Photomatix will have a much easier time, and create a smoother transition, using the Raw images.

- Joe U.

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Originally Posted by thecounsel

Well, I figured I'd post a couple that I've done so far since down loading photomatix

This one was done with one jpeg bracketed after the fact. This is also about where I was hiking a couple days ago when I realized I was lost, and far off the trail. Not good in puma country.
http://gallery.photographyreview.com...um/desert2.JPG

These next two were done closer to the "right" way. Three shots in RAW, auto bracketing done by the camera. VR and three quick bursts seemed the do the trick rather well.

I shot this while waiting for some trains to come...which never did. But did 5 minutes after getting home :(
http://gallery.photographyreview.com...ssingmuted.jpg

I'm rather proud of this one, taken at the Pima County Air Museum
http://gallery.photographyreview.com...dium/plane.jpg

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Hey..........think you need to pull back the strength slider in photomatix as the 1st and 3rd have huge halos around the outlines, the second does not look properly aligned either

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Originally Posted by vmlopes

Hey..........think you need to pull back the strength slider in photomatix as the 1st and 3rd have huge halos around the outlines, the second does not look properly aligned either

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I agree with you on the alignment...I mostly try my luck with doing them hand held, but I've also realized that aligning be features seems to be more effective. As far as the halo's go, I'm not necessarily trying to make each on convincing, just trying to make stuff that looks cool. I'll get to the more straight forward applications in a bit. Thanks for taking a look and sharing your thoughts though...it's good to get feedback.