HDR (high dynamic range)

[boBQuincy]

While we are discussing this, digital obviously does not have the range of some films, especially B&W, *but* digital does have the capability to merge different exposures to surpass the range of any film.

A fine example of this being put to very good use is at:

http://www.sjphoto.com/parks_project_photos.html

HDR may be the next big step, where any subject can be properly exposed from full black to glarnig white, and still capture all the values in between.

 

[Lachesis00]

I look forward to seeing conversation on this. I am seeing HDR more and more on other photography boards....

 

[gruZ]

Most people reading this thread may have read this one, but a lot of the discussion there had to do with HDR.

 

[tinksdad]

HDR is VERY intersting to me. I've been dabbling with the process, with mixed results. I've got to remember to bracket the shots to get the best results.

Fun stuff though!

 

[Anewman]

HDR is VERY intersting to me. I've been dabbling with the process, with mixed results. I've got to remember to bracket the shots to get the best results.

Fun stuff though!

In theory, you may not be required to bracket.
If one shoots raw you can convert with different exposure compensation settings to give you a bracketing effect.

 

[boBQuincy]

In theory, you may not be required to bracket.
If one shoots raw you can convert with different exposure compensation settings to give you a bracketing effect.

That is one way, it doesn't really give more dynamic range but utilizes all the range the sensor can deliver, where jpg often tosses many of the values away.

I found the Nikon D2x allows more than three exposures for bracketing, maybe others will follow.

 

[bostran1]

I've been having a heck of a time creating an HDR from single RAW files so I thought I would post and hopefully get some feedback.

I have tried this with several RAW files from different lighting conditions (day and night) and the whole range of ISOs (100-1600) and I cannot figure out how to get a useable HDR from a single RAW file.

Anyway, I have been using photoshop CS3 to convert my RAW files to jpegs. I have used 3 exposures (-2, 0, 2). I have even used the Cannon converter that came with my XT. But, when I put the converted jpegs from the RAW file into Photomatix and merge to HDR and go through every setting of hte tone mapping I always end up with an HDR full of noise. And I'm talking some serious noise, like nothing I've seen on a normal picture taken at a high ISO in the darkest of dark conditions. The RAW file itself is pretty much free of noise so I cannot figure out what is going on.

Any suggestions would be appreciated. Here is a sample. Sorry its so large but if you look at my girlfriend's skin, especially the legs, you can clearly see the noise (usually the black shorts have looked horrendously noisey), this is actually one of the better ones I ended up with. Maybe I'm just not getting something about RAW conversion?

 

[Furgus]

Ben,
I just tried it too from a single file in the newest version of PhotoMatrix. I got a lot of noise in the very dark areas of the photo. I had no noise when I merged three different images. It is strange.
Take a look at this, and it might help, course it might not.

Stuck In Customs

 

[tinksdad]

I've been just using the RAW files right into Photomatix. Seems to work fine.

I think the conversion from RAW into JPG creates the problem. Try using just the RAW files right out of the camera.

 

[bostran1]

Furgus, thanks for the link. I'm trying the batch processing now. EDIT: even doing the batch processing of the single RAW file creates all sorts of noise in the dark areas. I never have this problem when working with 3 differntly exposed non-RAW images.

Kevin, when you have made HDRs out of a single RAW file are you using the batch processing? Maybe I'm just trying to create the wrong way?

 

[Furgus]

I used RAW for the three files I did (All 2 stops apart) and for the one file I used. The one image came out very noisy, and the three did not. I wonder if it was so noisy because it was so underexposed? I know if I soot in ISO 200 and I have some very bad black clipping, if I lighten up that are it is very noisy. Cold just be what is going on here regardless of file type, but I agree, do all of your HDR creation in RAW.

Good Luck.

 

[Groucho]

I haven't done it a lot of times, but when I have, I've created a bunch of JPGs at different exposure levels - more than three. I'm not sure if the extra exposures helped, but maybe? Dumping them into Photomatrix did produce a decent result. It's probably better to have too many than not enough. Here's one that turned out well, IMHO: (one of my nieces)

The original had a very underexposed face - note that the sun is behind her, a big no-no for proper exposure.

Of course, Lightroom's control over fill light, blacks, recovery, etc, help reduce the need for single-image HDR, but I think this one was either beyond what it could do, or more likely, what I could do with it!

Supposedly someone found a way to do a single-image HDR with Photoshop CS3's HDR functionality, but I don't remember the details.

 

[tinksdad]

Kevin, when you have made HDRs out of a single RAW file are you using the batch processing? Maybe I'm just trying to create the wrong way?

Using Photomatrix, I don't see a way to HDR a single file (program needs at least two files). I open the file in the file command, and then apply Tone Mapping. That gets it close to the same look as a HDR, but with just a single file. I don't like the cartoonish results that some folks reproduce and prefer them to be more realistic, just higher range. So I play with the output controls until I like the look and then save it.

Here's a couple of examples from single RAW files. This top one is the a JPG conversion with a little levels tweak.

This one I used Tone Mapping with Photomatics Pro. Extacts some of the extreme range out of the shadows and tones down the highlights a bit.

Same original RAW file, taken with a 12-24mm lens, tripod

 

[Groucho]

For single files in Photomatrix, go to Automatic, then Single File Conversion. No claims that it'll work, but for me, most HDRs seem to be a lot of black magic and shaking a chicken bone at the monitor.

 

[Furgus]

For single files in Photomatrix, go to Automatic, then Single File Conversion. No claims that it'll work, but for me, most HDRs seem to be a lot of black magic and shaking a chicken bone at the monitor.

I have done single RAW file HDR's using Photomatix. You have to change the number of photos to all, and place the RAW file you want in a folder where there are no other images. Usually I copy the RAW to my desktop and put the output folder to my HDR folder on my external HD. Little bit of a pain, but it works for me. Also use the Batch Process. I found this in a forum somewhere.

 

[Furgus]

Sorry, double post, but while I am here....this is a single file HDR conversion.

 

[bostran1]

Well I'm an idiot. I did what Kevin said above and just opened the RAW file in Photomatix. It opened it and turned into a "pseudo-HDR" file. But I still end up with the noise in the dark areas. I'll keep experimenting but thank you for the help so far.

 

[tinksdad]

Sorry, double post, but while I am here....this is a single file HDR conversion.

Cool shot!! Love the line in the boardwalk that leads the eye, nice job!

 

[tinksdad]

Well I'm an idiot. I did what Kevin said above and just opened the RAW file in Photomatix. It opened it and turned into a "pseudo-HDR" file. But I still end up with the noise in the dark areas. I'll keep experimenting but thank you for the help so far.

Some noise might be unavoidable due to the process and exposure of that portion of the shot. Have you tried Neat Image?

 

[ukcatfan]

Supposedly someone found a way to do a single-image HDR with Photoshop CS3's HDR functionality, but I don't remember the details.

Not speaking from personal experience, but I have read that all you need to do is strip the EXIF and then PS will prompt you to input the differences in exposure manually. There are free programs that will strip the EXIF data, but I believe that they typically run in batch mode, so be sure to have the files isolated to a separate folder to be safe.

Also, while it would be slower, can the HDR programs handle TIFF? That might keep the noise down.

Kevin