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View Full Version : Did I achieve HDR?



scupking
01-26-2009, 08:14 PM
Before
http://i35.photobucket.com/albums/d154/scupking/HDR%20test/Picture002.jpg
After
http://i35.photobucket.com/albums/d154/scupking/HDR%20test/Picture002HDR.jpg

Before
http://i35.photobucket.com/albums/d154/scupking/HDR%20test/Picture007.jpg
After
http://i35.photobucket.com/albums/d154/scupking/HDR%20test/Picture007HDR.jpg

Before
http://i35.photobucket.com/albums/d154/scupking/HDR%20test/Picture027.jpg
After
http://i35.photobucket.com/albums/d154/scupking/HDR%20test/Picture027HDR.jpg

Before
http://i35.photobucket.com/albums/d154/scupking/HDR%20test/Picture042.jpg
After
http://i35.photobucket.com/albums/d154/scupking/HDR%20test/Picture042HDR.jpg

Before
http://i35.photobucket.com/albums/d154/scupking/HDR%20test/Picture145.jpg
After
http://i35.photobucket.com/albums/d154/scupking/HDR%20test/Picture145HDR.jpg

D Thompson
01-26-2009, 08:34 PM
looks more like Lucis to me.

TheObiJuan
01-26-2009, 10:57 PM
I don't see any evidence of increasing dynamic range, instead I see what Dennis sees: Lucis.

Prospero
01-27-2009, 01:57 AM
This is indeed not HDR. Blown highlights in the before pictures are still there in the after pictures. There is no extension of the dynamic range at all. You can only do HDR if you take multiple shots or, arguably, if you create multiple exposures from a RAW file (though this is often not needed as shadow recovery tools in RAW editors can do a job just as good).

What you did instead is tonemap the images. Tonemapping is a part of the HDR process, but can be done on images that are not HDR. In this part you make sure that the dyanamic range you captured in the different shots can be displayed on a print or on a standard screen with decent contrast throughout the picture.
To do this, the program you use changes the contrast locally. If this is not done right, you see halos and strange effects as in your pictures. Some people like this effect, though.

Here's an example of HDR. None of the shots I took covers the full dynamic range, but when merged together, the whole picture is exposed properly.

44037

44038

Turn
01-27-2009, 03:41 AM
they're not really HDR's..

try making it a bit more...natural and Prospero has the right idea

kgosden
01-27-2009, 06:41 AM
I would say that on the first two the use of HDR techniques is a total waste. Those two images seem to have a dynamic range well within the capability of your camera's sensor. The remaining images seem to have largely lost a little highlight detail. Even there the lost highlights are largely on reflected chrome and probably should lack detail. The final photo of the woods could probably gain some detail from increased dynamic range, but I do not feel it will gain any aesthetic value.

John_Reed
01-27-2009, 06:46 AM
I took your "cars in a line" photo and just tweaked shadows and highlights in my iPhoto program:

http://john-reed.smugmug.com/photos/462798228_GYZ9K-O.jpg

Compare to your "before" image:

http://i35.photobucket.com/albums/d154/scupking/HDR%20test/Picture027.jpg

And your "after" image:

http://i35.photobucket.com/albums/d154/scupking/HDR%20test/Picture027HDR.jpg

You can see that both of us left behind some artifacts of the tweaking. Look at the halos around the car shadows in the two derivative images; none in the original. What I didn't like about your version was the muddiness and indistinct details of the background foliage. I think with a true HDR you'd have done much better than this, as one of the other posters already demonstrated.

My own experience with HDR says that a) You'd better be shooting from a tripod; and b) If there are leaves in the scene and the wind is blowing, (or anything moving, for that matter) your result may never look right?

cdifoto
01-27-2009, 07:22 AM
HDR = High Dynamic Range. That's all. Some people tonemap their images into a cartoony mess (which is what you did), but that's not HDR in and of itself.
http://www.dcresource.com/forums/data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABwAAAAOCAYAAAA 8E3wEAAAABmJLR0QA/wD/AP+gvaeTAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH1Q UUDyoqJjAqRwAAAN1JREFUOMu1lMkVwyAMBYe0JGpCNUFNVk3k 4AUwxPGS+ILxkzX8jyTH/Sfu9nrmJ3cXlnMASyWRPwd2d5XlHCBZn1BthcbRAdxTZQDI8k3 mQzg11rhF+QZ9jdNOcQib6GFQYJYgCFucSRf6GsLU6wEY5yubT FqF2yq1vRwr3INXdQUWG+je1pELX4ED1wDyRAR0WfuAA9gloIT yvsFMIMgYInYRqF6rO9Sqz9qkO5ilyo0o3YBwJ+6vrdQonxWUQ llhXeHcb/wabMPkP2n81ocAIoLZrMqn/4y2RwP8DcQ+d6rT9ATiAAAAAElFTkSuQmCC



This is an HDR:

http://i14.photobucket.com/albums/a304/cdifoto/HDR.jpg

Prospero
01-27-2009, 07:26 AM
My own experience with HDR says that a) You'd better be shooting from a tripod; and b) If there are leaves in the scene and the wind is blowing, (or anything moving, for that matter) your result may never look right?

Although HDR can be done handheld, a tripod does indeed help a lot. Especially when there is a lot of detail in the foreground you need a tripod, because otherwise it becomes almost impossible to allign the images, even with panorama software.

When making HDRs of scenes with movement, it often helps to use less source images. If only one of the your shots has the leaves exposed properly, only that shot will be used for that part of the picture.
Sometimes, it is best to use only two exposures. I often use only the two dark exposures and create the brightest by boosting the raw file one or two stops. This has several advantages. First of all, the shots are easier to allign, and secondly you will have no problem with the leaves because the two brightest shots are identical and of the darkest shot only the sky is used. Finally, when shooting in the evening, you avoid using exposures longer than a second, which reduces motion blur occurring in your shot. The downside is that the result will be slightly more noisy.

John_Reed
01-27-2009, 04:18 PM
cdiphoto: Nice HDR example. Was that light streak (representing a car, I guess?) present in ALL the frames?

cdifoto
01-27-2009, 07:47 PM
Yes it was. I cheated in this example though...I used the same RAW image but exported it as different exposures.

John_Reed
01-27-2009, 11:22 PM
Aha! Interesting thought, seems like HDR is a substitute for the range already available in RAW. So why did you need HDR with your RAW image?

scupking
01-28-2009, 08:19 PM
Lots of interesting stuff. I'm going to try it out this weekend when I have time and I will post up my results. Also I have adobe Elements 6 and I know it doesn't do HDR. Is Dynamic Photo HDR good software for HDR?

cdifoto
01-28-2009, 08:36 PM
Aha! Interesting thought, seems like HDR is a substitute for the range already available in RAW. So why did you need HDR with your RAW image?
HDR in the non-cartoony overprocessed form is combining exposures to produce an image that exceeds the dynamic range of the camera's sensor (or film).

RAW had enough latitude in this particular image to capture the data, but it did not have enough latitude to show the detail, thus the HDR. I probably could have simply boosted the shadows using curves, but hey sometimes I like to fiddle. :D