HDR's noisy as hell !!!!

[Karlo]

Ever since i got my 50D my HRD's seem to be noisy as hell, in fact i always get so frustrated that i do not even continue to tonemap them or anything i just quit. :mad::confused::(

Seen some photo ops where HDR would came in handy but ignored them knowing what i was getting as an output... So till i get the 5dmkII what software do you use and an what settings to get noise free HDR's . Just to point out i know how to make hrd's i did successfully with my old xti's images .

Thanks !

[pixelbasher]

Don't know if this helps any, but whilst my feeble attempts with my 50D may not come out how I like them, I have no problem with noise in them in the correctly exposed parts of the final hdr

See here http://photography-on-the.net/forum/showthread.php?t=675270

this is my best so far.

[Karlo]

Nah, your picture is great. I have noise that you get to se on the h2 setting of ISO when shooting and i know i always keep ISO at 100-200 when shooting for raw. What version of photomatix is it ?

[Pyromaniac]

Karlo, it would help if you post an example of what you are talking about. Maybe the setting for each shot used in the HDR as well.

[TheReal7]

samples with EXIT data would help.

Are you talking multiple RAW files or faux HDR from a single RAW? If it's the latter I'd say you are processing and underexposed image or scene you are shooting requires more then one exposure.

We need more info though to really help you out.

[Karlo]

Well, I never did faux HDR's i usually do 3 exposures sometimes 5 * i did till i got the 50D :( now i don't do any. I will post tomorrow when i get some decent light outside .

[Lazuka]

What ISO are you shooting at?

[_GUI_]

Many people complain about noisy HDR's, but they fail to know what's the origin of noise. The origin of noise is _not_ ISO (or at least ISO is not the most important cause of noise), it's _not_ the HDR tone mapping tools (they simply work with the stuff you provide them), it's _not_ the particular camera model (some cameras are noisier than others of course, but again this is not the main factor).

The origin of noise is _exposure_, so if your HDR's images are noisy, it was YOUR FAULT. You simply didn't expose enough.

The degree of noise in a particular zone of an image, or we'd better say the signal to noise ratio in that area, depends mainly on the degree of exposure achieved in the RAW file, i.e. how far from saturation was your data.

If you are doing several shots to make an HDR composite, the HDR program will usually take the most exposed or the correctly exposed RAW file as the source for each area of the image. So if some part of your image displays a lot of noise (i.e. a low signal to noise ratio) is because in none of your shots you achieved a good enough exposure in that area.
That is why the optimum way to shot HDR is not do a central exposure according to the camera light mettering, and then go to -2 and +2, or go to -4, -2 and +2, +4. The optimum way to do it is to do one exposure to the right (the max exposure with unclipped highlights), and from that reference start to overexpose +2, +4, +6,...

I will just give you an example: this scene was shot 3 times being the least exposed shot the one on the left, which keeps the highilights I wanted to keep (the lamp basically) unclipped. And from that I did +2 and +4 overexposure (the image on the right is the blending map, indicating the source image from were information was taken in the set of 3 shots):

http://img25.imageshack.us/img25/5345/fus.jpg

After optimally blending and tone mapping with 2 curves, a noiseless image is obtained because all areas of the scene were properly exposed in at least one of the shots:

http://www.guillermoluijk.com/tutorial/hdr/resultado9.jpg

So to avoide noise: expose as much as you can the least exposed shot in your set of images, and from it start to overexpose until the darkest region of the scene gets a good exposure in at least one of the RAW files (or source images).

BR