Posterization - 5D III HDR

[FloridaNature]

I really love the HDR effect (natural) from the 5D3 and it is hard to get close to it using other HDR programs but a HUGE drawback is the posterization I get in the final image out of the camera when shooting sunrise or sunset shots.

I shoot RAW - Keep the three master files and the JPEG HDR image that the camera makes.

Is there ANY setting to prevent this? Color space?

Thanks,
Michael

 

[Skirball]

Color space isn't going to have an impact on posterization. Technically you're going to get it anytime you decrease the bit depth of an image. But you can minimize the visual impact of the final image.

I've never used in camera HDR for this reason, you lose control of the process. HDR & tone mapping are far too complicated of a process to leave up to the camera, IMHO. If the result really is unusable then I'd recommend giving a program like Photomatix or Enfuse another go. I'm certain that there's nothing that your camera can do that either of these programs cannot. It just takes some practice to get the results you want.

 

[Wick]

I really love the HDR effect (natural) from the 5D3 and it is hard to get close to it using other HDR programs but a HUGE drawback is the posterization I get in the final image out of the camera when shooting sunrise or sunset shots.

I shoot RAW - Keep the three master files and the JPEG HDR image that the camera makes.

Is there ANY setting to prevent this? Color space?

Thanks,
Michael

A sunrise or sunset does have an enormous range of tones, and automatic processing is going to be severely challenged to produce a good result. I forget whether in HDR mode on the Mk III you can set the number of images to take. For a shot like the one you describe, I would think that 5 or 7 images might be necessary to prevent posterization.

Another thought, if 3 shots is the only option, is to play with exposure. Perhaps overexposing slightly would produce more sensor information and reduce the abrupt tonal changes you are seeing.

 

[Skirball]

A sunrise or sunset does have an enormous range of tones, and automatic processing is going to be severely challenged to produce a good result. I forget whether in HDR mode on the Mk III you can set the number of images to take. For a shot like the one you describe, I would think that 5 or 7 images might be necessary to prevent posterization.

Why would more images help reduce posterization?

 

[Wick]

I think so. Posterization is a form of excess dynamic range. The tones don't have enough variation for smooth transitions. A 32-bit image should have little or no posterization if there are sufficient tones to choose from in the creation of it.