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iNfEk
29th of August 2008 (Fri), 14:37
I maybe missing something here but in some of my HDR images where the subject is white (i.e. a car or building that's predominantly white or clouds in the sky looking like storm clouds) the end results in a grey cast rather than the subject being white. Are there particular settings that I should be looking at to keep the whites white? I've done some post processing with layers after the fact to make my whites white and not grey but I figured there has to be an easier way or a direct way in Photomatix.

please share your secrets if there are any.

Sorry if this has been brought up before but I've searched and couldn't find what I wanted.

Here's an example of an earlier attempt (I still think it's good but need improvement):

http://farm4.static.flickr.com/3156/2762404466_fae8a76246_o.jpg

here's an update to that image I just did

http://farm4.static.flickr.com/3103/2809392254_75fdbca2a2_o.jpg

Thanks,

Jon

lefturn99
29th of August 2008 (Fri), 15:27
I don't have the program handy, but keep the strength slider to the right and only use the last two radio buttons. 'Try the white point. Course, that wipes out the "painterly" look. Otherwise, Photoshop.

Swift1
30th of August 2008 (Sat), 16:31
Are you saying that your car is supposed to be white, and not gray?

I would open the HDR photo in Photoshop, and a photo of your car where it is white (in the same position as the HDR photo) and then apply a layer mask.

iNfEk
30th of August 2008 (Sat), 16:34
It was just an example but yes the car should be white not grey looking.

I've been doing that most of the time (not in this example) but figured there had to be an easier way... I guess nothing comes easy :doh:

Thanks,

Jon

canonloader
24th of September 2008 (Wed), 10:09
What did you do in the Updated version? Noise removal? It got rid of the metal flake look for sure.

I can't help on the white point question, however, I did find out a nice bonus with PM, e-mail their support people with the problem. I got an answer to one I sent in in a couple hours, and they followed up for me very fast over several mails, and we got the problem solved. [Which was how to open 1D Classic RAW tiffs in PM at the correct size.] ;)

Seaboarder
24th of September 2008 (Wed), 10:45
I use HDR when necessary but never make any adjustments in the program.
I stick to the tone mapping defaults and then complete the job in Photoshop.
For me the results are far superior.

tmcman
25th of September 2008 (Thu), 09:34
I'd like to hear what the support people say to you.
When PM see white pixels
how does it know if they were white to begin with
or if they are blown/overexposed pixels?
How does it avoid choosing underexposed pixels to use in the tonemapped final of a white object?

Kittygraphix
25th of September 2008 (Thu), 09:41
Is the car a stark white out of camera?

kirkt
25th of September 2008 (Thu), 15:39
It appears to be your combination of contrast and smoothing. Although I don;t know what process you used to shoot your image sequence, etc., I assume you used Photomatix Detail Enhancer for tonemapping. Play with the "Light Smoothing", "Microcontrast" and "Micro- Smoothing". It looks like tonemapping is bringing out contrast in the subtle shading variations in the body of the vehicle, making the vehicle body gray. You want to smooth or decrease these areas of higher than desired local contrast. Also, try using the "Tone Compressor" tonemapping operation instead of the Detail Enhancer as well, or exposure blending. Then, in PS, you can color correct as necessary - similar to what Seaboarder is suggesting. In other words, the final image does not need to come from Photomatix, just a decent tonemapping of the HDR data. Also, simply shifting your white point in Photomatix to blow out the body to "white" is probably not what you want to do, and it already appears that you have clipped the lighting in the scene, so that will only get worse.

Kirk

artificialharmonix
26th of September 2008 (Fri), 00:57
push the highlight smoothing in photomatix a bit. it/s in the S/H tab.

iNfEk
5th of October 2008 (Sun), 16:38
Thanks for the suggestions.. been so busy haven't been on here lately.. I will play more with it.

yes I did do some noise corrections. most of my HDR images are ran through PS before I'm completely happy with them. The car is more of a brighter white and in comparison to other whites it's far brighter. PM could be seeing the white as a highlight.