Cloud problems in a true HDRI image?

Canon EF 28-135mm f/3.5-5.6 IS USM

02/13/2007 12:14:23 PM · #1

This is an attempt at true HDRI processing using Photomatix and 3 exposures. The 3 exposures were taken in a total of 12 seconds. One problem is I see duplication in the clouds. I know they were moving, but apparently they were hauling pretty good.

Thoughts on the processing as a whole and on what to do with the clouds in specific?

TCGuru

Canon EOS-40D

02/13/2007 12:16:41 PM · #2

In HDRI processing, can you mask out anything?? For instance, one layer of the clouds??

I don't know, it is just a thought...

Elvis_L

Canon EOS-5D Mark II

Canon EF 17-40mm f/4.0L USM

02/13/2007 12:18:33 PM · #3

you can open jsut one file in photomatix (the proper one) and it will hdr the one raw(assuming you are using raw) then if you like the clouds you can overlay them and mask off the rest of the image you already have

Canon RF 24-70mm f/2.8 L IS

02/13/2007 12:19:16 PM · #4

Does anybody know what the "ghosting" option is? Is that supposed to handle stuff like this?

kirbic

Canon EOS R5

02/13/2007 12:21:05 PM · #5

Originally posted by DrAchoo:

Does anybody know what the "ghosting" option is? Is that supposed to handle stuff like this?

It's supposed to, but I haven't had the opportunity to try it. I guess you have one!

02/13/2007 12:32:20 PM · #6

Originally posted by kirbic:

Originally posted by DrAchoo:
Does anybody know what the "ghosting" option is? Is that supposed to handle stuff like this?

It's supposed to, but I haven't had the opportunity to try it. I guess you have one!

You know, I think I did try it, but there are a few different options and I didn't really know what I was doing. Apparently it didn't make a big difference.

Nikon AF-S NIKKOR 24-70mm f/2.8G ED

02/13/2007 12:34:31 PM · #7

OK, another question while I'm on it. When using Photomatix, how can I adjust WB on the RAW images that are going to be used for the final image?

kenskid

Nikon D700

02/13/2007 12:36:12 PM · #8

I have not come across the "ghosting option" in my copy of Photomatix...the only thing close would be the "attempt to align the raw files" before converting.

Originally posted by DrAchoo:

Does anybody know what the "ghosting" option is? Is that supposed to handle stuff like this?

Greetmir

Nikon D60

Sigma 18-200mm f/3.5-6.3 DC OS for Nikon

02/13/2007 12:45:07 PM · #9

If you find an answer, please post it here. I have been experimenting with HDR and I find that clouds are a BEACH!

P.S. Gorgeous foreground in this example shot btw!

Message edited by author 2007-02-13 12:47:12.

Leica 35mm f/1.4 Summilux M Aspherical MF - Black

02/13/2007 12:46:21 PM · #10

When you select Generate HDRI and select multiple files, a new window opens. One of the boxes is:

Attempt to remove ghosts:
Detect ghosted areas automatically (normal or zealous)
Let me define ghosted images myself

However, the second option is browned out and I can't figure out how to activate it.

scarbrd

Leica M10

02/13/2007 12:47:49 PM · #11

Originally posted by DrAchoo:

OK, another question while I'm on it. When using Photomatix, how can I adjust WB on the RAW images that are going to be used for the final image?

I don't see a white balance control either. I usually take what Photomatic gives then bring into PS for the color adjustments.

I'd like to hear if anyone else has been able to adjust the color temp (white balance) too.

kenskid

Nikon D700

Nikon AF-S NIKKOR 24-70mm f/2.8G ED

02/13/2007 12:49:29 PM · #12

My god...I have never seen these options !?!?!?

Originally posted by DrAchoo:

Greetmir

Nikon D60

Sigma 18-200mm f/3.5-6.3 DC OS for Nikon

02/13/2007 12:52:44 PM · #13

BTW Doc ... I LOVE your Blue Eyes...Green Nose. It is one of the most gorgeous child portraits that I have ever seen in my life, IMO.

02/13/2007 12:58:37 PM · #14

Originally posted by Greetmir:

BTW Doc ... I LOVE your Blue Eyes...Green Nose. It is one of the most gorgeous child portraits that I have ever seen in my life, IMO.

Thanks Greetmir. One of my favs naturally since it's my daughter.

I'm working through another processing job and I think the zealous makes a difference. I also found on that same window is an option to input a custom WB temp. I still wish I could get the "manually define ghosting" option to work.

Artifacts

Canon EOS-5D Mark II

02/13/2007 01:04:45 PM · #15

Interesting problem. Movement between shots is always a problem with mult-imaged compositions.

I'd guess that 'ghosting' has to do with correcting camera movement and therefore looks at the whole image to look for and correrct for it. Seems doubtful it would be smart enough to figure out only clouds are moving and correct for that. That would be a sophisticated algorythm.

Probably the only way to get rid of the duplication is to copy the same sky into all three images prior to HDR.

Message edited by author 2007-02-13 13:04:59.

Gordon

RIM BlackBerry Curve

Canon EF 85mm f/1.8 USM

02/13/2007 01:18:26 PM · #16

This comes back to something I mentioned yesterday, about perhaps attempting a multi-step HDR processing and masking regions out. The trick would be working out what value is considered 'neutral' for HDR processing - i.e., that would have no effect when combined with another image.

Either you could copy parts across images prior to HDR processing, or find that neutral value (though I don't think it exists, unless photomatix has or introduces alpha channel support - which would be very cool)

Either that, or do your HDR processing in multiple steps and mix the results together with layers in photoshop.

Like most things, the automated approaches only take you so far.

Gordon

RIM BlackBerry Curve

Canon EF 85mm f/1.8 USM

02/13/2007 01:20:13 PM · #17

Originally posted by stdavidson:

I'd guess that 'ghosting' has to do with correcting camera movement and therefore looks at the whole image to look for and correrct for it. Seems doubtful it would be smart enough to figure out only clouds are moving and correct for that. That would be a sophisticated algorithm.

I doubt the current HDR tools do anything like that, though the sort of algorithm you describe is pretty much a solved problem for video encoding, so could equally well be applied to HDR alignment.

02/13/2007 01:21:49 PM · #18

Originally posted by kenskid:

My god...I have never seen these options !?!?!?

Originally posted by DrAchoo:
When you select Generate HDRI and select multiple files, a new window opens. One of the boxes is:

Attempt to remove ghosts:
Detect ghosted areas automatically (normal or zealous)
Let me define ghosted images myself

However, the second option is browned out and I can't figure out how to activate it.

The options are on the latest version of Photomatix Pro (2.4 Beta 3 is what I run). If you own the program, you can upgrade for free.

R.

02/13/2007 01:23:24 PM · #19

Ya, I agree Gordon. I'm starting to be glad I only paid $30 for Photomatix because, while it's great for 640 pixel shots, it is quite limited for anything that is going to be sold as a print.

I think, in general, I can do a much better job manually with converting RAW shots myself and then masking in or out the sections I want more detail in.

I'm still working on the shot, but have already pasted in a section on the brightest clouds which really had problems in the photomatix version.

02/13/2007 01:30:02 PM · #20

Originally posted by DrAchoo:

I currently solve that problem by doing HDRI on such scenes by effecting multiple processing of the same RAW exposure into 16-bit TIFF, and then merging those. I have tried the "ghosting" option and it does not work for me on clouds. It DOES work fairly well on things like ghosting foreground twigs and leaves. My "Winter Sunset" Image shows evidence of ghosting in the clouds, actually, but it is acceptable, not exaggerated. That was from 4 RAW exposures converted to TIFF and merged.

As far as your question about processing RAW images before doing HDRI merges with them, I do that all the time: I process the RAW to 16-bit TIFF and generate my HDR merge from the TIFFS. If you use Photomatix to generate HDRI "directly", Photomatix is (as far as I can tell) decoding the RAW to TIFF anyway, so I just do it myself. This gives me the most control. Contrast adjustments to the RAW images can have a significant effect on the final HDRI rendering.

R.

Olympus 40-150mm f/2.8 PRO M.Zuiko

02/13/2007 01:35:13 PM · #21

Originally posted by DrAchoo:

That's not my experience. "Winter Sunset" took second place in a juried show as a 16x20 image, and the print has been sold for $350, framed and matted.

But one thing I do a lot of is merge the HDRI image with the original, "best for light areas" image. I overlay the original on the HDRI image and set the layer to "lighten" mode. This cleans up a lot of murkiness in the bright areas, making them crisper and sharper. To a certain extent this solution helps solve cloud ghosting as well. But its main virtue is that a tone map that works best for the darker areas will often show a grungy, pale gray buildup in flatter, bright areas, and the "lighten" overlay cleans that up very well.

R.

Brad

Olympus OM-D E-M1

02/13/2007 01:59:59 PM · #22

Originally posted by Bear_Music:

The options are on the latest version of Photomatix Pro (2.4 Beta 3 is what I run). If you own the program, you can upgrade for free.

Have you seen any difference using the setting "Attempt to reverse-engineer tone curve applied" ?
I'm not sure if the earlier version had the Undo last setting & Redo the last setting buttons in the lower left. The symbols were hieroglyphics until changing a setting. Guess that's what Beta means....

02/13/2007 02:49:02 PM · #23

Originally posted by Brad:

Originally posted by Bear_Music:
The options are on the latest version of Photomatix Pro (2.4 Beta 3 is what I run). If you own the program, you can upgrade for free.

Have you seen any difference using the setting "Attempt to reverse-engineer tone curve applied" ?
I'm not sure if the earlier version had the Undo last setting & Redo the last setting buttons in the lower left. The symbols were hieroglyphics until changing a setting. Guess that's what Beta means....

NO, I haven't tried it. I am refusing to explore new options until I have nailed the ones I am already familiar with LOL. Too much input is bad for my brain. On the plus side, my HDRI/tone mapped images are getting more subtle, for the most part :-)

R.

Melethia

Canon EOS-80D