How to merge 2 HDR images?

I have 2 HDR images (32bit) opened in Photoshop CS2 and want to merge them to one HDR image. The internal "merge" Function of Photoshop will reduce both images to 8 bit and merge then. The "merge to HDR" function does not work with HDR images as source.

So what can I do?

Thank you,
Christian.

Christian Drewing wrote:

I have 2 HDR images (32bit) opened in Photoshop CS2 and want to merge them to one HDR image. The internal "merge" Function of Photoshop will reduce both images to 8 bit and merge then. The "merge to HDR" function does not work with HDR images as source.

So what can I do?

Thank you,
Christian.

Try http://www.astro.leszno.net/easyHDR/

"Christian Drewing" wrote in
message

I have 2 HDR images (32bit) opened in Photoshop CS2 and want to merge them to one HDR image.

Could you explain what you mean by "merge them to one HDR image"?

Do you want to blend them, combine parts of them, make a montage? That cannot be done. You need to change their mode to 16-bits/channel to do that. Or, if the HDR images were created by merging LDR images, maybe you could blend the LDR image components and then merge into an HDR image.

--
Bart

He wants to take two 32-bit HDR images and combine them in to one. Basically what he wants it to use the two HDR images in Photoshop's merge to HDR as the source files.

R

"Bart van der Wolf" wrote in message

"Christian Drewing" wrote in message

I have 2 HDR images (32bit) opened in Photoshop CS2 and want to merge them to one HDR image.

Could you explain what you mean by "merge them to one HDR image"?
Do you want to blend them, combine parts of them, make a montage? That cannot be done. You need to change their mode to 16-bits/channel to do that. Or, if the HDR images were created by merging LDR images, maybe you could blend the LDR image components and then merge into an HDR image.
--
Bart

Hebee Jeebes wrote:

He wants to take two 32-bit HDR images and combine them in to one. Basically what he wants it to use the two HDR images in Photoshop's merge to HDR as the source files.

Yep, that is clear. But what's the point? Those 2 HDR images must have come from merged originals, so why not merge those two sets of originals into one new HDR file?

--
Johan W. Elzenga johan<<at>>johanfoto.nl Editor / Photographer http://www.johanfoto.nl

Good point and good question?

R

"Johan W. Elzenga" wrote in message

Hebee Jeebes wrote:

He wants to take two 32-bit HDR images and combine them in to one. Basically
what he wants it to use the two HDR images in Photoshop's merge to HDR as the source files.

Yep, that is clear. But what's the point? Those 2 HDR images must have come from merged originals, so why not merge those two sets of originals into one new HDR file?

--
Johan W. Elzenga johan<<at>>johanfoto.nl Editor / Photographer http://www.johanfoto.nl

Bart van der Wolf schrieb:

Do you want to blend them, combine parts of them, make a montage? That cannot be done. You need to change their mode to 16-bits/channel to do that. Or, if the HDR images were created by merging LDR images, maybe you could blend the LDR image components and then merge into an HDR image.

Well I made 2x3 bracketing images. I tried to combine the 6 images into one. I had no tripod, and somehow the aligning function didn't work correctly. So I made 2 HDR images (á 3 images) of it. That worked fine. So and now I want to merge the 2 HDR images. Of course, not by adding the luminance values ;-)

Do you now understand better?

Chris.

Hebee Jeebes schrieb:

He wants to take two 32-bit HDR images and combine them in to one. Basically what he wants it to use the two HDR images in Photoshop's merge to HDR as the source files.

You got it, Hebee!

Johan W. Elzenga schrieb:

Hebee Jeebes wrote:

He wants to take two 32-bit HDR images and combine them in to one. Basically what he wants it to use the two HDR images in Photoshop's merge to HDR as the source files.

Yep, that is clear. But what's the point? Those 2 HDR images must have come from merged originals, so why not merge those two sets of originals into one new HDR file?

[ x ] It didn't work.

So I'd like to make a step in between.

"Christian Drewing" wrote in
message SNIP

Do you now understand better?

So all 6 images are of the same scene, but due to mis-registration (caused by handheld exposures, and/or object movement) Photoshop can't manage to complete the merge.

What I'd try in a situation like that, is to do some prior alignment. Photoshop's alignment attempt seems rather finicky, so it might work better if you manually reduce the differences in hor/ver alignment. If you use simple single pixel shifts on a temporary 6 layer version of your shots in difference blending mode, e.g. with the offset filter, or the move tool and the arrow keys, all that's left for Photoshop is rotation and/or sub-pixel alignment.

Maybe that is still too difficult for Photoshop (its alignment or registration capability is in its infancy), in which case you could leave the alignment bit to better tools. You could either use tools for panoramic stitching, or a dedicated tool for HDR creation such as Photomatix (http://www.hdrsoft.com/). The trial version allows to align and create an HDR. It also has a tonemapping tool (with watermarking) that has come a long way since its earlier attempts.

Maybe Photoshop CS3 will do a better job than the current implementation, we'll have to see.

--
Bart

On Mon, 14 Aug 2006 20:23:47 +0200, (Johan W.
Elzenga) wrote:

Yep, that is clear. But what's the point? Those 2 HDR images must have come from merged originals, so why not merge those two sets of originals into one new HDR file?

Took the words from my mouth

Christian Drewing wrote:

Bart van der Wolf schrieb:

Do you want to blend them, combine parts of them, make a montage? That cannot be done. You need to change their mode to 16-bits/channel to do that. Or, if the HDR images were created by merging LDR images, maybe you could blend the LDR image components and then merge into an HDR image.

Well I made 2x3 bracketing images. I tried to combine the 6 images into one. I had no tripod, and somehow the aligning function didn't work correctly. So I made 2 HDR images (á 3 images) of it. That worked fine. So and now I want to merge the 2 HDR images. Of course, not by adding the luminance values ;-)

Do you now understand better?

Yes, but I doubt that it would work anyway. If Photoshop can't align those six images, why should it do any better with two HDR versions of the same six images? The problem is in the images, not in Photoshop.

--
Johan W. Elzenga johan<<at>>johanfoto.nl Editor / Photographer http://www.johanfoto.nl