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Jonesgj
7th November 2009, 12:57 AM
All,

If you use a program, for example like Photoshop CS or photomatix, to create a HDR image how do retain the original Exif?

I seem to have problems even with just reducing images and retaining the exif. Does anyone know about this or can offer advice?

Regards

Graydon

Nick Temple-Fry
7th November 2009, 01:15 AM
A lot of software has as an option save with exif (or exif-jpeg etc), so it's worth exploring the options on the dialogues.

But Photomatix seems to lose a lot of the data (and The GIMP loses all processing Tiffs)

However you can just copy your edited image (probably as a layer) and drop it onto the original - provided you then save with an exif option then you'll have the original data.

Nick

Jonesgj
7th November 2009, 01:22 AM
Thanks Nick,

I asked this thinking about how people could enter HDR shots into the proposed End Of Year Challenge with valid Exif data.

http://e-group.uk.net/forum/showthread.php?t=7075


Kind regards

Graydon

Nick Temple-Fry
7th November 2009, 01:38 AM
Well I've done it - just take your final image and copy it (in the GIMP as a layer) across an original (probably the 0ev for HDR) - that gives you the originals exif.

Sure it could be used to cheat, but if you retain the orfs (camera jpgs etc) the trail is clear enough.

Exif is hardly secure data, it's just a field in a data file.

Nick

Jonesgj
7th November 2009, 07:55 AM
Okay Nick, I'll try that. From what I know of layers etc it should work.

Kind regards

Graydon

snaarman
7th November 2009, 08:16 AM
All,

If you use a program, for example like Photoshop CS or photomatix, to create a HDR image how do retain the original Exif?

I seem to have problems even with just reducing images and retaining the exif. Does anyone know about this or can offer advice?

Regards

Graydon

Yes, I was struggling with exactly the same problem recently. I have just upgraded to CS3 (which I very reluctantly admit is worth the money...) and have therefore just started to play with HDR.
As you say, it does strip the exif, presumably because there are several exifs to choose from. So, as Nick suggests, load one of the original jpeg images, save the HDR jpeg as a layer on the top. Flatten it and in theory it should be the desired image but with the exif from one of the originals..

*Edit*
OK - I just tried this and it does work...


Pete

theMusicMan
7th November 2009, 04:10 PM
The question to ask yourself is...

If you took a series of 5 exposure bracketed images, what EXIF aperture would you choose to show for the resulting tonemapped image...?

Nick Temple-Fry
7th November 2009, 04:27 PM
The question to ask yourself is...

If you took a series of 5 exposure bracketed images, what EXIF aperture would you choose to show for the resulting tonemapped image...?

Well the aperture should remain constant, the shutter speed will vary.

But yes the data would be a compromise

Nick

theMusicMan
7th November 2009, 04:28 PM
Ahhh sorry.... I meant what Shutter Speed would you choose to display.