HDR Processing- Initial Thoughts.

[CT]

I've been playing with the evaluation version of Photomatix off and on for a while and thought I'd post my thoughts on it as HDR seems to be increasingly popular. Don't consider this a 'How to' by any means, I'm very much at the experimental stage.

I just nipped out and took this shot... well two shots actually, one exposed for the foreground and one exposed for the sky

Both shots were hand- held and should really have been taken on a tripod. The software does a fair job of aligning the two images for you, but there are limits obviously and there was a slight breeze, hence some of the blurred foliage.

You can either use Photomatix to just combine the two images, or to generate a HDR image from the two shots, which I've done here. The result initially looks awful, but don't panic, you now need to apply tone mapping to bring out the best of both images in the one shot. There are a few sliders to control at this point, but it's not rocket science and the software largely does a good job anyway, producing an image with a huge tonal range, but looking usually rather flat. You can now make contrast and other adjustments to your HDR image within the software, but the options are rather limited and I've tended to save the shot at this point and make final adjustments in PSP. I don't profess to be any authority at all on this and it's just the way I've taken to working with it.

It's an impressive technique without a doubt, but I think you need to be restrained in it's application to avoid some of those HDR images which look more like a cross between a painting and a computer generated graphic, unless that's the effect you want of course, and it isn't always an unpleasant one. Over-sharpening definitely seems to me to increase that tendency.

I've tried to be restrained in the shot above. It looks a bit surreal maybe, but the subject matter contributes a lot to that I think. It's definitely a useful technique, and I would think it's a boon to the landscape people. I might even buy it, but having seen the price, I'll have to think about that.

 

[Boon]

i have just tried using photomatrix with 3 tiff shots i did especially for it, total load of crap i'm afraid, got a much better result when using only 2 images, although being handheld, they didn't line up correctly.

 

[CT]

Did you do the tone mapping Steve? That needs to be done off the same drop down menu as Generate HDI. You should end up with a better looking image which is just a bit flat. looking.

I save the image at that point - open it in PSP and adjust for pizzaz!

Or....try finding a suitable image.. a jpeg if you like. Open it in PSP or CS2 and save it as a Tiff to somewhere handy. I use the desktop. Once saved ,drop the brightness of the image by a stop or two and save that as a separate TIFF.

Undo the brightness change in your jpeg, then up the brightness by a stop or two and save that as your third TIFF.

Open Pixmantic. Open your three images and try processing those. Tell us what you get.

 

[Bachs]

Had a play with Photomatics myself today.
The sky on this one was either blown or the foreground was in deep shadow.

The idea is supposed to be bracket the shots on-camera but you can still get a decent enough range from RAW exposure edited shots to save an image from the bin.

The blending of 2 images exposed for sky and foreground would have been a masking headache on this one...I edited 5 shots in the RAW editor at different exposure levels, combined them then went to 'tone mapping' and pulled in the sliders on the histograms.

The result was pretty unimpressive...it turned a nice blue sky into a murky blue-grey and the whole image was very flat tonally.

The tricks I used were to selectively reduce saturation (hue/saturation, select specific colours instead of using 'master'), added an s-curve to boost contrast.
Still wasn't impressed.

What worked for me was to go back to the original shot in the RAW editor, pick the best exposure level I could showing some of the sky detail and foreground detail, added this into it's own layer above the HDR'd layer and changed the blend mode to 'pin light' and adjusted that layers' opacity until I was happy.

 

[CT]

I must admit I have trouble with skies in Photomatix. As you say though Bachsy, there's always more than one way to skin a rabbit.