Problem with tonemapping

[Hansiboy]

I start "Merge to HDR Pro" in CS5 with at least 3 Raw images. When I am finished making adjustments according to what I like (in 16bit), I click the OK button. But the resulting converted HDR image does not look like its preview in the Tone Mapping Dialog. The result is far too saturated and darker. Is there anything I can do to avoid this. Thank you.

[Colin Southern]

I'm not sure why it doesn't match the preview, but in general, all colours will saturate more as you lower tone value (up to a certain point beyond which it just starts looking darker and darker). Don't forget though that an HDR merge isn't a final solution in itself - it merely gets the image to a point where nornal post processing can start ... so just lower the saturation and make other adjustments from there.

Hope this helps

PS: Any chance of a first name?

[Hansiboy]

Thank you Colin for getting back to me. My first name is Hans. Sorry I did not introduce myself properly.

Of course I can make adjustments afterwards, but somehow it bothers me that the result of the Merge to HDR Pro is totally off from the adjustments I made in the preview panel. Anyway I have been doing some tests and I found out that I can work around this issue by selecting the 32bit conversion. Once back in PS I change the Image Mode to either 16 or 8 bit. This opens the normal HDR Toning Panel. I make the adjustments I have in mind and after clicking OK the converted image looks exactly the same as the preview. Or, and this is even more surprising, when I decide to go for a 16 bit version from the beginning when launching Merge to HDR Pro, after I click OK, the conversion runs, but I cancel the conversion during this process. I end up with a 32bit HDR image (which shows totally black in the Layer Pallet). Then I bring the Image Mode to either 16 or 8 bit. This opens the HDR Toning Panel. I adjust whatever I want to adjust, click OK and ... yes, the result is exactly as the preview.

Here is another example of the same issue.

Cheers,

Hans - http://www.flickr.com/photos/h_vinck/

[Colin Southern]

Hi Hans,

Keep in mind that an HDR image may have captured 12 or more stops of dynamic range - but your monitor will only be able to display around 6. So with a true 32 bit HDR image the internal representation of that image - and how that internal representation is able to be displayed - may be vastly different.

Personally, I wouldn't lose any sleep over it - one way or another it's something you'll need to adjust anyway.

[proseak]

I use "Merge to HDR" quite a lot and regard it as merely the first step in generating the image - I prefer to do my adjustments in either ACR or PS and sometimes both. My preferred settings in "Merge to HDR" are to use one of two presets - either "Flat", or "Photorealistic", with the radius set to 1. Then save as 16-bit Tiff and import to ACR. There, I set the blacks rather heavily, and use fill light to open up the shadows. Quite a lot of Clarity to "up" local contrast, and Vibrance to suit. Usually not much to do in PS at that point, except perspective control and output sharpening.

HTH

Peter

[Hansiboy]

I use "Merge to HDR" quite a lot and regard it as merely the first step in generating the image - I prefer to do my adjustments in either ACR or PS and sometimes both. My preferred settings in "Merge to HDR" are to use one of two presets - either "Flat", or "Photorealistic", with the radius set to 1. Then save as 16-bit Tiff and import to ACR. There, I set the blacks rather heavily, and use fill light to open up the shadows. Quite a lot of Clarity to "up" local contrast, and Vibrance to suit. Usually not much to do in PS at that point, except perspective control and output sharpening.

HTH

Peter

Hi Peter,

Before you save to 16bit-Tiff do you start "Merge to HDR Pro" in 32bit, use a preset and then press OK? From then on do you change the Image Mode in PS to 16Bit and save the result as a Tiff-image, after which you open the file in ACR?

Thank you,

Hans

[Hansiboy]

Hi Hans,

Keep in mind that an HDR image may have captured 12 or more stops of dynamic range - but your monitor will only be able to display around 6. So with a true 32 bit HDR image the internal representation of that image - and how that internal representation is able to be displayed - may be vastly different.

Personally, I wouldn't lose any sleep over it - one way or another it's something you'll need to adjust anyway.

Hi again Colin,

Much obliged for your time. Though I am not losing any sleep, I have to admit that it keeps me busy a lot . Mainly because I watched and studied different instruction video's from Russel Brown and Julieanne Kost where the issue that I mentioned does not happen. What they see in the preview is pretty much what they get after converting. But okay, I can live with my situation, for indeed, the HDR procedure is just one step and the final touches have to be done separately.

Greets,

Hans

[proseak]

Starting in Bridge, I select the images, then Tools>Photoshop>Merge to HDR Pro. After the preview is "up", chhose "Flat" from the presets, and click OK. It then opens in Photoshop as a 16-bit image, "Untitled_HDR2".Now, Save as 16-bit Tiff(I name it after the first image in the sequence), and close. Then open in ACR.

HTH

Peter

[Hansiboy]

Hi everybody,

I am very relieved to announce that I discovered the reason why my converted HDR images completely unmatched their previews. The solution is to be found in the settings of the ACR Workflow Options. My bit-depth was set to 8-bit in ACR. Changed it to 16-bit et voilà: problem solved

[proseak]

Hi everybody,

I am very relieved to announce that I discovered the reason why my converted HDR images completely unmatched their previews. The solution is to be found in the settings of the ACR Workflow Options. My bit-depth was set to 8-bit in ACR. Changed it to 16-bit et voilà: problem solved

That's a relief, Hans - I was going to suggest checking your Display Settings, and making sure that they were set to 32-bit.

Look forward to seeing some of your pictures!

[Hansiboy]

Hi Peter,

Still working on HDR tone mapping, but hereby I can give you an example of my efforts, based on 3 different exposures. The images were taken around sunset. At that time of day yesterday the wind had fallen, and of course, the soft light of the setting sun was excellent. I tried other similar shots earlier during that day, but the wind made it too hard to meet my goal. Even a slight breeze moves the plants, which is really not what you are looking for when shooting close-ups or macro in order to use them for tone mapping.

[proseak]

"Even a slight breeze moves the plants, which is really not what you are looking for when shooting close-ups or macro in order to use them for tone mapping." -

I do know what you mean - it's one of the main reasons that I prefer to photograph buildings!