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Back from hols Posted on August 14, 2008
Free Adobe Lightroom Posted on July 16, 2008 1 comment (latest 15 months ago)
Getting to grips with HDRShop - tonemap 2 comments (latest 16 months ago)
Inspiration from odd places Posted on June 19, 2008
Beach huts Posted on June 18, 2008
Alone with 2 children on a bank holiday weekend in the UK Posted on May 26, 2008
HDRShop Posted on May 12, 2008 1 comment (latest 18 months ago)
Hesdin Posted on May 9, 2008
Your help please Posted on May 8, 2008 4 comments (latest 18 months ago)

Getting to grips with HDRShop - tonemap

Wednesday July 2nd, 2008 at 02:29PM

As you will know, I have a copy of HDRShop. What I can't get anyone to give me is any pointers on what to do when.......

So it looks like I will just have to do it myself and leave hints for future generations later. I started with a raw file which I converted in to seven JPG files in 1 stop steps from

My lowest available stop

blown highlights

I have a camera specific gamma correction curve which I used because I don't want to go second guessing this stage yet.

So on to tonemapping - using the plugin defaults you get a very grainy "over-exposed" image with lots of colour noise. I took this to mean the luminesence was too high for the software to cope. So I adjusted the key value lower until I reached a satisfactory level (0.01). I also lowered the integer on sharpening to 4 to reduce some of the noise.

night scene HDR test

So there we have it key controls overall brightness (exposure) of the final tonemapped image (low darken - hi brighten) and Phi controls the sharpness (low integer no sharpening).

2 Comments / add your comment?

Roberto Ballerini - traveling^pro says:

In my opinion, using the same shot to generate different exposures isn't the right way to go: you will be limited by the number of bits your sensor can manage, i.e. its static range.
Use a tripod and make different manual exposures (eventually using the bracketing function of you camera): you will have the same static range, but centered on different exposures, and the HDR app will be able to combine them using luminance and chrominance informations from the different shots.
The only problems with this approach are ghosting, objects moving from exposure to exposure, and camera shake (use a tripod!)

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Seen in robertoballerini home page (?)

Posted 16 months ago. ( permalink )

All that remains replies:

Thanks for the advice Roberto - this was more an exploration of the functions of the software than a genuine attempt at a whole picture. I think you are right there are situations where a much wider range of RAW exposures are required. This being one, but even so the 8 stop range of recorded data in a RAW file does provide an awful lot more detail than is used at a single exposure JPEG. With the added advantage of no ghosting :) I think when it gets darker again I will be out seeking these shots more and probably I will be looking for the ghosting as part of the image.

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Seen in aspire2hope home page (?)

Posted 16 months ago. ( permalink )