Recently, my website crashed. Don’t ask me how, but it’s my fault for using a free web hosting service (although I can’t hate on it too much, because it’s actually pretty good for being free). After spending some time going back and forth with the helpdesk, I was ultimately forced to restore my entire website from backups. Shouldn’t be a problem, right? Wrong-o. For some reason or another, my database was not properly backed up, meaning I lost a lot of data. Consequently, there are some things missing from the blog, but whatever, at least most of it was restored.
Anyway, this catastrophe caused me to comb back through my older posts, to get an idea of what was missing. In doing so, I noticed that my HDR post from last year was missing something crucial. However, the missing piece in question is not the fault of the bunk database backup, but rather my oversight when initially writing the post. So now I’m making an addendum to my HDR tibits post to add in this extremely important information.
What I forgot to address was the advanced options in Photomatix. In the left bar, under the main settings covered in the last tutorial are two buttons: “Show more options” and “Show advanced options”. Click both of these to expand.
By far the most important of these options are the ones labeled “White Point” and “Black Point”.
One of the things that tends to happen in HDR processing is that whites and blacks get lost in the photo as grays, or worse yet, are clipped. I’m not really sure how to describe the resulting picture, other than simply saying it lacks “punch”, if you know what I mean. Fortunately, white point and black point exist for the purpose of preserving whites and blacks in an HDR image, effectively saving them from the brink of gray.
In either case, moving the sliders to the right increases the white or black in the image, while moving them to the left decreases, respectively.
Another important slider is “Smooth Highlights”. This slider can be particularly useful if you’ve pushed the luminosity and lighting adjustments sliders in the basic settings to the point where you’re getting some haloing. Pushing the smooth highlights slider to the right can help to correct some of the haloing.
Moving down to the “Advanced Options”, the most important slider in here is the “Micro-smoothing”.
Micro-smoothing has a tendency to tone down some of the grit and noise inherent in an HDR image, and can be an important slider in perfecting the HDR effect. The further you push the slider to the right, the more it tones down the noise and grittiness, although this does come at the expense of some detail.
And as always, I import the final HDR image into Photoshop and usually layer it over the original image, which allows me to have an even greater level of control over how strong I want to HDR effect applied, and to which areas of the image.