Nik HDR Efex Pro Info

On November 5, Jim Smith from Sun City West presented an HDR Workshop at our classroom.  There were nearly 50 people in attendance from our club and other area clubs.  Jim gave a very detailed and informative description of what can be done to digital images using HDR software, specifically HDR Efex Pro.  He had numerous images that showed the before and after using the software.

This was the first time I had tried to use Nik HDR Efex Pro and I was impressed with the program.  I have been mainly using Photomatix but liked the Nik program with all the presets, the before/after screen, and the control points where you can make a number of localized changes instead of the whole image.  I did not see the capability to do batch processing like Photomatix (where I can take a number of multi-EV shots at an event, process one set to get a desired HDR effect, then use that same setting to do the rest of the event shots and let it run for a couple of hours til completion).  I also have read other comments that Photomatix has better ghosting and noise reduction.

All in all, Nik HDR Efex Pro is a very good program and I feel that a lot of our SIG members would prefer it.  It would be interesting to have a number of Nik vs Photomatix demos and comparisons done as part of our future SIG meetings.  Both programs are currently available for $80 using the discount codes on our blogsite (at the tab labelled: 2. Software Info).

Jim prefers working with jpeg images, and demonstrated using HDR Efex Pro both on multiple and single exposure images.  This brings up a number of points that we have been discussing during our SIG meetings:

1. The sensor in our digital camera is capable of producing a dynamic range greater than can be displayed on a monitor or a print.  They can deliver a 12 bit image (over 4,000 tonal values) vs an 8 bit image (256 tonal values) normally associated with a monitor or print.
2. A RAW image will preserve the 12 bit range while a jpeg compresses it down to 8 bits.  Therefore there will be a higher dynamic range captured in a RAW image vs a jpeg.  This is especially beneficial if you are working with a single image.  A multi-EV jpeg set, however, can produce a very good HDR image.
3. The interesting effect you get from processing a single image jpeg in an HDR program comes from the tone-mapping feature in these programs.  It is not an HDR image but is a tone-mapped image.  Tone mapping changes the tonal value of the pixels in an image with respect to their surrounding pixels.  This results in more contrast within clusters of pixels and makes the image "pop".
4. True HDR images are created by blending together multiple EV range images that will get rid of the "goal posts" in your histogram.  However, the problem then is that no monitor or print can handle this range, so the program then goes the next step to compress and tone-map it back to a range that can be displayed.  But the result sure looks better to our eyes than a single "goal post" image.

This is my understanding of the HDR process.  It's always interesting to compare this with what other people are discovering by their research and experimenting.  That's what makes our HDR SIG so great.  We can all learn and exchange info with others in our group and all benefit from the result.

Speaking of making photos "pop" here is a link to a video that Elisa Morris sent to me about fixing blurry photos:  http://tv.adobe.com/watch/max-2011-sneak-peeks/max-2011-sneak-peek-image-deblurring/

Bill Graczyk