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On 6/23/2013 12:53 AM, Greg Rudzinski wrote:
> HDR sounds difficult. Looking forward to seeing some examples.

Sadly my time has not been my own for the past 5 years. I have new
imagining software I've installed and had no time to play with.

HDR should not be difficult. There are plug ins and stand alone
software. Some of the new smartphones have it built in. They take three
bracketed exposures rapid fire, then process them into one image. The
obvious downside here is a moving subject.

There is at least one high-end Nikon SLR that claims to make the
multiple bracketed exposures simultaneously, so subject movement is not
an issue. The only way I can conceive of this is starting with one raw
image (a higher dynamic range than a JPG) an processing it to optimize
for shadows, mid tones, and highlights. The user can then combine those
images for an HDR image.

Note: For non-hardcore photogs, camera raw is the direct unprocessed
readout of the sensor array which the user later processes in his or her
electronic darkroom. By letting the camera process/compress an image
into a lossy format (jpg) a lot of useable information is discarded.

For those not familiar with HDR, it is a digital tone-mapping process.
It's very much like what Ansel Adams and other zone-system photographers
did by changing exposure and development to alter the contrast curve of
the negative. In printing they might "burn in" some areas to darken
them, and "dodge" others to lighten them.

Stand alone software can be had for as little as $1, with others at the
$100 price point. My Nikon D7000 can auto bracket, but three exposures
will take a half second (or more depending on shutter speed) and would
need to be tripod mounted. Which pretty much leaves me with lunars
unless I can re-purpose one raw exposure.

Of course sun observations are so off the chart, one would still have to
use Greg's filter tricks.

For a quick look at HDR "magic" including smart phones:

http://lifehacker.com/5991508/what-is-hdr-and-when-should-i-use-it-in-my-photos

Bill B

   

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