Tag: chromatic aberration

Sunrise in Waterfront Park

Looking east from Waterfront Park near the University of Louisville Boat House
Sunrise in Waterfront Park

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As Hurricane Isaac moved north on Saturday I headed for Waterfront Park to capture what I hoped would be a dramatic sunrise. Isaac came past Louisville Saturday from the southwest. As a result most of the clouds were still off to the west of Louisville and the edge of the storm was just coming into Louisville early Saturday. This gave me an opportunity to photograph a rather dramatic sky before the body of the storm settled in north of Kentucky across central Indiana.

Instead of using my entire bracket set for this image I decided to try using the +2, 0, and -3 Exposure Values, three exposures instead of the six I shot, to see if I could produce a realistic HDR image. I found that doing this really lightened the load on my iMac processor and markedly speeded up the merging process in NIK HDR Efex Pro 2. My iMac is at a disadvantage when using the latest software because the GPU is too weak for some software to use so all processing must be done by the CPU. It doesn’t affect the final images but it does slow down my processing time considerably if I must use all images in a bracket set.

I noticed some Chromatic Aberration in the trees so I employed the Chromatic Aberration feature in NIK HDR Efex Pro 2 and removed a purple fringing that was occurring in the image. I used the Deep 2 preset in NIK HDR Efex Pro 2 to tone map and adjust the tonality before returning the image to Aperture 3 for final processing. The rental Nikon D90 I’m using has a lot of spots on the sensor but since it isn’t mine I’m not taking any chances of damaging it by attempting to clean it. Instead I must go over each image with a fine tooth comb looking for sensor spots. Aperture 3 does  good job of removing these spots when I use the Retouch tool Spot and Patch feature. It is tedious work and I’ll be happy when my camera is back from repair, fresh and clean, and in proper working order. I also adjusted the Vibrancy and Sharpened the image before exporting it for the web.