D800 vs. D800E Microcontrast

Started Feb 15, 2012 | Discussions thread
JohnWheeler
Regular MemberPosts: 135
Like?
Re: D800 vs. D800E Microcontrast
In reply to Kaj E, Feb 23, 2012

Hi Kaj

I think there could be lots of reasons that the D800 and D800E images look different including that the D800E is just sharper. There are many variables that come into play many of which have already been mentioned on this thread. If the crops were both not in the exact plane of focus would also make a difference. The background of the two images and crops are not well documented so hard to know. I agree with prior posts that good apples to apples will probably have to wait for independent testing. I was concerned that this particular image was generating a lot of excitement (and also buying decisions for the D800E vs the D800). The only other side by side comparison Nikon provided specifically to compare sharpness was the image with the stone pathway in the forest. That pair of images appeared to be at the same compression at least. The improved sharpness was noticeable yet much more modest than the Alpine image. Since higher JPEG compress can degrade the sharpness by a bit and the D800 image had higher compression, I thought it was worthwhile to raise the cautionary yellow flag.

As far as generating the Hue and Sat Channels. There are many sources (fee and paid) online that provide something similar. For me, I just use PS actions.

I am using the Adobe definition for Saturation which they use in their blending functions which is Result pixel= Max(R,G,B) - Min(R,G,B) and set all RGB values to the resulting value for each pixel. I just use the math in PS blends and adjustment layers to provide that result.

For the Hue channel the approach is very similar (jut use my own Action). The Hue is as defined by PS (and by many other sources) and I use blends and adjustment layers so that the original Hue of each pixel is set at Saturation of 1.0 (other values of Sat could be used yet I found this to give the best representation of just pure Hue). With Raw/uncompressed data you will not see the pixelization shown in the images found in the link I provided. I created those actions a few years ago for my own use primarily for mask creation. When I ran JPEGs through the same actions it just was an aha (and sort of obvious after the fact) that it also gave a feel for the level of compression used on JPEG (or other) images. The eye is most sensitive to luminosity changes and much less so to color changes. Ergo - why compression algorithms compress the color components much more than the luminosity components (that's a simplified statement compared to everything done for compression algorithms of images yet close enough for this discussion) Hope that helps

-- hide signature --

John Wheeler

Reply   Reply with quote   Complain
Post (hide subjects)Posted by
NupNew
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark post MMy threads
Color scheme? Blue / Yellow