Some pairs of adjacent pixels on the NASA/JPL image which are of the similar/same values are rendered by Hoagland with different values.

Some pairs of adjacent pixels on the NASA/JPL image which are of different values are rendered by Hoagland with similar/same values.

Notice that the light pixel in the lower central dark area in the NASA/JPL image is made dark in the Hoagland image. The pixel diagonal upwards and to the right of the lighter pixel has a darker value, yet is rendered significantly lighter in the Hoagland image.

The checkerboard patterning is not present in the original. The partial matching of the checkerboard pattern with the shades of the pixels in the original image is most likely simply a function of probability.

The sum of all these differences indicates that the data has not simply been enhanced, but rather, changed. This indicates to me that the data in the Hoagland image is inconsistant with the data of the source image from NASA/JPL.

And of course, the Hoagland image has been severely blurred and grainified.

Technical Notes:

The original NASA/JPL image was cropped and increased in size by 900 % in order to approximately match the size of the Hoagland image. It was then layered on top of the Hoagland image and aligned to a close match using reference pixels which seemed to match—since the Hoagland image is so blurred and darkened this match is not perfect—it was the best fit possible without knowing Hoagland’s processing methods.

The images were saved to TIF format from PhotoShop and put into the GIF animation format using GifBuilder 0.5.2. The palette was 256 greyscale shades and GifBuilder removed the unused palette shades. This is not a perfect process, the Hoagland image has had a slight reduction of constrast and slight darkening as a result of conversions between formats (this does not appear to be the case on my Mac), but the data is consistant enough with both sources to make a comparison valid in my opinion. I invite you to do the same if that is not sufficient in your judgement.

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