originally posted by: terminationshock
Why are you trying to imply that if a third party (Google) uses actual NASA imagery, that it is somehow no longer valid as a source? Are you trying to
argue that they no longer visually represent the originals?
I'm not trying to imply any thing, but it's a fact that a compressed image mapped on a relief map and zoomed beyond 100% is never going to look as
good as the original.
Also, increasing contrast may (as it did in this case) remove the more subtle shades of grey in the image, creating something that really isn't
there.
Why would it have been "silly" to alter the viewing angle?
Because I was using Gimp and I would never be able to recreate the process used by Google.
Google Mars is set up to be viewed that way, so you can view the geological features and it works perfectly for that.
See above.
The images were also taken at an angle and not top down like you are trying to imply.
That's one of the reasons knowing the original image ID is important, as they have that data.
In photo's PSP_006005_1515 page we can see that the phase angle (the angle between the vertical of the centre of the photo and the camera) was 15.8°,
which means that the camera was pointing down at an angle of 74.2º, map when the image is map projected (like the one I used) that is taken into
account.
What point are you trying to make by using a top down view and and making "adjustments"? This technique works just as well on McMurdo Base in
Google Earth. Hey presto, it vanishes too!
My point is providing the best quality images we have instead of images in which some information was destroyed by your brightness and contrast
changes.
The adjustments I made did not remove any information from the images, as they were done keeping the minimum and maximum values between 0 and 255.
It would have been quicker if you had simply gone the traditional route and said it was "swamp gas".
I never said that in my life, I wouldn't say it regarding a Mars photo, where there aren't any swamps (as far as I know).
I haven't seen someone try to gaslight this hard in a long time.
Presenting real data and facts is not gaslighting.
You presented altered images in which some information was destroyed by the brightness and contrast changes, with no scale.
I presented the closest to the original data (the original data doesn't have any processing done, so it's not as good) I could and I added a scale.
You sure have a strange definition of gaslighting.
PS: do you still see the same things in the images I posted? If you do, what's you problem?