Comments on: Wallpaper: Iapetus Bright Portrait

By: Gordan

Gordan — Fri, 14 Sep 2007 22:44:11 +0000

Mostly manpower/funding I think. Though the Voyager dataset is not as easy to calibrate due to vidicon tubes - they distort the image geometrically so they need to be corrected, hence those reseau marks were placed in the optics. There were also apparently some other problems with calibration and it’s being worked on slowly.

By: thomas

thomas — Fri, 14 Sep 2007 20:27:41 +0000

oh my… voyager? that took a lifetime. is it manpower they lack or is it that hard?

By: Gordan

Gordan — Fri, 14 Sep 2007 14:47:28 +0000

No, the raw page states wrongly, only full quality raw data is released to the PDS after 9 months, not calibrated data. Calibrated data might come after the end of the mission. Voyagers for example just recently got their Saturn flyby calibrated release.

By: Gordan

Gordan — Fri, 14 Sep 2007 14:43:40 +0000

That image is a colorization of a grayscale image using color from their north hemisphere shot. That shot was in turn composed of IR/green/blue IIRC so it’s more saturated (more red) than in reality. Here are my processings of calibrated data that should be closer to natural color: http://img209.imageshack.us/my.php?image=iapetustw3.jpg

By: thomas

thomas — Fri, 14 Sep 2007 14:25:14 +0000

i linked to the older “dark” side image and from what i recall that is a NASA image. seems much more brown than what these images gave us. all the images in raw always say that they will be calibrated… is there somewhere to see the calibrated images when they get done?

By: Gordan

Gordan — Fri, 14 Sep 2007 08:09:55 +0000

I was absolutely exhausted after finishing this one. The black & white version was done fairly quickly, but processing an additional 45 frames for color was tedious.
I wonder if (and when) CICLOPS will release a natural color mosaic or just the IR/G/UV stretched color one. It would be interesting to see how off I was in brightness and color, compared to calibrated data.