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Old 07-20-2009, 12:26 PM
Astronut Astronut is offline
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Join Date: Jul 2009
Posts: 41
Default Re: The Space Shuttle and the ISS are a Hoax!

Quote:
Originally Posted by galexander View Post
Astronut, the reason you give may explain why the ISS appears to drift to one side of the field of view only to be centred again each time but this is clearly not what is happening in your video. The image of the ISS is dancing around erratically and apparently at random.
Getting and keeping ISS in the field of view at an effective magnification of 400x is much more difficult than doing the same with saturn; one is flying across the sky at several degrees per second at its peak, the other is almost stationary. Add to that, the lag between issuing a command in the satellite tracking and seeing it reflected on the screen, and with my color camera the framerate is almost-slideshow-like and you get massive over-correction. It's moving "erratically" because I'm having trouble getting it to center properly. You also get hiccups when the computer pauses for a split second to process the tracking commands - that results in it dashing out of the field only to return a moment later, assuming I didn't react to the sudden motion and "correct it" out of the field. Again, you're trying to compare centering a celestial object like saturn to centering a fast-moving satellite where the controls are sluggish and the slightest mistake is devastating. Last, but not least, to increase stability I always mount the LX200 in alt-az mode when doing satellite tracking. As you should know, alt-az has the nasty issue of field rotation; not so bad for short planetary observations, but devastating to long exposure images. This also affects satellite tracking for the same reason; in different parts of the sky, "up and down" in the eyepiece will mean totally different things in terms of right ascension and declination. For satellite tracking, this means that pushing "up" on the joystick will adjust the apparent position of the satellite one way at the start of a pass, and a different way at the peak of a pass. If you're using less magnification like in the second video, this is acceptable as long as you have room to play with, for 400x it means you're going to look like you're adjusting it erratically. For my second video, however, I had a wider field of view at the equivalent of 200x and the motion of ISS is quite stable.
Quote:
As for titanium oxide having a bond energy of 458 eV (sic.) are you absolutely certain you didn't actually mean 458 kJ/mol? The two units are completely different. I wouldn't be surprised about the latter figure but certainly not the former.
Yes, I'm sure. It's 458 eV. See: Tatsuya Okubo et al (2005) Plasma Nitriding of Titanium Particles in a Fluidized Bed Reactor at a Reduced Pressure. Journal of the American Ceramic Society. 73(5) pg. 1150-1152
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