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Originally Posted by gregbradley
1. If it were a bright star and the scope slewed it would have left a straight trail and not a wiggly trail. Try it. Also it would have had to
be a few seconds still and then slew as the bright ball would not have exposed hardly at all otherwise.
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Although I don't have a GEM (yet, one on the way), I have observed that when they start to slew they start slowly then speed up. Is this the case for an EQ5? I don't know, perhaps someone with one can confirm this?
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2. There are trails in the background that are not parallel. If it were trails from an accidental slew these would have been parallel not at different angles. Looks like he caught a few in the background. Maybe fragments?
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If it's slewing in both RA and Dec then the trails won't be parallel, as the scope may be moving at different speeds in each direction, That's what my RCX does, it slews each axis independently.
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3. Hot pixels don't look like that or at least not in DSLRs I have used. There usually aren't that many and they aren't different brightnesses as much as those are. They look like underexposed stars. If his camera has that many hot pixels it may be time to get a new camera!
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The bright spots don't fit a stellar profile, if you look at the intensities of the spots, the go from 0 to 128ish to 255 over three pixels, there are only 256 levels in an 8 bit image, so that's 0 to half full to full. That's pretty much what I'd expect from the conversion from RAW to Jpeg in camera for a colour CCD. The bright spot in the middle doesn't do this, it pretty much shows a gaussian profile until it gets saturated.
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4. I wonder if it was space junk or irregular in shape and perhaps tumbling.
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Perhaps, but that isn't a meteor, and why the bright spot in the middle?
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5. Meteor shots in a long exposure are a very common event. Not rare
at all in fact if you image 5 hours you will no doubt have at least several meteor trails in your images.
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Have to disagree with you on this one Greg, never seen one, seen plenty of satellites, no meteors, though I may have, but I would have thought a meteor trail would be especially bright if it was visible to the naked eye. There's heaps of times I spend many hours out at night and don't see any meteors at all. That may have something to do with light pokkution though.
I hope this answers your questions Greg. When I get my new mount I'll try and reproduce the photo, but I expect months of clouds.
Cheers
Stuart