ChrisEdu Posted August 28, 2011 Share Posted August 28, 2011 Not sure if this is the right place to post this, so please move if deemed more suited to elsewhere.I have just been trying to take some photos of Jupiter, simply using my Nikon and 70-300mm lens. I have noticed though, when looking at the photos taken in succession, there appears to be an object that was not visible to the naked eye moving across the sky below Jupiter.The object appeared to be moving steadily across the sky, heading south, between Hip12832 and Hip12828 and was in photos taken between circa 2.30 and 2.50am (the period I was taking them).Any ideas? I'll try to post the photos later. Link to comment Share on other sites More sharing options...
ChrisEdu Posted August 28, 2011 Author Share Posted August 28, 2011 Edit to my intially post: Having looked again at the photos, the object actually appears to be heading northwards (from right to left) and at a slight angle. Link to comment Share on other sites More sharing options...
lukebl Posted August 28, 2011 Share Posted August 28, 2011 Pictures, pictures! Link to comment Share on other sites More sharing options...
brantuk Posted August 28, 2011 Share Posted August 28, 2011 Sounds like a satellite from the description, but photo's would help nail it down Link to comment Share on other sites More sharing options...
ChrisEdu Posted August 28, 2011 Author Share Posted August 28, 2011 Pictures are coming!Just transferred them from the camera.Having another look, the object appears to be a bluey/green hue. Link to comment Share on other sites More sharing options...
ChrisEdu Posted August 28, 2011 Author Share Posted August 28, 2011 Here are some photos: Link to comment Share on other sites More sharing options...
lukebl Posted August 28, 2011 Share Posted August 28, 2011 I'd say it was almost certainly internal reflections within the optics, I'm afraid. Link to comment Share on other sites More sharing options...
ChrisEdu Posted August 28, 2011 Author Share Posted August 28, 2011 One more from a wider view, one as taken and one tweaked to turn down the brightness and up the contrast. Got a nice streak on the right hand side in this one. Link to comment Share on other sites More sharing options...
brantuk Posted August 28, 2011 Share Posted August 28, 2011 Orbview2 (Seastar) came over past Formalhault at 2:45am from the South heading North West'ish - that's my best guess - but you could have caught a Comet - dunno where Gerrard was at the time? Link to comment Share on other sites More sharing options...
ChrisEdu Posted August 28, 2011 Author Share Posted August 28, 2011 I'd say it was almost certainly internal reflections within the optics, I'm afraid.What, do you think maybe relection of Jupiter? In other photos that I took, e.g. of Pleiades there is no sign of the 'thing'. Link to comment Share on other sites More sharing options...
ChrisEdu Posted August 28, 2011 Author Share Posted August 28, 2011 One thing I will say, I can see how easily people can get sucked into the world of imaging! It is cool seeing things you can't see! I just need to learn how to do it with my Nilkon and lens to start with. Any advice gratefully received, or pointers to where I can find out more! I was using a Nikon D300 with the 70-300mm lens and exposures from 2.5-30secs at various ISO speeds. Link to comment Share on other sites More sharing options...
ManInTheMoon Posted August 29, 2011 Share Posted August 29, 2011 Its its... its... a flying saucer! either that or its a naked Jupiterean streaking past your camera. Link to comment Share on other sites More sharing options...
ChrisEdu Posted August 29, 2011 Author Share Posted August 29, 2011 Well, whatever it was, I couldn't see it last night, neither could Swamp Thing! Link to comment Share on other sites More sharing options...
lukebl Posted August 29, 2011 Share Posted August 29, 2011 I still say it's a reflection in the optics. Very common when you get something really bright in the field of view, like Jupiter. Link to comment Share on other sites More sharing options...
swamp thing Posted August 29, 2011 Share Posted August 29, 2011 Well, whatever it was, I couldn't see it last night, neither could Swamp Thing! :)Yeah, thanks for the Goose chase Chris.Regards Steve Link to comment Share on other sites More sharing options...
ChrisEdu Posted August 29, 2011 Author Share Posted August 29, 2011 Yeah, thanks for the Goose chase Chris.Regards SteveYeah, I think you were out by a few inches! Eh, Pingster?! Link to comment Share on other sites More sharing options...
ChrisEdu Posted August 29, 2011 Author Share Posted August 29, 2011 I still say it's a reflection in the optics. Very common when you get something really bright in the field of view, like Jupiter.Would that explain the apparent movement across the field of view though?If it is clear tonight, I shall have another go at recreating the same set of conditions and see what happens.I have experienced what I'd imagine to be internal reflection from the Moon on long(ish) exposures and found that they went with short exposure times. Link to comment Share on other sites More sharing options...
rfdesigner Posted August 29, 2011 Share Posted August 29, 2011 I've had exactly this defect.The refection is often a mirror around both axis.. it's location is bang on for this type of artifact. I've seen it in my camera with a bon fire and the reflection was inverted.. It will only usually show up in images where a significant overexposure is seen.. as in this case. in your Pleiades case the overexposure will be much less as the maximum brightness is 3.7, where as Jupiter is now at -2.6, that's over 6 magnitudes brighter (well over 100 times as bright).. have a VERY careful look (compared with a 180 degree rotation image) and you will probably see a faint Pleiades artifact.hope this helpsDerek Link to comment Share on other sites More sharing options...
lukebl Posted August 29, 2011 Share Posted August 29, 2011 ...Would that explain the apparent movement across the field of view though?...Yes. I've had similar effects to the phenomenon you've described and it also appeared to move, presumably because the distance from the reflection to the object changes depending on its position in the frame.Trust me. It's a reflection! Link to comment Share on other sites More sharing options...
ChrisEdu Posted August 29, 2011 Author Share Posted August 29, 2011 Ok - I've just been having a look at some of my previous over exposed Moon shots and can see something similar, with the same colouration. I think it's looking pretty likely that internal reflection is the answer. I guess, the apparent movement across the sky would be explained by Jupiter's apparent motion from north to south then being reversed by the reflection, hence the south to north movement.Thanks for the help, chaps. I guess the answer would be to use shorter exposures next time? Would Registax be suitable for processing such exposures? If so, could someone please point me towards a simple 'How to'? Thanks. Link to comment Share on other sites More sharing options...
lukebl Posted August 29, 2011 Share Posted August 29, 2011 Not sure there's much you can do about it. Even high-end equipment struggles when there's something really bright in the field of view. For example, imaging the Horsehead and Flame nebulae in Orion can be a problem due to the bright star Alnitak nearby causing reflection problems. Link to comment Share on other sites More sharing options...
ChrisEdu Posted August 29, 2011 Author Share Posted August 29, 2011 Well, I have found that reduced exposure times worked when photographing the Moon. At first, with that, I was really bemused, having not encountered the issue in my 'normal' photographic work. Would this be likely to happen if I used a T-mount to attach my camera body to the scope? I'm assuming it wouldn't, as there'd be no camera lens. Link to comment Share on other sites More sharing options...
rfdesigner Posted August 29, 2011 Share Posted August 29, 2011 I've had the problem in at least 3 different lenses, a praktica B, a carl zeis and now my latest canonI've never had it in a scope, but then I use Newts.. With multielement refractors I would want to check them out for this.Derek Link to comment Share on other sites More sharing options...
Pingster Posted August 29, 2011 Share Posted August 29, 2011 Hahaha! Thats a really odd image, i would dare say UFO, but maybe optics reflection.Anyway from our experience yesterday... theres no way you will get to recreate the image as i am sure you have no idea which part of the sky top look. If it helps i think it was somewhere south... maybe 40inches below Jupitor and say 5cm to the left. Hahahaha Was a hilarious night of viewing! I really enjoyed yours and Swamp Things Company. I sure won't want to go alone so often.The highlight of the evening was comet Gerrad, now i understand my Messier created his list. It sure looked like either a neb or galaxy.Shame the seeing was so bad, i am sure the sky there will be much better with good seeing. I hope next time we meet up the moisture content is in the 80's. Link to comment Share on other sites More sharing options...
ChrisEdu Posted August 29, 2011 Author Share Posted August 29, 2011 Hahaha! Thats a really odd image, i would dare say UFO, but maybe optics reflection.Anyway from our experience yesterday... theres no way you will get to recreate the image as i am sure you have no idea which part of the sky top look. If it helps i think it was somewhere south... maybe 40inches below Jupitor and say 5cm to the left. Hahahaha Was a hilarious night of viewing! I really enjoyed yours and Swamp Things Company. I sure won't want to go alone so often.The highlight of the evening was comet Gerrad, now i understand my Messier created his list. It sure looked like either a neb or galaxy.Shame the seeing was so bad, i am sure the sky there will be much better with good seeing. I hope next time we meet up the moisture content is in the 80's.'Twas indeed a good evening. Fun gazing and a good laugh! We'll have to arrange a power cut for the Sussex coast for next time! Link to comment Share on other sites More sharing options...
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