Even if the meteor had a straight tail, from the evidence available, a scientist could not fully conclude it was actually a meteor.
There is always a possibility of it not being one. The wavy tail has only enlargened this margin.
Stuart needs to realise there is a point where scientific assesment needs to back off. If your right, your right, you should have enough confidence in your own assesment, to allow the debate to finish. This means not only to stop "baiting" for more info, but to actually disregard the "baiting" you are receiving.
Lets face it, if you were supplied with every bit of data to the event, you still could not confirm it as real. Therefore as hard as this may be, you can not disprove that is not a meteor.
Given that, I would assume the lighter path of, "I think not, but congrats if it is" approach a bit more site relevant... By all means in the eyes of science and given the correct environment, shread an image apart and reveal its flaws.
Maybe it is just me, but given the poster was not really claiming any fame, just posting an image, even if I knew the picture was a bit off, I still wouldn't smash the person down over it... Which is what you are doing, to someone whom doesn't work in this field.
On a side note, you do see to be almost "Trolling", as you know you are not is the same catagory of knowledge as the poster, your analysis has been posted, yet you still seem intent on pursuing this till the envitable end of
" OK, you right, it's not a meteor "...
Stuart needs to realise there is a point where scientific assesment needs to back off. If your right, your right, you should have enough confidence in your own assesment, to allow the debate to finish. This means not only to stop "baiting" for more info, but to actually disregard the "baiting" you are receiving.
I'm sorry, but when I see something that needs correcting I correct it. I'm not baiting for information, I'm genuinely interested in the outcome. Not to prove me right or wrong, but just to get to the bottom of it. I hate unresolved problems that I know could be solved simply.
Why should the debate finish, to my mind, and probably others, the question as to what Chris has photographed remains open. Healthy debate never hurt anyone.
Quote:
Lets face it, if you were supplied with every bit of data to the event, you still could not confirm it as real. Therefore as hard as this may be, you can not disprove that is not a meteor.
With the right amount of data (one more photograph) I could at least disprove my theory. The second sentence has a triple negative in it, I assume you mean that I can not prove that this is not a meteor. I never wanted to prove that this is not a meteor, I just wanted to be able to explain it in a ration manner.
Quote:
Given that, I would assume the lighter path of, "I think not, but congrats if it is" approach a bit more site relevant... By all means in the eyes of science and given the correct environment, shread an image apart and reveal its flaws.
I tried the lighter path and got flamed. I offered my opinion and got flamed. I suppose I should have not responded after my analysis was called into question?
Quote:
Maybe it is just me, but given the poster was not really claiming any fame, just posting an image, even if I knew the picture was a bit off, I still wouldn't smash the person down over it... Which is what you are doing, to someone whom doesn't work in this field.
I think the vast majority of us here are amateurs, not many would work in the field. I didn't "smash" Chris down, I merely pointed out that there is another explanation for the image. I was the one who was "smashed". I took it and still tried to respond in a calm and rational manner.
Quote:
On a side note, you do see to be almost "Trolling", as you know you are not is the same catagory of knowledge as the poster, your analysis has been posted, yet you still seem intent on pursuing this till the envitable end of
" OK, you right, it's not a meteor "...
So shoot me for being interested in the subject! I'm not trolling, I'm interested, I follow the postings in the forum and this thread closely as I'm interested. I try to impart what little knowledge (there are people on this forum with vastly more experience than I) I have, to others. It's called teaching and learning, again, something that never hurt anyone. The "inevitable" end to this maybe not possible, certainly not without some more pictures.
I still like the idea of meeting over a beer or two and going through the photos. Unfortunately I'm working over IISAC09, which is probably the closest I'll be to SE QLD for a while.
First: Stuart is not bullying Chris, he is offering his opinion as to what he thinks Chris' picture is, because to him, it DOESNT look like a meteor and he is explaining what HE thinks caused the picture.
Second: I have my doubts as to WHAT IS IN THE PICTURE! Simple. Just because I happen to agree with Stuart's analysis doesn't mean that I am correct EITHER. I also take offence to the belief that I am therefore effectively bullying Chris by agreeing with Stuart. Something which Stuart is not doing.
No-one is criticising Chris for what he is said or who he is or what sort of bloke he is, we are simply commenting on the picture, something I thought we are ALL allowed to do here?
To effectively state that "everyone else thinks it's a meteor, so SO SHOULD YOU" is just naive and sorry for this in advance, a little bit childish. I believe this because of the subsequent comments threatening to pack up, take your bat and ball and go home.....
It seems that the entire content of what I have posted has not been read or understood, but simply boiled down to an emotional feeling of "Screwdriverone thinks Stuart is right and Chris is wrong"
Obviously, the words, like "possibly", "believe" and "im my opinion" were translated to "you are wrong" in each case? Not ONCE have I said, you are wrong, you have not captured a meteor, because, quite frankly, I cannot rule out that you HAVE captured one!
For the record, I agree that Chris' picture of the meteor is PLAUSIBLE, Stuart's explanation of what is in the picture is ALSO PLAUSIBLE.
I, personally, think that by looking at the picture, what is captured, doesn't look like a meteor based on what I have seen. This therefore means that Stuart's explanation seems MORE PLAUSIBLE to me.
That's it, in a nutshell.
Chris.
Last edited by Screwdriverone; 29-08-2009 at 03:13 PM.
Not wanting to upset anyone but I think it is a meteor shot.
Basically for these reasons:
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.
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?
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!
4. I wonder if it was space junk or irregular in shape and perhaps tumbling.
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.
I'd love to see a bright meteor/space junk. So far I haven't seen a really bright one. It must have been a great sight.
It certainly has captured the groups notice and I am sure Chris is really glad he posted it!
An interesting thread, demonstrating (as Dennis has pointed out) the different 'cultural' approaches we take to reviewing images such as this.
Personally, I don't care one way or the other. If it is indeed a meteor, well....well done! If not...oh well.
I think it's unfortunate that Chris chose to react negatively to the process of evaluation and criticism. I think a few people were just trying to work through the possibilities of what may or may not have been captured. And keep in mind, Chris, that plenty of other posters wrote to congratulate you.
You need to accept that in a forum such as this there are going to be some members who approach images with inquiring/questioning/sceptical minds. They're not accusing anyone of being a bulldust artist. It's just in their nature to seek confirmation when it comes to claims of the more unusual or rare. That's all.
At the end of the day, you were there. You captured the image.
The photo is geniune Chris,i can provide all specs if nessary,i also had people with me when i took photo,i took the photo ar QLD astrofest.
so it not a fake
no one ever said it was a fake.Just not what you assume
Quote:
Originally Posted by hotspur
I had to use all my skills as a ametur astronomer, to capture this shot
I used a 4 inch ED scope on EQ5 mount,with canon 450D
Its a nine second ex,and my very quick reflexes to press button,just at the right moment,
regards Chris
Quote:
Originally Posted by hotspur
......it a fluke shot
.............
I am dismayed of the negativity,that some people have shown.
Quote:
Originally Posted by hotspur
.............
it may be "accidental excellence",but it does look cool!
regards Chris
so,it was all your skills and your quick reflexes? Then later it turned into just a fluke and accidental excellence.Gotta raise the BS flag here
The only negativity I see here is from you ,sorry OP but I can read this one with my eyes closed.You got called on your shot and threw your rattle out of the pram.Now dry yer eyes and stop imagining the world is against you,it's simple deductive reasoning and analysis of the facts,nothing more ,nothing less
Thank you Greg Bradley for you comments,you have so wel put on screen what i couldnt,Yes,i am a public speaker,i could of articulated that if i was having a beer with Stuart,But words on screen is very new to me.
Anyhow,i would like those who have been following ths to take a hard look at point Number #3.
This is the point that i have the most difficulty in accepting Stuarts thoughts,
the strongest point i believe in proving that it is a meteor are those "white spots", Stuart feels that they are hot pixels,he has done some study on them,and he feels that he is confindate,that with all his knowledge a skills,that,that is what they are.
The camera as i stated was in ICNR reduction,which OK isnt going to get rid of all noise,but hey,remember the camera was only exp for 9 seconds,Those 'white spots" are a hec of a lot of noise,also the camera
is only 3 weeks old(i can produce receipts),
Octane,it you had just paid $850 for a DSLR and it produced that much noise after 3 weeks,what would you do?My old 300D never produced tat much noise,and it was 5 years old.
I have donr some testing of the camera (450D canon) i did many exp
at nine second without INCR on,and no noise,i did tests with ICNR on
once again no noise.
As i stated i had other people with me that night(thanks Mike for the use
of your gear to test my new camera,and oh what a test its turned out to be!).
Appart from Mike i had another fellow who is a very good fried,and a prize winner of the coverted Astro fest photographic competition,not once but twice,
So there was quite a bit of high talent that was photographing with me that night,both these fellows were keen to see this new piece of kit.
I feel that to say "that the pic is of slewing star etc",is wrong because
i was working with Mike.and he recalls that we didnt take an exp wilst slewing,To both of us this would be incongreous,Mike used to belong to a distinct army regiment and to fire at a target when unsure would not have been an option,I to have had training of presscion instruments and to fire at a dingo,and not be sure of a kill is certainly not even worth thinking about(the current currency fo a dingo scalp in this shire is $100)
So,yes to say,we were firing at a star and slewing,is a bit,well doesnt sit well.
Another highly experienced astronomer/photographer has taken the image and done an evaluation,on those "white dots" and in his opinion
feels that the data,indicates that they are more star like than pixels.
I was'nt going make another comment,but Greg Bradleys' comments
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.
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?
Quote:
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?
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.
Quote:
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!
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.
Quote:
4. I wonder if it was space junk or irregular in shape and perhaps tumbling.
Perhaps, but that isn't a meteor, and why the bright spot in the middle?
Quote:
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.
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.
I'm having a beer at home, if you're having one as well, that'll have to do for a minute.
wrt
Quote:
the strongest point i believe in proving that it is a meteor are those "white spots", Stuart feels that they are hot pixels,he has done some study on them,and he feels that he is confindate,that with all his knowledge a skills,that,that is what they are.
The camera as i stated was in ICNR reduction,which OK isnt going to get rid of all noise,but hey,remember the camera was only exp for 9 seconds,Those 'white spots" are a hec of a lot of noise,also the camera
is only 3 weeks old(i can produce receipts),
I agree, that the ICNR should have taken care of these. I have no explanation as to why it didn't. Unfortunately the EXIF data on the photo says the exposure was >1024 seconds, which probably means you had it set to Bulb, as that's about 17 minutes. It's a shame the camera didn't record the time of the exposure.
Did you have any focal reducers or anything else in line? If I can work out how to do it, I'll chuck it through TheSky and try to plate solve the photo, I think I can work out the image scale (450D and 100ED right?). The last few times I tried something like that it was an effort in frustration, so it may take a while. That's why I want the previous shot, so I can look at the stars in the field you were shooting, much easier to use the MkI eyeball.
Unfortunately the EXIF data on the photo says the exposure was >1024 seconds, which probably means you had it set to Bulb, as that's about 17 minutes. It's a shame the camera didn't record the time of the exposure.
Did you have any focal reducers or anything else in line? If I can work out how to do it, I'll chuck it through TheSky and try to plate solve the photo, I think I can work out the image scale (450D and 100ED right?).
Hi Stuart
The EXIF data from a copy that Chris e-mailed to me shows 9 secs at 1600 ASA.
Here is a screen print from The Sky giving a FOV of approx 83’ x 55’ centred on NGC253 (not my image!)
[QUOTE=rat156;485492]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?
All mounts start off slowly and build up speed.
I am referring to what I have seen with my setup when the camera was say doing a focus exposure and I slewed it to some other spot. It leaves a straight line trail oir perhaps slightly curved. I'd have to do it again on purpose to tell but it wouldn't look like that it looks more like star trails and the whole line is the same intensity rather than a ball at one end and then trails off in brightness. All the stars in the image are lines or slightly curved lines.
9 secs is plenty long enough for that to occur but it would look different to that from what I have seen on my rig.
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.
Yes it can be a bit curved rather than dead straight but even.
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.
That's an assumption of what a star should look like. I have seen lots of stars that look like that in a very short exposure. At only 9 seconds they would be only barely exposed. My DSLRs never showed hot pixels that bright, that large and that many and certainly not with ICNR where there would be none. They are stars for sure. If his camera has that many hot pixels its time to take it back to the shop for a new one! Not saying for sure they aren't hot pixels but hot pixels on my cameras are way smaller and far less. In the CCD world a camera with that many "hot pixels" would be engineering grade or lower. DSLRs are different but the Niukon D70, Canon 20Ds and 40D I have used never showed anything like that many and that intense.
Perhaps, but that isn't a meteor, and why the bright spot in the middle?
Who knows what light comes off a buring meteorite or space junk can't answer that. I have never captured one just like that. Normally it is just an annoying streak of light in an image that disappears with median combine with other exposures that don't have it.
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.
Never seen any metoerites? Do you image from an urban location which suppresses them. At my dark site which has virtually no light pollution on a no moon night if I stood and watched the sky I would be pretty guranteed to see 5 meteors per hour minimum of varying brightnesses. I see heaps of 10 minute exposures with meteorites. I mean really common. yes satellites as well but they are only closer to dawn and shortly after sunset when they are still in the sun at their high altitude not in the dead of the night. The occasional jet lights too.
Meteorites are very interesting to watch. Some are really unbelievably fast and scoot across a large amount of sky, some are really slow depending on whether they are moving, which direction into or away from earth (ie earth catches up with a slow moving one going away from us too slowly or one that is coming at us at a great speed.
I have seen some leave smoke trails (not often) a few that were quite bright, one that came down almost like a firecracker but none that were big fireballs (I have just missed out a couple of times).
But in short they are a really common thing out in a really dark sky but they lack contrast and only the really bright ones are visible in urban locations. Perhaps that is what has setoff this discussion your experience of hardly ever seeing any where you image and others who see them a lot in really dark skies as a fairly common event (several a night when you aren't even really looking out for them). I don't see many meteorites at home either. Only the very few that are really bright and most I see aren't that bright but are visible.
I remember once looking out the window of a jumbo jet at 36,000 feet near the equator and seeing many many meteorites. Must have been a shower at the time.
The best meteorite I have seen was after a night of imaging I was struck by the beautiful sight of a small crescent moon with Venus nearby as dawn was beginning and I was admiring the beautiful view and thought gee it'd be nice if a meteorite flashed nearby and one did right nearby and it set it off just perfectly.
It looks like the ample proportioned female might be singing. Although there was a lot of heat in this thread I think in the end the process produced the best possible outcome. I certainly learnt from the different points of view. It seems everbody's feelings aren't too hurt after all but there is a rather strange bit of life advice from a new member in this thread.
Keep up the good work everbody. Cheers and a virtual beer for Chris and Stuart and everybody else.
*tongue firmly in cheek*
