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JaseD
02-07-2017, 12:13 PM
Hi all,
It was Territory day last night, and I was out with the camera (scope was left inside as it wasn't great seeing). At about 2300, I saw some cloud patterns that were interesting so I turned the camera skyward. I noticed an artefact in the first crappy image, (slightly off focus) and thought was is that? I pulled the camera out of the tripod and had a look. Replaced it and re-set the image, took it again, same artefact. Upon looking deeper, I think it is a comet, C/2015 V2 Johnson. It is in about the correct location in the sky, according to southern comets. This is my first ever comet, and it is also a chance shot, but certainly won't be my last attempt.

Bare in mind these are not planned and are quick and dirty. Shrunk to size with LR.

Thoughts??? Am I right?

Cheers
J

JaseD
02-07-2017, 12:15 PM
f5.6, 18mm, 20 seconds for both images.

leon
02-07-2017, 12:59 PM
Jase i am no expert by a long stretch of the imagine, but i reckon you have captured internal lens reflection. :shrug:
Hey, but who am i to question it, :question: some here more experienced will surly make comment. :thumbsup:

Leon :thumbsup:

blink138
02-07-2017, 01:09 PM
sorry jase i think that is internal reflection
pat

JaseD
02-07-2017, 01:26 PM
okay guys. thanks never, seen that before.

RB
02-07-2017, 09:00 PM
Definitely an internal reflection.
It's caused by the bright moon hitting the sensor and reflecting back up onto the inside of the lens, probably bouncing back off a lens filter like a UV filter if one was fitted and then returning back onto the sensor causing this anomaly.

Lens hoods help reduce this effect but removing any lens filters such as UV filters will minimise this best when there's any bright sources of light in the FOV.
Also, higher quality lenses have better multicoating to reduce internal reflections but they do still occur if the light source is strong enough.

RB

:)

JaseD
02-07-2017, 09:00 PM
I'm just curious as they hit the same point in the image. Even though I removed the camera from tripod, moved tripod head everything... once the clouds clear I will throw the scope up and try properly.

RB
02-07-2017, 09:02 PM
It's at the same point because the moon is at the 'same' point in the FOV.

JaseD
02-07-2017, 09:32 PM
Thanks for your response Andrew :thanx:. I had never seen them before. New to Astro, not to photog, even those these images wouldnt show it lol. As a result, I don't use UV filters and the like. Mainly ND grads reverse grads and polarisers... nothing on cam last night, that's why I wanted to know.

Anyway, will try again, always want to get better :lol:

Cheers J.

RB
03-07-2017, 07:34 AM
Don't give up Jase. :)
My first comet was a contrail at sunset.
But I stuck to my guns .... and .... eventually I shot that plane down. :lol:

Once you bag a real comet you'll never look back and it becomes very addictive after that.

Cheers
RB