Author Topic: 17P_Holmes  (Read 1172 times)

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JohnP

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17P_Holmes
« on: Dec 05, 2007, 23:50:15 »
Popped out last night in between the clouds - It was very windy so decided to try widefield of 17P Holmes. Used EOS on ZS66 with 0.8X Flattener - acquired 10 x 45secs unguided at ISO800 - It was a very quick & rough image..

Anyway this thing is massive - pretty feint now - I could just see it with 10x50 bino's - I struggled a little to find it through the EOS/ZS66.. I guesstimate that it's approx 60 arcmins or 1 deg in diameter i.e. twice the full moon.

The attached images are a sampled down version (800 X 600 pixels) & a crop from the full size frame to show you how massive it looks on the EOS.

I can't wait to look at this with the 12 inch dob at Tuesnoad...

Anyway hope you like,

John.




MarkS

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Re: 17P_Holmes
« Reply #1 on: Dec 06, 2007, 06:35:56 »

Nice image John!   It certainly is huge now.  Looking at the background stars in the star chart I agree with your estimate of 60 arcmins.  Far too big for my C11   :(

Mike

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Re: 17P_Holmes
« Reply #2 on: Dec 06, 2007, 09:49:24 »
Very nice John. 60 arc mins - Thats huge !! I was hoping to get an image of it this weekend (weather permitting). If it is that big it will have to be a job for either the ZS66 or my Nikon D70.
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

JohnP

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Re: 17P_Holmes
« Reply #3 on: Dec 06, 2007, 10:51:30 »
Hi Mike - yep definitely Nikon & ZS66... It filled an appreciable part of my EOS frame & I was using the ZS66 with a 0.8X Field Flattener... Good thing about that though is that it was reasonably easy to image as I didn't need to bother with guiding etc. & accurate Polar alignment.

Hi Mark - thanks for your comments - took me a while to find it because it was so big & diffuse...! I wasn't using a finder scope so had to basically point my scope in general direction & take short 5 to 10 sec subs till I could see it...

I would say given the chance down at Tuesnoad this will look great - also nice low power eyepiece on the 12-inch....

John

Tony G

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Re: 17P_Holmes
« Reply #4 on: Dec 06, 2007, 11:22:43 »
Another good image John, and hopefully you can remind me (again) how to do something similar at DSC.

Mike this image is on spaceweather.com today and is a 90 sec exposure with a Nikon D70 and nothing else.




Tony G
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Mike

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Re: 17P_Holmes
« Reply #5 on: Dec 06, 2007, 13:23:56 »
NIce! I'd be pleased with that. Let's hope we get a gap in the clouds over the weekend.
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Rick

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Re: 17P_Holmes
« Reply #6 on: Dec 06, 2007, 13:44:29 »
It sure is a weird comet. Last time I remember seeing one that covered an almost circular patch of sky that large was IRAS-Araki-Alcock back in 1983, and it was that large because it was close...