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multiweb
13-01-2015, 06:02 PM
Just inquiring how long lovejoy tail may be the 17th of january. I'm thinking of using a 200mm lens on the widefield rig. Should I use a 150mm instead? How faint is the elongated bit. Will anything show up on a 2min sub? I'll be shooting mono with a QHY9. TIA.

ozjoe
13-01-2015, 07:47 PM
Hey Marc,
did you find a way to clear our Hoxton park sky ?
hope it clears up for you.
Joe

multiweb
14-01-2015, 08:33 AM
Nope. It's either blue in daylight or bright orange at night :)

gregbradley
14-01-2015, 08:41 AM
From images I have seen Marc a 200mm lens should be fine with a full frame chip. If you are using a smaller chip like a micro fourthirds KAF8300 you may need 150. 200mm on a full frame is too wide and the comet is about a bit over half the field. But the the tail may be getting longer.

Wodaski has a ccd calculator that has pictures that are resized to show what different setups will produce. That would be helpful here.

Greg.

multiweb
14-01-2015, 08:46 AM
Thanks Greg. I'll use a 150mm then. :thumbsup:

doppler
14-01-2015, 09:04 AM
Hi here is a 135mm (1100d crop sensor) pic if lovejoy taken on the 12th. 11 x 30 sec subs at iso 1600, lens stopped down to f5.6 to reduce aberations.

Rick

multiweb
14-01-2015, 09:07 AM
Thanks for that Rick. Good indication it might fit in 150mm. :thumbsup:

Rob_K
14-01-2015, 02:44 PM
Suppose it depends how deep you want to go Marc. There was a deep widefield taken a couple of days ago in Mongolia that showed the tail faintly out to just over 12-deg length. Look forward to seeing what you can get, good luck! :thumbsup:

Cheers -

multiweb
14-01-2015, 02:54 PM
Thanks Rob. Yeah I guess you can go as deep as you possibly can. It's going to be a compromise between how fast it's moving, how clear and dark the sky will be and how sensitive the camera used will be.

I reckon the FSQ at 530mm FL should give me some really nice close up details and the 150mm less structure but may be a more interesting field. I'll see on the night what works best.

In the end I want a nice stacked image and also a time lapse.