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Long, yellow and very fast

Started by MarkS, Jan 23, 2010, 11:48:23

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MarkS

Quote from: JohnP
How much of the french stuff were you drinking last night then..... :-)

Funny you shopuld say that - I did have a glass or two of wine!  I meant EQ6 mount of course - now corrected in earlier post.

Daniel

I think you've probably made the right decision, have you checked how narrowband filters perform at F2.8? if you don't get the bandshift problems I get with the hyperstar then you realy have an incredible all round scope!

Just can't wait for a first light!!


Daniel
:O)

MarkS


It depends on the exact filter but the bandshift problems generally start when using optics faster than F3.  So F2.8 should be just about OK.

BTW I just saw this info about halos on the astronomik site:
[New thread] http://forum.orpington-astronomy.org.uk/index.php?topic=5725

RobertM

The Baaders I bought are certified down to at least f/2.8 and I've been using them at that without issue.

Mac

QuoteYes, I'm now the proud owner of a Takahashi Epsilon 180ED.  Focal length of 500mm at a very fast F2.8

how about an autofocus version 500mm f2.8, But its green.

http://www.sigmaphoto.com/lenses/lenses_all_details.asp?id=3349&navigator=3 :o

MarkS


It's massive!!  Weighs 35lb.  Take a look:
http://images.google.co.uk/images?hl=en&um=1&q=sigma+APO+200-500mm+F2.8&sa=N&start=0&ndsp=20

If that lens gives pin sharp stars without being stopped down, then it's an astrophotographers dream.  Very useful "wide field" range of 200-500mm at a whopping F2.8 and then a "closer up" range of 400-1000mm at F5.6.

And no diffraction spikes ...

Mac - buy one for your Nikon and let us know how you get on.  But being green you risk losing it in the grass at DSC.

Mark

Mac

QuoteBut being green you risk losing it in the grass at DSC.

That's what i was thinking. :cheesy:

mickw

The kids could take rides on it  :o
Growing Old is mandatory - Growing Up is optional

Rocket Pooch

One of the QSI Users has one of them, here's a picture with the QSI I have

http://farm5.static.flickr.com/4033/4281477453_5977cb5365_o.jpg

MarkS


I'll have to get used to diffraction spikes!

Mark