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Istar best achromat for big refractor build ?

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35 replies to this topic

#26 Kunama

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Posted 10 September 2013 - 08:50 PM

I think the 8" F9 is about the biggest I would want to put on the mount, although no doubt it will carry much more weight, I still need to be able to move the thing around. At the moment I can carry the mount but the pier needs a trolley. I am guessing the all up weight will be about 150Kg or 330 lbs. When complete I hope to take the lot to starparties on a custom cradle in a trailer.

#27 RGM

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Posted 11 September 2013 - 07:11 AM

Bob, doubles and planetary viewing is what I want the scope for. Where did you buy yours?


Derek, I purchased mine from Canadian Telescopes. At the time they were having a sale. If you contact Mike at Istar, you might find they have a few overstocked scopes at a sale price. I believe they will cover a portion of the shipping from Florida.

#28 dan_h

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Posted 11 September 2013 - 08:08 AM

Bob, doubles and planetary viewing is what I want the scope for. Where did you buy yours?


Derek, I purchased mine from Canadian Telescopes. At the time they were having a sale. If you contact Mike at Istar, you might find they have a few overstocked scopes at a sale price. I believe they will cover a portion of the shipping from Florida.


Istar currently has an ad on AM for a sale of overstock items. There are a couple of nice sized scopes available at a decent discount.

dan

#29 dlapoint

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Posted 11 September 2013 - 11:44 AM

thanks guys, I will look into it

#30 rwiederrich

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Posted 11 September 2013 - 03:43 PM

Just a generic question, but why not an 8" F16 for super planetary type work? is the mounting issues of such a long tube the main problem? FL would be like 3200, so not too much in terms of magnification... Just wondering why nobody builds longer FL than F12 generally?

Al


I wouldn't say that...I had a hand in builing a 6"f/15 and I build my 10"f/15.

Rob

#31 Jon Isaacs

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Posted 11 September 2013 - 03:57 PM

I wouldn't say that...I had a hand in builing a 6"f/15 and I build my 10"f/15.

Rob



Rob:

Who made the lens for your 10 inch F/15? You didn't make that yourself did you?

Jon

#32 Jon Isaacs

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Posted 11 September 2013 - 04:00 PM

Interesting photo.

I am not seeing the blue-red/orange atmospheric refraction at the bottom and top of Venus that I see with my reflectors (and apo's).

Jon

#33 Messyone

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Posted 12 September 2013 - 03:39 AM

Interesting photo.

I am not seeing the blue-red/orange atmospheric refraction at the bottom and top of Venus that I see with my reflectors (and apo's).
Jon

Jon thats because the Istar objectives are that good...really. I have a great Synta 6" f8 but am in the process of building a 6" f12 Istar scope. f12 is a long as I could go with my mount and tripod.
Rob I think I should join your refractor group.
Matt

#34 mikey cee

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Posted 12 September 2013 - 09:37 AM

Matt Istars are more than good...they are great. But you will still see atmosheric dispersion or aberration. I do. Just wanted to set the record straight. ;) Mike

#35 Kunama

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Posted 12 September 2013 - 04:24 PM

Thank you all for the feedback, I have decided to go with the Istar objectives and once underway will do a thread in the ATM forum.

#36 beanerds

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Posted 13 September 2013 - 04:46 AM

;) what are you suggesting Jon ? , here is the original , sized for CN's of course .
Brian.

Interesting photo.

I am not seeing the blue-red/orange atmospheric refraction at the bottom and top of Venus that I see with my reflectors (and apo's).

Jon

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