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View Full Version here: : iStar Anastigmatic Objectives are back - bigger


glend
17-03-2017, 07:52 PM
Having built an iStar Anastigmatic scope ( a 127mm f12 R30 TCR in photo below) I know how wonderful these long focal length objectives in R30 glass can be. iStar are now back in the business of producing these objectives, after having stopped for some time as founder Ales Krivanek had been ill. It's good to see a return of these objectives:

http://www.istar-optical.com/objective-lenses-ii.html

The 250 mm (9.8") F/20 R30 looks magnificent, and you'll never have to think about CA with a focal length of 5000mm! Wish I could afford it, and had the room in the observatory.

anj026
17-03-2017, 08:15 PM
I also made a nice scope using the 127 f12 R30 lens. It is a good lens and I think these R30 spec lenses are especially suited to large observatory refractors due to the extra weight of the special glass.

With D&G being harder to get and more expensive it is great to see iStar still in business.

Saturnine
17-03-2017, 09:43 PM
Would love to have either the Istar 180mm or 150mm f8 R30 but the budget is exhausted but have settled for an Surplus Shed 150mm f8 at less than half the price and should be delivered later this month. If it performs as well as their 127mm f9.4 I'll be happy.

anj026
18-03-2017, 09:10 AM
The APM 152mm f7.9 ED lens in cell another option but it would be over $2600 AUD to get one. TS in Germany sell the Skywatcher 6" f8 achromat lens in cell. It looks like it would be around $650 -$700 AUD.

Saturnine
19-03-2017, 10:09 AM
Have been aware of the APM 150 f7.9 & the 140 f7 EDs', desirable but on a now pensioner budget is a bit too much of a stretch. wish I had seem them a few years ago before retiring. The S.S. 150 f8 I jumped on with there pre - order special offer of $325 USD, so about $500 AUD to the door, too hard to resist. Another project now !
Shoulda', coulda' got an iStar 150 f10 lens a few years ago when they were a little cheaper and our $ was closer to parity but f10 would've been testing the limit for my mounts so was always a bit reluctant.

anj026
19-03-2017, 05:43 PM
When you build your scope Jeff, please start a thread and tell us all about it.

I still have a couple of iStar 127mm f5.5 lenses sitting in a box. One day I will have another go at a binocular or else just make a wide field low power scope.

Saturnine
19-03-2017, 10:21 PM
I hope we're not hi-jacking the original thread about iStar anastigmatic lens which from all reports sound very good value.
Was just reading the thread on Cloudy Nights about the APM / Lunt 152mm ED scope / lens and that does have me dreaming, but then again the weather around here lately means that no scopes are being used anyway regardless of their quality.
When the SS 152 f7.9 arrives and the build begins I will try and document the steps and the first light report as well.