What is a high end 110-115 refractor?

[gregbradley]

I am starting to get the itch to use another high end 4inch plus refractor.

I have had a couple of FSQ106 (106N and 106EDX 111) and they are lovely instruments for imaging. For visual not so much.

I had a TEC 110 F5.6 fluorite triplet which was fabulous. The focuser though was a bit on the weak side but could be made to handle a FLI Proline 16803 which is about as heavy as CCD cameras get.

107-115mm would be good, a triplet, a good focuser that can hold a decent load and illuminate a 16803 sensor corner to corner with a decent flattener.

Availability of a reducer would be nice too.

Am I dreaming thing a 4 inch scope could be good as a visual instrument?

I had a Tak FS102 scope as one of my early high end refractors. It was way too dim to be interesting as a visual scope. 140-150mm seems good for that but now its heavy and expensive.

At some point an AP130mm GTO with the quad compressor would be ideal as it would probably match or beat an FSQ130 which I would love to have but at $20K its not happening.

There are some Chinese scopes that are high quality these days. Stellarvue is a contender. Sharp star, Rover, CFF (expensive) are contenders.

What would you suggest?

Perhaps all roads lead to another FSQ106ED! Except I want also a scope for visual.

APM have a 140mm APO doublet for US$2990 which is amazing value.

Greg.

[Atmos (Colin)]

I’d throw a TSA-120 into the mix and a contender.

[gregbradley]

Originally Posted by Atmos

I’d throw a TSA-120 into the mix and a contender.

Yes. Reading about TSA102 sounded great and I well remember Paul's fabulous series of TSA102 images. A 120 could only be better.


Odd size though 120mm. I wonder why they didn't go 130? I suppose they have the TOA130 for that.

Greg.

[Slawomir (Suavi)]

Hi Greg,

APM should have some nice telescopes with LZOS lenses.

I have been thinking of pulling a trigger on CFF 135mm with 3.5FTF (limited run of 4 only) which is nicely priced, relatively speaking, and has a 55mm imaging circle. But it is bigger than 4" you are after.

[glend (Glen)]

Hmm, Doublets, they just can't compete as imaging platforms, although the new TS125 with a FPL-53 & a Lanthanum glass element (not just coated, it is actually the glass) , look pretty good.. The Stellavues, Sharp Star, are the pretty much the same as the TS Triplet Apos and currently TS is more cost effective as a direct import. Stick with your size limit, once you start throwing in 130mm triplet scopes they get heavy.

Consider your motivations, if your looking for a scope in that size range you have many choices that can do the job but is it important for you to be able to brag about LZOS, or Tak, etc . I'm a cheapskate, I want the best possible specs for imaging for the least amount of money, and that eliminates all the high end "name premium" scopes.

[gregbradley]

Hi Glen,

I was just looking at Sharpstar and TS and yes they are the same. But Sharpstar prices are much the same as TS once you pay shipping and GST.


I agree about keeping the size under control. I have other larger scopes so this would be more about portability ease of mounting and use.

107 6.5 looks good as an allrounder.

Greg.

[Retrograde (Pete)]

Throw the Skywatcher Espirit 120 into the mix?

[casstony]

The Esprits are very nice but heavy for their size.

[Profiler (Profiler)]

Skywatcher have a new 150 APO Doublet refractor which is due for release any day now. It is currently advertised on various Oz astro stores as being approximately AUD$2,800. It is F8 and has a FPL51 lens.

[el_draco (Rom)]

Whats a "high end" refractor...
Any thing that makes you whistle loudly whilst thinking "holy momma"
... applies to other things as well

[LewisM]

A couple come to mind:

AP's reintroduced Traveller

TEC 110, but I think you had one and didn't like it?

TSA 102 or 120 (simply perfect)

Not sure I'd recommend Sharpstar...seen more than too many horror stories, and NOT worth the extra for SV or TS to check them for good ones

Any of the old TMB or Made for TMB (W.O) series

Anything with a LOMO or LZOS objective up front (APM, older SV)

[roughy (Mark)]

There is an FSQ106 EDXIII on the second page of the IceinSpace classifieds at the moment for 4.5K including accessories. Originally posted 6/2/18. Seller states pick up only in the Sydney area.

[Slawomir (Suavi)]

I believe there is only one 4" refractor that can well handle KAF-16803...FSQ 106.

[glend (Glen)]

The Agema 120mm looks to have the best specs of comparable Doublets of this size range, and a pretty amazing Strehl ratio comparison at all wavelengths.

http://www.agemaoptics.com/telescopes/

[Slawomir (Suavi)]

Agema 120 is surely a fine visual and photographic instrument, but f/8.7 and 42mm imaging circle might not be the best match for Greg’s KAF 16803.

[LewisM]

Originally Posted by roughy

There is an FSQ106 EDXIII on the second page of the IceinSpace classifieds at the moment for 4.5K including accessories. Originally posted 6/2/18. Seller states pick up only in the Sydney area.

I believe it is sold actually

[roughy (Mark)]

Originally Posted by LewisM

I believe it is sold actually

Not surprised at that price.

[gregbradley]

Thanks for the replies so far.

The Agema scopes sound nice, like the Tak FS scopes but probably better correction.

The TEC110 I had I loved but sold it to fund an AP scope which I love more!
Yuri does not make those TEC110's anymore and tried to do them at F6.5 or so instead of F5.6. No way.
The focuser is light weight really and suits a lighter to medium imaging train.
In hindsight I think it would have been good to remove the focuser completely and replace it with a Feathertouch or even a fixed adapter tube and attach an Atlas electronic focuser. The original focuser could be reattached if you wanted to use it visually.

The FSQ106EDX is definitely an interesting and well proven scope. The scope doesn't have to be able to handle a 16803 camera as I could also use the Microline 16 which is the KAF16200 APSh sized sensor.

Greg.

[Peter Ward]

Soo...can I interest you in an AP130 with FFC and FFR? ....just kidding

[troypiggo (Troy)]

Seen the AP 130 Starfire in classifieds?