Looking for a small (60-110 mm) refractor to piggyback on a C11" for Imaging

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Bruce Donzanti avatar
I currently have a Stellarvue 80mm apo triplet (old version) piggybacked on a C11" EdgeHD to image from my observatory.  I am not pleased with its performance, so I am looking for a new scope to replace it and pair it with my ASI2600mm.  Weight is not an issue and forget cost for now.   It will be high up in my observatory, so I need to make sure there is a good auto-focuser option to install.   I'd appreciate any suggestions from those who are using good, at least, triplet apo refractor in the FL range. 

Bruce
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wsg avatar
Bruce.  I am impressed with the Askar FMA lineup.  I own the 180mm FL and 260mm, they make models all the way up to 600mm I believe.  They are ready to go right out of the box with reducer/ FF's and even mounting hardware. 

Cheer's
scott
Bruce Donzanti avatar
Thanks, Scott.  I will check them out.  Your images with them look great.
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Lynn K avatar
If $$$ and  weight is not an issue.  Then The Takahashi FSQ85ED.  May have issues if using a full frame, but you shouldn't have any issues with the ASI2600.  The FSQ106 is very heavy.

Lynn K.
Chris White- Overcast Observatory avatar
I'd look at a Stowaway.   It's a wonderful scope, and both the reducer and flattener work perfectly with APS-C.
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Seth avatar
Second the fsq85.
Bruce Donzanti avatar
I'd look at a Stowaway.   It's a wonderful scope, and both the reducer and flattener work perfectly with APS-C.

Yes- indeed.  I've been eyeing that, and the new 110mm  StarFire which has yet to become available in its first production run.  Both would work great with my AP1100 mount.  The 92mm Stowaway is also unavailable at this time unless I can find a used one.  

BTW- nice write-up on the NINA HF Aberration Inspector.  I've been using it since it became available.  Wonderful tool that George developed.
Chris White- Overcast Observatory avatar
The new 110 should be interesting. Not much info about timing. Roland said they are actively in the production phase but they also said they were finalizing material specs on the reducer. The real draw for that is that it's designed to handle imx455. 

I dont know if it will be a 2022 or 2023 thing. Who knows. 

The stowaway is tough to beat though if you plan to use aps-c. I never tested it with imx455 but the reducer definitely wouldn't support it. Maybe the flattener would?? It would be really close.   They are easily had on the used market and there is virtually no copy variation so you're almost guaranteed to get a good one. Plus AP happily supports second owners. 

Personally, I don't like the color correction of any of the fsq scopes. They are optically old designs and don't play well with the tiny pixels. Tak redesigned the flattener for the toa line and they are incredible. It would be nice to see an update on the fsq as well.
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Michael von Berner-Purgstall avatar
SW ESPRIT 100ED - good examples do have strehl of 0.95 - 0,98 and it is a perfect mix of $ and performance and with the APS-C sized sensor of the 2600 you can even use a Riccardi-Reducer to get 412mm at f4.1 instead of the native 550mm and f5.5.

:-)
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Lynn K avatar
I had the opertunity to get on the AP Stowaway list.  I have the original Tak FSQ106ED and though there may be an AP advantage of superior optics, I couldn't justify the difference. I use Starlight Xpress Sx814 & SX46 plus QHY268 on the Tak at F3.64.  I have beed very happy with it. Going to full frame will bring on a whole new level of flat field issues, not to mention filter cost. That,  I can/t justify for the extra realestate.  I also don't invision myself traveling to NM or Hawaii with the scope.

I refuse to pay $1000-$1500 profit to a Stowaway reseller.

I have been notified my AP about the AP110 list, when it comes up.  I have a AP130GTX and even though the QUAD reducer/corrector does not give a flat field with a full frame, I have difficulty selling the AP130GTX and replacing it with the AP110, just to get more celestial realestate.

Just my openion, but I would have difficulty putting a 5K plus scope on a mass produced spherical SCT as a scondary imaging scope.
By the way I have a Celestron C11XLT, 9.25XLT and Edge 8.  All greate scopes vuisually, and not bad photographically for the buck.  I did mono filtered Hyperstar with the C11 for years.  A lot of work!, and the FSQ106 will match it with a lot last hassle .  A bit off the subject, but I am in the process of setting up a  used Officina Stellare RH200 at F3 as my fast system and will be compairing it to the FSQ106 at F3.64. Not sure what to expect.

Lynn K.
Bruce Donzanti avatar
For better or worse, right or wrong, I decided to go with the Tak FSQ85EDX.  No issue whatsoever with placing these small refractors on the C11" EdgeHD as the AP 1100 mount handles both scopes with ease to get fantastic guiding for very nice images.

Thanks all for the feedback and suggestions.

Bruce