156 replies to this topic

[tkottary]

I received my scope yesterday and i am quite disappointed with the focuser and rotator .Focuser is not very smooth. No marking on the rotator, rotator knob really needs to be tightened so much to avoid camera rotation .I could even rock the camera with knob fully tighten.

[RossW]

I received my scope yesterday and i am quite disappointed with the focuser and rotator .Focuser is not very smooth. No marking on the rotator, rotator knob really needs to be tightened so much to avoid camera rotation .I could even rock the camera with knob fully tighten.

Well that is disappointing. The focuser in my copy is truly buttery-smooth, so if yours is not, I would send it back for a replacement.

 

No marking on the rotator,

 

The images I provided in this thread show that there are no degree markings on the rotator; I agree that those would be helpful though.

 

rotator knob really needs to be tightened so much to avoid camera rotation .I could even rock the camera with knob fully tighten.

 

I see none of this with my scope, and the imaging train is reasonably heavy with the full-frame ASI6200, large 2" seven-position filter wheel, and large M68 OAG. I'd get a replacement.

 

Cheers,

 

Ross

[astro rocketeer]

I don’t have any of the rotating issues on mine either and I have a heavy Canon 60D with battery grip + ASI Air Pro on an L-bracket with all the cables hanging off of it. Sounds like you got a bad one. I’d return it if possible. This is a great scope!

[tkottary]

Yea i have asked Agena to replace the focuser and rotator if possible. I do want to keep this scope  

[desper0]

I also noticed that the coarse focus is not incredibly smooth, but the fine focuser knob is. It does not bother me, I would be bothered if the fine focuser were not smooth as I plan to fit a Sesto Senso focuser. No issues with the rotator. After reading this, I fit my heavies diagonal/eyepiece combination and it is rock solid. Haven't had the chance to check the optics as I received it yesterday and last night was used to finally getting some Mars pictures with my C9.25 after days of clouds. I plan to check it again tonight.. Beautiful little scope though..

 

 

[tkottary]

Here is the set up with RST 135 asi 6200 and sesto senso 2.

[astro rocketeer]

Here is the set up with RST 135 asi 6200 and sesto senso 2.

21BF785B-19CB-4B03-A894-6EA3496FE641.jpeg

Thanks for sharing. Whats the attachment you have between the telescope focuser and the cone that connects your filter wheel? Nice set-up!

[tkottary]

That is a Gerd Neumann CTU to remove any tilt . The dovetail bar that came with the setup is too small. When you add all the adapters the imaging train becomes very much back heavy . I need some raisers to mount it on bigger dovetail.

[desper0]

Here is the set up with RST 135 asi 6200 and sesto senso 2.

21BF785B-19CB-4B03-A894-6EA3496FE641.jpeg

Nice setup. Can you install the Sesto Senso 2 into the FRA400 with the bushings that came with the SS2, or did you need a custom one?

[tkottary]

Used the yellow bushing that came with SS2.

[Gene3]

I am hoping an FRA400 owner can help me out:

 

I am trying to have an adapter (M68 to M54) made for my FRA400 (on order, not received yet). I will be attaching a QHY268C image train which has the M54 thread and takes up 37mm of backfocus. I believe the BF of the scope is 148 but I am not sure how the 60mm of focuser travel impacts the BF and thus the length of the adapter I need.

 

I am struggling to get the BF information correct. Is it actually 148mm as stated by Agena Astro? The link to the Askar drawing shows it to be 110mm. http://www.askarlens...class2/182.html

If I go with the 148 then minus my image train (37) I get 111mm of BF. Then if I subtract the mid point of focus travel (30mm) from the 111mm I get 81mm for my adapter length. Does that sound right?

 

Also, Precise Parts who is making my adapter would like a very clear picture of the M68 thread at the back of the OTA that the adapter would be attached to, I am hoping a current FRA owner can take a couple photo's of the M68 thread and send it to me so I could pass it on the Precise Parts.

 

Thank you,

Gene

[nicknacknock]

Can’t help with backfocus, but here’s a M68 to M54 adapter if of interest..

[robonrome]

I am hoping an FRA400 owner can help me out:

I am trying to have an adapter (M68 to M54) made for my FRA400 (on order, not received yet). I will be attaching a QHY268C image train which has the M54 thread and takes up 37mm of backfocus. I believe the BF of the scope is 148 but I am not sure how the 60mm of focuser travel impacts the BF and thus the length of the adapter I need.

I am struggling to get the BF information correct. Is it actually 148mm as stated by Agena Astro? The link to the Askar drawing shows it to be 110mm. http://www.askarlens...class2/182.html
If I go with the 148 then minus my image train (37) I get 111mm of BF. Then if I subtract the mid point of focus travel (30mm) from the 111mm I get 81mm for my adapter length. Does that sound right?

Also, Precise Parts who is making my adapter would like a very clear picture of the M68 thread at the back of the OTA that the adapter would be attached to, I am hoping a current FRA owner can take a couple photo's of the M68 thread and send it to me so I could pass it on the Precise Parts.

Thank you,
Gene

Its not a backfocus requirement. The 148mm is the available amount of backfocus you have to play with. This scope is designed such that it doesn't matter precisely how far back your sensor is so long as it is within the available backfocus range. That is its party piece.

Edited by robonrome, 24 October 2020 - 08:27 AM.

[Gene3]

Its not a backfocus requirement. The 148mm is the available amount of backfocus you have to play with. This scope is designed such that it doesn't matter precisely how far back your sensor is so long as it is within the available backfocus range. That is its party piece.

Ok Got it. I forgot that the flattener is in front of the focuser.

[Gene3]

On the FRA400, is the male M68 thread M68x1 or M68 x0.75?

 

Thanks,

Gene

[RogeZ]

Gene:

New FRA400 come with M68-M54 adapters already. The older ones like mine are M68-M48.

[Gene3]

Gene:

New FRA400 come with M68-M54 adapters already. The older ones like mine are M68-M48.

Wow -seriously it comes with the adapter?

That is fantastic news and a huge relief.

Thanks,

Gene

[pmuller]

Its not a backfocus requirement. The 148mm is the available amount of backfocus you have to play with. This scope is designed such that it doesn't matter precisely how far back your sensor is so long as it is within the available backfocus range. That is its party piece.

I believe that the backfocus has to be spot on only with the reducer. Roger can probably say better as I got his reducer but weather has not helped me to test it yet 

 

I have had the scope for almost a month, have had the chance to literally use it for about 8 hours (3 different nights) as South Florida weather has been brutal with the record breaking hurricane season. APS-C sensor delivers pinpoint stars in the whole frame.

 

Attached a 5 mins sub from a B3 site, no calibration, just stretched 

Attached Thumbnails

• 

Edited by pmuller, 24 October 2020 - 05:29 PM.

[Cziffra]

Would the Askar reducer work with other refractors of similar f ratio?

[robonrome]

Ok Got it. I forgot that the flattener is in front of the focuser.

One point to note is that the above applies to use without the optional 0.7x reducer. If you use that then you need to set up a specific 55mm backfocus distance from reducer to sensor.

[aeneas]

I was just about to make a purchase of the Sharpstar 76EDPH F4,5 to complement my C11 SCT and then I saw this great review & thread about the ASKAR FRA 400.

 

How would you compare these two scopes if thinking primarily for astrophotography (using C11 SCT for viewing) and couples with the ZWO ecosystem (ASIair Pro, ASI2600MC camera etc.)?

[Gene3]

I was just about to make a purchase of the Sharpstar 76EDPH F4,5 to complement my C11 SCT and then I saw this great review & thread about the ASKAR FRA 400.

 

How would you compare these two scopes if thinking primarily for astrophotography (using C11 SCT for viewing) and couples with the ZWO ecosystem (ASIair Pro, ASI2600MC camera etc.)?

I did not realize that there was this 76EDPH available.

76EDPH is a triplet so you have to get the reducer/flattener which limits you to 334mm FL. The FRA400 is petsval design (no flattener needed) and gives you 400mm FL, with the option to add a .7x reducer to go to 280mm FL.

I am not impressed with the the tube ring setup on the 76EDPH, FRA400 tube ring set up looks better to me.

[astro rocketeer]

I was just about to make a purchase of the Sharpstar 76EDPH F4,5 to complement my C11 SCT and then I saw this great review & thread about the ASKAR FRA 400.

 

How would you compare these two scopes if thinking primarily for astrophotography (using C11 SCT for viewing) and couples with the ZWO ecosystem (ASIair Pro, ASI2600MC camera etc.)?

I have both the C11 EdgeHD and also the FRA400. I like how these two compliments each other one for a widefield and other for high magnification. I don't know much about the 76EDPH other than the obvious specs on various websites, but I have no regrets getting the FRA400 and I plan to keep this for a very long time. Petzval is described by some commercial as a luxury class telescope and especially being a Quintuplet, FRA400 truly shows luxurious quality (in my opinion) with a CCD and CMOS camera. I really like that its sharp stars all around, no flattener needed. Easy to mount to my SW mount, and compact/portable as well. I also saw someone posted on the classified a pretty good deal on one that only has been used a few times in the CN classifieds. Hope this helps.

[ippiu]

i look forward to seeing and maybe having Fra600 f5,6....On paper, it will be a real good petzval flat fpl53 apo...

[RogeZ]

These scopes are not specced to be FPL53.

As far as my FRA400, I think it is an amazing scope for the money, the optics are basically perfect up to APS-C with an Ha filter. Performance suffers a bit in color but not too bad.