Avalon Linear at 42lb of payload?

[cotak]

After a frustrating few months with my cem60ec I am now considering changing for a more up market brand.

The Linear gets good reviews but it's payload capacity is a bit lighter than similar mounts with worm and wheel drives. It is significantly less costly than the closest competitor for me though and by spec I should be within the 44lb limits but I wonder has anyone ever put that much on one and had good results?

My use case will be with a 10" GSO truss newt for the moment. And it's long enough and heavy enough that I'd like to find out what owners of the Avalon thinks.

Edited November 1, 2019 by cotak

[Skipper Billy]

I ran mine with 36 lbs on it and it never flinched.

I was extremely happy with mine and only sold it as I needed a significant uplift in weight capacity. It was one of the easiest to use mounts I have ever had.

If you get one spend some time getting your guiding working well - short sharp corrections required and short exposures.

One other thing - the subs always look better than the guide graph suggests they should - I dont know why! Maybe the very slight elasticity in the drive belts?

I would have another one without a second thought.

 

[cotak]

Sounds good.

How did you find galaxy season with short exposures for guiding? I'll be using an OAG and hopefully that's not a big problem to run 1s exposures.

[sloz1664]

I use an OAG with both my Tal 200K and my Dual AA80 Triplet / WO Star 71 setups on my Avalon Linear with no issues. The Tal 200K has a 3.5" Baader diamond focuser attached, together with filterwheel, OAG & a Atik 460.

Steve

 

[AngryDonkey]

I only use short focal length refractors on my Avalon Linear but am happily running 40lbs payload without any issues.

[newbie alert]

After a frustrating few months with my cem60ec I am now considering changing for a more up market brand.

what issues are you having as I've only heard of good reports about the cem range?

Edited November 3, 2019 by newbie alert
Damn phone

[cotak]

On 03/11/2019 at 04:20, newbie alert said:

After a frustrating few months with my cem60ec I am now considering changing for a more up market brand.

what issues are you having as I've only heard of good reports about the cem range?

There's a 2" p-p SDE oscillation that PEMPro reports as 0.3X" RMS. So yes iOptron after many weeks of pestering by me agrees I can return it for repair. However, their guess at a bad bearing for root cause is likely just a random shot in the dark as there's a beta firmware which shows zero oscillations but which cannot be guided and which they seems to have stopped investigating as a possible solution (reason is limited resources, to which I say "go boil you heads). And I know someone's 120EC2 was not fixed after 4 months at their office and was returned with the same problem as I see in my 60EC. As they never answered if the PEMPro 0.3X" RMS will be taken by them at their office as in spec, I have not sent it back as why waste the money in rather expensive shipping from Toronto to Boston. 

Now, that said in typical seeing nights you wouldn't really noticed as while it's 1-2" p-p it is RMS down to less than that and you stars can be round providing the optics is fine. The experience of the support has left me burn enough that I don't want to continue being a customer for them. It took from July till now to get acceptance for a return for repair.  During the course of which repeatedly their responses was "Wait for the software fix" which thus far never came, and in the end I think never will.  My conclusion from all the exchange I have had with them is that the techs  you talk to don't really know enough to give you good answers, or are prevented from telling the full story. The real brains are in China and you can't get at them directly (likely due to the joint venture structure) so you end up playing a telephone game where you tell the Americans one thing and get answers days later from Nanjing but with all the risk of miscommunication included.  

The PE Spec for the EC are IMHO worth less than face value. Sure it is supposed to be <= 0.3" RMS but because it is RMS your real PE can be much larger and their techs claims a 1" p-p sine wave should result in 0.3 RMS, well it does in PEMPro except that Ray seems to indicated that isn't the full story as PEMPro might not be correctly sensitive to oscillation frequencies that are not integer multiple of the known fundamental. Trying to get a definitive answer from iOptron has been impossible for all those reasons above.

It is a bit of a sad situation because this story confirms all the worse of the American tendencies over on their forum about "premium" mounts. There's a lot of promise in the EC range but thus far it seems there are fundamental cost trade offs made that means they don't quite perform to the level where they truly represent unequaled value. For me that sucks cause having the ability to run 4 second or more guide exposure is great for galaxy seasons which is why I asked if anyone had issues with galaxy season and the recommended 1s guide rate from Avalon.

Edited November 5, 2019 by cotak