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Anyone using an Avalon M Uno?


schmeah

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Hey Pete, feel free to question my purchases and in fact anything that I do and that I think that is right - I've been doing this for only 4 years, I am far from an expert. :) and only by questioning what we do, do we improve.

I am just looking into the benefits of plate solving and automatic focus - I have a notice pinned on my obs wall that read ' If it works leave it alone' - I fear that this has hindered my progression and kept me firmly in the dark ages!

I guess what I am saying is that we all find our own ways of working and what fits in with our lives. I've developed my capture style in isolation out here in Spain having never seen anyone capture a single image in my life. My way is certainly not the right one!! :)

The M-Uno was certainly my first choice as it happens when I looked at changing my mount. We decided (the retailer and I) that perhaps with my scope and imaging train it was going to be a little long for comfort on the Uno and certainly not a gamble either of us wanted to take if it didn't work out. So I am stuck in Linear land, albeit fairly happily stuck!!

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I think the automated flip (and automated everything else) is fine so long as you have a permanent set up where you have made sure nothing is going to go wrong. Like a post above said, i would be worried about cable snags ect and may actually loose sleep rather than gaining it. I know automating a rig is possible to do even if you are setting up from scratch every night but i really dont trust myself to set up perfectly each night then hit the sack hoping nothing goes wrong.

Preforming a meridian flip is no hardship but getting out of bed is! I use a NEQ6 and the only reason i would upgrade to the M-Uno at the moment is so i could get a decent nights sleep. Every other bonus of the Avalon mount is just that, a bonus.

Going off topic a little, i'm going to have to looking into the rain alarm that Sara mentioned, that would let me sleep easier! Dont trust the weather ever since my rig got rained on a couple months back.

Callum

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As Olly mentioned, and he and Sara demonstrate, the final image is what determines whether or not our mounts are performing up to our expectations. If I don't have tight, round stars after long exposures, then it doesn't matter how much sleep I got. I imaged for years with a fork mounted LX200R and got satisfactory results, but lost many subs due to poor guiding, and spent hours in processing trying to get misshapen stars to look better. So when I decided to upgrade to the M UNo, the primary factor was expected superior tracking, with no meridian flip requirement being secondary.

I chose the M Uno over comparably priced GEMs such as the AP Mach 1 because of the fork simplicity and expected low maintenance and tinkering requirement of the belt driven system. But if it doesn't track comparably, then I've made a poor choice. So what makes a GEM inherently superior to a fork mount in regards to tracking? And how do we truly measure accuracy of tracking, when the image sub quality should be the final measure. Everyone quotes P-P unguided PE, guided RMS etc and post detailed PHD graphs. But periodic error is not applical with these non worm/gear belt mounts, and even though the absolute tracking errors may be larger, they are gradual, smooth and easily guided out. I've examined my initial PHD guide graphs and while "good" (RA RMS in the 0.5 arc-sec range), should they be better for a higher end mount? I'm sure I could get numbers better with some tinkering, but I suspect I would be wasting my time, particularly in my locale where the seeing is average at best. So if I can get tight round stars at long FL with long exposures, the extra sleep will just be a nice bonus.

Derek

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  • 4 months later...

Hi Derek,

i found your post  regarding the M uno just now. Im in a proccess with  the vendor in Italy to buy the M uno..

What I read in all the posts here helped  me to the final decition to buy the mount.

I will be happy to get any more tips here from the group.

My sytstem now is the  EQ6, EQ5 , and GSO 8" f8 RC  scope.  i have a lot of tracking problems from the  EQ6 (a used one).

last week  i took the old EQ5 to our south desert , and the results was better.

1. i will use the PHD, do you need to recalibrate  during the night, or the the first start of evening is good for all night?

2. is there a preffered  location  in sky to  make the  PHD calibration? (for un flliped mount)

3. Im only  1 year  in the field of astrophotograhy,  so please note that Im a novice...

 thanks

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Hi Derek,

i found your post  regarding the M uno just now. Im in a proccess with  the vendor in Italy to buy the M uno..

What I read in all the posts here helped  me to the final decition to buy the mount.

I will be happy to get any more tips here from the group.

My sytstem now is the  EQ6, EQ5 , and GSO 8" f8 RC  scope.  i have a lot of tracking problems from the  EQ6 (a used one).

last week  i took the old EQ5 to our south desert , and the results was better.

1. i will use the PHD, do you need to recalibrate  during the night, or the the first start of evening is good for all night?

2. is there a preffered  location  in sky to  make the  PHD calibration? (for un flliped mount)

3. Im only  1 year  in the field of astrophotograhy,  so please note that Im a novice...

 thanks

Hi 4X. Glad to see a new M Uno owner! I never need to recalibrate after starting a session. In fact, with the M Uno I get to sleep through my entire sessions :) To my recollection PHD suggests calibrating near the equator (dec 0), but I do fine calibrating on a star near my intended target. Good luck! If you haven't already, consider joining the Avalon Instruments Yahoo Users group.

Derek

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Hi Aaron. I am very happy with the M Uno, and now that I am imaging at longer FL (2350) and am still not wasting any subs due to poor guiding/tracking, I am convinced that I made the right choice. If you have any questions, feel free to ask me here, or PM me.

Derek

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I remain intrigued as to why the Avalon's results seem so much better than its guide trace. The guide trace I get isn't bad but I've had better. I haven't had better results, though. My guess, and it's only a guess, is that a guide trace records only the position of the corrections. What is happening between corrections is not shown. Perhaps the Avalon's secret is that after a correction the mount is restored to the right position very quickly indeed, so spending longer in the right place before drift sends it to the position of the next correction.

Anyone reading this thread might also want to look at this one in the reviews section; http://stargazerslounge.com/topic/243024-avalon-systems/#entry2638466

Good service and a good attitude are another major Avalon plus, it seems. 

Olly

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Hi Olly. Yes, it would appear that the corrections are so quick, the guide star snaps right back on pixel. There doesn't seem to be much if any difference in my results whether my total RMS is 0.4" or 1.2" (typically in the 0.5-0.6 range) at an image scale of 0.65" per pixel. My stars are never out of round (flatness typically less than 0.05 in Maxim) and FWHM typically in the 2.5" (seeing dependent) range regardless of the guide trace. So many focus on the guide trace and tracking/guiding numbers when buying quality mounts. But it doesn't seem to be strictly applicable to these mounts.

Regarding customer service. Truly stellar. When I was having issues with StarGo initially, it seemed that Luciano was down the street rather than across the Atlantic. My experience was similar to Phil's. Why was his thread locked, BTW?

Derek

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Hi Olly. Yes, it would appear that the corrections are so quick, the guide star snaps right back on pixel. There doesn't seem to be much if any difference in my results whether my total RMS is 0.4" or 1.2" (typically in the 0.5-0.6 range) at an image scale of 0.65" per pixel. My stars are never out of round (flatness typically less than 0.05 in Maxim) and FWHM typically in the 2.5" (seeing dependent) range regardless of the guide trace. So many focus on the guide trace and tracking/guiding numbers when buying quality mounts. But it doesn't seem to be strictly applicable to these mounts.

Regarding customer service. Truly stellar. When I was having issues with StarGo initially, it seemed that Luciano was down the street rather than across the Atlantic. My experience was similar to Phil's. Why was his thread locked, BTW?

Derek

Supplier reveiw threads are now locked from the off to avoid 'supplier bashing' which can make life legally difficult for the forum's owners, I believe.

Olly

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  • 2 months later...

Hi guys,

Sorry to resurrect an old thread but it looks like I might get the answers I need here. I'm in Rotterdam, the Netherlands, a.k.a. light pollution hell so I have to be mobile to escape to a somewhat darker location. The M-Uno looks mighty appealing, not having to lug counterweights along and not having to worry about meridian flips certainly sounds good. However, flex in the mount does not. Being close to the sea means there's always wind at my observing site and I wonder how the M-Uno will handle that. I'm using a Mak-Cass which is 60cm long including dewshield so there's not that much surface area for the wind the grab, but still... I'm still puzzled how the flex can not affect the subs, can anyone explain? And what's the cause of the flex anyway, is it due to lack of stifness of the arm, elasticity of the belts or something else entirely? Thanks for any help you can give.

Jarno

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Hi guys,

Sorry to resurrect an old thread but it looks like I might get the answers I need here. I'm in Rotterdam, the Netherlands, a.k.a. light pollution hell so I have to be mobile to escape to a somewhat darker location. The M-Uno looks mighty appealing, not having to lug counterweights along and not having to worry about meridian flips certainly sounds good. However, flex in the mount does not. Being close to the sea means there's always wind at my observing site and I wonder how the M-Uno will handle that. I'm using a Mak-Cass which is 60cm long including dewshield so there's not that much surface area for the wind the grab, but still... I'm still puzzled how the flex can not affect the subs, can anyone explain? And what's the cause of the flex anyway, is it due to lack of stifness of the arm, elasticity of the belts or something else entirely? Thanks for any help you can give.

Jarno

The yahoo avalon group is a good place for information.

Alan

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Here another (we are two, realy) happy user of Avalon's mounts, I had a Linear with a Tec140 upgraded with an M-Uno to forget the meridian flip.

After two years of proud working from 180mm of my Apo Telyt, passing by taka baby fsq, to a GSO RC 8" at 1600mm, a month ago, I put it in our (owned by Mauro Ghiri and me) new personal remote observatory powered by Avalon "Merlino"  and all things works fine,

we are using a RC8" reduced down to f/5.8 with Atik One (694 chip) working at 0.87 arcsec/pixel and guiding at the half (lodestar on oag).

For any question, I aggree, the yahoo user group is a great resource, and Avalon service is truely stellar indeed  :smiley:

for info and firsts images we had taken, have a look at www.avogadro-observatory.com  :laugh:

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Hi Jarno. There was a thread somewhere, perhaps on Cloudy Nights, where there was detailed discussion regarding the possibility of flex in the avalon mounts due to belt elasticity. I don't want to call it a myth, but I haven't found any users who have substantiated this claim. I can, however, say that the only night in one year of frequent imaging where I lost subs due to out of round stars was on a windy evening, steady 15MPH with stronger gusts. I rarely set up on windy nights though, and I suspect that few mounts would perform well under those conditions. However, if you truly are going to be imaging under frequently very windy conditions, perhaps you should be looking for a tank that you KNOW will hold up better in the wind, Mesu perhaps? Overall I absolutely love this mount. Hour long subs at FL 2350 f/10 are now routine with tight, round stars always.

Derek

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Hello Derek, thank you for replying. I saw the CN thread you're referring to but I can't draw too many conclusions from it. For starters, there's an error in Mortens formula to calculate the wind force, it should be 1/2 * ws² * r-air * scope area * Cd, and without knowing the true modulus of elasticity of the belt I can't make an accurate calculation anyway. Some people are saying they're having problems in windy conditions, others say they don't, so whom do I believe? The nearest dealer is a 5 hour drive away and there are no other astronomers with an M-uno nearby so examining the mount for myself isn't feasible.

I'm currently using a Losmandy G-11 which is pretty close to tank level but it doesn't score very high on portability. Having to carry all your equipment down two flights of stairs each session gets very annoying, very fast and a mount without counterweights would make a big difference.

Jarno

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Hi Jarno. Who are the people saying they are having problems in windy conditions? I think most mounts have problems in windy conditions. I think the only way to judge objectively would be to compare different type mounts performance under the same conditions, ie at a star party. Assuming that belt elasticity will equate to worse tracking/guiding under windy conditions is a stretch (no pun intended). I think if I imaged in such windy conditions, I would be looking for a personal observatory, or at least some other form of wind blocking solution, rather than hoping that I picked a wind resistant mount. But again, I've had no problems in moderate wind. And even when my PHD RMS measurements are somewhat higher, the stars still come out round and tight somehow. Perhaps the belt elasticity has some positive effects as well, more rapid corrections, as Olly had alluded to earlier in the thread.

Derek

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I can only comment on my Avalon Linear Fast Reverse and TEC140.

If you hold the scope and push on it in any direction it feels more elastic than any mount I've ever come across except, perhaps, the spring loaded early iOptron IEQ45s. There's no mythology here, it just does feel elastic, but don't hang up because I like this mount! I run an astronomy guest house and welcome lots of experienced imagers. When they check out this rig they look quizzical and say, 'Does that work?' Well, yes it does. In fact it works very well.

How can it work so well with this elasticity? I don't know! But it does. Some thoughts;

- When we look at a guide trace we must remember that the only real information it contains is the position of the dots when each guide impulse is given. The curvy line joining the dots is pure guesswork by the software. My Avalon gives better images from the same guide trace and average error than I've seen in my EQ6 and Tak EM200 mounts with the same guide setup. My only explanation for this (and I'm certain the images are better when the trace is comparable) is that the Avalon returns to the correct spot faster than a backlash mount and so spends longer in the right place between the dots than a normal mount.

- The TEC is a long scope with hefty triplet out front and huge, heavy flattener lens at the rear, plus full format CCD and big filterwheel. The long moment of this setup probably taxes the Avalon harder than a shorter setup and I'm on the payload limit as well. But I have no plans to change this mount because it works well.

- My observatories are sheltered from the wind fairly well. When you walk carefully past the Avalon it is hard to get past it without producing a small spike on the guide graph so I cannot see this as a mount for very exposed and windy conditions. But in exposed and windy conditions the seeing is usually diabolical anyway and going to bed comes to mind.

I like the Avalon because it is very well made, precisely engineered, has phenomenal after sales support, readily available spares and because I find that it knocks out good subs. What I'm telling you here is pretty much what Ian King said to me before I ordered this mount. He asked if I'd actually seen one. I had, and I'd seen it working well and, yes, I knew about the strangely elastic feel which shouldn't work but does... The Avalon has vastly out performed the Tak EM200 in terms of consitency and overall precision. The Tak gave the best trace I've ever seen but it only gave it once. The Avalon is so consistent.

I'd have a Baby Q on an M Uno in a trice if I didn't have the monster dual FSQ106/Mesu for widefield. A dream setup with 8300 chip.

Olly

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Hello Derek,

A personal observatory would be nice if it weren't for all the street lights, trees and seeing-destroying heated apartment blocks around here. Star parties are basically non-existent in the Netherlands due to the unpredictable weather. Any meteorologist who's right more than half of the time gets banned from the casinos for being too lucky. :grin:

The sensitivity to wind was mentioned in this Cloudynights thread by users Morten and Jesper. But I've done some thinking and not only is Mortens formula for the wind force in post #34 incorrect, he's also not taking into account that the wind will make the scope move around both the RA and DEC axis so the force is divided over two belts. And in the declination axis the wind is acting on both sides of the scope, essentially counteracting itself so the resultant force is lower than calculated. And then there's the lack of backlash. With a conventional worm system the wind will be free to move the scope a bit before the gear engages while a belt will counteract the wind force immediately. Likewise, when the wind has died down the belt system will "snap" back to the correct position while a geared mount may have to clear the backlash first. And finally, with the M-uno the OTA's  essentially moves around its center of gravity while with a conventional GEM the scope will move in an arc around the RA axis. This offset increases the moment of inertia making it more difficult to dampen movement. So my theory is that while a belt driven mount may have more flex, the deviations will last shorter so they register less in the final picture.

I have a trip to Germany planned in October so I think I'll try to squeeze in a visit to Teleskop-Service to take a look at the M-uno in person.

Jarno

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I built a PVC/Tarp wind blocker. It takes less than 5 minutes to set up. I use it with my AVX which is very sensitive to wind and can image in 10 MPH no problem. I will likely do the same when I get the M Uno. 

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Yes Jarno, that is the thread I recall reading. So one disgruntled user (who kept the mount anyway because he still liked it), and some creative math and physics furmulae by his friend don't make a convincing enough argument to condemn the mount (and was the Linear not the M Uno if that matters) in windy conditions. I think Luciano's reply and example were cogent and at least as convincing. Unfortunately there is not a large enough user base to form a conclusion one way or another with this issue. Torsinadoc has the right idea, in building a sturdy wind shield, accepting that most light weight portable mounts will have wind issues.

Derek

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Yes Jarno, that is the thread I recall reading. So one disgruntled user (who kept the mount anyway because he still liked it), and some creative math and physics furmulae by his friend don't make a convincing enough argument to condemn the mount (and was the Linear not the M Uno if that matters) in windy conditions. I think Luciano's reply and example were cogent and at least as convincing. Unfortunately there is not a large enough user base to form a conclusion one way or another with this issue. Torsinadoc has the right idea, in building a sturdy wind shield, accepting that most light weight portable mounts will have wind issues.

Derek

Sure, mounts of normal size will have issues with wind. Perfectly good point. If you go massive, like the Mesu, you can focus one scope of a dual rig by hand, at the focuser, while the other scope is still imaging, and the guide trace will show nothing. But the Avalons are truly portable mounts.

Olly

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By the way, I think anyone trying to write a formula for something as chaotic as the effect of wind on a telescope would have to be optimistic to the point of folly. Think of the variables.

- Turbulence introduced by local objects.

- The angle of the scope relative to the wind, creating a highly variable angle of attack and resulting lift effects.

- Resonance in the mechanical components as wind speed varies.

It's said that on his deathbed Heisenberg was asked if he had any questions for God. He said, Yes, quantum mechanics and turbulent flow. I think I might get an answer on quantum mechanics...

:grin: lly

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I can add my 2 cent about it:

Changing from a Vixen (Nex) SXD to an Avalon Linear I can tell you can have some feeling of "elasticity" at the time you move the scope & watching an object in an eyepiece but it is only a fraction, of a sec.

Comparing to the vixen mount it is a huge improvement because the mount react instantly what was not the case with the vixen mount (backlash).

The mount damping is also better with the same load in my obs. 

Both mounts are good but having no backlash at all is a real pleasure.

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I can add my 2 cent about it:

Changing from a Vixen (Nex) SXD to an Avalon Linear I can tell you can have some feeling of "elasticity" at the time you move the scope & watching an object in an eyepiece but it is only a fraction, of a sec.

Comparing to the vixen mount it is a huge improvement because the mount react instantly what was not the case with the vixen mount (backlash).

The mount damping is also better with the same load in my obs. 

Both mounts are good but having no backlash at all is a real pleasure.

Backlash has been the most persistent problem that I've encountered in guiding since I began imaging ten years ago. That's why I now use a roller drive and a belt drive mount.

Olly

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