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which mount should i get?

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#1 Hestemat

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Posted 30 March 2014 - 10:30 AM

Hey ive ordered an AT65EDQ scope, looking for an EQ mount with guide ability, have my eyes on Advanced VX

but anyone got some cheaper that is just as good or good enough to be considered instead?

note: im shooting with a 550D dslr

#2 terry59

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Posted 30 March 2014 - 11:47 AM

The AVX mount has no DEC axis bearing. Good for visual, not for AP.

#3 RTLR 12

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Posted 30 March 2014 - 11:57 AM

The AVX mount has no DEC axis bearing. Good for visual, not for AP.


I, and thousands of others, have been doing AP with the AVX's predecessor CG-5 that also has no DEC bearing for many years. There are many members here on CN that are doing AP with the AVX with great results. The lack of a DEC bearing does not rule the mount out as far as AP is concerned.

Stan

#4 lurkinggrue

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Posted 30 March 2014 - 01:58 PM

Not arguing about the AVX and AP, just curious. Does the CGEM have a dec bearing? (asking because I am in a great conflict about which to get CGEM vs AVX for AP)

#5 RTLR 12

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Posted 30 March 2014 - 03:14 PM

Yes, 3 actually.

Stan

#6 Mkofski

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Posted 30 March 2014 - 03:25 PM

Hey ive ordered an AT65EDQ scope, looking for an EQ mount with guide ability, have my eyes on Advanced VX

but anyone got some cheaper that is just as good or good enough to be considered instead?

note: im shooting with a 550D dslr


Have you considered the iOptron zEQ25? It's not cheaper but isn't as heavy as the AVX and is probably better for unguided work. It has a guide port like the AVX. I don't think you find anything new for less than the AVX that will work for AP.


Mike

#7 terry59

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Posted 30 March 2014 - 06:51 PM

The AVX mount has no DEC axis bearing. Good for visual, not for AP.


I, and thousands of others, have been doing AP with the AVX's predecessor CG-5 that also has no DEC bearing for many years. There are many members here on CN that are doing AP with the AVX with great results. The lack of a DEC bearing does not rule the mount out as far as AP is concerned.

Stan


Stan I said it wasn't good for it, not that it or any mount without a DEC bearing wasn't usable....people do it all the time. I just won't recommend them for AP. I can't see complicating the learning process intentionally

#8 orlyandico

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Posted 30 March 2014 - 07:26 PM

Ironically all of the Vixen GP mounts don't have bearings either. But people have been doing AP with them for decades.

#9 oo_void

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Posted 30 March 2014 - 09:18 PM

Not arguing about the AVX and AP, just curious. Does the CGEM have a dec bearing? (asking because I am in a great conflict about which to get CGEM vs AVX for AP)


Even though I'd normally pick a CGEM over the AVX, The CGEM might be a bit heavy for such a little scope making it hard to balance.

#10 guyroch

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Posted 30 March 2014 - 09:26 PM

In between the CGEM and the AVX sits the proven Orion Sirius / SkyWatcher HEQ5.

Just a thought.

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#11 RTLR 12

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Posted 30 March 2014 - 09:42 PM

Not arguing about the AVX and AP, just curious. Does the CGEM have a dec bearing? (asking because I am in a great conflict about which to get CGEM vs AVX for AP)


Even though I'd normally pick a CGEM over the AVX, The CGEM might be a bit heavy for such a little scope making it hard to balance.


I have to use a 7¬Ĺ lb CW to balance my SV70 on my CGEM and I use 2" diag and some heavy EP. (Ethos)

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#12 Hestemat

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Posted 30 March 2014 - 11:46 PM

Thanks, seems like i cant care about the bearing as then the price goes way up. Ive seen alot of pics with pinpoint stars shot with an avx, cant do much better than that. May be a little harder but thats ok.

#13 RTLR 12

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Posted 31 March 2014 - 12:48 AM

If it was easy, every one could do it!

Stan

#14 Hestemat

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Posted 31 March 2014 - 02:40 AM

Exactly, hard makes it fun. Can make decent unguided shots with my nexstar 4se in modified eq stand

#15 Hestemat

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Posted 31 March 2014 - 04:10 AM

Also wouldnt a heavier scope be more problem for the lack of a bearing?

With this light scope with a 50mm guidescope wouldnt pressure the dec that much, seen AP being done on this mount with 10" newts without mich of a problem

#16 Eddgie

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Posted 31 March 2014 - 09:25 AM

The AVX mount has no DEC axis bearing


I believe this is incorrect. It may not have a "Ball Bearing" but it does have a sleeve bearing.

Sleve bearings are in fact quite suitable to the task of holding a telescope in a low speed operation.

In fact, a plain bearing has far higher load capacity than a roller bearing because the area.

In these scopes, the worm wheel is meachined into a large aluminum cylinder, and the outside of this cylinder rides on the sleve bearing in the casting.

Nothing wrong with this setup. Plain bearings are used in many important applications and have proven themselves as being very capable.

Just my opinion, but to say a mount is less than acceptable because it does not use a roller bearing in place of a plain bearing seems to me a bit unwarrented. I am confident that used within loading parameters (and that is why people publish load parmaters) the bearing will last a liftetime.

And the motors have far more torque than required to overcome the greater friction of a plain bearing.

But my main intention of resonding to your post was to say that the mount does indeed have a bearing. Just not a roller bearing.

#17 terry59

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Posted 31 March 2014 - 09:36 AM

The AVX mount has no DEC axis bearing


I believe this is incorrect. It may not have a "Ball Bearing" but it does have a sleeve bearing.

Sleve bearings are in fact quite suitable to the task of holding a telescope in a low speed operation.

In fact, a plain bearing has far higher load capacity than a roller bearing because the area.

In these scopes, the worm wheel is meachined into a large aluminum cylinder, and the outside of this cylinder rides on the sleve bearing in the casting.

Nothing wrong with this setup. Plain bearings are used in many important applications and have proven themselves as being very capable.

Just my opinion, but to say a mount is less than acceptable because it does not use a roller bearing in place of a plain bearing seems to me a bit unwarrented. I am confident that used within loading parameters (and that is why people publish load parmaters) the bearing will last a liftetime.

And the motors have far more torque than required to overcome the greater friction of a plain bearing.

But my main intention of resonding to your post was to say that the mount does indeed have a bearing. Just not a roller bearing.


I stand corrected and should choose my words more carefully. However, I stand by my assessment that this type of mount is not a good choice for AP.

#18 gdd

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Posted 31 March 2014 - 09:49 AM

The AVX mount has no DEC axis bearing. Good for visual, not for AP.



Is it safe to say you may not need to make any DEC corrections with the AVX because it is a small mount you are more likely to use for wide field AP? But if you try overload the mount it may become an issue?

Gale

#19 andysea

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Posted 31 March 2014 - 09:52 AM

Hey ive ordered an AT65EDQ scope, looking for an EQ mount with guide ability, have my eyes on Advanced VX

but anyone got some cheaper that is just as good or good enough to be considered instead?

note: im shooting with a 550D dslr


Are you going to have to travel to dark sites to image? If so portability and ease of setup/polar alignment may be one of the deciding factors when picking a mount.
I have to travel and I used to image with a mount that weighs 55lbs for the head only. Its payload was way beyond any of my scopes. I am much happier now with a lighter mount that still offers the same accuracy but it's much easier to setup and carry around.

#20 keithlt

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Posted 31 March 2014 - 09:54 AM

I'm sure Celestron expected them to be used for AP as they come with an auto-Guider port. Eddgie makes a valid point about the sleeve bearings, I would not be surprised if the little DC drive motors in most every mount is of sleeve bearing design.

#21 Hestemat

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Posted 31 March 2014 - 09:57 AM

Thanks! Now it sounds even better. I dont plan on traveling with it, but if it comes up, do you mean this is too heavy?

Im not set on this scope for the rest of my life, i like to have a mount that can take heavier loads down the road.

#22 Hestemat

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Posted 31 March 2014 - 10:04 AM

And also, sounds really wrong to say this mount isnt good for AP, i understand it isnt the BEST for AP, but i will never have the best.

Its for wide field AP yes, havent understand what to picture in the opposite :p

#23 ur7x

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Posted 31 March 2014 - 10:20 AM

The AVX mount has no DEC axis bearing. Good for visual, not for AP.



Is it safe to say you may not need to make any DEC corrections with the AVX because it is a small mount you are more likely to use for wide field AP? But if you try overload the mount it may become an issue?

Gale


If you overload just about any mount you will have issues with AP.

Speaking as someone who actually owns both mounts and has imaged with both of them. I would tend to agree with Eddie, the ASGT and AVX Dec "bearing issue" is somewhat overblown. Given a decent polar alignment even at full F/10 of my 9.25" scope I can, and have, produced some very nice results (a quick Google search will net several others who have too)

Granted I'm discarding about 1 sub in 10... And Granted there are several better AP mounts out there... most of them are at least double the cost and some are an order of magnitude more expensive.

If anyone wants to get started in this hobby and would rather not drop several thousand on a mount, and wants something that is almost "grab and go" light... the AVX is a fine choice.

Of course the CGEM has its issues too... With its 8/3 design error. Of course I have never run into this problem and have good results with this mount too. But it is a heavy beast and for me it is too heavy to take with me to my favorite dark sky location.

Back to the AVX, keep the load under 30 pounds and you should have no problems producing some really impressive results. My 9.25 with camera and guider is pretty much the upper limit.

#24 RTLR 12

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Posted 31 March 2014 - 10:24 AM

I stand corrected and should choose my words more carefully. However, I stand by my assessment that this type of mount is not a good choice for AP.


Terry,

Do you own a CG-5 or AVX mount and if so have you done AP with it?

Stan

#25 orlyandico

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Posted 31 March 2014 - 11:09 AM

The AstroPhysics 600E mount which Zeiss saw as fit enough to rebadge as Zeiss PaMont II, has sleeve bearings in both axes.

I have had a lot of trouble guiding mine in declination due to stiction. So yes roller bearings can be better than sleeve bearings. But by no means are sleeve bearing mounts unsuitable. Like I said the Vixen GP and GPDX use sleeve bearings. And no one would call a GPDX unsuitable for AP.






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