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AZ EQ6 in the US?

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#51 Lee Jay

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Posted 21 November 2012 - 11:14 PM

Bingo! 20 out of 20x4min turned out to be perfectly round :jump: 100% crop with 200/900mm Newton, guided with OAG and MGEN. Very happy indeed so far!!

CS
Martin


Impressive. Thanks for posting.

#52 jrbarnett

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Posted 22 November 2012 - 12:11 AM

Nice tracking Martin. I think you have a winner!

Regards,

Jim

#53 ccs_hello

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Posted 22 November 2012 - 08:53 AM

Those motors look like their nice and big, no wonder the amp draw is more. Now that looks like a mount that can move my ota with ease even if it's out of balance.
I'm really starting to like this mount. But someone else is going to have to do all the testing on this one before I buy another new design.

neilson


Nelson,

AZEQ6 is using the same microstepping driving system as in the EQ-G EQ6. Its mechanical gear down is rather minimum thus a high current, high toque stepping motor is required. I.e., it's a necessity not over-engineering. Mount overload is not a desirable thing since it will cause "driving pulse slip (i.e., hear the horrorable buzzing sound)". Mount will lose its GOTO position, but no actual mechanical gear wearing (which is good after all).

Clear Skies!

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#54 Lee Jay

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Posted 22 November 2012 - 10:24 AM

Those motors look like their nice and big, no wonder the amp draw is more. Now that looks like a mount that can move my ota with ease even if it's out of balance.
I'm really starting to like this mount. But someone else is going to have to do all the testing on this one before I buy another new design.

neilson


Nelson,

AZEQ6 is using the same microstepping driving system as in the EQ-G EQ6. Its mechanical gear down is rather minimum thus a high current, high toque stepping motor is required. I.e., it's a necessity not over-engineering. Mount overload is not a desirable thing since it will cause "driving pulse slip (i.e., hear the horrorable buzzing sound)". Mount will lose its GOTO position, but no actual mechanical gear wearing (which is good after all).

Clear Skies!

ccs_hello


On this mount, it wouldn't lose its goto position due the dual-axis encoders, correct?

#55 EFT

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Posted 22 November 2012 - 01:01 PM

According to the daily digest a user by the name of "smee" posted a big long review of his new AZ-EQ6 but I cannot find the new thread or the post in an old thread anywhere. Anybody know where it ended up?

#56 ccs_hello

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Posted 22 November 2012 - 04:42 PM

On this mount, it wouldn't lose its goto position due the dual-axis encoders, correct?


The encoder resolution is much more coarse 3.4 arc-min per tick. So for sure, the encoder is not used for closed-loop servo position tracking.
Encoder is only used in manual push-to situation.

I.e., view such design as a hybrid solution, either GOTO or PUSH TO, but not a combined solution.

Clear Skies!

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#57 Lee Jay

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Posted 22 November 2012 - 06:34 PM

On this mount, it wouldn't lose its goto position due the dual-axis encoders, correct?


The encoder resolution is much more coarse 3.4 arc-min per tick. So for sure, the encoder is not used for closed-loop servo position tracking.
Encoder is only used in manual push-to situation.

I.e., view such design as a hybrid solution, either GOTO or PUSH TO, but not a combined solution.

Clear Skies!

ccs_hello


Right, isn't that what I said? It wouldn't lose it's GOTO position, same as if you manually pushed it somewhere.

#58 ccs_hello

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Posted 22 November 2012 - 09:48 PM

AZEQ6 GOTO resolution is 0.140625 arc-sec/microstep, while PUSH TO is 3.4 arc-min/tick. The difference is 1451:1 thus PUSH TO is not so useful in regaining GOTO positioning. Roughly, perhaps; in precision, no.

#59 Mike X.

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Posted 22 November 2012 - 11:25 PM

You have a point on that.nevertheless I believe for visual use in alt/az mode could be valid even for not doing the entire alignment process from scratch.
In eq mode probably the most interesting parts are the belt driven gears,the altitude adjustment mechanism,the thicker counterweight shaft could also be of some extra help and the slightly larger gears...92,5mm of D instead of 90...but this has all to be proven in the field.
Does all that justifies the extra money instead of a regular atlas? I don't know..But if someone is intending to add a thicker counterweight shaft on the atlas like the geoptik for example or upgrade the altitude bolt...etc..etc...and the new mount performs the same it could be a valid alternative probably.

#60 Lee Jay

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Posted 22 November 2012 - 11:38 PM

AZEQ6 GOTO resolution is 0.140625 arc-sec/microstep, while PUSH TO is 3.4 arc-min/tick. The difference is 1451:1 thus PUSH TO is not so useful in regaining GOTO positioning. Roughly, perhaps; in precision, no.


The point is, goto accuracy is in the multi-arc-minute range anyway, and pushing is no different from stepper motor slipping.

#61 neptun2

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Posted 23 November 2012 - 02:41 AM

I see that this new mount have permanent PEC. does that mean that we can use for example PEMPro to train the mount and store the information in the hand controller or this will not be possible?

#62 johnpd

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Posted 23 November 2012 - 07:18 AM

That is interesting. I saw the post. It apparently has been deleted.

JohnD

#63 rmollise

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Posted 23 November 2012 - 08:00 AM


The encoder resolution is much more coarse 3.4 arc-min per tick. So for sure, the encoder is not used for closed-loop servo position tracking.
Encoder is only used in manual push-to situation.

I.e., view such design as a hybrid solution, either GOTO or PUSH TO, but not a combined solution.

Clear Skies!

ccs_hello


Not really. Its intent is to provide just that, a combined system. Like the old Ultima 2000, go-to a target, then push to something without losing your alignment. ;)

#64 TMSP

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Posted 24 November 2012 - 01:09 PM

Looking at the discussion on the GOTO v. encoders as relates to on/off GT and push.

Appreciate the technical commnets, but don't understand. So, I am thinking about what works in the field. I started to map the options, but post to long. Basically, wonder how this will be managed and any options to "realign" (like the Meade program does) or otherwise handle. First reviewers, could you give us your thoughts? Does it work?

I set up GT, I use Handbox to choose and slew obtects. Now I want to do a long slew and impatient becauses its too slow (is it?), too noisy (is it) or I want to drive myself.

I imagine there is some "disengage" as simple as turning a clutch (no software buttons to pusH) and I speed across the Universe to the opject I want if viewable or close to it if I know the position.

What NOW? Engage, punch up the object and let the Handbox take over? Or,

If I center the obect manually and then turn to GT a

#65 ccs_hello

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Posted 24 November 2012 - 02:58 PM

TMPS,

1451:1 precision difference is about 1 mile vs. 1 yard.
Let's think about one axis (or one dimension) approach on this positioning precision problem.

Think about you've built a robot-car capable of driving on an Interstate Highway. With initial (3-star) alignment, it knows exactly the robot's position relative to the Highway's milepost.

If the robot is keeping track on yard measurement, if there is no slippage, the robot can drive for 321 miles 123 yard from milepost zero, its position should be 321 mile 123 yard. But if you disable the yard measurement method (or discard the result), all the robot can count is the milepost sign number with the precision of one mile range. So with the latter, it will know it's somewhere close to 321 mile +- 0.5 mile, but no more precision.
Would it be good enough? That's individual user's call.

Let me also provide a hint, if coarse precision is good enough for a GOTO system, how come there is no commercial GOTO system being built with that type of design (or will that vendor survive in a competitive world?)

My 0.02.

Clear Skies!

ccs_hello

#66 Lee Jay

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Posted 24 November 2012 - 05:29 PM

Let me also provide a hint, if coarse precision is good enough for a GOTO system, how come there is no commercial GOTO system being built with that type of design (or will that vendor survive in a competitive world?)


There are, and this is one of them. These encoders are designed for goto only, and the accuracy is to get the object into the field of view of the eyepiece. These are plenty good for that. Many systems have this feature.

Go here and start watching the video at 5:15 or so for an example of another system like that.

#67 ccs_hello

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Posted 24 November 2012 - 06:08 PM

Yeah, he used the term: closed loop system on that XX16g. I'd call it a "rough closed loop" system instead for the reason I mentioned before.

P.S. when I said "that type of design" I meant a GOTO system only gives out arc-min type of resolution natively. (Yes I know that by using "push to" to ruin the precision resolution, the "rough" position can still be recovered.)

#68 ccs_hello

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Posted 24 November 2012 - 06:11 PM

PPS. one way to regain precision positioning after the PUSH-TO is to inform the handbox the star (with its position known in the database) is now centered in the field. This would be similar with the one-star alignment.

Also, if encoder tick is precision enough (just like the milepost example), in the next GOTO, the handbox algorithm may use it to regain the precision position reference.

#69 Lee Jay

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Posted 24 November 2012 - 07:06 PM

Above you posted this. "The encoder resolution is much more coarse 3.4 arc-min per tick."

Well, that should be plenty for goto. Picking an extreme, a 50 degree APOV eyepiece at 600x is showing you 5 arc minutes of sky. Getting gotos to +/- 1.7 arc minutes would be great performance as it would have objects in the field of view of that extreme situation.

The high-precision stuff (either from the encoders/pulse counters on the motors or on really expensive systems by having high-precision encoders) is for accurately controlling speed and for guiding. For gotos, these encoders should be just fine, and they should enable a recovery from a slip or a push. Not that you should every cause the steppers to slip, but stuff happens you know.

#70 rmollise

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Posted 25 November 2012 - 10:43 AM

The high-precision stuff (either from the encoders/pulse counters on the motors or on really expensive systems by having high-precision encoders) is for accurately controlling speed and for guiding. For gotos, these encoders should be just fine, and they should enable a recovery from a slip or a push. Not that you should every cause the steppers to slip, but stuff happens you know.


Exactly. If properly executed, this will work more than well enough. ;)

#71 martl

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Posted 25 November 2012 - 03:09 PM

Quite a lot of speculation going on here...In Europe the EQ6AZ costs about the same than a normal CGEM, but an illuminated polar scope comes as standard. The mount is, as far as I can judge after one test, cleverly designed. The altitude adjustment with only one screw is superior to the screw&counterscrew adjustment I have seen on many other mounts, because you can easily operate it with one hand with little force applied. Also the slip clutches are a very cool thing. First, the handles are always at the same position (anybody, who has tried to locate RA and Dec clamps in the dark while stabilizing the scope in that position will appreciate this greatly). Second, the danger of applying too much force to the worm block(e.g. if somebody bumps accidentially the tube or counterweights in the dark and believe me, this can happen! :o) is reduced. The additional encoders may only be a consequence of the slip clutches to prevent the alignment from getting lost (it is of course easier to shift a telescope with slip clutches accidentially than with locking srews tightened down fully). Anyway, this is my first goto telescope and I didn't put my focus on goto precision, but rather wanted to test the guiding accuracy. This is what really counts if you want to do astrophotography, and the results exceeded my expectations. RA is very smooth, and the response in DEC to the autoguiding signals is very fast even if they change direction due to small overshooting. If weather permits, I will carry out further tests, but so far I don't regret bying this mount a second.
CS
MArtin

#72 Lee Jay

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Posted 25 November 2012 - 03:24 PM

More than one site in Europe also reports the payload capacity as 25kg. Any thoughts on that?

#73 martl

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Posted 25 November 2012 - 05:04 PM

Well, maybe if you are using a SC/RC or another short tube system on a permanent pier. I wouldn't mount a C14 on that, but if the CGEM can handle a C11, the EQ6AZ should be capable of doing this also.

CS
Martin

#74 Lee Jay

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Posted 25 November 2012 - 05:40 PM

Well, maybe if you are using a SC/RC or another short tube system on a permanent pier. I wouldn't mount a C14 on that, but if the CGEM can handle a C11, the EQ6AZ should be capable of doing this also.

CS
Martin


Well, a C11 weighs 27 pounds, and a C14 weighs 46 pounds. 25kg = 55 pounds. This guy (above) mounted a 37.5 pounds Newtonian and got great results tracking with OAG. I'm wondering if a C14 is really out of the question without lots of auxiliary components and for planetary imaging.

#75 TMSP

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Posted 25 November 2012 - 05:54 PM

martl:

Thanks for your comments on the mount. Yours is the first report I have seen from a buyer. I mostly observe, so the push to is interesting feature, but does it work to keep alingment in the field and what is done to get it realigned is needed? Have you seen the manual for the SynScan? I understand it somewhat different in features to accomadate both AltAz and Eq. Thanks for any further comments as you have time and inclinations. I am looking hard at dropping $$ on one and appreciate any insight.






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