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Meade LX850 silence

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#151 galaxy_jason

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Posted 31 May 2013 - 11:50 PM

Despite what people say here the raw PE does not need to be under 10". What counts is the trained PE, if it is a smooth 5" or under it is plenty good enough for Starlock to train out. I have a prototype LX850 with 20" raw and a production LX850 with 7". Both are can product round stars with Sarlock.

#152 OzAndrewJ

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Posted 01 June 2013 - 12:04 AM

Gday Jason

Despite what people say here the raw PE does not need to be under 10". What counts is the trained PE



I fully agree that the Pk-Pk of the PE isnt critical,
its how smoothly it transitions along the way.
However, what interests me more in this design is the higher freq "bumps" in the PE.
With the much larger teeth in the geartrain, i was more interested in what sort of effects they may have, that may not show up clearly in an averaged model like PEC tool etc.
Time will tell.

Andrew Johansen Melbourne Australia

#153 Spacetravelerx

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Posted 01 June 2013 - 12:57 AM

Gday Andrew

and folks are still concerned my plot from the Starlock PEC Utility may have significant errors.



Where has that been said? ie "significant" errors.

Andrew Johansen Melbourne Australia



True, no one has said significant errors, but there seems to be doubts as to the quality or sufficiency of my plot. Still, it is very interesting to see Jason's PEMPro plots matching very close to the Starlock Utility.

Of course in the end, if the LX850 takes amazing images when properly set-up isn't that all that matters?

I sense folks are disregarding the integration of Starlock with the LX850. Yes, it is important to have a very high quality mount on its own merits, hence the interest of the physical mount without the Starlock. But in the end, Starlock and the entire integrated system with the mount is what matters, correct? This means:

-- Excellent guiding
-- Excellent mount
-- Excellent OTA
-- Mechanisms to minimize flexure.

Maybe the entire question everyone is asking is wrong, because the usual model is to buy a mount, find a tripod in some cases, obtain separate software, separate guiding solution, etc. and bring it all together. In the case of the LX850, it is a completely configured, integrated system out of the box which near as I can tell no one else does. Starlock itself is actually two cameras/guiders not one. All the pieces are closely integrated together. You can't have one without the other to get the optimal results.

Maybe the simple question for the AP astronomer is "can the LX850 take an excellent picture"? The claim by Meade is +/- 1 arcsecond guiding - is this not the question we want answered? This is not the mount alone, though it is a critical element. It is based on the entire system. Could this not be solved by taking a 1, 5 and 10 minute pictures and verify in fact this spec is met in good seeing conditions?

The second question is in relation to Meade's claim is the LX850 "can be setup, aligned and imaging in less than thirty minutes". I can in fact verify this to be true, though for the 14" you will get some exercise!

If these two questions are answered, is this not necessary and sufficient for AP?

People want to see the PE data, which is an important subset for the overall integrated system, however in the end is this a necessary parameter to the final answer, or merely part of the equation, which can be managed within a properly designed optimal system? Isn't really the necessary condition "to achieve +/- 1 arcsecond guiding/accurate images"? Isn't this only achieved as an integrated solution?

Think of this - let us say the mount is perfect, but I have a horrible OTA. Then we will never photographically achieve the necessary condition. Think of it another way: some of the satellites I am flying have a range of "observers" and "controllers" with fair to excellent values for accuracy. In the end though the entire control system developed provides excellent controllability and accuracy in pointing.

In the end, I think the two questions are what need to be answered. The LX850 is in fact a complete solution.

If in fact both questions are proven and answered, the LX850 has the potential to be a powerful competitor and the go to solution. Why would I cobble together a high end AP system, when the LX850, itself a high end AP solution, can do it out of the box with an SCT and APO refractor with everything there and easy to operate. And easy is fine - why not optimize the steps for observing and AP?

(There, did it under 10,000 words!).

#154 Pak

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Posted 01 June 2013 - 01:06 AM

Despite what people say here the raw PE does not need to be under 10". What counts is the trained PE, if it is a smooth 5" or under it is plenty good enough for Starlock to train out. I have a prototype LX850 with 20" raw and a production LX850 with 7". Both are can product round stars with Sarlock.


What is the difference between a prototype LX850 and a production one? I know there were differences between the LX800 and the prototype LX850 but what changed between LX850's?

And while you are correct that a mount doesn't need to have less than 10a/s pk-pk of PE, I would add that it is a good measure of the quality of the components and how well they are assembled, adjusted, and implemented. If a production unit is getting 15 to 30 a/s Pk-Pk I really don't care how well PEC works nor do I really care how well Starlock works. I know that there is a mechanical reason that the raw PE is so high and I wouldn't touch it. I am not even really thrilled with the 10a/s to be honest. I'd much rather it be around 5 Pk/Pk for the price Meade is charging for this. CGE-PRO is 5 Pk-Pk and is less than 5K. By the time you add on the Orion autoguider package & Starsense accessory you are still a little less than the LX850 in cost.

I like Andrew's results however I'd really like to see others. Perhaps more data will be forthcoming.

#155 EFT

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Posted 01 June 2013 - 01:34 AM

I frequently have to convince people to look beyond the raw numbers and consider the end result in evaluating their equipment. If not, then no one would ever even try to produce images using mid-level mounts, much less actually produce some excellent images. The raw numbers for mid-level mounts simply easy to view as poor. It is very easy to feel disappointed with a mount that has "poor" PE numbers even though it is possible to produce excellent images with it. That is certainly true with this system as well. What does it really matter what the numbers look like if the end result is good images? I have to agree that for the person who owns the equipment, it makes very little difference. But for the person considering owning the equipment, it makes a world of difference. The numbers are just something that are easy to hang your hat on when making a decision, like weeding out resumes of recent grads on a first pass based on GPA. The reality is that a mount with large but very smooth PE may easily outperform a mount with much smaller but very noisy total error when it comes to imaging, depending on the equipment used. The problem here is actually the LX800, not the LX850.

While people might be difficult to sway with a new design/technology in general, after the first release, it is simply going to be that much harder to change people's perception, and it should be. Neither side is really wrong in their position in this case, it's just how it is because of the past experience. Whether this mount will succeed or fail is yet to be seen, but either way, it is simply going to be harder to convince people of its success. The only thing that will overcome this problem is more data and results from more sources. If not enough people purchase the mount and supply data and results to change people's current perception, that doesn't mean the LX850 is bad, it really just means that the LX800 was bad.

#156 Starhawk

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Posted 01 June 2013 - 02:46 AM

Andrew,

On the star trails method, I've usually been able to get enough movement from a dead reckoning plop down of the mount to get decent trails.

The 30 minutes is just to make sure to get at least three turns of the worm. All the stars in the image will have the same wave form, so it's good to have a range of magnitudes (Usually you will- just don't use a star cluster or nebula and it will work). There's something very visceral I find with this kind of data- I know what my mount did. Even if the Polaris had over 40" RMS, I knew what I was seeing.

The target doesn't need to be a given star- just something with a known image scale in the catalog. So, in my case, I wrote a spreadsheet to take the RA/DEC coordinates of objects and turn them into an angular separation I could use in drive excursion scaling.

I need to root around. I have some darned interesting images from a Vixen Polaris, a Celestron C5+, and a Celestron NexStar SE mount.

-Rich

#157 OzAndrewJ

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Posted 01 June 2013 - 03:01 AM

Gday Andrew

True, no one has said significant errors, but there seems to be doubts as to the quality or sufficiency of my plot.



I would say its more that no one knows one way or another yet.
You mention you design/fly satellites???
When testing them on the ground, do you require your testing equipment to be calibrated???
I merely consider the Starlock PECPlot to be an "uncalibrated tool" at present, no more and no less.

Andrew Johansen Melbourne Australia

#158 OzAndrewJ

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Posted 01 June 2013 - 04:20 AM

Gday Andrew

Still, it is very interesting to see Jason's PEMPro plots matching very close to the Starlock Utility.



I didn't think it was that close, so during a break in the footy, i have cutn pasted Jasons starlock curve, stretched it in the X axis to match the PEMPro plot
and then overlayed it on the PEMPro plot as best i can.
( I'm not good on image processing :( )

To me, the correlation in the middle section isnt good enough to give me a warm fuzzy feeling.
Again, it all comes down to collecting lots of raw data and checking it for consistency.

Andrew Johansen Melbourne Australia

#159 orlyandico

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Posted 01 June 2013 - 05:27 AM

I think the two points are:

1) low raw PE points to good mechanicals

but

2) nobody should care what the PE is, if the LX850 delivers the goods

and while the CGE Pro is allegedly 5" p-p (now 7" I think) and even after adding a guider etc. it still costs less than an LX850, the bottom line is integration costs money.

Crude analogy - an AP or SB mount would be a Swiss mechanical chronometer, which keeps very good time, etc. due to mechanical precision. The LX850 would be a Swiss quartz - equally expensive, but arriving at its performance using electronics. For some people, the idea of spending so much money on a quartz is abhorrent, even though the end result is probably the same or superior (better accuracy, you don't need to buy a winder, no need for annual maintenance..) Those people wouldn't buy an LX850.

At the end of the day, more LX850's will mean everyone will have a better idea of what the technology is capable of. Then people will have a better spread of choices. The mechanical purists still won't buy a Meade. But people who care about results and don't mind the "stigma" of quartz would be happy.

Right now there aren't enough data points (LX850 results) for this argument to be even going on.

#160 freestar8n

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Posted 01 June 2013 - 06:16 AM

I fully agree that the Pk-Pk of the PE isnt critical,
its how smoothly it transitions along the way.
However, what interests me more in this design is the higher freq "bumps" in the PE.



I sure wish everyone felt the same way - because I agree 100%. I do not understand this fixation on "PE" as a measure of performance when autoguiding.

Although high end mounts tend to have low PE, and they can produce good images (small fwhm) - it does not imply a causal connection that lower PE means lower FWHM. The corrections made every 1-3 seconds while autoguiding may be completely dominated by high frequency terms that would swamp a lower frequency "PE" term - and those high frequencies may not even show up in a raw log unless it is captured at high rate, with short exposure times and with an accurate centroid.

The concern for PE is even stranger for the lx850 since it is an integrated imaging system. You can cut to the chase and just study the motion of a star in the image plane while autoguiding - and thereby characterize the guide error over time including flexure and field rotaton. Studying the motion would also help distinguish guiding errors from seeing.

PE plots also don't characterize the response of the mount to guide commands, in terms of latency, backlash, and linear response to pulse times.

I am biased in recommending MetaGuide to record such a log - but it does have inherent advantages in using video analysis to record the centroid every 0.5 seconds, and it has a detailed log with over 30 columns of measurements. All it requires is a decent video camera - and it is a free download. It will work on a mac that can run in Windows mode.

If someone can capture such a log, long enough to record several worm periods, I would be happy to help analyze it in raw form. The logs also work well with PECPrep, for those who want a view of the frequency components.

Frank

#161 Spacetravelerx

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Posted 01 June 2013 - 07:45 AM


While people might be difficult to sway with a new design/technology in general, after the first release, it is simply going to be that much harder to change people's perception, and it should be. Neither side is really wrong in their position in this case, it's just how it is because of the past experience. Whether this mount will succeed or fail is yet to be seen, but either way, it is simply going to be harder to convince people of its success. The only thing that will overcome this problem is more data and results from more sources. If not enough people purchase the mount and supply data and results to change people's current perception, that doesn't mean the LX850 is bad, it really just means that the LX800 was bad.


Ed - I think you hit it spot on.

Without doing the "final pictures", I am so far VERY impressed with the LX850. I really think this is quite a system! And I think Meade has quite a setup with the LX600.

BUT...

BUT...

The drama of the LX800 (and I think LX80) REALLY hit people hard. I was looking at old posts, and there seemed to be a very large and excited audience for the LX800. The drama that ensued was evident.

Now we have following groups:
-- Those that believe in the LX850 concept and are VERY pleased with the results.
-- Those still interested in and believe in the LX850, but need more convincing issues are in fact resolved.
-- Doubters of the LX850 DUE to the LX800 event.
-- Those so burned by the LX800 event nothing will really sway them. General haters are also muddled in here.

The first group, no problems there. The second group? They will buy in once convinced. Third group? LOTS of convincing and sales until they consider to buy in. Last group? May never believe in the LX850. Though I do think the sale of Meade will sway some folks.

Oh there is a 5th group - those oblivious to the LX800 debacle!

#162 Spacetravelerx

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Posted 01 June 2013 - 07:48 AM

Andrew,

On the star trails method, I've usually been able to get enough movement from a dead reckoning plop down of the mount to get decent trails.

The 30 minutes is just to make sure to get at least three turns of the worm. All the stars in the image will have the same wave form, so it's good to have a range of magnitudes (Usually you will- just don't use a star cluster or nebula and it will work). There's something very visceral I find with this kind of data- I know what my mount did. Even if the Polaris had over 40" RMS, I knew what I was seeing.

The target doesn't need to be a given star- just something with a known image scale in the catalog. So, in my case, I wrote a spreadsheet to take the RA/DEC coordinates of objects and turn them into an angular separation I could use in drive excursion scaling.

I need to root around. I have some darned interesting images from a Vixen Polaris, a Celestron C5+, and a Celestron NexStar SE mount.

-Rich


Curious to see your images some time Rich.

I will take a crack at it when I get home - I like the concept of picking a double star.

I don't know if I will plot my LX850 down though! ;)

#163 orlyandico

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Posted 01 June 2013 - 07:53 AM

Frank, the reason for fixation with low PE is that generally, there is a causal link between low PE and good quality mechanics.

It's pretty rare to have a high-PE mount with wonderful mechanicals (old AP1200's and 900's come to mind). But generally if you see a mount with low PE, you have a good confidence level that it's well-made.

#164 Spacetravelerx

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Posted 01 June 2013 - 08:13 AM

Gday Andrew

True, no one has said significant errors, but there seems to be doubts as to the quality or sufficiency of my plot.



I would say its more that no one knows one way or another yet.
You mention you design/fly satellites???
When testing them on the ground, do you require your testing equipment to be calibrated???
I merely consider the Starlock PECPlot to be an "uncalibrated tool" at present, no more and no less.

Andrew Johansen Melbourne Australia




It is certainly possible it is uncalibrated, and being a version 1.0a that is understandable.


Yes, I work with Satellites. I am working on releasing the next generation satellite design tool, and now a Space Hypervisor which will soon be flying on several satellites. And I have a Small Satellite project I am heading up, which we hope to fly in 3-5 years. I have worked on several missions in the past for a range of systems flying on unmanned vehicles and the Space Shuttle.

Testing is a massive effort. I work with flight systems for aircraft too. MASSIVE TESTING. But our budgets are in the millions of dollars for certification, unless little cubesats by universities or small businesses. And yes every thing is calibrated for testing.

I am pretty certain Meade tests things - certainly their optics and such. Though, I highly doubt they design and test software to a DO178B level A requirement (Maybe $100 million per new model/release then, minimum?). Meade has how many programmers? For one flight project we have over 50 and massive processes in place. There is simply not the market size or budgets to support this magnitude of effort.

Where Meade and this industry has the advantage is the ability to evolve existing software over time, strong support of you folks and of course the trickle down of data and tools from Universities, NASA and a range of government agencies (foreign and domestic).


Your point is taken Andrew regarding that it is possible that the Starlock PEC Utility is uncalibrated. Certainly PEMPro has more respect, if anything due to its longevity and improvements and usage over time by the community. The Starlock PEC Utility will get their with the growing number of LX850s and LX600s.

#165 freestar8n

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Posted 01 June 2013 - 08:17 AM

I would put it a different way. High end mounts are made with high end components that are expensive and create very smooth tracking and a very accurately responsive, i.e. guideable, system. This also causes them to have low overall amplitude in their tracking error - but that is on top of the inherent smoother motion and better responsiveness. And that smoother motion allows them to be guided more casually, or not at all, and still get small stars (low fwhm).

But if you just target low PE as the goal and you don't also invest in the expensive bearings and beefy gearboxes that help make high end mounts expensive, you may have a lower PE, but you haven't gained smoother motion and responsiveness.

Low "PE" is mostly determined by the worm and wheel - but there is also the gearbox and quality of bearings that determine the smoothness and lack of high frequency terms. And powerful motors for torque and responsiveness - etc.

This is not to say that you need to spend a lot to get good results - it just says to focus more on tighter and better tuned autoguiding than the peak-to-peak PE amplitude - and use OAG. I think you do need to spend more to get good guiding (small fwhm) *easily* - especially with no guiding at all. But you don't need a high end mount to get small fwhm if you take care to use OAG and good guiding.

With the lx850 it is less tunable and you just get what you get. I'm not sure how much user skill is needed since it is designed to "just work" without special knowledge or skills on the part of the user. Clearly artistic skills are needed to turn the results into a pretty picture - but that is completely separate from the task of capturing good data with the mount in the first place.

Frank

#166 Spacetravelerx

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Posted 01 June 2013 - 08:17 AM

Gday Andrew

Still, it is very interesting to see Jason's PEMPro plots matching very close to the Starlock Utility.



I didn't think it was that close, so during a break in the footy, i have cutn pasted Jasons starlock curve, stretched it in the X axis to match the PEMPro plot
and then overlayed it on the PEMPro plot as best i can.
( I'm not good on image processing :( )

To me, the correlation in the middle section isnt good enough to give me a warm fuzzy feeling.
Again, it all comes down to collecting lots of raw data and checking it for consistency.

Andrew Johansen Melbourne Australia



I get a warmer, fuzzier feeling my self in that the data still looks good.

The PEMPro plot looks very convincing regardless.

Still, it should be easier compare data vs. overlaying graphs which can have issues when scaling. Still, a fun exercise for a basic comparison!

#167 David Pavlich

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Posted 01 June 2013 - 08:19 AM

I frequently have to convince people to look beyond the raw numbers and consider the end result in evaluating their equipment. If not, then no one would ever even try to produce images using mid-level mounts, much less actually produce some excellent images. The raw numbers for mid-level mounts simply easy to view as poor. It is very easy to feel disappointed with a mount that has "poor" PE numbers even though it is possible to produce excellent images with it. That is certainly true with this system as well. What does it really matter what the numbers look like if the end result is good images? I have to agree that for the person who owns the equipment, it makes very little difference. But for the person considering owning the equipment, it makes a world of difference. The numbers are just something that are easy to hang your hat on when making a decision, like weeding out resumes of recent grads on a first pass based on GPA. The reality is that a mount with large but very smooth PE may easily outperform a mount with much smaller but very noisy total error when it comes to imaging, depending on the equipment used. The problem here is actually the LX800, not the LX850.

While people might be difficult to sway with a new design/technology in general, after the first release, it is simply going to be that much harder to change people's perception, and it should be. Neither side is really wrong in their position in this case, it's just how it is because of the past experience. Whether this mount will succeed or fail is yet to be seen, but either way, it is simply going to be harder to convince people of its success. The only thing that will overcome this problem is more data and results from more sources. If not enough people purchase the mount and supply data and results to change people's current perception, that doesn't mean the LX850 is bad, it really just means that the LX800 was bad.


Well stated, Ed! If the images look good, then what's the problem? :shrug:

David

#168 Spacetravelerx

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Posted 01 June 2013 - 08:26 AM

I think the two points are:

1) low raw PE points to good mechanicals

but

2) nobody should care what the PE is, if the LX850 delivers the goods

and while the CGE Pro is allegedly 5" p-p (now 7" I think) and even after adding a guider etc. it still costs less than an LX850, the bottom line is integration costs money.

Crude analogy - an AP or SB mount would be a Swiss mechanical chronometer, which keeps very good time, etc. due to mechanical precision. The LX850 would be a Swiss quartz - equally expensive, but arriving at its performance using electronics. For some people, the idea of spending so much money on a quartz is abhorrent, even though the end result is probably the same or superior (better accuracy, you don't need to buy a winder, no need for annual maintenance..) Those people wouldn't buy an LX850.

At the end of the day, more LX850's will mean everyone will have a better idea of what the technology is capable of. Then people will have a better spread of choices. The mechanical purists still won't buy a Meade. But people who care about results and don't mind the "stigma" of quartz would be happy.

Right now there aren't enough data points (LX850 results) for this argument to be even going on.



Very good point...

Now I am trying to think of a different analogy ;)

#169 Spacetravelerx

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Posted 01 June 2013 - 08:37 AM

Frank,

I will look into MetaGuide.

When I have the data, I will throw it at you and everyone ;)

#170 Spacetravelerx

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Posted 01 June 2013 - 08:56 AM

Frank,

Actually, I do think the LX850 is "tunable". It just makes the process much easier. For example for excellent AP, one needs to drift align (or seems to need to!). The LX850 does this nearly automatically, tracking the drift and then telling the user how much to adjust the alt and/or az of the mount. Now that is cool, and makes life easier. It does provide and option to do this manually though.

You can also tune how aggressive the guiding is. Many other things to tune and play with.

Or...

Just set-up, align and just party. I do agree with Meade that you can have the entire system set-up and fully aligned in 30 minutes (barring the added physical exercise from such a large system).

Of course over time of fine tuning the LX850 things get really easy. I leave my mount setup outside, so it makes for a quick set-up (add OTA, LX850 computer & hand controller, bring laptop, iPad and other toys out and then good to go). When I get home I should be up and running very quickly, barring weather issues.

And I do think the learning curve is easier with the LX850.

We are having fun with this telescope!

Isn't that the point?

#171 freestar8n

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Posted 01 June 2013 - 09:34 AM

Hi-

That's great - I'd be happy to help out if you want to log with MG.

As for tuning - that's great if it has features that allow better results. I knew it must have things like aggressiveness but I'm not sure what else exactly because I don't know what parts are full automated and not meant to be tuned.

I think that for new users a key issue will be getting good focus, and if done manually that does require skill and experience. That will make it even harder to tell the impact of seeing and guiding in images - but I hope it has a means for autofocus as an add-on, if not built in.

Frank

#172 Starhawk

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Posted 01 June 2013 - 12:05 PM

The issue with the LX850 really isn't as simple as, "If someone has gotten a good photo from it, then the mount is good." I will try to recap without a rehash of this particular mount (which isn't productive and I would ask people responding to please not go there).

(1) The mount and its control system are two separate questions. A mount can be mechanically poor or superior separately from its control system being poor or superior. Vixen and Takahashi have wrestled with this duality for years.

(2) At the $6000 price point there has been an expectation of a certain level of mechanical performance from a mount. The important thing about this is this is a very serious level of involvement for an amateur, and few novices start at this level.

(3) Autoguiding started out as a fix for mount tracking. So, the first commercial autoguiders from SBIG were made to produce inputs similar to a manual guidance command by an observer, and that model largely has held up. But because of this, most feel like autoguiding is an add-on accessory to a mount to improve its performance, but the mount really needs to carry its own in mechanical performance before any consideration of how well it can be enticed to perform with guiding seems relevant. A well behaved mount can be made to perform extremely well with guiding.

(4) The LX800 and LX850 have been interpreted by many using other mounts as little more than bundling an autoguiding accessory with a mount and then calling the mount something else.

The elephant in the room has been a discussion I will attempt to illustrate using other brands' equipment, so at least folks can at least see what the issue has been and hopefully avoid a lot of the emotion.

Astro Physic sells a mount called the Mach 1 GTO. It is certified as having better than 7" PE. While it is compatible with autoguiders, no autoguider is provided with it, and the user gets to figure out how to make it run. It's a $6,350 mount head, and you have to get a dovetail clamp, tripod, and power supply separately. The thing is, they have all performed within 7" and the guided performance achieved in the field is on the order of .35."

Notionally, AP could offer the mount with a 50mm guide scope and a guider which would drive the mount out of the box to 1" tracking, but this wouldn't be the reason people bought the mount, and AP doesn't since they know most customers at that level will have their own preferred answers for guiding.

Celestron sells the CGEM for $1400. This mount has decent PE at about 15" in good examples, up to around 25-30", but has been troubled by the infamous 8/3 resonance, which defeats a large portion of its built-in PEC thanks to gearing which requires three worm rotations to repeat its pattern while the PEC repeats every 1 worm rotation. There is no doubt in anyone's mind this mount has no business showing up at a significantly higher price point.

Celestron also sells a separate all-in-one camera and autoguider called Nexguide for $300.

So, the question would be this: If a $1400 CGEM were integrated wth a $60 50mm finder dedicated to feeding a $300 NexGuide unit ($1760 in gear) and the combination proved capable of 1" guided performance, is the combined kit a $6000 mount equivalent to the Astro Physics Mach 1 GTO?

The argument against it is if the mount had really good mechanical performance, then regardless of how well NexGuide did, a serious astrophotograher would add a better autoguider, such as an SBIG second chip camera or an Off-Axis Guider (OAG), and get better performance, anyway. However, if the mount is quite average mechanically, then the ability for a given autoguider to get to 1" performance doesn't mean what it would for the high precision mount, because there is no hope of doing better than that with a better guider. Getting a stock CGEM would be an equivalent investment.

That's what this really all about. The original LX800 had the dire misfortune to have mechanicals which really looked exactly like this situation. As a result, a lot of people expect much better is owed from the LX850.

And what it boils down to is if someone using an OAG or other non-starlock guidng scheme for serious imaging is looking at Mach 1 GTO territory (as the price would suggest), or if it is something less? As of yet, there hasn't been anything mentioned to suggest Starlock should be somehow better than other autoguiders, and it can't do the off axis trick anyway, so the mount's drive behavior is the only question about the LX850 anyone cares about.

Andrew, since you came into this late, I suggest you go back and read the threads on the LX800 so at least you'll see where this came from, and why no one's issues are with the finish, the bundled software, or which OTAs are available or not.

Let us please continue to have a civil discussion, and keep in mind Meade appears to have the prospects of a large change in management, so rehashing past events isn't productive. The question this thread is trying to answer is, "Where are we, now?"

-Rich

#173 David Pavlich

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Posted 01 June 2013 - 01:32 PM

You only left out one item, Ritch: The LX850 is rated for 90lbs. That does make a difference. Move up to a 90lb capacity in the world of AP or Tak, suddenly the story becomes different when we consider dollars.

David

#174 Starhawk

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Posted 01 June 2013 - 01:39 PM

David- a very good point. Do we have any history of using the LX850 at or near its rated payload?

I don't recall anyone reporting trying that with an LX850.

-Rich

#175 WadeH237

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Posted 01 June 2013 - 02:38 PM

You only left out one item, Ritch: The LX850 is rated for 90lbs. That does make a difference. Move up to a 90lb capacity in the world of AP or Tak, suddenly the story becomes different when we consider dollars.

David


The LX850 appears to be a clone of the Astro-Physics Mach1. So why does the LX850 have a 90lb payload rating and the Mach1 a 40lb rating?

Here's my answer to that:

The maufacturer's capacity rating on a mount is a pure marketing number. Meade's marketing department has a long established history of stretching these numbers as far as they can (remember that they sold an 10" Schmidt Newt on an LXD-75?) Astro-Physics has a long established history of conservative ratings on their mounts. In the case of the Mach1, they have an extra incentive to be conservative to avoid eating into AP900 sales. It is not unheard of to see people running a Mach1 with 100lb of payload.

Given the mechanical similarities, do you really think that Meade has improved the real world capabilities beyond the Astro-Physics? Or is it more likely that both companies are just rating their equipment they way that they normally do and arriving at different numbers?

Until the LX850 has been out there long enough to see some side by side comparisons with the Mach1, it seems wise to take the difference in capacity with a giant grain of salt.

Even though I am not in the market for an LX850, and likely won't ever be, I think that a healthy Meade is good for astronomy. Their pending acquisition will hopefully give them solid financial footing, and I am optimistic that the LX850 will deliver on its promises (when the LX800 problems became apparent, I even stated on some of these threads that Meade would make it right).

Like many others, I am curious to see some real world data on how these mounts perform (thanks to Jason for what he's said so far). On the specific topic of this thread, I don't actually see it as a concern that there's not been much so far, though. The CGE Pro had a similar quietness when it came out, but it's matured pretty nicely. To me, the real story will be told when we start seeing images in the DSLR and CCD imaging forums taken from this platform.

-Wade



-Wade


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