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Jason Ware's LX800

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#51 andysea

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Posted 08 December 2012 - 08:40 PM

The clutches on my Mach1 are pretty stiff and that's just normal. The Njp axes spin completely loose when the clutches are released. It's just different designs but there is nothing wrong with either one, at least nothing that I am aware of.
 

#52 andysea

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Posted 08 December 2012 - 08:52 PM

In my experience an OAG gives the best guiding possible, however I am not sure how an OAG could be integrated into a mount/OTA. The OAG needs to be setup in such a way that the guide camera comes into focus at the same point as the imaging camera. Backfocus of DSLR's and CCD cameras varies a lot and it would be nearly impossible to provide an integrated OAG that works out of the box with any imaging system. Not to mention the high price tag of a decent guide camera that is sensitive enough to work with the OAG.
 

#53 korborh

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Posted 08 December 2012 - 11:53 PM

I wish Meade had gone with an OAG solution rather than a small guide scope


Hmm? As if finding a guide star with OAG could be easily automated.


One can Calibrate FOV in TheSky and use a Rotator with one of the many automation programs. I have never used a rotator so not sure how easy this is in practice.
I rotate manually and the guide star is there because my FOV and OAG angle is calibrated.
 

#54 andysea

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Posted 09 December 2012 - 12:07 AM

So far with my lodestar, in over a year of imaging, I never had to rotate the oag to find a guide star.
 

#55 Peter in Reno

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Posted 09 December 2012 - 12:11 AM

Same here. Never had to hunt for guide star with OAG and Lodestar using C-8 at 2000mm focal length.

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#56 Alph

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Posted 09 December 2012 - 01:52 AM

One can Calibrate FOV in TheSky


How would you automate it? Is the Meade LX200 controller able to run TheSky?
 

#57 Hilmi

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Posted 09 December 2012 - 05:09 AM

I think that should they be able to resolve all the problems before their financial troubles drown them, starlock could prove very popular with people who would like to get into Astro-photography but are intimidated by coming up with a package and integrating it and working out the bugs. I also believe it will be a huge hit with DSLR imagers. 100% PC free imaging out of the box, no extra gadgets needed.

Looking at the resutls so far, maybe it will work better wit slightly shorter focal lengths.

At this price range, the lure is in the simplicity, that is what you are paying a premium for. And honestly, even if the first generation of the technology might not be perfect, the second generation might hit the sweet spot and be a major game changer in the industry.
 

#58 freestar8n

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Posted 09 December 2012 - 06:30 AM

I am not optimistic about any system that guides a large sct with a separate guidescope because differential flexure is fundamentally difficult to overcome due to the ota itself and its two reflecting surfaces. On the other hand, the system could work very well for guiding a refractor, and the 130mm apo version of the lx800 at the same price as the 12" ($9999) makes perfect sense as an integrated system that should do well out of the box, and be easy to use. None of the images I have seen with lx800 and a large sct show any benefit of the greater aperture and I think better results would be achievable with a well-focused 130mm refractor - and it would be much easier to operate.

If there are compelling results guiding a large sct with a guidescope system, then the performance can be summarized in two numbers: the achieved fwhm (arc-seconds) in longish exposures (preferably 5-15m) and the flexure rate in arc-seconds per minute. Anyone characterizing the performance of such a system should be measuring those numbers, and if the results are good - I would prefer to see the numbers and example sub-exposures rather than just a final processed image with no measurements.

The measure of a well guided image at long focal length isn't just "round" stars, but small and round stars. If the stars are large and round, it could be due to poor focus and/or guiding, and the size of the stars will mask both flexure and field curvature. If the stars are very small, then the effects of flexure and field curvature become much more noticeable.

Regarding OAG, I think it is essential if you want to realize the full potential of a large aperture sct. I don't think it could be easily offered in some automated form, mainly because of the difficulty in maintaining focus on the guide chip. At the same time it is not that difficult to use once the system is configured, particularly with a sensitive ccd guide camera and a smooth mount that can tolerate long guide exposures.

Regarding the helix image - I have never imaged it myself because it is at -20 declination, and not an easy target from mid-northern latitudes. Even from Dallas it's an odd choice if seeing conditions aren't optimal, and the other examples of pac-man and crab make more sense.

Frank
 

#59 Lee Jay

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Posted 09 December 2012 - 10:23 AM

I am not optimistic about any system that guides a large sct with a separate guidescope because differential flexure is fundamentally difficult to overcome due to the ota itself and its two reflecting surfaces.


I am, but they've got to produce the f/5 reducer. Even with the f/8 scopes and the lower read noise sensors we're starting to get, shorter subs are becoming more and more practical. They don't need to get rid of differential flexure, they just need to keep it to a low enough level during the sub exposure, and if the subs are getting down into the 30-300 seconds area, it shouldn't be too difficult to make that happen.
 

#60 Peter in Reno

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Posted 09 December 2012 - 11:40 AM

What about narrow band imaging? It usually requires a significantly longer sub exposure at a minimum of 15 minutes up to 30 minutes. NB imaging is getting very popular especially for light polluted skies.

Peter
 

#61 Lee Jay

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Posted 09 December 2012 - 12:27 PM

What about narrow band imaging? It usually requires a significantly longer sub exposure at a minimum of 15 minutes up to 30 minutes. NB imaging is getting very popular especially for light polluted skies.

Peter


Good point.
 

#62 galaxy_jason

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Posted 09 December 2012 - 03:04 PM

Look at my web site. I do 10 minute subs at f8 from Dallas in HA, SII and OIII. 30 minute subs are not needed.

One thing I forgot to mention, on both mount samples I have seen so far the declination backlash is almost non-existent :)
 

#63 ahopp

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Posted 10 December 2012 - 09:09 AM

Great work Jason.

Tony
 

#64 Starhawk

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Posted 10 December 2012 - 06:58 PM

I was trying not to go there, but if one were trying to conceal tracking errors, far southern targets and big, blobby stars are a good start.

-Rich

The measure of a well guided image at long focal length isn't just "round" stars, but small and round stars. If the stars are large and round, it could be due to poor focus and/or guiding, and the size of the stars will mask both flexure and field curvature. If the stars are very small, then the effects of flexure and field curvature become much more noticeable.

Regarding OAG, I think it is essential if you want to realize the full potential of a large aperture sct. I don't think it could be easily offered in some automated form, mainly because of the difficulty in maintaining focus on the guide chip. At the same time it is not that difficult to use once the system is configured, particularly with a sensitive ccd guide camera and a smooth mount that can tolerate long guide exposures.

Regarding the helix image - I have never imaged it myself because it is at -20 declination, and not an easy target from mid-northern latitudes. Even from Dallas it's an odd choice if seeing conditions aren't optimal, and the other examples of pac-man and crab make more sense.

Frank


 

#65 Lee Jay

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Posted 10 December 2012 - 08:29 PM

I was trying not to go there, but if one were trying to conceal tracking errors, far southern targets and big, blobby stars are a good start.


This is a tight crop of one of Jason's images. Does this meet the criteria you expressed above?

Attached Files


 

#66 Mkofski

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Posted 10 December 2012 - 08:42 PM

Rich,

Think you should have tried harder not to go there. I'm not sure what would be gained for Jason or for Meade if the results were not on the level. With all the problems with the LX800 early this year a second round of bad results would be the end of the product... IMO.
 

#67 galaxy_jason

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Posted 10 December 2012 - 09:42 PM

Yep, that's it. I picked low targets to get big blobby stars to hide tracking errors. As they say on Monday night football. Come on man.
 

#68 David Pavlich

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Posted 10 December 2012 - 10:19 PM

Time for a cool off. It's locked for the time being.

David
 

#69 David Pavlich

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Posted 11 December 2012 - 10:47 AM

Unlocked. Let's see if we can behave.

David
 

#70 ahopp

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Posted 11 December 2012 - 10:56 AM

Jason,

Can you compare the performance so far with the LX800 to other platforms you have used? I am a patiently waiting recall customer of the 14".

Tony
 

#71 freestar8n

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Posted 11 December 2012 - 11:22 AM

I only mentioned the low dec. of Helix because someone had requested comparison images. My note prior to that request had specifically pointed to my comparison image of the Crab, and at the same site I additionally have images of Pac-man - and many others. So regarding the specific request for comparison helix images - it is not as common or popular a target from mid-northern latitudes as many other options.

For comparing one system to another in terms of guiding and so forth, I place more value on 1) fwhm in arc-seconds, 2) raw, linearly stretched sub-exposures, and regarding flexure, 3) a measured rate in arc-sec/minute of the flexure. This can be determined from successive plate solves of the sub-exposures directly - assuming no polar rotation. And for best results that capture the guiding capability of the system, I would use an object up from the equator but not too far, so it is in steadier atmosphere but not so far from the equator that it is moving slowly across the sky.

I don't think these are unreasonable things to request since I provide similar information to convey my own autoguiding results. I also provide a video-based tool for realtime analysis of flexure rates - as a free download. A typical sct flexure rate with a guidescope might be 0.1-0.3" per minute - which is tolerable in a 5-minute exposure if the stars are perhaps 4" in diameter, but when they are 2" it becomes a problem that limits exposure time. I don't concern myself with flexure much since I switched to OAG.

For a refractor, flexure tends to be much smaller, and it is harder to get 2" stars in the first place - which is why I thought a refractor, using starlock on lx800, might be a better setup for someone who wants a turn-key imaging system that captures results close to the limit of the optics used.

Frank
 

#72 Starhawk

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Posted 11 December 2012 - 02:09 PM

My comment was geared towards producing an engineering test of the mount. The emotionally charged response isn't relevant to the issue at hand: performing an unambiguous evaluation of the LX800.

And since this is a second bite at the apple, it's got to hold up.

So, whatever OTA is required to get an image sharp enough to tell if it's tracking needs to be on there. And if that isn't Meade brand, then get ahold of whatever is needed. Evaluation of the ACF can be done separately.

The second item is point at some stuff along the equator requiring long integrations so tracking is obvious.

And yes, do both of these in the same image.

But trying to talk around doing sensitive evaluations or claiming hurt feelings isn't productive.

Because, at the end of all this, there isn't a third bite at the apple. And that's why I'm being critical.

-Rich
 

#73 galaxy_jason

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Posted 11 December 2012 - 05:06 PM

Accusations of falsifying data will get an emotional repsponse.

Last night was a little better seeing, not great, around 2" best focus. I also got a chance to try the latest firmware. This included some PEC updates and Starlock initialization updates.

Here is a 5.5 hour HA Rosette shot. The starlock tracking is essentially perfect. For the pixel peepers, you will see a very slight (about 1 pixel which is .77 arc seconds) diagonal elongation at the center of the frame. I believe this is the last bit of differential flexure. Not bad for a Cat.

Keep in mind this is an undprocessed image. Just combined then a slight stretch in PS. Many masterpieces you see on the net are deconvolved, dark overlay trailing reduced, etc.

http://galaxyphoto.c.../rosett_5.5.jpg
 

#74 n2dpsky

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Posted 11 December 2012 - 05:59 PM

I asked for comparison shots because it's very easy for people to be critical of others work when their's isn't subject the same sort of evaluation. I think some on the group are very interested in a positive discussion, but when others question the integrity of one of the foremost astrophotographers that I am aware of, I think that reveals their true intent, which is to bash Meade and anyone who works with them. Star hawk, are you even in the market for this scope? You're at a low latitude there in Tuscon. Can we see your Helix shot? I'd like to offer my opinion.
 

#75 andysea

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Posted 11 December 2012 - 06:20 PM

Great photos Jason!
What is the native PE and guided RMS of the mount?

Thanks
Andy
 






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