Meade LS8 - more inches for the aperture afflicted.
| 3 Comments... |Meade LS8 - Addendum to the Meade LS-6 review published earlier
As readers of my original Meade LS6 review may recall, I was quite impressed with Meade’s LS6 ‘autoscope’, albeit with a few caveats with regards to the tripod and accessories – but overall, good marks. The 6 & 8in scopes differ only in the OTA’s and weights thereof, so I’ll confine this review to the differences between the two, rather than duplicate the report on everything else. I would suggest that interested readers look up my review of the LS6 elsewhere on this same site.
I even said in that first review that the LS6 was probably a ‘keeper’. Well, I should have known I was fooling myself. I ultimately wanted more aperture than 6in, but didn’t want to give up the hedonistic auto setup that the LS series provides. So what to do, what to do?…….mmmm. Well, the obvious answer was to buy an LS8.
So, after watching the various sites for a while, a good deal came up on one ‘relatively’ close to home. (I think astronomers must compare driving distances relative to light years – because it was still a 6 hour drive in total) It also had the most current firmware (v1.6a) that apparently made my LS-6 such a trouble free performer. So cash in hand, I trekked out to pick up the LS6s big brother.
And bigger it is. Where I originally commented on the beefy size of the mount relative to the 6in OTA riding on it, the mount looks comparatively overwhelmed swinging the 8in OTA . The 8in ACF tube takes up all the gaps that the 6” enjoyed on the sides and bottom.(there should be ‘Pinch’ warning labels on the mount…) With the same Eclips CCD and LNT (Level-North Technology) modules mounted on the OTA, it is a physically large looking setup.
And I don’t know how Meade did it, but the LS8 does indeed weigh only 2lbs more than the LS6 – coming in at 32lbs.
The tripod is the same for both the 6 & 8in and weighs 9lbs, so all in all, both are still both very portable set-ups..
One of the things I really like about the LS series is the completely automatic setup. I’ve paid my dues over the years and I have the grass stained knees and kinks in my back and neck to prove it, so with the LS performing all the preliminary alignment and setups automatically – it’s a pleasure to just walk up to the scope and start observing. You literally just plunk the tripod down hapharzdly with only cursory attention to being level and the LS modules and firmware figure it all out from there. As I mentioned in my first review, the LS firmware also looks after some of the ‘housekeeping’ like gear backlash and the GPS and LNT modules look after everything else.
However, when I first fired it up, the Alt Axis was screaming like a banshee. I had remarked on the LS-6 being quite quiet when slewing. This was definitely a ‘wake the neighbours’ issue, and it didn’t sound right. So never being someone to pass up the opportunity to take something apart, I took it down to my shop, pulled the fork cover off it to see what was going one, and found that at some point in it’s life, it must have suffered some sort of catastrophic ‘crash’ incident. That incident had been forceful enough to break the flange off the inboard worm shaft bearing and push the remaining bearing body deep into the bearing housing, allowing the opposite outboard end to pop out of its bearing and just flop around unsupported. The poor motor and gears were screaming in protest trying to overcome the additional loads imposed by this gross misalignment. Fortunately, a $5 - 5x10mm flanged bearing from the local RC hobby store has restored peace and quiet. I had contacted Meade service to see if they could supply this part but never heard back from them….. If anyone is interested in getting some pics of the LS guts, I’d be happy to email them to you.
Once this was overcome, I then discovered that someone had monkeyed with the focus set point of the CCD camera lens and the CCD was apparently unable to recognize the washed out and bloated out-of-focus star images, and so was not able to automatically align as a result. So some judicial pointing and CCD previewing of an artificial star on the remote Meade LCD screen enabled me to thread the CCD lens housing in-out to achieve the proper focus.
Once all this was done, something then hiccupped in the firmware, and the scope started doing strange things. When I tried to refresh the firmware from the Meade ASU (Meade’s updater program), it completely killed the scope and then nothing worked, and the ASU would not even acknowledge the scope’s presence at the other end of the USB cable…
So there was a considerable delay while I located a miniSD card (not SD or MicroSD – but miniSD – half way between an SD and a microSD and only produced for a short period before the Micro took over). Once the ‘boot’ card was created from the Meade ASU, this was plugged into the scope, powered on and it uploaded v1.6a to the scope. (BTW a 512MG capacity card will work. They were available up to 2Gig)
About half an hour later, holding my breath, I cycled the power, and Voila!....I once again had a workable scope. This points out the hazard of today’s full electronic scopes. If something does go wrong …you’re dead, and in the case of the LS series, the OTA’s are not (easily) removable to use on another mount, nor are they usable manually like the old LX200’s..
I also had a ‘bobble’ when the LS8 refused to get a GPS lock in the same location as my LS6 did. However, when I moved a little further into the back yard, the LS-8 mount performed the setup chores as my first LS6. However, the GOTO accuracy did not seem to be as good as the LS6 and it was more sensitive to GPS ‘shadow’..
The GOTO’s seemed to put the target in the outer 1/3 FOV of my 19mm Panoptic (108X). While I was silently grousing to myself that this wasn’t as good as my previous LS6, it occurred to me that the same 19mm Panoptic in the 2000mm LS8 produces a FOV that is 33% smaller, so what may have been just slightly off center in the LS6 (and considered very good), would be in the outer 1/3 FOV of the LS8 – so all in all, I guess still pretty good. So using a longer focal length eyepiece with a wider FOV would be recommended for initial target acquisition.
The good news through all these trials and tribulations is that because the scope was likely not performing for the previous owner, it didn’t see much use, so everything was essentially new.
One of my main concerns with the LS6 was that I felt the factory tripod to be marginal even with a 6in OTA. Not only is the LS8 heavier, but its moment arms are longer, thus magnifying any vibration inputs (like focusing) more so than on the 6” model. The fact that my used LS8 came with a Meade Electronic micro-focuser said something in itself…
I had read online reviews regarding the LS8 using the factory tripod, and no matter how those reviewers pussy- footed around the issue, vibration was apparently an issue. As anticipated, it was difficult to fine focus the LS8 using the factory setup due to excessive vibration. Using the straw poll eyepiece tap test, the vibrations took several seconds to die down. Conventional wisdom says anything more than 2s is undesirable. I never thought to do this test on the LS6 as focusing was never a chore, but with the LS8, it is.
The focuser on the LS8, like that of the LS6 before it, was very stiff – and this contributed to excessive vibration while focusing. After dis-assembling the focus mechanism, cleaning out the viscous silicon grease they use, and re-lubing with a good Moly grease, the focus action is better, and this in turn results in less transmitted vibration when focusing. A further upgrade using the Peterson Easy-Focus kit reduced the vibration even more. Focusing has improved from ‘frustrating’ to ‘tolerable’.
Meade should know better. They ship their 8in LX200’s with rock solid field tripods – I know, I’ve had several. This LS8 ACF has exactly the same optical tube that you would find on their 8in LX200-ACF, plus the additional weight imposed by the Eclips CCD and LNT modules PLUS the handicap imposed by a single arm mount, yet they still put it on a flimsy tripod. I don’t get it.
I was very impressed with the 6in ACF optics, so I had high hopes for the ACF-8in version. An 8in primary gathers 77% more light than a 6in and this was immediately obvious in the brighter images and increased resolution. Things just ‘pop’ more in an 8in, and dim smudges take on a more interesting aspect. The 8in ACF optics were just as good as the 6in version with all the added advantages of light gathering and resolution that comes with the larger aperture. The 8in ACF optics produced very satisfying images.
This LS8 came with the optional 3.5in LCD screen which will allow you to play the multi-media videos built into the LS series, but also allow you to see the view thru the Eclips CCD finder, and take still pictures which can be saved to the built-in SD card. (Note: you cannot take pictures thru the main optics with the Eclips CCD camera). I had always rolled my eyes at this option, and had never explored it with my LS6 even though I could have output to any standard NTSC compatible monitor.
Images can be captured thru the scope’s Eclips CCD camera and saved to the SD card. However they are only VGA 640x480, so they’re pretty grainy. (Are you old enough to remember that resolution?) But if you want some foolproof way to ease into astrophotography, it will deliver wide FOV pics of your favourite constellations and brighter sky objects. It’s also pretty neat to show people new to the hobby, a naked eye view, a low magnification view thru the CCD and finally a higher magnification view thru the eyepiece. Sort of stepping into it by degrees, and certainly gives them a sense of perspective.
It is also handy for showing much more options on one screen when navigating the menu. And it’s sort of neat to watch the automatic star align process as the CCD camera takes an image, lays crosshairs over the FOV, locates the star and then compensates to bring it dead center.. And without that screen, finding the focus of the Eclips CCD camera would have been a lot more difficult.
It is however quite bright, even in night mode, and you’ll want to toggle it off with the Disp (9) button when viewing as it is right there in your peripheral vision otherwise…
Wrapping it up.
Not much to tell. After I worked thru its issues (none the fault of Meade), the LS8 was every as good on the auto-setup and GOTO’s as the 6in.
The tripod is worse thanks to the added weight and moment arms and the accessories are the same.
The 8in ACF optics deliver great images with brighter and higher resolution views that its additional aperture confers.
Just get rid of the factory tripod and re-grease the focuser, and you’ll have a great scope.
I ended up selling the above scope, but as is often the case, had regrets, and bought another one a year later. This one had no issues, and the final comments above, also apply to this one.
However, there are three improvements that I made on this scope that make it a lot easier to live with – almost pleasurable.
1. I found a Meade Std field tripod (they come with the LX200 or LX90’s) and I just re-drilled three holes in the top to match the LS bolt pattern (3 on 4”), and removed the central LX200 hold down bolt. It is a much more solid tripod and this translates into less vibration.
2. I installed one of the Peterson focus kits, which results in lighter, smoother focusing action. This and the tripod drastically reduced the vibration when focusing – but not entirely……soooooo
3. I figured the biggest handicap the LS8 faced was its single arm design. That 8in ACF OTA is quite a moment arm hanging off to one side, and the focuser is on the opposite side, so even the lightest touch gets magnified into annoying vibration in the eyepiece. So I wondered what would the LS8 be like if it was a dual fork design…
Enter VARM (Vibration Attenuation Arm by Malcolm….sorry…) This is an auxiliary fork that I devised that clamps to the lower end of the LS mount, and bears against the outboard side of the OTA at its central pivot point. This has the effect of steadying the opposite side of the OTA and damping out and/or preventing oscillations. No mods to the OTA are required and it was the final solution to the vexing focus vibration problem.
I can’t figure how to post pics embedded in the article so if you’d like to see some pics, drop me line and I can send them to you separately.
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