yuklop

Thanks for your comments. I think deforking is pretty much a one way operation. Very hard to put back on well aligned, from what I understand. And yes, I can't justify the scope just sitting there doing nothing. Not sure whether the mount would take a 17kg OTA. Probably be OK for visual. It isn't a standard mount, but it is rather heavy and large, so it'd be interesting to see!

Thanks for the tip on the screws! I also learnt that a while back, but may well have relearned it this time too! 

And yes, it might be a hard sell to move on such a heavily modded item. I think its all to the good, Meade lx200 12'' with modern electronics, but people tend to prefer original examples I think. I do think it'd sell for enough for me to be able to replace it with a C9.25 OTA though. Not an Edge HD one mind! 

Today I am leaning towards the defork. It would be hard to get another 12'' SCT sorted if it turned out I missed it!

Appreciate the inputs,

Dan

Defork or not?

It is a tough one. It seems like a travesty to break up a perfectly good system, specifically this system: 

But I have moved to a GEM setup. So whilst it is great having the LX200 in alt-az for visual in theory, in practice it doesn't get used. And I would really like the chunk of garage space it uses up back. So options are to defork it, or sell it and replace it with a c9.25 ota or similar, which would fit on the GEM better. 

Would the aperture decrease make a practical difference? Would a C9.25 be noticeably sharper? If you had the choice between an lx200 12'' or a C9.25, which would you chose and why?

Dan

ps. I know this is a really nice problem to have . I have picked up the allen key to start the deforking, but I am just not sure I can bring myself to do it. Seems almost like vandalism!

Hi All,

I recently got my hands on the scope in the images. It’s a 8 inch dall Kirkham. It has no identifying marks at all as far as I can see. There is a little bit of paper with it that says it’s f6, but I think f16 is more likely.

found this: 

https://astromart.com/classifieds/astromart-classifieds/telescope-dall-kirkham/show/scientific-tinsley-8-dk-ota-sold-to-david

which suggests it’s a scientific tinsley?

What do you think?

Thanks very much!

To close the show, here are a couple of images of it installed on the pier working with the awr system.

Reckon that little es80apo is about the most overmounted scope in the uk right now 😁

Will have to learn how to sync that awr system and use it.

Well, here it is, reassembled and the AWR drives installed. I reckon I’ll probably attach it to the pier with the AWR system and give it a go. Onstep can come later.

How about one of the old version black HEQ5 mounts?

It is pretty heavy, so you future-proof a bit, and when one day a photo of a planet isn't enough it'll take most refractors for a decent deep-sky rig. If you put a bit of effort in (e.g. Onstep it) you get the full goto for very little additional cost, or just stump up for an upgrade kit, if and when, you are ready. You don't need the goto for planetary.

If you can find one of those, I think they are spectacular bang for buck. 

Its nice to hear of more such mounts still in the wild. By all means dump photos here, and don't worry about hijacking! If they are in the same place, it just makes it easier for future searchers.

Regarding AWR vs onstep. I have thought about keeping the AWR system and I may well set it up with the AWR first, since it'll take we a while to source and solder the onstep. There will be inherent backlash from the gearbox (although I have to say it is a very nice gearbox!), that onstep won't have and also, onstep is just so good. I have onstepped my LX200 mount, and really like how the system works, now I understand it all. And really, once you've onstepped once, it is a fairly simple conversion. 

I am just excited to get this mount installed, so main decision equipment-wise is whether to defork the Meade 12'' LX200 Classic, that is installed now, or not. I should, as its a lovely tube, but on the otherhand the whole onstepped LX200 works so very well, and was such a lot of work to get working that well, it seems a shame to defork it. I'm sure I can pickup another already deforked 12'' OTA at a decent price and keep the system I have whole for me or someone else in the future. 

Time will tell.

Wow, that is fantastic. What a wonderful design it is. I love all the metalwork and engineering on show with this mount - it is superb, and actually the reason I got it. I wonder how many are out there? Very interested to see photo's of any others that are around, and almost surprised that there are even bigger version out there. What was the design payload of the one in the photo, and was that not enough for almost anything already. It has a 24 inch counter weight arm!

And even though it looks fantastic, I do need to get it working and used too. It is destined for installation on my pier, to carry my 12'' lx200 if I can bring myself to de-fork it. I could also add my little refractors, but I think with the mount, more weight would help add some pressure to the RA axis and reduce slip. No idea if slipping is even a problem yet, but I am very much looking forward to finding out.

Hi David,

The AWR system is a micro stepper version. Image attached.

It even has some nice paperwork with it.

Hi All,

I have got my hands on the beauty shown below. I wonder if anyone has any more info or has seen anything like it? I have already done a gentle restore. Just changed the gaskets to cork, and given it a gentle shine. 

Interestingly, the RA axis is not held in at all, it is just the weight of the mount that holds it in place. The DEC has a block to stop it falling out.

From what I know about the mount: It was originally a Push-to design. It has been retro-fitted with an AWR drive system (not shown in images). I expect I'll change that out for an Onstep system, as its easier to interface that to a PC, and operates with a belt drive and not a gearbox. The AWR documents describe it as a "R. Miller early type", and this fits with the story as I have it so far, in that Rob Miller, of mount making fame, made it back in his Astro Promotions - Luton days, probably not as a production mount, more as an experiment. It is absolutely massive. The mount next to it is a HEQ5 for reference. The RA shaft is 2 inch stainless bar and a 7.5 inch brass worm gear. The whole head weights near 40kg.

I will try and use it for Goto and guiding, but it might be tricky with no axis locking or, even a way to tension the axis (like a Losmandy G11). Perhaps I'll have to try and retro fit some tensioner on the axis if it keeps moving in the breeze.

I'd love to learn more about this mount, and any thoughts on converting the old Push-to style to Goto.

Thanks,

Dan

Hi All,

I have an older mount I am restoring. On RA axis the slip clutch had 2 nylon gaskets, one either side of the work gear. On the Dec axis there is just the one gasket, and the other is a metal-metal surface. Does this sound normal, or do you think there is a gasket missing. 

Thanks,

Dan

I have a lx200 12'' classic that I have a real love/hate relationship with. It is fork mounted on a wedge on a pier, with a 80ed piggybacked.

When the seeing is good, it is great. But the seeing is so rarely good, especially in winter as I have to look over houses. The cooldown time is longer than most of my observing sessions, so tube currents are ever present. The mount is ok for imaging through the ed80, but not a lot of good for imaging through the LX200. The whole setup is so heavy and cumbersome I never get it out to darksky sites. And the thing that annoys me most... it is impossible to get decent balance with a fork on a wedge for all the sky.

I still love it though, because I spent quite a bit of time with it and changed out the old Meade electronics and drives for an onstep system that work superbly, so it is a custom effort.

Even with all that I am thinking of moving it on and using the 80ed on a GEM for imaging and getting a 8'' or 12'' dob for visual. Reckon that would be an easier and more rewarding setup, that I might be able to drag out of the light pollution once in a while.

Anyone else been through this kind of change, and what was the outcome for you?

A couple of composite images from last night. Was a nice observing session last night. Seeing good enough, not too cold and rather enjoyable.

Oh yes, I am sure they could be improved drastically. My skills are weak for planetary and none of these are great shots, even for me. It was the comparison of the scopes I had fun doing here, that I wanted to share.

I should work more on planetary. For some reason it never comes out quite as well as I think it should. I think there is a lot of skill involved, and the requirement for favourable conditions.

A little while back I was lucky enough to get 3 scopes setup in the back garden on the same night. So here is a Jupiter through all three! 

Don't read too much into it, they were all done on the quick a bit, so focus is likely as not the deciding factor. The image scale is interesting though as a direct comparison. All shot with an ASI224MC, 30s vid, and straight out of autostakkert, top 10% of frames. No further processing.

The ACF makes a more yellowier image than the classic. The little MAK was a pleasure to use. 

FYI: The MAK was on a skywatcher skymax, the Meade ACF was on a Celestron CGEM on tripod, and the Classic was pier mounted on its LX200 mount.

I think you were all spot on. I observed the feature last night and it does look like an air current. It does reverse side as you move through focus.

It was still very visible after 1 hour outside and the night wasn't that cold, although I suppose the difference in day temp to night temp was rather high last night.

Still, it was partially cloudy, seeing was awful, and it made a perfect chance to muck around with watching and learning about heat currents inside the tube. Oh, and of course fiddle with the collimation, which I am never sure I have quite as good as it could be! A pointless exercise when the seeing is like last night though!

I find this 12'' SCT, when its good its very good, but I have only seen that one summer night in the past couple of years. Unfortunately, in the winter (and last night), since I must look over houses, seeing is always poor, and this scope really enhances any bad seeing effects!  

It could well be. Scope is permanently mounted in an obsy, so I thought I’d be fairly immune to that. But perhaps not. It might just be clear tonight, so I’ll check it out! Thanks for the idea.

Hi All,

Has anyone seen this before. In the out of focus star pattern on my Lx200 classic, there is an area that is dark, almost like there is an obstruction in the light path somewhere.

I have since collimated a bit better, and checked there is no obstruction and made doubly sure there are no reflecting surfaces inside the tube (screw ends etc).

It now looks similar but less extreme, like an arrowhead pointing into the pattern.

Any ideas from the experts?

Thanks very much.

Finally a wonderful nights observing.

Didn't start that way, as with the good news that COVID is in decline has meant a rise in aircraft. So my skies looked like this at the start of the evening, and the moon reflecting of those con-trails meant I was in a poor mood. See image below. I like the geese though, who photobombed my image of con-trails. In fact I was so grumpy I very almost didn't bother getting the scope out, and was going to post a rant on con-trails instead. Glad I did though as eventually those trails melted away and I got some excellent views of Jupiter and Saturn. I was using a Meade LX200 Classic 12''. Recently got the collimation really sorted by following this advice: Collimation of an SCT from scratch, a photo guide - Major & Minor Planetary Imaging - Cloudy Nights. Previously collimated to get a centred ring in the donut, but this time focussed it down to get better and better. It worked too, as the good collimation, coupled with the really still atmosphere last night gave the best vies of Jupiter and Saturn I have ever had. I managed to get the power up to 435x, with the 7mm eyepiece. I have only every managed to get down to the 12mm previously, before the view washed away to blur. Cassini division was easy. Jupiter was superb, watching Callisto emerge from behind the planet around 22:00.

I am very poor at processing planetary images, mostly because I have rarely had data worth processing, but I gave these a go. Attached here, is a Jupiter and a composite of Saturn and its moons. Obviously, the moons were taken at a very different exposure to the planet and the images combined later.

I hope many of you also got great views of the two heavy weights.

Like many on here I am a keen watcher of ABS. There are so many lx200 classics or gps on there right now. None are selling.

I got my lx200 12’’ classic for £500 a few years back. Most are up for 3x that at least now. Might explain why they aren’t selling I suppose. But what are they worth?
 

I’d say a 12’’ classic or gps is worth about £1k if in good nick. The acf’s perhaps double that. What do you think?

10’’ maybe £750

8’’ perhaps £500

anyone care to value the 14’s or 16’s!? These are a bit harder. 14, say £2k and 16” say £3k? Reckon I’d pay that if I had it!!

look forward to your opinions,

Dan

Hi Schism,

Have a look at onstep. 
Here is my lx200 which also had dicky drives fixed up with modern motors and electronics.

Hi Davey and Michael,

Michael, I don't think it matters whether I start horizontal or vertical. I can get perfect balance in DEC quite easily. But then RA balance is way out and it wants to re-centre. So its not a case of one RA arm being heavier than the other.

Davey, does your scope with the 4'' frac on the back balance well for all areas of the sky... i.e. could you point it anywhere and let go and have it stay there if you hadn't made it deliberately front heavy?

Hi Dave,

I tried that too. Made my own 3d balance system where I could offset the counter weight. Didn't help me. What I could do with that is use it to balance at any specific RA. But not for all RA. So with the DEC perfectly balance the RA balance shifts depending on where the scope is pointing and would need to be rebalanced for every RA. This is a pest, so I went with the compromise balance option.

As an update to this, after a load of mucking around I learned that I can balance perfect in Dec or in RA but not in both.

I can move the counter weights far forward on the rail and the RA balance is perfect. Problem is then the scope is very front heavy. Attempts to correct this, either with extra weight or moving the guidescope back ruin the RA balance again.

At the moment I have a compromise setup with the Dec balanced OK at the most common observing declinations and the RA balance pretty good. Still has a tendency to want to return to forks level, but not so much I am worried about the motors.

I am still stumped as all the guides and even books just say, point tube up and add correct counter weight, point tube level and move that weight forward to back. This is perfect dec balance. Then simply add a little weight to the light fork arm. Then you have perfect balance.

Which you don't. I am beginning to think it may not be possible to achieve the fabled perfect balance with a wedge mounted fork and some accessories added. Has anyone done it?

Could also try Onstep if you are up for a bit of a project. 

https://onstep.groups.io/g/main

Can be done very inexpensively. You will need to be able to hack together a mounting plate and be a bit handy with computers.. The instructions are very helpful, but it will not be plug and play. I just finished converting an LX200 classic to Onstep and it went pretty smoothly and I do not have any specialist skills.

Might do my old black HEQ5 next, which would be a very similar project to yours. Quite a few folks have done an EQ3 already, so you won't be breaking new ground: https://onstep.groups.io/g/main/wiki/4414 (about a1/3 of the way down the page)