Possible improvements to NEQ6 mounting on pier and PA adjustments.

[Gina]

I've put everything back in the obsy and on the pier. I can report that the altitude adjustment is now easy and smooth - a vast improvement Forecast for tonight is for clear sky so I plan to PA using AstroTortilla and then continue to capture data for the Crescent Nebula in Cygnus

[Astrokev]

Humped the mount back into the obsy this morning but nut yet onto the pier.

I've been looking at the geometry of the altitude PA adjustment. At a guess I would say the distance from axis of adjuster bolt to axis of pivot bolt is about 40mm. Thread pitch is 1.5mm so 360 degrees of adjuster is 1.5mm at 40mm. So the altitude angle A is given by tan A = 1.5/40 = 0.0375. That's just over 2 degrees. So each degree of altitude corresponds to about 180 degrees turn of the adjuster screw. So we now have a much better idea of how much to turn the adjuster than just try-it-and-see

Assuming the geometry of the adjustment bolt is at right angles to the axis, the trig looks reasonably sound. That's a huge angular movement for a relatively small adjustment on the bolt. With such gross adjustment (when one also considers the crudeness of the bolt threads, the ends of the bolts and the surface it's acting against) attaining high precision in PA will inevitably require a fair bit of trial and error!

[Gina]

Assuming the geometry of the adjustment bolt is at right angles to the axis, the trig looks reasonably sound. That's a huge angular movement for a relatively small adjustment on the bolt. With such gross adjustment (when one also considers the crudeness of the bolt threads, the ends of the bolts and the surface it's acting against) attaining high precision in PA will inevitably require a fair bit of trial and error!

Yes indeed, very much so! That's really why I was looking for a fine adjustment method. I would consider this as coarse.

[Astrokev]

Yes indeed, very much so! That's really why I was looking for a fine adjustment method. I would consider this as coarse.

Another option (which I think may have mentioned in an earlier post but I can't be bothered to go back and check....it's been a long day at the mill....) cold be to do course adjustment with the EQ6 adjustment bolt, and then fine adjust using your pier head adapter plate. The distance between the bolts is greater than 40mm and therefore may give higher adjustment precision. Having said this, the thread pitch is also bigger which may cancel out this benefit.

[fwm891]

I have thought about fixing the mount to a mounting ring that is not horizontal. For example, if the mounting ring were inclined at thirty degrees towards the north then the mount would only need to be in the position it would normally have for about twenty degrees latitude (for you and me, at least). The rear alt adjustment bolt would then bear on the adjustment cam much more squarely, reducing the sideways load on the bolt and making it easier to turn.

James

With James on that. providing the RA axle is polar aligned it doesn't matter what angle the base plate sits at...

[Gina]

Another option (which I think may have mentioned in an earlier post but I can't be bothered to go back and check....it's been a long day at the mill....) cold be to do course adjustment with the EQ6 adjustment bolt, and then fine adjust using your pier head adapter plate. The distance between the bolts is greater than 40mm and therefore may give higher adjustment precision. Having said this, the thread pitch is also bigger which may cancel out this benefit.

Yes, I thought of this myself. Also, the azimuth could have a similar fine adjustment - move the plate sideways slightly.

I tried to get AT working to PA tonight but couldn't. Been having all sorts of finger trouble Anyway, I gave up on PA and went for imaging the Crescent Nebula in Cygnus. Doing that now and moved up to 10m Ha and 20m OIII subs. Guiding with OAG, Lodestar and PHD is working well using 0.5s integration time.

[Gina]

Just tried AT to solve one of the PA image filees from last nifght and it solved it, no bother, in 43 seconds. Now why wouldn't it work last night ?! I wonder if it was because other software was running. Guess I should try it with everything else running during daytime. I doesn't matter if Artemis hasn't got stars to look at - I cab use last night's images. Juat won't be able to do a slew and get the new image to check PA. But the problem was that it simply wouldn't solve.

Back soon...

[Gina]

Ran CdC, connected to mount, pointed scope east, ran Artemis Capture, ran AstroTortilla and tried solving a capture file from last night - solved in around 80s. Connected AT to mount and ran the PA part, selected same file - wouldn't solve! Task Manager reported EQMOD not responding.

[Gina]

Running AT without CdC running solved the file but took 200s. Seems I might be trying to get too much out of my llittle netbook.

[Gina]

Running the PA utility in AT and trying to solve the same file didn't work.

I have one more application running during this process and that's TeamViewer. To check if this is causing any problems I'll need to run my tests in the obsy rather than using TeamViewer to control the netbook remotely.

[JamesF]

Could it perhaps be down to lack of memory?

James

[Tinker1947]

Time for a upgrade Gina,,,,people on here are very adapt at spending other peoples money so i will set the ball rolling with this,,,,,,

http://www.morgancomputers.co.uk/product_detail/14097/Asus-A54C-Intel-Core-i3-2-2GHz-15-6-LED-Screen-4GB-DDR3-RAM-500GB-HDD-Win-7/

[Gina]

Could well be - it's only got 1GB. It gets very slow at times and sometimes fails to update the screen. I think I could do with something better.

[Gina]

Time for a upgrade Gina,,,,people on here are very adapt at spending other peoples money so i will set the ball rolling with this,,,,,,

http://www.morgancom...00GB-HDD-Win-7/

Thank you Cross posted That looks pretty reasonable - I've bought computers from Morgans quite a lot - in fact most of my PCs are from them. I don't need a laptop as I have plenty of room for a desktop in the warm room. In fact I'm already storing 3 in there. They aren't any good for imaging as they're all of lower spec than the netbook.

This one is about fifty quid more than that laptop with a higher spec (though an adequate spec is all that's required really) :- http://www.amazon.co.uk/gp/product/B006ZINMP6/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A3P5ROKL5A1OLE

[Gina]

Actually, thinking about it, a laptop might be of benefit. When testing kit indoors I can easily bring a laptop indoors to run the tests with the exact same software. I've done that at times with the netbook. That desktop I quoted is definitely overkill for an imaging computer and I wouldn't be using it's power/capabilities. (And fifty quid is fifty quid )

[JamesF]

Morgans were doing some very cheap deals on a few laptops earlier this week. I was half-tempted myself and I don't really even need one

James

[Gina]

I've ordered that Asus laptop from Morgans - couldn't see anything better for my purpose

By cutting running software to the very minimum I got AT to help me with my PA and got both axes within 2moa. I think that's just about as good as I could get it by "breathing" on the adjusters. Any better PA will need a finer adjustment. Anyway, I'm running 10m Ha and 20m OIII subs on the Crescent and the guiding looks pretty goof using half second integration time.

[Singlin]

When I dismantled my old EQ6 the steel washer was missing, is this normal for the old eq6?

[laser_jock99]

Thank you both

I've been Googling and browsing other threads on here and pretty much have the gen now

This is the thread that describes the metal wedge attached to the lever/lug :- http://stargazerslounge.com/topic/164290-neq6-tight-latitude-adjustment/

And a more refined engineering solution :- http://stargazerslounge.com/topic/161907-neq6-tuning-kit/#entry1635804

But a simpler solution without using any additionat bits of metal that would be very quick and quite adequate I think for a pier mounted mount ( ) which is only going to be set once and left :-

http://www.alphageek.co.uk/page21.html

Swedish SGL'er Gunnar made some extra latitude adjuster plates- if contact him directly he will sell you one. Choice of colours too!