Mount levelling

[ollypenrice]

The best mount to align, and by a country mile, is the Takahashi. Mine's the EM200. You can be polar aligned for long sub astro imaging in around two minutes.

So unimportant is levelling that Tak do not even put adjusters on the legs of the tripod. If you're on a slope, so is the mount.

The bubble level is where it should be, on the RA housing. Its main role is to calibrate the offset of Polaris on the polarscope reticle - which is all it is doing on normal EQs as well. There is a time zone offset to calibrate the Bubble Level to your time zone.

The case for levelling says that interaction between RA and Dec misalinment is reduced -and this is true - but if the mount is something like level then the effect is miniscule.

I doubt that Tak can have patented their system so others really need to wake up and join the club.

On piers, yes it strikes me as bonkers to build a pier in concrete then perch the mount on top of some wiggly bolts for no reason at all, fork mounts excepted.

Olly

[Marmite]

Ha!

A mate in the city invited me round to see his new baby, so off I went expecting to discover a big shiny green and white thing with Japanese writing on it.

But no, he had built himself a new pier in his back yard.

You could tether an aircraft carrier to the thing, but obviously he had looked at way too many pics online, and topped it off with a ratbox.

So I showed him that video.

He glared at me for a minute or so then stomped off towards his garage, swearing away.

A moment later he reappeared, dragging his angle grinder and welding kit!

:)

[Starlight 1]

For anyone that may be thinking of drilling an "access hole" after you put the hole in fill the pier with sand so if you drop anything in the hole it will not go all the down,Well the best thing you can put in any pier is lead shot.

[libraryman]

Just shows how good this forum is, just as i'm about to make my own pier!

257mm dia pipe 6mm wall 1 mtr high, a reasonable 8mm thick base at 350mm square and i was pondering how to engineer my leveling options now i dont have to.

The concrete base; i still think 1 square mtr is overkill i hoped to get away with 2'x2'x2', maybe i'll just increase the 1st 6" too 3'x3'

I noticed that the scope and sky piers are 6' pipe or less, perhaps thats why they need the extra bracing struts.

Anyone care to comment on whether i should add braces before i weld it up? i dont want them if i dont need them, the pier will also be buried in sand 300mm.

Ray

Ray

[Starlight 1]

Well I allways said fill a bit of pipe with water when its at top of the two ends its level.

I would put a sand pit all the way round the pier a good 4ft out as well.

[cgarry]

Anyone care to comment on whether i should add braces before i weld it up? i dont want them if i dont need them, the pier will also be buried in sand 300mm.

Ray

Ray

I would definitely recommend adding braces. My pier does not have them and it does like to wobble for quite a few seconds each time I bump it. I filled it with sand but that just made the vibrations go at a lower frequency.

Chris

[libraryman]

If you watch the video in this thread i see some sales chat mixed along with good advise, the braces are substantial top to bottom but on my pier they would add considerable weight, not that it matters when in place but i still have to maul it around to get it there.

There is the good pier design thread on cloudy nights that discusses pier dia as the most important factor, it does not talk of extra braces and the jury still seems to be out on the issue unlesss smaller dia tubes are used, as in the S&Skies design.

Ray

[Geordie mc]

I too have always faffed about trying to level the tripod before adding the head and aligning. I thought that it could cause field rotation when imaging if I didn't. I take it this is incorrect and I can save myself a few minutes and leave the mount fully assembled? Thanks everyone.

[Stevp]

An old topic,I wish I'd seen it a year ago!