Polar alignment stuff

[namreg]

Hi guys

Quickie on polar alignment (work of the devil) and more specifically getting the polar scope reticule aligned with the mount (EQ5 in my case). I've tried polar aligning without doing this, and it doesn't work (for imaging)!

I'm following these excellent instructions:

Astro Babys HEQ5 Polar Alignment

and it mentions that when aligning the reticule it is best to do it indoors and set the mount to zero elevation. My mount won't go anywhere near zero elevation. Best I can get is around 20 degrees.

Is that normal, or is my mount playing silly buggers?

Doug

[Dave-Ryan]

I don't think it matters about it being zero elevation it's just easier to adjust the reticule when it is.

Not sure about the mount, I have the HEQ5 pro not the EQ5.

[namreg]

Does yours go to zero elevation Dave?

[Dave-Ryan]

It does yes.

[namreg]

Maybe it's just a difference in the mounts then. That tutorial is written for the HEQ5. I didn't realise they would be different to that extent.

Cheers Dave

[Dave-Ryan]

I'm sure somebody soon, that owns a EQ5, will put you right on that. Sorry I can't help any furthur.

[dmahon]

If you set up your mount so that the centre of the polar scope is pointing at a fixed point (I used a bit of paper stuck to a wall with a dot drawn on it) and then spin the RA axis through 180 degrees, it should stay centred if properly aligned. I was lucky - mine was aligned perfectly from the factory. If yours is, you can skip "aligning the reticule" and go straight to the next page.

It's easier to use bits of paper stuck on walls if you can get down to zero degrees elevation - otherwise you'll have to pick something else to use as a target (like Polaris - or any other star - and do it in the dark).

[iamjulian]

I have the EQ5 and I didn't take it to zero degrees, didn't need to. I just put a postit note with a dot in the middle, on the door at the top of the stairs. Then do your alignment from the bottom of the stairs.

[namreg]

Thanks guys. I tried that initially but found I was having difficulty focussing the polar scope that close in. I'll give it another go. The bottom of the stairs sounds like a good idea!

[mark7331]

As has been said it doesn't need to be horizontal but the more distant an object the better - a street lamp will do. I do check against polaris though once I've done the "daylight" check.

Also i've found that using a collimation cap over the polar scope "eyepiece" improves the alignment accuracy by reducing the angle at which you look through the scope. It becomes obvious then if the target moves at all.

Hope it helps.