PHD Drift aligning

[Davey-T]

As the "clear sky" is pretty murky I thought I'd give the PHD drift aligning tool a go, I usually use a graduated illuminated reticle that works for me but thought this may be an alternative.

It says select the star in the appropriate place which I did but then when I click the drift button it automatically selects its own star which is fine but when I stop and adjust and start again it selects a different star, I thought I read somewhere that you can mark the star to see the movement after adjusting, not sure how this helps if it keeps choosing a different star,

With the trend line going upwards slightly the smallest adjustment sends it downwards, does this mean it's pretty well aligned already, seems impossible to get a straight line so how close should I aim for ?

Using SSAG 5.2 pixels 770mm focal length scope and entered settings into PHD2 so it can auto set itself.

What sort of PA errors should it report for good PA assuming perfection is out of the question

Dave

[Shelster1973]

Have only tried it in PHD2 and I could never seem to get it as a perfect flat line when aligning.

There is a tutorial for PHD2 that uses bookmarks as you mention so that you can see how far the star has moved..which is here...not sure how well that will translate over to PHD...but may be worth a read to see if it can be used

[Davey-T]

So now it's really annoying me, I pressed the button to slew and instead of going to the east it decided to go to the west, unfortunately west is behind houses so not a lot of good to me, 

anyone know how to force it to goe east ?

Glad I'm not wasting a good night

Using PHD2

Dave

That tutorial only seems to do AZ adjustment ?

[Shelster1973]

Sorry.  Can't help with the slew thing.

I issued all my slew commands via Stellarium...just had a Mk1 eyeball in the direction of sky that is clear and within the parameters it sets out for choosing stars and sent it on its way...

I need to revisit mine as need to modify the mount / pier securing interace.  I think at the moment there is room for it to move slightly and also need to put a large nylock on there to stop it coming loose when left for a while

[Davey-T]

Just spent four hours playing with PHD2 Drift align and think I've got the hang of it now, just a couple of things left to figure out 

Dave

[swag72]

I did the PHD2 drift align for the first time about a week ago. I am a self confessed numpty to be fair and following the guide here found it surprisingly easy. 

[Davey-T]

Thanks for the link Sara, I muddled my way through it, I don't think the mount adjustment is smooth or fine enough to achieve a straight trend line, also it insists on selecting extremely faint stars that aren't easily visible when there seem to be more suitable ones available, and if I let it slew on it's own it goes West, can't see a way to force it to go East.

Will have another go when it's murky again.

Dave

[Zakalwe]

It will try an pick a star that's not totally saturated- a blown-out star will make the calculation of the centroid harder.

Try reducing your exposure times to about 1 second- it's easier to see the changes on screen compared to a longer exposure time. Also try and get a star that's near the centre of the PHD guide window.  Also, make sure that you have calibrated first and that guiding is on and working.

I did see a tutorial that used bookmarks- to be honest it looked more complicated than it needed to be and personally, the bookmarks don't seem to work for me. The tutorial that Sara linked to is nice and simple.

[Davey-T]

I calibrated on an average star in the centre of the window but it chose  a really dim one right in the corner so I had to fiddle about moving into the centre then it promptly chose a different star in the corner 

Dave

[Phillyo]

Davey,

To slew east instead of west you just change the figures in the "slew to" box. Change it from -60 to 60 (or vice versa, can't remember which) and that'll force it to slew to the East instead of west  (if you can see that low).

I've never managed to get mine totally level either.

Phil