Odd tracking...

[eddy]

Hey guys, im not autoguiding yet so purely my tracking is all based on PA.

At the moment my subs are 60secs max as thats all i can manage without trails, 3 out of 5 subs are good, the other 2 show trailing, not much, couple of pixels....

Now is this bad PA or bad PEC? I know i dont have PEC on the motor drives, so pressume it could be this? Or is just the limits of the mount/motors?

EQ5 + Motor drives btw

Any advice welcomed!

Thanks

[lukebl]

Without guiding, 60 secs is pretty good actually! If you want longer exposures you have to start autoguiding.

[Shibby]

Could be either - if it's PE it will show up in the W/E direction. Poor PA is more likely to show up as an error in the N/S direction (I think?)

PEC is not something I've tried but I understand you can do it with EQMOD by recording a few full cycles of the gears with a webcam.

[eddy]

Ahh ok cool, i did have a 'tweak' toward the end of the session and try and get rid of the drifting but, no luck to be fair! LOL i think next time, ill spend a bit more time getting my PA right, it doesnt help that my polar scope is a little off anyway, that could be 1/2 the problem, i can manage 60sec subs, but would like to get upto 90sec if possible!

[Spikey]

Is PEC worth doing without being in a fixed observatory? Probably not.

60 seconds isa pretty good, you could get longer by refining your PA and drift aligning.

Or forget about all that faff and go autoguiding instead

Finder guider/SPC900 would work well on the ED80. I bet Quatermass has it working as he has an almost identical setup to you. Drop him a PM and see how he's put it all together.

[The Viper]

90 seconds is possible,thats the maximum i can get with my EQ5 and dual motors.Thats a 1m focal lenght on the 200p.Obviously PA needs to be spot on,or better drift align the scope and 90 second subs is a real possibility.Good luck

[eddy]

Thanks all for the comments and replies!

As far as drift alignment goes, i dont have a reticule of any sorts. Could i do this without a reticule? If so, any guidelines?

My PA is a little off, obviously, but i can get 60secs straight off, so its just a case of fine tuning for a bit i think. Ive got £150 to play with at the moment, now i know this isnt anywhere near enough to get me guiding, but where would i start? LOL Whats the most important thing for guiding? Scope? Camera? Mounts?

I was looking @ either:

Orion 50mm Guidescope

OR

SW 9x50 finder

Thanks again!

[Spikey]

9x50 guider = £30-40 ?

SPC900 £30 unless you already have one.

Finder guider adapter = £30

PHD software = free

£100 and you are basic autoguiding.

[eddy]

+ £60 for USB guider interface

£160 basic autoguiding

I have a 50mm guidescope on the way now, and my eyes are peeled for a suitable webcam to use, so if anyone sees one, or can suggest 1 i can go out an buy that would be great!

Thanks for the replies!

[Spikey]

Can't you use EQMOD and pulse guide?

[eddy]

Isnt EQMOD just for mounts with synscan?

[Spikey]

Yeh that's true, my mistake.