In true Homer style, I was mucking around with the AP1200 tonight trying to get better images of Stephen's Quartet.
Now, a bit of background. The AP1200 comes with PEM - programmable error management (PEC to you and me). This is programmed using either the keypad or a CCD imager. The CCD imager route is far more accurate so I didn;t bother with the handset routine. However, the DSI is not supported by CCDSoft and I'm not in a position to fork aout 3 or 4 hundred quid on MaximDL (which DOES support the DSI). So, needless to say, my mount is not currently calibrated for PEC...
There is another AP supplied utility, called pulseguide - once programmed, you center an object, let the mount track for 10 or more minutes and then recenter the object. With some deft software calculations and by sending pulses to the mount, the mount will then track that object almost perfectly. Great for asteroids or objects that move quickly. Also great if your polar alignment is a bit out. Its the same idea as autoguiding with an imager, almost. And provided by AP because object move at different rates depending on where you are pointing your 'scope.
Anyhow, the recommendation is that you do not use pulseguide without having your PEC recorded and programmed. So I've shied away from using it in the hope of getting a new CCD - real soon now.
Well, as I said at the start, I was mucking around and thought I'd give Pulseguide a go and hang the PEC advice.
Holy Mother of God... I spent 10 mins programming Pulseguide and then shot a 4 minute exposure (and you folks know my field of view....). PERFECT ROUND STARS. I was gobsmacked!
The Doh! moment came a few nanoseconds later - I could have been using this for the last x months... The problem I now have is that I need to shoot darks of greater than 2 minutes. Who knows what Pulseguide will do - 10 mins? 20 mins?
AP reckon with PEM (or PEC) and Pulseguide, you can go 30 minutes. I always thought this was a sales pitch. But now I know it isn't. Another Doh! moment. Believe everything AP tells you.
As I type, I have over 1200 seconds of Stephen's Quintet on the go and not a rugby-ball shaped star in sight. Can't wait to process it and let you folks share it!
Anthony, when you eventually get your new baby, you really are going to love it. With the AP160 attached, that will be a dream setup. BTW - sorry to hear of your SBIG woes. That's a real bummer. I nearly tore through the Dec cable on the AP1200 during an unsupervised (I was in the study) Meridian flip. I was gutted when I went out to the scope pointing at Terra Firma and the cable sheath all split - but luckily not seperated. A real sickener. I feel for you...
Cheers
Dave McD
  