Web Cam Autoguiding??

[krobbo]

Hello again my friends!

So slowly getting all the gear to talk to each other but having a doozy of a problem getting a creative live webcam to act as a autoguider!

IR filter is out & 1.25 tube affixed. Mount is trying to track but I can't get a starpoint image! Focus travel is fine will go past critical focus point both sides of focus but all I get is a blob of  star. Using PHD2 with all ASCOM drivers & Shoestring interface. Celestron Celestar C8 Deluxe with EQ wedge, field flattener, webcam mounted directly onto rear cell. Still trying to get my head around the software, could it do with pixel size setting?? Using the reticle setting, can see it trying to track but it drifts off after approx 20 seconds?

Should I just give up with it & get a QHY5L (budget allows the Colour would like to use it for planetary, sensitive enough for an OAG??).

Would like to start imaging at some point !!!!

Cheers again for your grey matter help!

[Freddie]

Unless it's a massive "blob" it shouldn't make much difference as PHD calculates the position of the central point. I assume you have got PHD to calibrate but it drifts when it starts to guide? If it has calibrated, then there isn't a problem wit the cam.

[michael8554]

The guidecam display of stars  on PHD2 tends to look like blobs, more important is the Star Profile - this should be a fairly sharp "mountain", though some say a slightly flat top is an advantage.

As Freddie says, if it has reported Alignment Successful, then all is well, you will then have to set Agr high enough, and exposure fast enough, to keep the scope guided.

You are asking a lot using the C8 as the guidecam.

Michael

[newbie alert]

Is that right that you're using the webcam throu the c8?

It be hard pushed to do that,I think you want a 60mm guidescope or finderguider..c8 has a fl of 2003mm..you need something around the 300mm Mark.. 

Must of read that wrong as what are you imaging with?

[krobbo]

Hi guys. The C8 is going to be the main imaging scope. I wanted to see if the webcam would track & thought initially as a test I'd try it through the C8? That might be where I'm going wrong. I've a focal reducer on it as well down to f6.3.

I've a OVL OAG but was also considering using the 50mm finder scope as  the guide scope? I've modified the rings on it so as to eliminate the front rubber mounting ring & its flexure & has a full set of alignment screws on it now.

I'm trying to do it step by step moving through the gear until it all gels together.

How do I calibrate PHD? That looks like a step I've missed !