Guiding

[Gavin1234]

Hi guys. I’ve had my autoguiding gear for a week or two now and I don’t seem to be having issue with it. In fact it’s one thing I can say so far that seemed fairly easy.

I just thought I’d check that I’m doing it right. The attached are pictures of my graph and my numbers. Do these look OK to everyone? Are the numbers acceptable or should I make some changes. They’ve been roughly the same every night but this is about as low as I can get them.

Still haven’t done any darks for phd2 yet.

[Capella_Ben (Ben)]

I can't see all of the settings in phd2, but that looks about right.

You might want to change the scale a bit on the y axis. That scale makes it look better than it really is.

Are your subs coming out alright? round stars?

[Gavin1234]

Yeah subs look ok as far as guiding/tracking goes. Can you tell if its working well from the numbers?

[Cimitar (Evan)]

Hi Gavin, I also like to use the Star Target display as it shows me how much the star is jumping around and helps me narrow down any issues.

Another suggestion is to try changing your graph so it displays Arc-seconds instead of pixels (px). Depends on what format you like though. I think you can change it via the settings button above the RMS error values to the left of your graph.

[glend (Glen)]

Agree, change the scale on the graph, the present one could be hiding a lot. However, all that really matters is, are your stars round?

[Gavin1234]

Here’s the graph with a smaller scale. Also I think it’s already in arc seconds.

[Imme (Jon)]

I’d try some longer exposures.....somewhere between 2-4 seconds

[Gavin1234]

Ok I’ll give that a try. So what number should I be aiming for? I take it it’s the “Tot” number I should be using?

[Imme (Jon)]

My advice...forget numbers, forget graphs.

Look at your final picture. Are the stars round? If yes, your graph is fine.

There is no one size fits all due to different imaging scales.

[Gavin1234]

Ok cool well I think my stars are pretty round. Running a 30 min sub at the moment so I’ll check that one.

[luka]

As Jon said, increase the exposure time (next to Stop button) from 1sec to 2-4 seconds. Otherwise you may be chasing the seeing.