PHD Log Analysis

[AndyUK]

(And yet another PHD query...!)

After much faffing around last night with a troublesome RA graph line that kept wanting to wander away above the central line, I finally resorted to the original settings which appeared (at first) to work well, and after that hiccup, I thought my guiding last night looked pretty good... but then again I didn't watch the graph for all 6 hours. However, when I started looking at the subs, over 1/3 were naff.

So I found the log file and produced the attached in Excel - I THINK DEC looks okay (ignore the first bit - I was b*ggering about ), but RA goes all over the shop after the first few minutes (which is when I was watching it)...

I've also attached my PHD settings - I did try messing around with the Max RA duration (not included in this graph) by raising it to 200, but it was worse than the "default" 150 setting so I tried it at 120 (again worse than 150) so I put it back...

Do I need to perhaps adjust RA aggression (if so, any clues roughly how much, and which way!?)

I'm using a finderguider by the way (hence the calibration being high and the min movement being so low!)

[swag72]

I had a play before I switched to Maxim, and my RA agressiveness was at approx 85. My understanding is that is your RA graph is moving alot, then you need to decrease the agressiveness. Alternatively, try Maxim!!!

[AndyUK]

Cheers Sara - Although I hadn't seen your advice, I had a play with my RA aggressive settings last night anyway (and guessed at the other way - 110). Having only used PHD a few times, I'm still struggling with it (and yes, I know I probably ought to use Maxim instead!), but I think it might have worked last night... assuming that I'm trying to get everything as flat as possible(?). This is what I got last night:

The things I think I'm happy with (and understand changing) are the min motion, exposure and calibration settings... and I think I'm happy that if I get a dodgy graph, then the setting to play with is RA aggression - We'll see what happens tonight, but if it starts playing up again, I'll tweak it down a bit. I believe that increasing it would have increased the possibility of over-correction, but (perhaps) in my case (with my mount etc) that's what it needed...

[swag72]

Blimey Andy - That's a great graph there!! Lovely and flat!!

Glad you got it sorted - No thanks to my duff info!!!

[AndyUK]

Hi Sara - I don't think it was duff info... and I'm not sure I really have it sorted - I've had a graph nearly like that before, but for some reason, without changing anything, it decided it didn't like those previous settings after all... and last night it liked these settings!

If tonight's graph comes out anywhere near this one though, then I might be persuaded to continue to use PHD a while longer...

[malc-c]

This is what I got last night:

Andy,

I wish my graph was as good as that !

Sara,

I'm using a QHY5 camera with the ascom driver - for the life of me I can't see how to set this up in Maxim.. any pointers

[swag72]

I don't use anything to do with ASCOM, so not sure I can help you on that score. I must have used the QHY5 driver on Modern Astronomy for the updated driver.

I'm racking my brains how I got it all to work, couldn't have been that difficult for me to sort it. I'll have a think and a look!