help with phd 2 guiding advanced setup

[doseri]

hi

Any advice on how to setup of PHD2 , I'm using ST-80 with meade dsi pro , and main scope gso 200f/5 with canon500d ,i was trying since 4 nights unfortunately i can't get any luck to get the optimal perimeter in PHD2 for guiding over 5 minutes. my guiding graph was spiking in both access and i don't know where the issue is attached is my advance setting

regards,

sam

[Roger B]

I've never used PHD2   but a couple of things stick out to my PHD settings

Min move pixels mines set to 0.25  0.06 may be too small
and your dec guiding is north,  mines Auto    If it bounces back an forth,  try reducing the aggression

Roger

[chris.bailey]

Yep, plus dec algorithm as "resist switching". Having Dec guide as North only AND with Hysteresis as the algorithm with quite aggressive settings will mean overshoot occurs and because it can only issue guide corrections in one direction, it may never get back again. If guiding corrections are constant back and forth then reduce aggressiveness. 85% is quite aggressive.

With a fairly wide field setup you can afford the guiding to be quite relaxed so I would set minimum guide to about 0.3 pixels and turn aggressiveness down to about 60% and see how that runs.

Chris

[doseri]

Can you share your phd guiding setting with me

[chris.bailey]

Mine is currently setup for a very different guide setup so you don't want mine but plug in what Roger and I have suggested and give it a try.

[doseri]

my guiding  scope is orion st-80 & meade dsi pro 1 guiding cam ,any more Suggestions ????

is there any calculating  software ????

[doseri]

hi

in the attachment you can see the phd graph

[Einari]

That doesn't look bad (if there are no bigger spikes).
Are you getting round stars now ?

Like Chris said try these:
"set minimum guide to about 0.3 pixels and turn aggressiveness down to about 60% and see how that runs"

[doseri]

 I try last night but no lock to get good round stars , i do not know what's is the issue

[chris.bailey]

Most of your guide corrections on that graph are in one direction in RA and all of them in DEC. Its therefore constantly undershooting. Increase aggressiveness and if necessary increase the guide speed (probably set at 0.5 sidereal). I would still expect reasonable star shapes from that however based on an RMS of 0.27.

What mount? Are you sure the star shape is not a function of collimation or tilt?

[swashy]

I'd agree, the graph dosen't look bad, can you post up your image results

[doseri]

 My mount is the sky watcher neq6 pro., only 1 year old
Yes I think that from guiding if I do 3 min shoot the stars very sharp

[doseri]

I'd agree, the graph dosen't look bad, can you post up your image results

Yes I will upload the image

[doseri]

Most of your guide corrections on that graph are in one direction in RA and all of them in DEC. Its therefore constantly undershooting. Increase aggressiveness and if necessary increase the guide speed (probably set at 0.5 sidereal). I would still expect reasonable star shapes from that however based on an RMS of 0.27.

What mount? Are you sure the star shape is not a function of collimation or tilt?

The skywatcher neq6 pro

[Einari]

Maybe it's field rotation then if 3 min exposure looks okay.
You've done proper polar align ?