PHD question

[graham.hobart]

Hello all
When I had my 110mm refractor on my PMX I had a flat PHD graph (ish) and a an rms in low 20's 0.22 etc.
Now with both the RC 10 and the 110mm on it (it is well balanced) I have rms in the forties 0.44 ish and RA and DEC small spikes around the base line.
I possibly changed my PA a tad when I rejigged the scopes around but does this represent ..
a. I need to re do my PA again?
b. I have overloaded mount?
3. Or do I need to change settings on PHD?
I should say I am guiding the rc 10 (at 2000mm fl) with a modified finderscope and a lodestar in a 2 x barlow.
Maybe the guidescope corrections are not the right scale for the focal length? (I have just bought a second hand OAG so maybe this will solve it when it arrives?)
Cheers for your thoughts brains trust!:thumbsup: Graz

[graham.hobart]

bump!:D

[graham.hobart]

correction OSc index 0.42-0.36, RMS 0.22

[lazjen]

If I'm able to use an RC10 on a G11 without too many difficulties, I doubt your PMX mount is going to be a problem.

I would suspect you'll have to do your PA again - well verify it anyway.

Are you using PHD2 btw? It's an improvement over the first version and can display more info in the graph, including its thoughts on your PA.

Finally, as my setup is not fixed, I find that I get RMS all over the place depending on how well I've done PA. Sometimes up to 0.6. I remember seeing 0.07 one time. I think I probably see 0.4 to 0.5 most often.

[peter_4059]

Could also be seeing - try the simulator in PHD2 - you can change the simulated seeing and other parameters and see the effect on RMS.

[graham.hobart]

Will try PHD 2 -cheers
Graham