let me see your guide graphs!

[Micke187]

Well im out and doing some imaging and i think this graph on PHD2 is the best i have ever had.
I have always struggled to be under 1" before but tonight i have had a record. The graph has stayed under 0.6" almost the entire night !

[JayTee]

Hi Micke,

Congrats on those results, that's very impressive. Most folks don't realize that to get results like that it is a team effort. You, the user, your mount, and PHD2 all have to work together to achieve results like that.

About showing you a picture of my POS guiding graphs, I think not. The last time I was out I could not get results below 2.0" RMS.

Please tell me your stars were round,
JT

[Micke187]

Oh the stars a practically perfectly round so im very pleased.
here is a single sub i took on M1 tonight.

[Juno16]

Well, Micke187, that is very impressive and I have never had a graph that looked like that.

I am imaging right now too, but I am not going to show my graph because it looks pretty rough. Averaging about 1.5". Stars look pretty good though, so no problem here. Pretty much normal.

Well, I cleared it and here is a piece before the sawing starts! In fairness though, the seeing is poor.

Good for you! Keep it up.

What is your target? I am shooting the Flaming Star right now waiting for the Rosette to get high enough (>40 degrees) to start clearing the city lp and not blow out the histogram. I can see nothing but the star in the subs!

Great guiding man!!!!!

Jim

[UlteriorModem]

You sure that was not a hot pixel?

Outstanding, I don't think I have ever gotten even close to that.

[bladekeeper]

Nice graph!

My last one looked like it fell out of an ugly tree and hit every branch on the way down.

I'm off to kick my mount now.

[Micke187]

Yeah i hope i can get these kind of result in the future to when i step up to a longer focallenght then i got now so. But yeah the graph result are very surprisingly good! And the starshapes are as round you can get them.
The target for tonight is M81/82. I thought i would have a little chance of getting the IFN with more luminans and also HA to try to pull out the red from M82. Maybe i can get the post-process done before new year

[Micke187]

You sure that was not a hot pixel?

Outstanding, I don't think I have ever gotten even close to that.

Haha yeah it almost look like it could be but na that star im aiming must be a very rare stable star indeed!

[Micke187]

Nice graph!

My last one looked like it fell out of an ugly tree and hit every branch on the way down.

I'm off to kick my mount now.

Thanks!
Haha! Yeah my graphs i have had before feels like it might look the same as you are describing. But it might be alot of luck im having tonight
And it keeps on going !

[Juno16]

I switched to +/- 2 px and my graph is still far worse than yours!

Stars still look good though!

Thanks,
Jim

[Lady Fraktor]

If your bored check out some of the charts people at CN have posted using the Vixen SPX mount.

[JayTee]

Not to be a buzz-kill here, but the fact that you're Imaging so close to the pole does account for some of the greatness of that guiding graph. Let us know how well your setup does when you image an object closer to the celestial equator.

Cheers,
JT

[yobbo89]

outstanding hot pixel guiding ahahaha!

just joking, i was going to insert a hot pixel guide but i can't find any screenshots.

I typically get as low as 0.3'' to 0.5'' in a particular spot and on average 0.7'' , and on the meridian flip it can be a hit in miss.

There's a giant clockwork to it, offset weight,''hypertuning'',sky condition,fine tuning phd settings.

i guess you're ready for 30 min subs !

[yobbo89]

clear skies tonight for new years eve, so i get to screen print a guide graph .

it's alright , typical .4'' to .7 '' it's really all i need (0.65'' imaging resolution) , images don't really suffer if the guide spikes to 0.7'' for half a second . i had a play with the backlash settings,worked out alright.

[Juno16]

I should start a guide graph thread for AVX users!

[yobbo89]

yeah i hear that the avx is a tricky one which usually needs a heck of a tune.

[Mac]

Stellar Mate 1.4.6 running on Raspberry Pi 3

[Micke187]

And yeah the declination of the object (messier82/82) is rather close to the pole so it can indeed be the case of the good guiding i had. Hopefully soon i can try out on objects like the orion nebula thats closer to the celestial equator to see how it will behave.
And it will also be interesting how the mount will handle a more heavier tube in the future. I will get a 130mm or a 115mm refractor for galaxy hunting. So if i will keep get these kind of graphs it will be a very happy But i think a mount upgrade will come either way i think.

[Mac]

yeah i hear that the avx is a tricky one which usually needs a heck of a tune.

I was able to get the best guiding after using the polar alignment feature, but it sure it time consuming. The slew rate can be increased but it reduce accuracy. This was after using the polar scope to get initial alignment and it was around 5' 30" off. Obviously I need better initial PA with the scope too.

Is 1'44" good for polar error? Seems still a bit high to me. I noted where the polar scope was after the final alignment as compared to the starting point and it wasn't that much.

What kind of additional tuning needs or can be done to the AVX? I've seen PEC mentioned but never looked into what's involved.

[Juno16]

yeah i hear that the avx is a tricky one which usually needs a heck of a tune.

I was able to get the best guiding after using the polar alignment feature, but it sure it time consuming. The slew rate can be increased but it reduce accuracy. This was after using the polar scope to get initial alignment and it was around 5' 30" off. Obviously I need better initial PA with the scope too.

Is 1'44" good for polar error? Seems still a bit high to me. I noted where the polar scope was after the final alignment as compared to the starting point and it wasn't that much.

What kind of additional tuning needs or can be done to the AVX? I've seen PEC mentioned but never looked into what's involved.

Steve,

I am not familiar with your software, but if you get guiding values similar to your posted graphic on a routine basis, personally, I wouldn’t change a thing. My guiding is usually challenging and as JT said, it is always better In the northern part of the sky.
Sometimes, I will shoot an image or two where the total arcsec rms error in PHD is under 1”. That is rare though. If I am between 1.2” and 1.5”, I am happy. From what I’ve read, this is typical performance from an AVX.

I have removed the two brass drive gears on both axis, buffed with a tooth brush and polishing compound and adjusted the clearance to minimum (no binding). I reduced tension on the RA axis so that it swings freely. I have tried pec, but it made little difference.
I am sure that I have some flexure, but I don’t fee like tackling another round of cable management right now.

I am very happy with the mount and can live with the guiding. I get pretty decent stars even when I am having a rough night.

For PA, I use Sharpcap. That is all that I use Sharpcap for. I have some bricks set in the ground to set the tripod legs on so I don’t use the polar scope anymore. Takes about 5 minutes to get 1-1 1/2”. I believe you are okay with up to 3” of PA error.

Didn’t mean to get long winded! Just my take!

Jim