Collimated or not?

[Treewick]

I have a new Z10 and have been unable to get the clarity I would expect when viewing Saturn. I am not sure if it is the collimation or the atmosphere conditions. The collimation was a bit out of whack when the scope arrived so I made some adjustments. Below is a picture I took with my iPhone through my cheshire EP. Can anyone comment on if it is in proper alignment and if not what I should be looking at here that I am not seeing? I can see the ring on the primary is centered in the reflective tape of the cheshire. It looks as though the entire secondary is visible - Where I get lost is trying to understand how much of the secondary mount I should be seeing or if it matters that the reflection of the mount appear oblong.

Thanks,

Todd

[Mr Q]

Looks OK to me. How much clarity is a very subjective term - each has their own definition or value. So below is a link showing what Saturn (and other planets) look like in varying stages of mis-collimation. If you want more clarity than the "good collimation" image, good luck in your quest for perfection.http://legault.perso....fr/collim.html

P.S. Look at the images at the end of the article

[fatwoul]

The Z10 is pretty fast, correct? f/5 or so? Looks like I'd expect, really. Fast newts always look a little offcentred like that when collimated. I think the offcentring is in the right direction, too, based on the orientation of the secondary shadow.

EDIT: Have you confirmed collimation with any other devices, like a Hotech laser? To be honest I trust a Cheshire more than any other instrument these days, but if you don't want to fork out for a Hotech, you could try barlowing a cheapy laser, which always worked very well for me.

[umadog]

It's pretty good. The primary isn't quite centrered in the secondary. You can see it's over to the right slightly. But that's not an axial alignment so it's less of a big deal. You an draw circles and lines over your image to double check. It should look like this: http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Board=reflectors&Number=3033065

[Treewick]

Thanks for the replies.

Mr Q. - thanks for the thread link. Very informative!

Fatwoul - scope spec sheet put the FR at 4.92 so I am definitely in the range you mentioned. I have been trying a two step collimation process with a Hotech self centering laser first then fine tuning with the cheshire. I think the issue I am having is the SC laser is 1.25" and the scope focuser is 2" with a reducer so I still have to account for some play in the reducer it sits in. Its a Crayford focuser assembly so there is not as much play in the tube as there is on the rack and pinion focuser on my 6" orion (I thought it was virtually useless trying to use the laser with that). Im using the set screws on the secondary to put the laser in the center of the primary, then adjusting the primary to put the laser on center in the Hotech. Then Im tweaking the set up with the cheshire.

Umadog - would that be an adjustment on the main retaining screw on the secondary mirror assembly?

[x6gas]

Looks okay to me too...

Is your laser collimator collimated correctly? That's a common problem!

Also one thing to remember - if there is play in the seating of your laser collimator then there probably will be with your eyepieces too so you need to weigh up the law of diminishing returns here...

[Saleratus]

You look well collimated, though you could get a higher level of precision with an autocollimator.

My guess is that the seeing is to blame for your problems getting a good view of Saturn. Because of the high magnification needed, planets are a lot more sensitive to seeing conditions than deep sky objects.