collimation question

[chris285]

i have a skywatcher explorer 130m but not put the motor on this yet, and during use i have had little sucess in observing planets. images of the moon have been great with sharp images and detail showing nicely, but planets have been fuzzy balls of coloured light

now i know that with planets the atmospheric conditions can affect this, but i have been viewing when the conditions have been good and still had problems so not used my scope in a month or so now

anyway i was wondering if it may be a case its not aligned properly, and if so would i still get the moon detail with it being much closers and struggle with other objects?

[NGC 1502]

Hi, the Moon can look good as there is so much detail to see, even if collimation is off a bit. You don't say which planets you observed, if it was Venus low in the west, then it can look dodgy even if the scope is ok.

You can check collimation by observing a defocused bright star at high mag, 150x - 200x. With it centred in field of view, see if you get concentric circles of light.

All scopes need to have cooled to ambient to work well but the 130 shouldn't take long, maybe 30mins or so. The 130 is well liked, as it is a nice scope, so don't give up !! Regards, Ed.

[Astro_Baby]

My 130 did well on Jupiter and Saturn. Mars hasnt been kind this year and Venus is a perisher. It sounds as if something is not right somewhere.

Can you say what magnificatio you have been usinf ? Has the scope been allowed to cool down ? Were you outside or viewing froma balcony etc - perhaps over the tops of houses which may be emitting heat haze ?

Lots of things can mess up the views with a scope. The 130 CAN do very well though so dont give up.

[chris285]

thanks for th replies, i think that i will check the collimation again to make sure it is alligned properly is a start

i have observed from my back garden, and i live on the outskirts of lincoln but still in an urban area so heat may be part of it i can't remember the exact location of i think it was mars and saturn i was going for and they may have been high in the sky but not sure

i do leave the scope out for around 30-45mins to adjust to the temp before i use, but i am still fairly new to this so i will check it and just keep going as i am getting better each time i use it

[Wizz]

Yes check collimation on a bright star, if the rings are concentric inside and outside of focus the most probable cause is the seeing conditions. DSO's (deep sky objects) nebulas, star clusters etc are less affected by the seeing conditions and you will see them well on most nights. Planetary detail and splitting tight double stars are affected greatly. On a normal night when viewing a planet you will get glimpses of great seeing only for a second or so and you will see great views but then your back to blurred views which is nothing to do with your scope or collimation, it's just the conditions. There's only a handful of nights a year when conditions allow you to crank up the power and the conditions are great, with more experience you will get to know when you get a "good" night rather than a "normal" night and the views you will get will be worth the wait!