Focussing on Jupiter

[Mad Taff]

Hi Everyone. I have had my 200p on EQ5 for over a week now and have had some enjoyable observing due to very clear skies recently. I have read here that the standard skywatcher eyepieces and barlow you get with the scope have their limitations so I got myself a new 8mm BST Explorer eyepiece. On trying it out the other night It gave me fairly good images but when I barlowed it x2 I could not resolve Jupiter or its moons - they stayed blurred. Could this be the quality of the barlow but it works ok with the 10mm eyepiece? I checked collimation the following day and both mirrors were slightly out. I have fixed them and will check again before I go observing next time. Any comments or suggestions welcome. Many thanks - Phil.

[leelee970]

It could be you've not enough focus travel to bring the 8mm + Barlow in focus - just a thought.

I've several extensions that I have to use for such situations

[leelee970]

sorry about font size ????

[Cornelius Varley]

Formatting removed for you.

[Stargazer_00]

I have a 5mm bst which I can Barlow and focus on a 250p no problem id be surprised if there is any difference between our scopes

Sounds like something else to me although I'm not sure what

[andyman]

i had the same problem on my 250flex when using a barlow shorter eyepiece fine longer eyepiece couldnt get in focus had to get a extender

[Mad Taff]

Thank you for your comments. On the next clear night I'll give it another go. If I have the same problem then I will have to try a focus extender. Many thanks again - Phil

[rwilkey]

Hi Phil, I would find 250x a bit much for my 200P on most nights of the year, could be just atmospheric conditions with high misty cloud preventing good views, at least that is my experience here in Swindon.

[Stargazer_00]

That's a good point, it may have been in focus but because its a very high magnification chances are it looked not great. I did say about about finding focus ok on a 5mm bst barlowed, but that looks so awful i never do it as the images are dim and i see so much less detail on jupiter its rubbish. Much prefer it around 150x