Help with a 6 Inchhhh MAk

Sma012 (John) · #1 10-09-2009, 08:58 PM

Hello everyone. If you could would someone be able to help?

I just got a 6 inch Maksutov Cassegrain back from repairs and i'm having some trouble but i don't think its from the repairs. Its set up which is good and my finder scope is alligned well, atleast compared to my previous attempts.

I'm assuming its colimated and its been sitting outside for a while to adjust to the cold.

Looking at the moon a couple days ago with my standard plossyl eyepieces it was great, spying on me neighbours 10 minutes ago it was even better BUT now when i come to stars it doesn't find anything. I can see through my finder scope plenty of stars that i can't see through my naked eye but when i get to look throught the optical tube i see nothing!!!!!!!!! and its killing me.

I thought i would see something but its as if it was completely out of focus, so i turned the focus knob all the way right and all the way left but i still get nothing. NOte: Works great on a house a kilometer or so away. Focuses and defocuses appropriately.

Does anyone have any suggestions about what might be wrong or whatr i might be doing wrong?

There is some light pollution but i still expect to see something, especially since i can see things through my finder scope.

Would appreciate any help tremendously!

Robh (Rob) · #2 10-09-2009, 10:29 PM

If you saw the moon clearly, there shouldn't be any real problem.
What is your eyepiece? Perhaps your field of view is so small and your finder is slightly off axis so that you are looking into a relatively starless field.
I would suggest starting off on a low magnification. Centre alpha Centauri in your telescope then check and centre the finder. Try a higher power (around 150) then centre in telescope and finder again. Can you see the two stars in alpha Centauri clearly? Then try some bright objects like omega Centauri or 47 Tuc.

Regards, Rob

torana68 (Roger) · #3 10-09-2009, 10:31 PM

the only thing that springs to mind is you didnt align the finderscope. You cant miss the moon but you can miss little things if the finder scope isnt spot on, especially with higher powered eyepieces. Jupiter should be easy to spot and find with a 20mm or larger eyepiece then adjust the finder.
Roger

Wavytone · #4 10-09-2009, 11:30 PM

Quote:

Originally Posted by Sma012

its been sitting outside for a while to adjust to the cold.

I'd guess the corrector has dewed over. Take it back inside and let the dew evaporate.

A 6" doesn't need to be outside for hours; better that it is slightly warm to stop the dew.

Sma012 (John) · #5 11-09-2009, 11:51 AM

Thnks Roger, Rob ad Waverton, quick responses are great!

I'll try viewing again tonight with it just outside for a bit. Although i did that yesterday and the same thing happened.

As for the eyepiece, i used a standard 30 mm plossyl that came with the scope. I have a 10mm but its harder to see through so i haven't quiet put it in action yet. I'll try brighter stars and jupiter tonight to see if i can get anything. Unfortunately my computer is down so i can't think

Roger,

As for missing things, even if i did miss a smaller star wouldn't the telescope expose all the stars in that area that im looking at anyway and something would come up? My telescope just shows nothing but a dark, navy blue. From my understanding there are stars everywhere in the sky we just can't see them because they are being overpowered by other light or our eyes aren't powerful enough to see the light they emit. Which is why we have telescopes and the more powerful your telescope the more it can bring out, I know my telescope isn't the most powerful but i figured it was enough to illuminate the stars i'm talking about. Unless of course, there are parts of the sky that when pointed at with a 6 inch mak you don't get any picture because all the stars are too far away. I'm not sure what the FOV for the plossy i have is. Can't be that small though, if what i'm saying above is correct.

Please, if i have the wrong understand correct me. I always welcome it.

I haven't ever seen the night sky through another telescope so i don't know what kind of powered telescope you need to expose most stars.

P.S THANKS for your help again.

PCH (Paul) · #6 11-09-2009, 02:25 PM

Point it at the moon and make sure you can see that clearly and well focused. Then, have a look with your eyes at a bunch of stars, or anything bright like Jupiter, near the moon. Then just move the scope slowly in that direction. The stars that you can see with your eyes should become visible through the eyepiece. It shouldn't be any harder than that. It's got me stumped if the stars don't come into view

Cheers,

torana68 (Roger) · #7 11-09-2009, 04:53 PM

"As for the eyepiece, i used a standard 30 mm plossyl that came with the scope."

stick with the 30 for a while

really with that you should see something nearly everywhere, do you have a brand name and model of the telescope?
Roger

Sma012 (John) · #8 12-09-2009, 10:55 AM

Yep, Its a Saxon 150mm Maksutov Cassegrain. 1900 focal length. Seeing what it can do to the moon, i feel like replacing it with an 8inch from Skywatcher

Thanks to you to Paul. I don't think there are any stars near the moon that i can see at the moment with my naked eye but i will try!!!!

Unfortunately yesterday jupiter was too high up for me. So i didn't get a chance to look at it. I plan on going out tonight to get it when its a bit lower.

torana68 (Roger) · #9 13-09-2009, 06:05 PM

Quote:

Originally Posted by Sma012

. I plan on going out tonight to get it when its a bit lower.

how'd it go?

PCH (Paul) · #10 14-09-2009, 12:18 AM

Quote:

Originally Posted by Sma012

Yep, Its a Saxon 150mm Maksutov Cassegrain. 1900 focal length. Seeing what it can do to the moon, i feel like replacing it with an 8inch from Skywatcher

Thanks to you to Paul. I don't think there are any stars near the moon that i can see at the moment with my naked eye but i will try!!!!

Unfortunately yesterday jupiter was too high up for me. So i didn't get a chance to look at it. I plan on going out tonight to get it when its a bit lower.

Well how did it go from me too? Incidentally, what did you mean by Jupe being "too high up"? Please let us know if you've had any joy with this exercise

Sma012 (John) · #11 14-09-2009, 11:03 PM

Sorry guys, i haven't conducted the acitvity yet. The clouds are covering everything tonight and last night i got home really late while needing to get up early today. Its just been a real busy week this week.

What i meant by it being too high up is that my telescope is on a blacony. All loghts are off so there isn't any obstruction but the when i try to hit jupiter with the telescope on the edge of the balcony i can't get it because the roof is on the way. Going to go into the garden for it next though, so that should clear that problem up.

Sma012 (John) · #12 15-09-2009, 07:43 PM

Hey GUYS!!!

Alright got to do it. Focused on Jupiter it did alright using the 30mm plossyl it brought it up as a nice small sphere. Using the 10mm plossyl it did the same just magnified and a bit more fuzzier. not much. Tested it on a star as well and i saw well!!!!!!! Focused and de focused and i could see very faint stars around it so that was good.

Everything went well and everythings working i now just need better conditions some better equipment and a good collimation.

THanks for your inputs!!!!!!!