Heritage 130P First light + barlow issue

[ScottT]

Hi,

I got first light on my new Heritage 130P last night! , it was a nice clear sky and I was able to spend a good hour and a half getting to grips with the scope.

I saw Jupiter and three of its moons , I could even just about make out two bands across the planet - I was blown away by this , I spent a good 40 mins just looking at this alone.

I looked at the Pleiades and Betelgeuse , which I likened to a tiny orange flame in the darkness.

Most of the viewing was done using the 10mm supplied ep , which gave pretty clear, crisp views.

I did have a problem with the Meade Barlow I bought though , whenever I put it on (with the 25mm or the 10mm) and looked at a bright star or Jupiter , all I could see was a large grey ball with what I can only describe as a black golf ball on a tee in the middle of it.

was I doing something wrong with the barlow , I did try to focus out as much as I could go , but the focuser fell out into my hand .

I was thinking that , if I was getting 65x mag with the 10mm , then the barlow should give me 130x and jupiter would be twice the size to my eye...

anyway . very very pleased I got to see Jupiter for the first time ever , I cannot wait to get out and look at some more objects.

thanks.

[Naemeth]

Hi,

I got first light on my new Heritage 130P last night! , it was a nice clear sky and I was able to spend a good hour and a half getting to grips with the scope.

I saw Jupiter and three of its moons , I could even just about make out two bands across the planet - I was blown away by this , I spent a good 40 mins just looking at this alone.

I looked at the Pleiades and Betelgeuse , which I likened to a tiny orange flame in the darkness.

Most of the viewing was done using the 10mm supplied ep , which gave pretty clear, crisp views.

I did have a problem with the Meade Barlow I bought though , whenever I put it on (with the 25mm or the 10mm) and looked at a bright star or Jupiter , all I could see was a large grey ball with what I can only describe as a black golf ball on a tee in the middle of it.

was I doing something wrong with the barlow , I did try to focus out as much as I could go , but the focuser fell out into my hand .

I was thinking that , if I was getting 65x mag with the 10mm , then the barlow should give me 130x and jupiter would be twice the size to my eye...

anyway . very very pleased I got to see Jupiter for the first time ever , I cannot wait to get out and look at some more objects.

thanks.

Did you try bringing the focus in? The Barlow usually brings the focus in, not out.

The focuser has fallen out for me too, luckily it's easy to put back in.

[ScottT]

I did turn the focuser in , but it wouldnt go any further and I could still only see the giant gray ball..

[Naemeth]

How quickly were you turning it? How far out was it in focus when it was without the barlow?

[ScottT]

I was turning it at varying speeds, it just made the grey ball larger and smaller , unfortunatley I cannot remember how far out it was when i was viewing it with the 10mm..sorry ..thats not much help...

[Naemeth]

Even at 130x, Jupiter will still be pretty small. Sounds like the focus wasn't far in enough.

I'd recommend turning the focus slowly one way - if that makes it larger, you've gone the wrong way. Then go the other way until it stops making it smaller, once it goes larger, go back the other way and you should get a sharp or fairly sharp focus.

[ScottT]

ok thanks, I will try that as soon as I can get out again.

So from what I have read online, the black 'golf tee and ball' was prob due to it being so far out of focus (it is reflecting something within the scope itself)

[Naemeth]

ok thanks, I will try that as soon as I can get out again.

So from what I have read online, the black 'golf tee and ball' was prob due to it being so far out of focus (it is reflecting something within the scope itself)

You were probably seeing the spot on the primary. It's a good idea to focus on something easy, like the Moon and then keep the focus there, as long as you keep the same eyepiece, focus won't change between targets (unless the scope cools down between focusing and when you are on the object)

[knobby]

Which ever way you turn the focuser to make the donut look smaller is the way it needs to go

[ScottT]

You were probably seeing the spot on the primary. It's a good idea to focus on something easy, like the Moon and then keep the focus there, as long as you keep the same eyepiece, focus won't change between targets (unless the scope cools down between focusing and when you are on the object)

ok, I did try focussing on something and then trying it with the barlow, I got jupiter nice and clear with the 10mm , then dropped the barlow in and the issue occured..

[Naemeth]

Try and get the Moon in focus with the barlow, then move to Jupiter .

[ScottT]

Ive just been out again tonight, Although the moon is not up there yet , I put the barlow in to take another look.

I noticed that as soon as I put the barlow in , the donut image appears (I can see it if I look down the barlow on its own) , when I put the eyepiece in , it obviously makes the donut much bigger, I can turn the focuser all the way in until it wont go any further and the donut is still there, just much smaller.

Im getting the big donut even if I have a star lined up , in this case Capella, It seems to need another 2-3 twists of the focuser.

The barlow is a : Meade Instruments #126 2X Barlow - 1.25"

I dont understand it as I have read posts from people who are observing Jupiter with the same scope ep and barlow and are getting good results.

[ScottT]

I should add that the posts I have read have not stated they are using the same model barlow , just that they are using a barlow of some sort.

[Naemeth]

Have you tried moving slowly from the inner most point on the focuser? Try that, and slowly. If it doesn't help, I've no idea what to suggest.

[SamAndrew]

One thing you can try on a colapseable dobsonian is to not fully extend the scope, that might give you enough in focus

[knobby]

Not ideal but it may get you going, try unscrewing the bottom off the Barlow ( the lens part) and screw it onto the bottom of the ep.

[Naemeth]

Perhaps the flex tube isn't extended fully?

[AndyWB]

Re: the golf ball tee - I've seen that when mine is out of focus - I'm pretty sure the 'tee' part is the support for the secondary (only 1 on the Heritage 130), so I think what we're seeing is actually the shadow of the secondary and support - which implies a focus issue.

Personally, I'd try knobby's plan - focus whichever way makes the doughnut smaller, - and if that fails, try not fully extending the truss. Though that does suck as a solution.

[ScottT]

Yes, the golf tee is the mirror at the top and the arm that holds it , if I look down the tube I see where that image comes from.

I cant focus any smaller , I just cannot twist it anymore past that point.

I will try not extending it fully, but im confused as to why nobody else seems to have this problem, I dont want to have to do this if I can help it , especially as when it gets cold , the metal contracts and I cannot push or pull it , i have to bring it indoors to heat up again.

I will see if I can borrow another barlow from someone and try that out, even tho im a newbie , Im suspicious of this lens now...

[ScottT]

Thanks for the help everyone and thanks Knobby , I will try doing that as well.

[ScottT]

Last night I got to try out another barlow. It produced the same issue , I did try retracting the scope a bit, but to be honest after trying my friends 4mm and 6mm ep's I think I will settle on a 5mm and be happy with 130xmag.

The 4mm on Jupiter was almost there, like within a nat's whisker of being perfectly focused , so I think the 5mm will be fine, I'm very happy with the views of Jupiter I have been getting the last three nights.

I also saw Orion's nebula for the first time last night

[Delima05]

I believe your telescope isn't powerful enough.

Othewise when you put ur barlow in, don't jam it all the way down the aperture. but instead to try half way and turn your screw tight. there should be a sweet spot where it starts to work.

i have a thread just a few up as a newbie having issues focusing with barlow and other high power lens.

[SamAndrew]

I've just bought a heritage 130p as my grab and go scope, I've got a cheap skywatcher 2x and a tal 3x barlow, so i'll report back if either of those work.

[CraigT82]

I've got this scope and with a 5mm BST eyepiece it gives nice sharp images at 130x. the only barlow I have is a 2x skywatcher one that came with the scope... and the only thing I use that for is to barlow my laser collimator, it's pretty rubbish for anything else.

You could try what Delima05 suggested: Don't put the barlow all the way into the focuser, , you can get extra out-focus doing this and you should be able to rule out not enough out focus as your problem. You could even just remove the focuser altogether and hand hold the barlow/ep in the opening and move them up and down slowly and steadily whilst looking through to see if you get sharp focus anywhere... needs a steady hand mind!

Craig

[ScottT]

Thanks for the suggestions, after doing some research it seems the easy way around it us too retract the tube a few inches, havent had a chance to try yet because of the cloud.