Barlow lens problem?

[jezza]

I am using a X2 barlow on a Mak 127 scope with 25mm and 13mm WideScan eyepieces. The image quality is so poor that I don't use it anymore. Is this a common experience or a limitation of my scope?
Should I take it back to the store? Any help appreciated.

[Starkler (Geoff)]

Whats poor about the images you see?
Is it much better without the barlow?

A scope of your type needs to be at thermal equilibrium with the ambient air temperature. Try leaving it outside for an hour before viewing if you dont already do so.

[jezza]

A lot better without barlow. Image seems blurred and flat (lack of contrast). Thanks for replying so quickly.

[jezza]

Always do that when possible and it makes a big difference. The Barlow issue is something else.......

[Starkler (Geoff)]

In that case send the barlow back . Cheap barlows rarely satisfy and will make an expensive premium eyepiece look like cheap rubbish.

[jezza]

Thanks mate. Will do. I'll tell 'em Starkler sent me.

[iceman (Mike)]

What type of barlow is it?

to the forum jezza, how did you hear about us?

[jezza]

G'day Mike. Read about it in Aust Sky & Telescope. Love the site.
Barlow has been exchanged by shop for a more appropriate one for a MAK (apparently the one I had was more suited to a refractor (over my head))

[iceman (Mike)]

What type of barlow was it?
I've never heard of a barlow being suited for one type of telescope over another..

Thanks for the feedback, hope to see you back often!

[jezza]

Sorry I don't know brand of original, but new lens is GSO 2xBarlow Fully multi coated. (yes it's a cheap Taiwan brand, but will have to do for now) It has a longer tube than old one, if this makes any difference.
Have just read relating discussions on Barlows and am leaning towards an aprochramatic lens when I have the $$$$$. Seasons greetings all.
Can't beleive I missed the competition, but will still do for fun....

[asimov (John)]

Most refractor owners use diagonals. If the barlow's too long, it could hit the mirror before coming up against the 'stop'....This is possibly what they meant..

[videoguy]

Jezza

One of the loyal IIS members forwarded me the link to your thread and while I dislike getting into supplier debates on such things, I'm sorry to say that such feeback makes me feel outraged.
Mike..I agree and yes John, if the barlow is not placed in the correrct order, image amplification can seem rediculous but, this sort of feedback from a supplier is exactly the sort of cr*p (yeah ok..the word isn't that well disguised) that really annoys me. I can only imagine a handful of retailers that would spout such a line.

There are junk versions (supplied with 60mm refractors), medium to good low cost barlows, and great barlows with APO designs. But, none are made specifically for a MAK, Newt or refractor (in quality terms I should say) and if you've been told so, then your dealer has fed you a line.

Barlows are designed to yield increased magnifications for a specific eyepiece focal length in the order or 1.5, 2 or 3 X power. Indeed, the seeing will determine whether or not it can be used successfully at a given focal length, aperture and of course the overall quality of the optics (both the barlow and scope).

That's great news you have had the item replaced and noted a major improvement.

[jezza]

Thanks for the info Steve
And thanks all for your replies. This is my first venture into the world of online forums and I'm astounded by the amount of helpful feedback from such a simple query. I guess I've still a lot to learn. But that's half the fun.