Currently, i have a 2x barlow and was thinking about getting a 3x barlow. Will this make a big difference in magnification? What about image quality? since it is a higher magnification, will image be more distorted and blurry?
You can get a range of magnifications with a single barlow by varying the path length between the barlow lens and the eyepiece (using focuser barrel extension tube(s)). I did a series of measurements on the UO 2" barlow (along with the Shorty Plus barlow; yet to write up the results for the site ). Typically I could get magnifications ranging from 2.1x to 2.9x depending on EP-barlow distance. View looks great at all mags.
More specifically, in answer to your qn, a good 3x barlow should be as good as a good 2x barlow. Yes it is big diff in magnification. For an 8" or bigger scope, atmospheric conditions ("seeing") will determine how high you can push the magnification before everything becomes a blur. If you are just starting out, just go for a 2x barlow and leave it at that. You will be able to use it with more EPs than a 3x.
Hi ezystyles, I have both a 2x and a 3x barlow, and as Steve suggests if they are of equivalent quality both give equally good images - at least at the same magnification. If you use the same eyepiece in both then you will get a much higher magnification in the 3x barlow and consequently will suffer more from poor seeing, objects will also appear fainter and more washed out just as if you used a much shorter focal length eyepiece.
The jetstream is making things very hard for the images to stay still. When I view saturn at high magnification ie greater than 1000x, the rings dance and ripple as the atmosphere moves.
This resulted in last nights saturn turning out like my attachment below.
I use a 5x powermate which can get to 7.7x and then I also used a feature with my camera to zoom in. I was testing last night and i reckon i am at around 1300x with this one.
I have had one great night in three months where i can say i have been able to use the 5x powermate properly, a handful of nights where it has been ok and the rest of the time, you get mushy images like this one.
As the boys say, at 2x and maybe a bit of zoom, this mushiness won't be visible and you will get sharper images, but the more magnification you start to crave, the times you can use it drop off real quick!
thanks Robert. More washed out with a 3x barlow than 2x? should I save my money then instead of getting a 3x barlow since i already have a 2x?
Cheers
really depends on what eyepieces you have, the scope you're using (the larger the aperture the higher the magnification you can usefully use - if seeing conditions allow), and what you want to view. For example if you had an 8inch F5 newtonian, it could usefully be pushed to max ~300x magnification under good seeing conditions and this would be useful for lunar/planetary viewing (but little else). If your highest mag eyepiece was a 10mm, this would give 100x, a 2x barlow 200x and a 3x barlow 300x. SO in this case the 3x would be useful to you on occasion. If you already had say a 6mm eyepiece the 2x barlow would have already pushed you to/beyond maximum usable mag limit so no point having a 3x in this case.
just looked up the word "powermate" another magnification eyepeice? learn new things all the time which now brings me to another question: will i get clearer and more magnification images from a powermate? it is quite expensive compared to a barlow, worth getting one instead?
oh, i only have the following eye pieces:
Plossl'' 4mm
9mm
25mm
2x barlow
tele 8" new 800mm f/4.
Thanks for your help guys. im thinking of dropping into Bintel this afternoon and getting something. abit itchy. definitely need to get a collimation tool.
I only have the 5x powermate for imaging. If I had very good eyepieces (which i don't), I would look at a 2.5" powermate down the track.
If you have good, but not great eyepieces, then you will not get the value for money out of a powermate.
I would stick with your current arrangement. The current set you have gives you 25mm, 12.5mm (25mm & 2x barlow), 9mm and 4.5mm (9mm with the 2x barlow) this is a very good range of magnifications.
What sort of scope have you got: 8" tele 800mm f/4 ie refractor / reflector??
The next step, I would be working out what great eyepiece you are going to be looking at down the track and then seeing how a 2.5 powermate would work with it. This is a big step! Not knowing your scope, i would be unsure as to what to suggest.
Go have a chat to Bintel anyway. I'd take the scope and EPs along and get the experts to look at it & help you with any queries you might have (collimation!!). I dare say they would not sell you something not appropriate for you and/or your present equipment.
Will do Steve. Might just take the eyepiece scope is kinda bulky to fit into the car. Probably take some pics of it with my digital camera and show them. Off to Bintel now can't wait.
also get their honest opinion on what sort of great ep's will work in your scope. I have looked thru some simliar scopes and there was a huge quality difference when compared to my 10" reflector.
I would hate for you to spend $300 on a 2.5 powermate and another $300 or $400 on a great ep, just to find the scope is the weak link in the optical train.
Just came back from Bintel . Got myself a russian TAL 3x barlow $50 and laser collimator $120. Realised that my primary & secondary mirrow wasnt align accurately. Took primary mirror out and placed center dot. now it is fully aligned.. im soo happy. Gonna give the 3x barlow a go tonight. Spoke with Graham about eyepieces etc. Told me can use 3x barlow but not with the 4mm eyepiece as my focal length (800mm) is limited. Very nice bloke and helped me out alot.
That TAL barlow was a top buy! I read nothing but good things about TAL stuff. And not a bad move to get a 3x instead of the usual 2x considering your scope is very short focal length. The laser is very handy for adjusting the secondary but not always sufficient for the primary IMO. You can always fine tune the primary with a star test.
. The laser is very handy for adjusting the secondary but not always sufficient for the primary IMO. You can always fine tune the primary with a star test.
hmm no wonder why after collimated, i look down the focuser, the mirror is still out even if the laser is straight. what is a star test?
). Typically I could get magnifications ranging from 2.1x to 2.9x depending on EP-barlow distance. View looks great at all mags.
The laser is very handy for adjusting the secondary but not always sufficient for the primary IMO. You can always fine tune the primary with a star test. 
