Barlow advice please...

[Drakester]

Hi.

I'm looking to get a 3x or 5x Barlow / Telextender for my Meade 5000 127mm. (FL 950mm) refractor.

My smallest EP is a 9mm, which by my reckoning would give 317x and 528x magnification.

...this is basically being driven by the fact that Saturn still looked pretty small with the 9mm EP and 2x barlow. (211x)

I'm being drawn to getting the 5x barlow, but am I missing the point here and will I lose detail or resolution... or focus?

Any help appreciated!

Cheers.

[dweller25]

Your 127mm refractor is good for x250, maybe x300 MAX.

I have a 128mm refractor and stay around x225 but have used it at x294 when the seeing was very good.

[NGC 1502]

...this is basically being driven by the fact that Saturn still looked pretty small with the 9mm EP and 2x barlow. (211x)Cheers.

If you were viewing Saturn very recently, it is way past its best for

this year, so you were not seeing it as well as you can.

211x is actually a fairly high power. Are you able to borrow a barlow

or higher power eyepiece to see how you get on ?

I much prefer a smaller sharper view than bigger and fuzzier.

Regards, Ed.

[Drakester]

Thanks guys. Saturn was just last week, and the scope was almost horizontally pointing west, so I guess I was viewing through an awfully large amount of atmosphere...

Dweller, what happens if I push magnification above 300x ?

Cheers.

[dweller25]

Thanks guys. Saturn was just last week, and the scope was almost horizontally pointing west, so I guess I was viewing through an awfully large amount of atmosphere...

Dweller, what happens if I push magnification above 300x ?

Cheers.

The image gets softer with no additional detail. It's best to use a lower magnification on Saturn - around x200 as it's sharper.

[spaceboy]

A 9mm will give you x105 or x316 with a 3x barlow. More often than not UK seeing dictates how much magnification is practical. Usually around x200-x250 on planets. There are times when it allows for more but these are often rare. Your scopes practical maximum magnification is around x254 so on good night you would be looking at a 4mm EP giving you x237. Trying to use too much magnification will not see you gain anything by it and in fact it will probably worsen the image due to the decrease in exit pupil dulling the image not to mention the puddle effect you will get from over magnifying. More aperture might improve things for you but this would mean buying more than a barlow.