Eyepiece or Barlow?

[Camperman]

Had an excellent night in the garden last night using my skyhawk 1145P, and tried out a new 6.3mm plossl eyepiece - purchased after reading the excellent sticky thread re eyepieces, and wanted to extend my collection. I have only been using the 10mm and 25mm eyepieces and the 2x Barlow that were supplied with the scope before last night.

Got the best view of Jupiter yet by using the new eyepiece, the bands were visible although appeared to be coming in and out of view which I assume was down to the seeing conditions, and the moons were nice and sharp. This compares to similar but not so sharp views when I used the 10mm eyepiece with the Barlow previously.

I thought I'd get adventurous and use the new eyepiece with the Barlow, and couldn't get a sharp image no matter what I tried.

This may be a daft noob question, but what might be the problem? I think it may be because I am trying to magnify too much (is x160 too much for a 1145 scope?), or possibly that the barlow isn't of a good enough quality. Is it possible that I am missing something?

Finally, if I want to increase the magnification, what would be the best way forwards?

Thanks,

Rob

[brantuk]

Yup - the "seeing" will do that to planets - sometimes they appear to "boil" cos it shifts so much. The advert for your scope says the max usable magnification is 228x but in reality most viewing is done around 150x to 200x.

I never went much above 180x with my old 130P which was more than enough. Sometimes it's better to view a smaller but clearer and more contrasty image.

Your scope is f4.4 which is very fast. You will find that better quality eyepieces will be more effective than the supplied basic ones

[Camperman]

Thanks Brantuk,

Do you think it is worth investing in a new Barlow or it would be better to look at eyepieces individually?

Not sure what my budget is yet, and I would imagine that you get what you pay for, but what would you recommend as being a suitable quality for my scope and experience?

Having had a look around, £20-30 per eyepiece seems to be where I thought appropriate (plossls). I am wary that I am at the beginning of what is likely to be a long road that will involve an upgrade in scope at some point and want to make sure that any purchases are also going to be useful in the future.

I've seen the eyepiece sets advertised, and have seen mixed reviews for them in terms of how many would end up actually being used. Does anyone have any advice?

Any help is most welcome.

[andrew63]

A way forward, especially from an economy viewpoint is to purchase used. There is a for sale site which will be returning here shortly, and astro buy and sell. I have found both excellent as you can get better quality kit much cheaper than new. Something to consider.

andrew

[mdstuart]

I would from experience go for an eyepeice rather than a barlow. A good second hand plossl of any sort would be a start. It is always re-saleable on astro buy and sell...Or get one of those 66% field of view TMB or BST eyepieces for about £40..

Mark

[hemihaggis]

a handy equation is ...

focal lenght in mm divided by eyepiece in mm ,,this will give you the mag with any given ep ..

your scope would be 1000mm divided by 8mm (ep) = x125 mag ,

only on exeptional night s at a dark site will you be able to increase the mag much more than this .

cheers

[Tinker1947]

Adding a Barlow adds more glass for the protons to travel through, EP's are really the way to go, the best you can afford will make for happy viewing..

[Camperman]

Thanks for the advice - I think it has helped to focus the mind. No pun intended!