Quote:
Originally Posted by mental4astro
Hi Jo,
Eyepiece wise, while barlows 'do' work, in the end they tend to just get in the way. As others have suggested too, you would be better off with a dedicated high magnification eyepiece than with a barlow. Another thing they do is add considerable weight to the top end of a scope if coupled to a large eyepiece.
Another thing not ever mentioned about barlows is that not all eyepieces work well with them. This is compounded by the optical system of the scope you are using. A barlow can alter the shape of the light cone to such a degree that an eyepiece that gives you a nice image neat, becomes terrible when the barlow is employed. And not all barlows are built the same way: my cheapie 1.25" GSO barlow is great when I use it in my f/4 Newtonian, but the image is poor when I use my 2" GSO ED barlow (both 2X).
There are some very good eyepieces suggested by others. But I wouldn't suggest you buy one over another, ESPECIALLY for someone else. They will better served straight off getting simple plossls to get started, and then trying out other people's EPs at a star party. The process is longer, but the result is better. What someone finds comfortable and easy to use as an eyepiece varies greatly.
Filter wise, an OIII filter will be more useful for viewing from the big smoke than an UHC type. A UHC is just too narrow in bandwidth transmission for the best results in urban areas. It will work, but an OIII is brighter image wise and with the number of stars it will show. What you can do with 1.25" OIII filter is also make yourself a "blinking paddle" that you use to blink out tiny planetary nebulae so they reveal themselves from their surrounds. While DSO viewing in the city is always second best, blinking for PN's is actually something that's very effective. I've been successful in chasing some of the tiny PN's in the cluster M7 from my home in Sydney. I've attached a pic of my blinking paddle. It's just a piece of MDF that I can screw into a 1.25" OIII filter. I then flick the filter between my eye and the EP. It is very effective and I'd say pretty much the only way to find small planetary nebulae that quite literally are invisible without a filter. With a blinking paddle, these invisible planetary nebulae quite literally "POP" out. Oh, and an OIII filter is better for PN's than an UHC filter.
Mental.
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Thanks a lot Mental
Barlows look like they could be a bit iffy and just add extra weight so I think I'll stay away from them.
Cost not being much of a problem, (he's the CEO of some company) I was sort of thinking that the ES EP's might be a good starting option?
What you say about the filters is interesting, I might have to start looking into getting one myself. Do they make much difference if you've got dark skies? I was obsurving vail nebula the other night with my 6 inch newt and wondered what it would be like with a filter.
Cheers
Jo