Monster in the making

[alan potts]

Astrobits,

Sorry I have to disagree with you, I and many of the members often make reference to pupil size and exit pupli on a whole range of eyepieces as well as other things that effect the eye, floaters for example. I agree it is important this is one of the reasons that many of us consider it.

Please take the time to read through a few more posts I think you will find I am right.

Merry Christmas,

alan.

[John]

I try and include something on exit pupil size whenever relevant in my posts on long focal length eyepieces. Questions from folks thinking about using a 40mm or longer focal length eyepiece with F/5 scopes pop up reasonably frequently on here. I agree with you Nigel that it's important to keep the exit pupil an efficient size if you are going to make the most of the scopes aperture.

[alan potts]

John,

I whole heartedly agree you do. You are not on your own and many other members do the same when it is relevant to what we a talking about. It was of course you that introduced me to the floaters, now I look for them but no luck so far. Maybe I need a shorter eyepiece.

Alan.

[John]

.........It was of course you that introduced me to the floaters.......

That well known 1970's Motown group

[alan potts]

Nice one John, I wonder what happened to them, proablely still on the go and weigh 150 kgs each.

All joking aside I believe this was something you had a problem with on very short eyepieces, my shortest is a 4mm Radian, maybe not short enough and a lot of eye relief for the the problem to occur. After seeing the results with the 6mm and the 4.5mm Delos I was thinking of getting a 3.5mm, this would give me about x230 on my refractor which I think is enough. Now all I need is a snow plough and some type cloud clearing device.

It really gets up my nose, having newish gear and not being able to use it.

Alan.

[John]

It's pretty awful here too Alan, it thats any consolation. We don't have the snow though, yet anyway.

I find a 3.5mm OK although I can see a couple of floaters when I use it. I tried a 2.5mm Nagler for a while but that really highlighted the floaters, as well as producing too much power for any of my scopes. Sold that one quickly !

[alan potts]

John,

I seem to remember it was the 2.5mm that you said you had a problem with. I think this eyepiece would give too much magnification on any of my scopes, even the 70,, ED which has a F/L of 420mm. In any case it is a big spend for only one scope that I have pigbacked on my LX 200. I fI were to buy the 3.5mm it would be useable in the refractors and the Mac/Newt, I may wait and see if a secondhand Nagler comes up. It seems to be the case that when ever I pay out for a new eyepiece, three are on the market S/H the day after.

Your weather being bad is no consolation either, I wish you all had a clear sky, that is my Christmas wish to all of the members in the UK, it been a rough few months there.

Take care,

Alan.

[Dunkster]

Likewise Alan! Better luck for the New Year

I also echo Alan's sentiment, I hope everyone gets some quality time out under the stars over the Christmas period! I'm flying south to increase my chances but my thoughts will be with you all in cooler, more festive climes