10" dob f/4.7 (xt10i) - pls comment on my EP selection

[cevinator]

Hi guys,

A week ago I was contemplating between an SCT and dob for my first telescope. I went for a 10" dob eventually. I was even thinking to go for a 12" (mind you I didn't order anything yet) but am quite settled on the 10" for now, seems to be good aperture and reasonably portable which I like.

So apparently - and this wasn't really obvious at first - I picked quite a fast scope (f4.7), and they need quite a good selection of EPs, or so I've read on this forum. Luckily I still have an ok budget around 1200 € (obviously I don't have to spend it all, it's more than the scopes worth).

So please do comment and make suggestions on what I picked out. Keep in mind, I'm only in it for the views really, doesn't matter what it is, I'd like the moon/planets/dso, anything really. I did alot of reading on EP's and it was quite obvious that everything from TeleVue is really the bomb. Quality comes at a price I guess because those things aren't cheap. I also noticed alot of people like the ES EP's (90% of the quality and half the price?). I was also thinking about the nirvana series but at last I decided I wanted everything (except barlow) from one brand. Not sure why, though... If you have other decent suggestions pls let me know!

This is what I picked out: 

ES 82° Series™ - 11mm - 1.25"

ES 82° Series™ - 8.8mm - 1.25"

Tele Vue 2x Barlow - 1.25" - achromatic

ES 68° Series™ - 28mm - 2"

ES 82° Series™ - 18mm - 2"

Apparently for lower mags I couldn't get 1.25" EP's so I can't barlow them. Magnifications I have now: 42.8x, 66.6x, 109.1x, 136,4x 218.2x, 272.7x.

Am I missing something here? I also picked alot of wide angle lenses... Is there any reason to go for small angle lenses? I was thinking: the more I can see, the better. Maybe this logic is flawed?

[LeeB]

I use a similar scope 250mm F4.8, The range of mags that give your eye the best/accruity (definition) are when the exit pupil sits between 2 and 3mm , for your scope thats 83x to 125x , so always get an eyepiece that sits at each end of this range, then a wide angle low mag is a good hunter and observer for wide objects (aim for 6.5mm exit pupil x38), finally get a couple of higher mags but the limit in perfect seeing is really 250-400 with the scope you have, (exit pupil 1mm - 0.6mm) .

In summary I would go for wide field 2inch 30mm-32mm , 20-15mm 1.25, 14-15mm wide 1.25,  9-10 mm and a 6mm & 4mm with good eye relief (for high power planetary) even then  the 4 won't get much use.) 

[faulksy]

if i had your budget and knowing what i no now, i would buy a 13mm ethos this will cover most bases and you will never need to upgrade it, or 2 naglers something like a 10mm and 22mm

[rwilkey]

Hi Cevinator, you wouldn't want to Barlow low mag ep's, there's no point as you defeat the object of having them in the first place.  I am a big fan of the ES82 series and therefore think your choices are excellent and well considered.  As long as you don't wear glasses, as the eye relief is a bit tight.

[cevinator]

Thanks everybody!

I use a similar scope 250mm F4.8, The range of mags that give your eye the best/accruity (definition) are when the exit pupil sits between 2 and 3mm , for your scope thats 83x to 125x , so always get an eyepiece that sits at each end of this range, then a wide angle low mag is a good hunter and observer for wide objects (aim for 6.5mm exit pupil x38), finally get a couple of higher mags but the limit in perfect seeing is really 250-400 with the scope you have, (exit pupil 1mm - 0.6mm) .

In summary I would go for wide field 2inch 30mm-32mm , 20-15mm 1.25, 14-15mm wide 1.25,  9-10 mm and a 6mm & 4mm with good eye relief (for high power planetary) even then  the 4 won't get much use.) 

I think my selection more or less covers what you mention. I might take another look to fit the ideal exit pupil range a little better. Thanks!

if i had your budget and knowing what i no now, i would buy a 13mm ethos this will cover most bases and you will never need to upgrade it, or 2 naglers something like a 10mm and 22mm

To be honest, these kind of 100° EPs didn't catch my attention until now. I do like the idea that such an EP is a substitute for many smaller EPS (less changing EPs is always good). Most of what I read about them does sound very promising as well. Still not everybody is as happy with them apparently, although the quality of the viewing is not up for discussion, I've read more than once that the view is just a little bit too much to take in all at once, while other people can't stop raving about them. Honestly, I don't know in which category I'll fit and I probably won't have the chance to test it somewhere. So I'll have to buy one to find out but I think the price is just too high for that kind of risk... I just don't know if I'll fit into the super wide angle category... I think I might, whats wrong with seeing more? But I can't be sure though...

Hi Cevinator, you wouldn't want to Barlow low mag ep's, there's no point as you defeat the object of having them in the first place.  I am a big fan of the ES82 series and therefore think your choices are excellent and well considered.  As long as you don't wear glasses, as the eye relief is a bit tight.

Thank you. This does make me wonder about my choices a little bit. I was always thinking that my scope won't last forever but my EPs hopefully would. I'm thinking really long term here now, but when getting older I think the chance is pretty big that I will wear some glasses some day... As long as there is enough resell value, maybe it's not that much of a problem...

[rwilkey]

He Cervinator, don't let getting older stop you, I never worry about that.  Do what's best for now, you can't worry about what might be!