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Eyepieces
Discuss telescope eyepieces.

Topics: 161

Last post: Re: Best 7mm, 6mm, 5mm, and 4… by Bigzmey, Thu Apr 15, 2021 11:35 pm

161 Topics

1780 Posts

Last post Re: Best 7mm, 6mm, 5mm, and 4…
by Bigzmey View the latest post
Thu Apr 15, 2021 11:35 pm
Binoculars
Discuss binoculars.

Topics: 106

Last post: Re: Optica 11 x 80's by helicon, Sun Mar 21, 2021 6:59 pm

106 Topics

1143 Posts

Last post Re: Optica 11 x 80's
by helicon View the latest post
Sun Mar 21, 2021 6:59 pm
General Optics
Discussion of optical systems and their characteristics.

Topics: 7

Last post: Re: Finally it looks as if my… by Greenman, Wed Apr 14, 2021 10:18 pm

7 Topics

77 Posts

Last post Re: Finally it looks as if my…
by Greenman View the latest post
Wed Apr 14, 2021 10:18 pm

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Last post

A Guide to choosing eyepieces

Last post by notFritzArgelander « Sat Nov 14, 2020 3:08 am
Replies: 9
by OleCuss » Sat Apr 27, 2019 4:40 am

First post

There is much controversy over eyepieces and their selection and this will persist for eternity. The reason for this is that each of us has a...

Last post

Awesome write-up 👍

Thanks, said the guy with a box of cheap old Plossls.

I have a bag of cheapish new Plossls. The Vixen NPLs perform very well...

9 Replies

10100 Views

Last post by notFritzArgelander
Sat Nov 14, 2020 3:08 am
Creating a basic set of eyepieces for your new telescope

Last post by tomthetank « Fri Oct 09, 2020 2:51 am
Replies: 65
by Lady Fraktor » Thu May 23, 2019 2:34 am
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First post

One of the most asked questions by beginners, What eyepieces should I get?

There is always a lot of discussion from people on what eyepieces to get...

Last post

thank you
65 Replies

20780 Views

Last post by tomthetank
Fri Oct 09, 2020 2:51 am
Evolution of Eyepieces by Chris Lord

Last post by Piet Le Roux « Fri May 22, 2020 9:43 am
Replies: 12
by notFritzArgelander » Sun Oct 27, 2019 2:36 am

First post

I just brought this over from the old place. I suggest we make this sticky?

Last post

PS the Metcalf telescope, depicted on our club badge, were used to take photographic plates for Harvard University at Boyden, it is still being...

12 Replies

10861 Views

Last post by Piet Le Roux
Fri May 22, 2020 9:43 am
Best 7mm, 6mm, 5mm, and 4mm Eyepieces for the Moon

Last post by Bigzmey « Thu Apr 15, 2021 11:35 pm
Replies: 20
by Refractordude » Wed Mar 24, 2021 12:25 am
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First post

Was out last night with my scope giving me 300 magnification on the Moon. The AgenaAstro zoom eyepiece I have is super sharp. However, it does not...

Last post

Hi,
You don't mention which telescope you are using. This makes quite a difference. I note that in your signature, all your telescopes are long f...
20 Replies

493 Views

Last post by Bigzmey
Thu Apr 15, 2021 11:35 pm
Finally it looks as if my Antares Versascope will guide.

Last post by Greenman « Wed Apr 14, 2021 10:18 pm
Replies: 1
by Greenman » Wed Apr 14, 2021 1:05 pm

First post

My I have had some fun with this - very little information on the back focus needed to use this as a guide scope with an astro camera, in my case an...

Last post

Whoops M51, guide scope will focus but too far out of alignment, never mind goo PA and getting good 1min subs.

1 Replies

27 Views

Last post by Greenman
Wed Apr 14, 2021 10:18 pm
Aperture size and "seeing" conditions

Last post by Bigzmey « Tue Apr 13, 2021 7:08 pm
Replies: 36
by Piet Le Roux » Wed Sep 30, 2020 2:13 pm
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First post

I am placing this in Off Topic because I just realise we don't have a General Observing sub forum!
I have come across this notion, in different...

Last post

Thanks for all the different viewpoints, advice and information, unlike some members I don't perceive that as disrespectful. At this stage I am not...
36 Replies

2309 Views

Last post by Bigzmey
Tue Apr 13, 2021 7:08 pm
Pentax XWs are on sale now

Last post by Bigzmey « Fri Apr 09, 2021 8:49 pm
Replies: 12
by Bigzmey » Mon Mar 08, 2021 5:07 pm

12 Replies

459 Views

Last post by Bigzmey
Fri Apr 09, 2021 8:49 pm
Zeiss eyepiece nomenclature ?

Last post by j.gardavsky « Fri Apr 09, 2021 6:26 pm
Replies: 12
by StarBru » Wed Apr 07, 2021 9:36 pm

First post

I'm interested in buying a few Carl Zeiss Jena microscope eyepieces to use with my 60mm telescopes using .965 accessories. I don't understand how to...

Last post

... I cannot afford the most expensive microscope eyepieces, but maybe I'll get lucky finding the less expensive CZJ K versions.

Hello Bruce,

the...

12 Replies

178 Views

Last post by j.gardavsky
Fri Apr 09, 2021 6:26 pm
Difraction Rings

Last post by Bigzmey « Mon Apr 05, 2021 4:50 pm
Replies: 1
by Jones » Mon Apr 05, 2021 5:19 am

First post

Why does my 6 f6 GSO newt show a prominent 1st difraction ring,
while the Edmund 6 f8 reveals just a faint one?

Neither could see the 'f' star in...

Last post

I believe it has to do with F-ratio and size of the central obstruction. The larger central obstruction the more light is distributed from the airy...

1 Replies

90 Views

Last post by Bigzmey
Mon Apr 05, 2021 4:50 pm
Any ES 52 deg Eyepiece Experience Yet?

Last post by MistrBadgr « Sat Apr 03, 2021 11:43 pm
Replies: 23
by MistrBadgr » Sun Jan 24, 2021 6:04 pm
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First post

I am considering some of the shorter focal length ES 52 degree eyepieces for use with my f/5 reflectors. One specific application is with the 3mm...

Last post

I received notice today, April 3rd, that an ES 52 4.5mm eyepiece is being shipped to me. I had one on back order with the expectation that it would...
23 Replies

944 Views

Last post by MistrBadgr
Sat Apr 03, 2021 11:43 pm
How to Calculate the Limits of Your Telescope

Last post by MistrBadgr « Thu Apr 01, 2021 5:16 pm
Replies: 6
by mikemarotta » Tue Mar 16, 2021 10:20 pm

First post

Resolving power (Rayleigh limit) = 138/D arc seconds
Resolving power (Dawes limit) = 116/D arc seconds
Theoretical visual limiting magnitude...

Last post

... Mind you, he was using 3.5 and 7 Questars which are arguably as good as you can get! It does agree pretty much with my personal observations...

6 Replies

311 Views

Last post by MistrBadgr
Thu Apr 01, 2021 5:16 pm
80 and 85mm Plossls

Last post by DeanD « Thu Apr 01, 2021 1:16 am
Replies: 23
by Bigzmey » Wed Mar 24, 2021 9:37 pm
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First post

Just saw 80mm and 85mm 2 Plossls on sale on Astromart. You don't see those every day.

Something to consider if you own a scope slower than F11...

Last post

Well, it is April 1st after all... :dance:
23 Replies

429 Views

Last post by DeanD
Thu Apr 01, 2021 1:16 am
ES 62 deg EPs experience

Last post by 10538 « Wed Mar 31, 2021 11:35 am
Replies: 2
by Bigzmey » Tue Mar 30, 2021 7:59 pm

First post

I was looking for binoviewer-friendly wide field EPs in 25mm range. I have ES68 24mm, which is a very nice EP, but too fat for BV. APM UFF 24mm is...

Last post

Hi Bigz! I’m looking forward to hearing how the 26mm works out for you. I have a 24 Panoptic but I’m still in the learning curve with my WO’s so I’m...

2 Replies

101 Views

Last post by 10538
Wed Mar 31, 2021 11:35 am
Selected ES EPs are on sale

Last post by MistrBadgr « Mon Mar 29, 2021 10:35 pm
Replies: 2
by Bigzmey » Sun Mar 28, 2021 4:05 pm

2 Replies

132 Views

Last post by MistrBadgr
Mon Mar 29, 2021 10:35 pm
New Meade EP 82 and 60 FOV lines

Last post by Bigzmey « Wed Mar 24, 2021 3:24 am
Replies: 8
by Bigzmey » Fri Jan 08, 2021 12:34 am

First post

Meade has released new 82 and 60 deg FOV lines to replace their older UWA and HD60 series.

I am a big fan of UWA and HD60, let's hope that the...

Last post

I agree with Refractordude that Meade UHD and released at the same time Celestron Ultima Edge seem to be rebrands of APM UFFs. Orion and Altair offer...

8 Replies

579 Views

Last post by Bigzmey
Wed Mar 24, 2021 3:24 am
The Pretoria 28mm

Last post by Piet Le Roux « Tue Mar 23, 2021 4:36 am
Replies: 6
by Piet Le Roux » Mon Mar 22, 2021 8:45 am

First post

This eyepiece was designed by two South Africans, in Pretoria, in the mid 80's because fast paraboloids with Dobsonian mounts were becoming popuar...

Last post

Yes its sad...but the thing is that I am passing 60 this year and I don't know for how long I can still handle the 27Kg mirror box....I would have...

6 Replies

190 Views

Last post by Piet Le Roux
Tue Mar 23, 2021 4:36 am
Optica 11 x 80's

Last post by helicon « Sun Mar 21, 2021 6:59 pm
Replies: 7
by AstroBee » Fri Feb 19, 2021 3:01 am

First post

Any idea what these are worth? I was gifted these a while back and have never been able to find anything about them. They are very old as you can...

Last post

I forgot to mention they also had a mail order business and advertised in Astronomy Magazine back in the day.

7 Replies

470 Views

Last post by helicon
Sun Mar 21, 2021 6:59 pm
EPs for binoviewing

Last post by Ruud « Sun Mar 21, 2021 1:54 pm
Replies: 3
by Bigzmey » Sat Mar 20, 2021 3:02 am

First post

I have recently picked a used basic Orion binoviewer. Still waiting for a clear night to give it a shot. In the mean time was playing with my EP...

Last post

Morpheus eyepieces have plenty eye relief. I expect that if you use them with their winged eye cups their bulk would be far enough from your face to...

3 Replies

124 Views

Last post by Ruud
Sun Mar 21, 2021 1:54 pm
What Are Your Future Eyepiece Plans, And Are You Addicted To Buying Eyepieces?

Last post by Starship9 « Mon Mar 15, 2021 5:09 pm
Replies: 40
by Refractordude » Mon Feb 15, 2021 10:04 pm
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First post

I am addicted to buying eyepieces, but out of a curiosity on how eyepieces compare against each other. I have compared all the low budget eyepieces...

Last post

I'm glad that I don't get on with binoviewing !

I was lucky that a UK dealer loaned me many eyepieces over a period of time so I got to try a lot...
40 Replies

1188 Views

Last post by Starship9
Mon Mar 15, 2021 5:09 pm
APM UFF eyepieces on sale

Last post by pakarinen « Mon Mar 15, 2021 1:04 pm
Replies: 3
by Lady Fraktor » Mon Mar 08, 2021 6:49 pm

First post

Eyepieceetc has the entire APM UFF line on for substantial savings.

Last post

I see these APMs are listed as Not glasses compatible . Is that accurate? Looks like there's enough eye relief.

3 Replies

136 Views

Last post by pakarinen
Mon Mar 15, 2021 1:04 pm
What Are K9 Vs K7 And Bak4 Prism Binoculars?

Last post by j.gardavsky « Sun Mar 14, 2021 7:13 pm
Replies: 3
by Refractordude » Sat Dec 19, 2020 3:51 am

First post

Came across K9 for the first time. How do K9 compare against other types of glass/coatings used for binoculars? Thanks all.

Last post

Came across K9 for the first time. How do K9 compare against other types of glass/coatings used for binoculars? Thanks all.

K9 is the CDGM China...

3 Replies

517 Views

Last post by j.gardavsky
Sun Mar 14, 2021 7:13 pm
Ordered Orion Giantview 15x70s

Last post by StarBru « Sun Mar 07, 2021 3:43 pm
Replies: 9
by pakarinen » Thu Feb 18, 2021 3:48 pm

First post

Pulled the trigger on a pair to replace my Celestron Skymasters. I had a couple of AMZ gift cards so I figured, why not. One thing I like is they're...

Last post

Congrats on the new Orion Giantview 15x70's!

9 Replies

666 Views

Last post by StarBru
Sun Mar 07, 2021 3:43 pm
Focus on Simon Ploessl

Last post by j.gardavsky « Sun Feb 21, 2021 8:24 pm
Replies: 19
by mikemarotta » Wed Dec 16, 2020 6:47 pm

First post

(An earlier version appeared in the December 2020 issue of Sidereal Times newsletter of the Austin Astronomical Society.

The Ploessl ocular...

Last post

Hello Michael,

very interesting!
Your times with GM, have it been the geometry measurement systems for the body in white manufacturing?

Best...

19 Replies

938 Views

Last post by j.gardavsky
Sun Feb 21, 2021 8:24 pm
Fujinon FMTR-SX 10x50

Last post by DeanD « Fri Feb 19, 2021 6:15 am
Replies: 4
by DeanD » Mon Feb 15, 2021 7:02 am

First post

I couldn't resist: a pair of these came up barely used and for a good price...

My old 10x50's are the HG Series Chinese-made ( ). These are quite...

Last post

Congrats on the new glass Dean! My wife would be happy if I buy more binos as long as I don't buy more scopes. :lol:

I guess that would depend on...

4 Replies

308 Views

Last post by DeanD
Fri Feb 19, 2021 6:15 am
TV Delites

Last post by starfield « Sun Feb 14, 2021 12:45 am
Replies: 18
by John Fitzgerald » Tue Feb 09, 2021 2:17 am

First post

To those who have one or more, what do you think of the Delites vs other eyepieces?

I have recently acquired a 5mm Delite, and plan to do a...

Last post

I have one 7mm that I use with my Dob. Really like it. Really sharp and comfortable to look thru The wider field is handy on a Dob if you don't have...

18 Replies

504 Views

Last post by starfield
Sun Feb 14, 2021 12:45 am

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