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TwistedRider
31-07-2018, 06:34 PM
So I was trying to find an "Eyepieces 101" type guide with descriptions and explains of the main types of eyepieces.

I know there are lots (and lots), but looking for a good basic guide do I know what to potentially look at and what each type will or won't help me with.

Any suggestions

Thanks in advance :thumbsup:

m11
31-07-2018, 08:02 PM
Hi Twisted,

Eyepiece selection is quite a subjective topic depending on people's criteria and scope types.

Hopefully the below link helps. Apologies if you not supposed to repost other forums:
https://stargazerslounge.com/topic/234066-different-types-of-eyepieces-and-their-purpose/

Personally I have been acquiring Televue eyepieces - especially Ethos/Nagler/panoptics eyepieces. They are not cheap but I enjoy the view through these eyepieces. Also been collecting orthos eyepieces for the planets. :rofl:

Regards,

M11

morls
31-07-2018, 08:19 PM
That's a great link M11, thanks!

This might also be useful - the first section not so much, but the second section describes the construction of different types.

https://en.wikipedia.org/wiki/Eyepiece

m11
31-07-2018, 08:28 PM
Hey Moris,

Yep, good link on eyepiece designs you posted. :thumbsup:

Which eyepieces do you enjoy using with your scopes?

TwistedRider
31-07-2018, 11:02 PM
Thanks fellas.

Looks like I have some reading to do.
Already bought 1 extra which I seem to like so far

But these things aren't cheap . :eyepop: :rofl:

m11
01-08-2018, 11:47 AM
Hey Drew,

The good thing is that eyepieces you accumulate you keep along the way.

It depends on what you like and willing to pay for it. Genereally the wider the view(degrees like 82 and above) and the longer focal length eyepieces cost more.

If you can wait, i know from experience this is hard, you can get savings by buying second hand. Eyepieces do hold their value.

I reckon for myself, i have gotten value out of the eyepieces I have and I am happy. Trying different eyepieces is an expensive excercise :rofl:

M11

Atmos
01-08-2018, 04:58 PM
None of my eye pieces are wider than 60-68° and I don’t often feel like I’m missing out on anything. In a way I prefer the narrow FOV which is why almost all of my EP are plossls :)

astro744
01-08-2018, 06:02 PM
Similar question in another forum so similar answer here.

See

http://www.televue.com/engine/TV3b_page.asp?id=3

Specifically http://www.televue.com/engine/TV3b_page.asp?ID=2

and

http://www.televue.com/engine/TV3b_page.asp?id=154

Lots of good info at the last link.

I don't know what your budget is but the Tele Vue web site is full of great technical information and advice. I also recommend looking through as many eyepieces as you can at star parties preferably through a similar 'scope as your own as eyepieces perform differently in different 'scopes.

When I first looked through an original type 13mm Nagler I said to myself I must have one some day and it was nearly 20 years later before I finally got one. The same applied to a Tele Vue 24mm Widefield which works really well in any telescope. In fact all Tele Vue eyepieces work well in any telescope and you simply pick the focal length, apparent field and eye relief that suits you and your telescope.

When I first started though I did invest in some Clave Plossl which I still use often. There is a lot more to choose from now and it doesn't make it any easier.

Here is some more reading,

https://www.opticsplanet.com/howto/how-to-guide-telescope-eyepieces.html

and this one is quite good with links at the end,

https://www.handprint.com/ASTRO/ae5.html

SkyWatch
01-08-2018, 07:55 PM
Hi guys,

The Televue links from astro744 don't seem to work for me, so this may work:
http://televue.com/engine/TV3b_page.asp?id=154

Lots of good info on the Televue site.

Good luck,

Dean

astro744
01-08-2018, 10:00 PM
Thanks Dean. Links now fixed.

TwistedRider
02-08-2018, 08:14 PM
Thanks all,. Have a free day tomorrow, so shall be doing some quiet study ;)

Not in a rush to spend up big... Will try everything in sight at Star parties though until I find what I like :)

I wanted an idea of what they all do... Technically.

Starting to get my head around it.

ab1963
02-08-2018, 10:07 PM
I have owned many eyepieces bought and sold them and through stupidity have sold the Docter 12.5mm twice and bought it a third time to never be sold again,It is like having a top notch ortho with a 80+ fov and is the eyepiece I do most of my viewing through ,Expensive it might be but the best on all counts it definitely is and worth every cent.......

yoda776
30-09-2018, 04:28 PM
I have found the 'Choosing and using Astonomical eyepieces' by william Paolini in the Patrick Moore Practical Astronomy series provides some good info across the board. Not saying it is definitive but may provide some information you may find useful.

Don Pensack
03-10-2018, 09:14 AM
This might help:
http://www.scopecity.com/optics-course-0025.cfm?pn=EYEPIECES+TYPES+AND+COA TING+INFORMATION

and this might tell you what's available today:
https://www.cloudynights.com/topic/612955-2018-eyepiece-buyers-guide/

Wavytone
03-10-2018, 01:27 PM
Drew, strongly suggest you try some before buying.

Evolution of eyepieces http://www.brayebrookobservatory.org/BrayObsWebSite/BOOKS/EVOLUTIONofEYEPIECES.pdf

Depending on the type of telescope you have the image plane is curved, possibly convex or concave - see https://www.telescope-optics.net/curvature.htm

You should choose eyepieces that suit the curvature of the image plane, for example Plossls (despite their simplicity) are an excellent match for Newtonians.

Similarly most eyepieces from Televue - their primary market is the US where big dobs are the most popular.

Conversely Erfles and SWA eyepieces have a strongly curved field which suits smallish refractors, but do not suit newtonians.

Vixen eyepieces being japanese are intended primarily to suit the scopes popular there which are refractors and SCT's, hence theirs are good for that but again not so good in fast newtonians.

The next issues are the choice of focal length:

- Maximum eyepiece focal length is about 6mm x the focal ratio of your scope, eg for an f/5, 30mm eyepiece.
- Minumum eyepiece focal length is around 0.7mm x the focal ratio of your scope (newtonians and SCTs) or 0.5mm for refractors.

Lastly the actual field of view (set by the field stop diameter), and the tradeoff between large apparent field of view vs large eye-relief (you can have one, but not both simultaneously). These are up to you.

The_bluester
05-10-2018, 10:13 AM
Drew, given you are going to Snake Valley, I will have a few there that you can try, some 2" Explore Scientific 82 degree ones and some 1.25" Televue Plossl's.