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FlashDrive
08-04-2016, 10:28 AM
Having my first ' long focal ' telescope, what eyepieces ( focal length ) will be ' best ' to use with it.

Comfortable ' eye relief ' would be a bonus....

Scope is 80mm f/15 ..... obviously a ' Planetary ' Scope

Thanks in advance for your suggestions

Col...:)

MortonH
08-04-2016, 12:44 PM
Your 30mm Paragon will give you a 2mm exit pupil, 40x mag and around 1.7° fov. Should be nice on deep sky objects.

janoskiss
08-04-2016, 08:10 PM
f/15: wow!! That's one long scope! From your signature it looks like you have a good enough selection of EPs to try in it and see what works best and take it from there.

Besides a long FL widefield, for a scope like that I'd probably want a couple of orthos in the range of 10-20mm.

AEAJR
09-04-2016, 01:07 AM
Do you have a budget for these eyepieces?

Are you looking for planets, DSOs?

High mag? Wide views?

I see you have 30, 40 and 42 mm so I presume you are looking for something shorter.

I don't know if Explore Scientific is available where you are. In the USA all the distributors have them on sale. These are 82 degree 1.25 and 2" eyepieces, about 25% off I think.

FlashDrive
09-04-2016, 11:32 AM
I have suggestions on orthos which I have...only a 20mm & 25mm...

I have a Meade Research Grade 20mm @66* fov ....

An early Japanese 18mm smoothie....

A WO 15mm @72* fov...

I don't have a tracking mount, so ' high ' mag will be tricky to keep the ' object ' in field of view.

I guess I can experiment and also purchase a TV Delite.

May even look at the Baader Morpheus ... they look real nice.

Col....

SkyWatch
09-04-2016, 12:07 PM
What about the Vixen SLV 10mm that is in the classies at the moment?
- and Takahashi LE's are certainly worth a look.

- Dean

MattT
09-04-2016, 01:33 PM
The Baader Morpheus 14mm I have is REAL nice. Got so much going for it. For starters....price, weight, dual 1.25-2" barrel. Then there is the huge eyelens and the real easy view...no blackouts, no kidney beaning. The only downside I can say is the eyecup is rubbish....but as I always fold eyecups down that's a non issue for me....get one Col, actually get two ....buy the 9 as well and use a 2x barlow, should cover all sorts of viewing at f15.

Just looked at the photo of the scope....nice 2" Moonlite I see. In that case get an ES 30mm 82º before the ES sale ends. You'll have to add a nice sliding counterweight on the tube too....just gets better and better :-)

FlashDrive
09-04-2016, 02:10 PM
Morpheus are certainly on my list.... been reviewing them on WEB.
Excellent quality and the spec's are great ... especially the eye relief.

I see Agena Astro is selling them .....

Where am I going to get a ' sliding ' counter weight ' and bar from....??

Col.....

Camelopardalis
10-04-2016, 03:45 PM
For f/15, I'm not sure it's going to matter :lol:

Just something with low glare and good contrast if you're chasing planets...

Merlin66
10-04-2016, 04:34 PM
When I started out many, many years ago the best eyepiece around that a young apprentice could afford was a Ramsden(!!) - the UO Orthos were well beyond my reach!
An ol' timer I knew gave me the great advice" Son, at f15 even the bottom of a Coke bottle would give good views - use what you've got."

Re sliding weights - you can get fancy or just use a wrist training weight velcro bag wrapped around the end of the tube....

Don Pensack
15-04-2016, 08:07 AM
I would recommend something in the 40-80mm range for a low power eyepiece (it would be 2", of course).
If 1.25", stick with 35mm and shorter for low power, since otherwise the apparent field will be excessively narrow.

On the high end, 15mm to as short as 7.5mm will occasionally be useful, though you'll find eyepieces with exit pupils that small will exacerbate the problem with floaters in the eye, especially if used on the Moon at those powers.

I would bet a good 12mm would get a lot of use.

The 80mm aperture does constrain the scope in terms of magnification.
It's reasonable to think of 150x as about the maximum for this scope. Fortunately, that's high enough to see details on Jupiter and Saturn, though Mars might appear a bit small except around opposition this May.
Details on Mercury, Uranus, and Neptune are the province of large scopes.

If you'd like a list of all available eyepieces, download my 2016 Buyer's Guide to Eyepieces Here:
http://www.cloudynights.com/topic/532891-2016-eyepiece-buyers-guide/
Prices are in US dollars at current exchange rates.

Tropo-Bob
16-04-2016, 11:10 AM
Col, a 13 mm Nagler would give good views of the planets, and a crisp wide field of view for stellar objects and the Moon. At 92X, the exit pupil would be 0.86mm and the actual field of view would be similar in degrees! (This oddity is because the lens in mm is about the same at the apparent view of view of a Nagler in degrees.)

The 13mm from memory is also the lightest Nagler so is the least likely to upset the balance of the scope.

Other options: 11m Nagler, or any plossl or Ortho in the 11mm to 15mm range.

U could also buy a 6 to 9mm Ortho if you wish to split close double stars and really push limits on viewing planets.

A 30 to 35mm plossl is all you need for widefield viewing. It may be best to burrow and try widefield EPs first, as the baffle(s) in the scope may restrict the field to a less usage proportion.

ab1963
16-04-2016, 11:50 AM
I have to second the emotion on the 13 nagler type 6 Flash ,would suit

FlashDrive
16-04-2016, 12:31 PM
Thanks everybody ... some good advice given all round.
Still waiting for my ' OTA Rings ' from Peter Tan ...still haven't used the Scope yet....all I can do is look at it for now. :sadeyes:

Col....:D

ausastronomer
16-04-2016, 03:39 PM
Hi Col,

As Don Pensack mentioned the scope will be limited to about 150X to 160X because of its aperture. This is about 50X per inch of aperture.

From memory you already own a 12.5mm Docter? If so, you don't need anything else around this focal length. It's about the best eyepiece money can be at any focal length. You already have the longer focal lengths covered from 30mm to 42mm. What other eyepieces with a focal length < 30mm, besides the Docter, do you already have?

Cheers,
John B

FlashDrive
16-04-2016, 05:49 PM
John....

I have a 25mm Ortho

a 21mm Denkmeier

a 26mm TeleVue Smoothie

a Meade Research Grade 20mm @66* fov ....

An early Japanese 18mm smoothie....

a Vixen LV50mm

a Vixen 45mm 1.25 ' Black Top '

A WO 15mm @72* fov...

and some early Vixen ( Japanese ) smoothies....flat tops.

I'm pretty much covered I think.... although I'd like to try those Baader Morpheus

Col.....

Wavytone
16-04-2016, 10:00 PM
Col you have quite a mixed bag there but you've covered the range of focal lengths well enough - 10 or 12 will be as short as you'll ever use, through to the big LV50mm.

Don Pensack
16-04-2016, 11:41 PM
Good thinking about wider fields. Obviously, tracking at higher powers is a lot easier when the eyepieces have wider fields, since the objects stay in the field a lot longer during the drift.
If you need glasses while observing, look for eyepieces (like the Baader) that have eye reliefs of 17-20mm or more.

Just as an aside, no widefield eyepiece can be orthoscopic (free from distortion). Orthoscopy is limited to narrow fields (say 45° or less). So your Paragons are not orthoscopic, as good as they are.

MattT
17-04-2016, 05:37 PM
Hey Poppy,

Since my last post I now have the Morpheus 9mm too. Gonna give that and the 14 a good going over with my 10" Newt tonight and see how they perform. So far in long FL Fracs they are perfecto. Barlwed they are also perfecto. I was going to go Delos but the price stopped me dead in my tracks...the M's are AUS$200 cheaper.....each :shrug:

Other eyepieces I own and love in long FL Fracs...ES 40 34 28 24 and 20 68º :D

The only TV eyepieces I own are the 27 and 19 Pans....a bit better colour and slightly sharper stars...great in short FL scopes, like your 'ol Sharpstar ED 60 but the returns diminish in long FL Frac's...IMO

FlashDrive
17-04-2016, 08:46 PM
I'll give a shot at what I have here ( eyepieces ) and then decide what's good...better or best.

I'm still want to purchase a Baader Morpheus 14mm in the not to distant future...they have a nice size ' eye lens ' and good eye relief ...I may even buy the 17.3mm when it shows up in the shops.....Apparently there is a delay on those reaching the shelves at the moment.

Flash ......

janoskiss
17-04-2016, 08:52 PM
You're just looking for an excuse to buy new toys! :P (not that there is anything wrong with that. ;))

FlashDrive
21-04-2016, 08:35 PM
Update .... email from Peter Tan today .... Ring Set is on its way with ' Tracking ' Details.

:rundog: .... make it snappy Mr Postie.

Col....:D

Don Pensack
29-04-2016, 08:35 AM
I've thought about this a bit longer, and there are
too many choices to suggest specific eyepieces, but I do recommend the following focal lengths:
15mm (any), 30mm (wide or ultrawide), 55-56mm (Plossl--you'll love this one)
Maybe, you can add a 10mm for high power, and then use a 2X barlow to yield 7.5mm with the 15 and 5mm with the 10 if you go double star hunting or get exceptionally good seeing for lunar/planetary.

FlashDrive
29-04-2016, 01:17 PM
Don .... I have all those focal lengths you mention.....

I tried a Vixen LV50mm in the Scope on the front veranda, looking at trees in the far distance .... I hardly had to move the focuser and the 50 snapped into focus...wide field view filled the whole eyepiece with trees.

Come on clear weather....:D