Beginner: Panoptic 19 and 35mm in C11 plans

[kirkster501]

Hello despite all the reading I am doing about EP's I keep coming back to these TV Pan EP's for a new C11 I am going to get. I will get the WO 2" diagonal as well.

It just seems everyone raves about these Ep's. So, despite their considerable cost I feel I might pull the trigger on these - buy the best from day one so to speak. They will last a lifetime and be workable with potential future and faster scopes. I get some bonus in January as well Only live once.

Now I know there is a gap at the bottom end (high magnification) and I will fill that after my bank balance recovers (Nagler 13mm perhaps?). But I get 19mm = x147 and 35mm = x80. I might get a 40 SW Aero (x70) as well to kick start me at the really low mag end.. Woudl I need that Aero? Is it too close to the 35mm?

What FOV would I get out of the C11 with these EP's? I don't know how to work it out...

Is my reasoning sound? Might get a PAn 27 as well at soem point.

Thanks everyone for your ongoing patience with me and my bozo questions !

Rgds, Steve

[Alma]

There's an eyepiece calculator on the Televue website, which is very useful. That shows with a 280mm objective and f/10 focal ratio you'll get 0.79 degree true field with the 35mm and 0.44 degree with the 19mm. I've never used a 35mm Pan but the 19mm is superb - I have 2 for my binoviewer and they're brilliant in that role. With the 27mm you will get 0.62 degree tfov.

I also think the 24mm Panoptic is a superb eyepiece in SCT's, or any scope for that matter.

Alan

[John]

The Tele Vue eyepieces are excellent and will give a lifetime of performance in a wide range of scopes. You need to do your research and some maths though before you decide which to buy, for example the Nagler 13mm will show as nearly much sky as the Panoptic 19mm so could render the latter redundant !

If you divide the apparent field of view of the eyepiece by the magnification it gives in the scope you get the true field of view that it will give. As Alan says the 19mm Panoptic gives a .44 degrees true field at 147x wheras the 13mm Nagler will give a .38 degree true field at 215x. And, yes I think 40mm is too close to the 35mm.

A more balanced range might be:

40mm Aero (70x / 1 degree TFoV)

22mm Nagler (127X / .64 deg TFoV)

13mm Nagler (215x / .38 deg TFoV)

9mm Nagler (311x / .26 deg TF0V)

Or something along those lines !

[kirkster501]

Ok Guys, so do you think the Panoptic 35 mm and a Nagler 17 mm would do the trick? This looks a good combo from the Televue calculator.

That leaves the wide and mid field pretty much covered. I'd need something for high maginfication as well - but that will have to wait for a couple of months.

Or maybe the 35mm Pan and the 13 Nagler? That leaves a bit of a gap in the middle.... But teh 13 would be good for planetary and lunar which is my main interest.

I just like the idea of the TV's. I'd rather get two TV's now and buy more later.

Appreciate youtr thoughts please?

Steve

[John]

That sounds good. To be the devils advocate, your could get a 17mm Ethos for £50 less and have the very best there is

It shows nearly as much sky as the 35mm Pan does ! (Edit: ignore this - I got my maths wrong ! - the 35m shows more sky than the E17 )

Back to normality - I reckon the 35mm Pan and the 17mm type 4 Nagler would be an excellent setup

I have short focal length scopes so it's difficult to get used to the concept of lowest magnification being 80x

[Mark at Beaufort]

Hello Steve

Because the C11 has a long focal length I think I would buy a reducer to make the scope a f6.3 to give you more choices. First Light Optics - Celestron f6.3 Focal Reducer

I think I would agree with John that the 40mm Aero could be more useful on a scope with 2800 FL. I must say that I have had the 35mm Panoptic and it was a brilliant lens but I sold it to buy the 26mm Nagler.

I know some people buy lots of EPs but in the end I reduced my useable kit to just 5.

Personally with a C11 I would buy the 40mm Aero and a Reducer and then possibly two other EPs. The 40mm would give 70x and with reducer 44x. I would not go above 9mm because the mag would only be used on the rare occasions. A reducer would bring that mag down from 311x to 196x. A 17mm Nagler would give you 165x and with the reducer 104x.

The FOV with the 40mm Aero is 58.3' and with reducer 92.5'

However, someone with the C11 make give you more first hand knowledge.

Mark

[Chris H]

That sounds good. To be the devils advocate, your could get a 17mm Ethos for £50 less and have the very best there is

It shows nearly as much sky as the 35mm Pan does ! (Edit: ignore this - I got my maths wrong ! - the 35m shows more sky than the E17

Your not that far off, the 17E will show 0.61 degrees to the 0.79 of the 35 Panoptic. However the 21E will show 0.74 so that not far off at all.