Televue eyepiece advice please

[philipheaven (Philip)]

Hello everyone,
I’m seeking some input on eyepiece purchases I’m considering. My telescope is an 8 inch f/5 reflector on an eq5 mount. My current eyepieces are all Plossls - a 25mm, a 10mm and a 6.3mm, as well as a Televue 2x Barlow. I enjoy both deep space and planetary viewing. I also appreciate decent eye relief (I’m sick and tired of peering through tiny Plossl eyepieces!).

I’ve decided to finally take the step and start a Televue eyepiece collection. I’m attracted to the quality of Televue (I was stunned at the quality of my Televue Barlow), as well as the ability to expand my field of view while at the same time increasing magnification.

Obviously with Televue being such outstanding pieces of equipment they are very expensive. I’ve also taken on the advice that every eyepiece collection should be well planned out and considered. In saying that, I can only purchase three eyepieces to start. With those initial three eyepieces I want to be able to cover a range of magnifications, as well as fields of view, until I can afford to expand my collection and ‘fill in the gaps.’ I’ve decided I can’t afford Ethos at the moment.

I’ve come up with the following three eyepieces to start. I’ve included their apparent field of view, the magnification they would yield, as well as the field of view they would yield in my telescope. I would also be using my Televue Barlow (I will need a 2 inch Barlow for the 17mm).


Nagler 17mm 82°AFV 58.8x 1.39°FOV

Nagler 12mm 82°AFV 83.3x 0.98°FOV

Delos 8mm 72°AFV 125x 0.57°FOV


Does that seem like a good place to start until I can afford more eyepieces? A good range of magnifications and fields of view? Any other recommendations?

[barx1963 (Malcolm)]

Phillip

That is not a bad selection. Powers are 59x, 83x and 125x and using a barlow you get 118x, 166x and 250x. As the 17mm barlowed would give similar power to the 8mm unbarlowed, a 2" barlow id probably unnecessary.

I am a believer in have a low power EP that gives a nice 4mm exit pupil for at least one EP in a collection. The 17mm will give you 3.4mm which is pretty close.

Also I note you have gone the 12mm which gives better eye relief than the popular 13mm T6.

Overall a good choice.

Malcolm

[philipheaven (Philip)]

Yep I went for the 12mm due to the eye relief. Do you think the 12mm is still a good choice over the 13mm nagler?

Thanks for the advice Malcolm. I had some doubts about the need for a barlow on the 17mm - think I will put the money towards a 4th eyepiece.

If you were going to add a fourth eyepiece to those three what would it be? Lower magnification and bigger FOV? (Like a 22mm nagler?) or the opposite end of the spectrum, like a 6mm Delos?

[barx1963 (Malcolm)]

Phillip
The main advantage of the 13 over the 12 is size, The 13 is not much larger than a 25mm plossl, so is a lovely lightweight high end EP.
Personally, I think 3 EPS is enough. I have 5, but really only 3 on any regular basis. If I was going to add one I would think about wider. In an 8" 125x is starting to push it. I found the 6mm Delos quite hard to use in my 12", mind you I find I have little patience for high power observing.


Malcolm

[Allan]

G'day Philip. Every eyepiece I have ever looked through with the green band running around it has been superb. So you are on the right track.

The Delos is a great eyepiece and you won't do better than buy the 8mm. You could even add the 6mm later for more magnification.

The thing that strikes me about Naglers is how comfortable they are to use. I was lucky to observe through the 12 and 17 just recently and they were really nice. So again I'm sure you will be happy with them. And it makes sense if you get those that the 22 will fit into that line up for a really wide, low power view.

That would be 5 eyepieces for a great set.

Now, lets talk about the Ethos. Are you sure you can't afford one?

[MortonH]

Hi Philip,

I also have an 8" F/5 Newtonian as my main scope. My sequence of eyepieces for deep sky observing (i.e. non-planetary) are:

22mm Panoptic
14mm Delos
10mm Pentax XW
8.8mm Explore Scientific

The magnification of the 22mm is a bit low so I'm looking to get something in the 17-19mm range.

I think the range of focal lengths you're suggesting would be very good in your scope, although you might find the 8mm gives a slightly dimmer image than you want. So an alternative sequence might be 17mm, 13mm, 9mm. To reduce cost and weight, I would recommend:

17.3mm Delos
13mm Nagler
9mm Nagler

If eye relief is an issue the Delos are great.

Oh, and try to buy them used on Ice in Space. You'll be able to afford at least one extra eyepiece with the money you save!

Morton

[philipheaven (Philip)]

Hi everyone, I very much appreciate all of your input.

Allan – afford Ethos? One day, but not just yet. I’ve got a few more decades of observing ahead of me (hopefully!), so if I went straight to the Ethos where would I go to afterwards? I can’t peak too early! I do like the idea of starting off with the Nagler as well. I’m worried if I went straight from Plossl AFV to an Ethos AFV I’d fall in through the eyepiece!

MalcolmH – I do like the idea of the 13mm Nagler but I think the eye relief of the 12mm appeals to me a bit more. I like the adjustable eye guard function as well. Plus the 12mm will provide me almost an extact 1 degree FOV (not much of reason but I enjoy the round number!).

I was also looking at the Panoptic as well (mainly 22mm). I’ve read nothing but outstanding reviews. The reason I think the 17mm Nagler will be a better option though is because it will provide almost the same size FOV plus increased magnification.

As for the higher weight of particular eyepieces – at what point does that become an issue?

[SingleMalt]

I'm not an expert, but when I started I decided that I wouldn't compromise with eyepieces in the beginning only to have to replace them later on. I went with a 13mm Ethos and was happy with that and my stock plossls till I could afford 21 & 8mm Ethos's... (Ethoi?)

At any rate, Tele Vue make great stuff, I'm sure you'll be happy with whatever you get.

[Shark Bait (Stu)]

Originally Posted by SingleMalt

I'm not an expert, but when I started I decided that I wouldn't compromise with eyepieces in the beginning only to have to replace them later on. I went with a 13mm Ethos and was happy with that and my stock plossls till I could afford 21 & 8mm Ethos's... (Ethoi?)

At any rate, Tele Vue make great stuff, I'm sure you'll be happy with whatever you get.

Sorry to highjack the OP's thread but this is something I have wanted to get more info on for a while.

How do you find the Ethos in your 12" Dob?

Are stars sharp to the edge of the FOV?

Regards,
Stu.

[ausastronomer (John Bambury)]

Hi,

I have all 3 of the T4 Naglers (22mm, 17mm and 12mm) amongst about 20 other Televue, Pentax and other premium eyepieces. I use these in several different newtonians.

IMO the 17mm and 22mm Naglers don't perform all that well in an F5 newtonian unless used with a paracorr, which by itself is an expensive item. When used in combination with a paracorr these 2 eyepieces perform superbly.

Also be aware that if you have a 1.25" barlow you cannot use it with the 17mm Nagler, which has a 2" only barrel.

Further, I don't think these 3 eyepieces give a big enough range, nor utilise your barlow to it's maximum potential.

Understanding you want long eye relief and good comfort and assuming your barlow is 1.25" and you don't own a paracorr, I would consider going along the following lines.

26mm Televue Nagler
14mm Televue Delos barlows to 7mm
10mm Televue Delos barlows to 5mm

You can't barlow the 26mm Nagler but it gives you a much larger true field of view than the 17mm and doesn't need a paracorr to perform at it's best in an f5 newtonian.

This lineup gives you the following magnifications and exit pupils.

26mm = 38x with a 5mm exit pupil ideal bottom end
14mm = 70x with a 2.9mm exit pupil
10mm = 100x with a 2mm exit pupil
7mm = 140x with a 1.4mm exit pupil
5mm = 200x with a 1mm exit pupil

All of these will work well in your scope without a paracorr.

This gives you a good spread for both deep sky and planetary observing. If you wanted to add a 4th eyepiece into the range then I would do things a bit different to this.

Cheers,
John B

[wavelandscott (Scott)]

Originally Posted by ausastronomer

IMO the 17mm and 22mm Naglers don't perform all that well in an F5 newtonian unless used with a paracorr, which by itself is an expensive item. When used in combination with a paracorr these 2 eyepieces perform superbly.

Further, I don't think these 3 eyepieces give a big enough range, nor utilise your barlow to it's maximum potential.

Understanding you want long eye relief and good comfort and assuming your barlow is 1.25" and you don't own a paracorr, I would consider going along the following lines.

26mm Televue Nagler
14mm Televue Delos barlows to 7mm
10mm Televue Delos barlows to 5mm

You can't barlow the 26mm Nagler but it gives you a much larger true field of view than the 17mm and doesn't need a paracorr to perform at it's best in an f5 newtonian.

This lineup gives you the following magnifications and exit pupils.

All of these will work well in your scope without a paracorr.

This gives you a good spread for both deep sky and planetary observing. If you wanted to add a 4th eyepiece into the range then I would do things a bit different to this.

Cheers,
John B

I agree with John and think his advice is sound.

He giving you some suggestions of great glass that will really shine in your scope today but also last a lifetime!

I am a fan of buying the best you can once in your life and then using it forever.

[philipheaven (Philip)]

Thanks for the advice guys - there is plenty here to consider.

[philipheaven (Philip)]

How about eyepieces from the Panoptic range? They haven't been discussed yet. Should I consider some of those, or just stick with the 2inch Naglers for achieving larger FOV?

[Gem (Grant)]

Originally Posted by philipheaven

How about eyepieces from the Panoptic range? They haven't been discussed yet. Should I consider some of those, or just stick with the 2inch Naglers for achieving larger FOV?

FOV isn't always everything and the Pano are great EPs. Excellent value. My 24mm Pano is my most used EP. To be honest, EP choice really depends a lot on the type of objects you want to be viewing. It is also very subjective. What works for someone, doesn't for someone else.
The best advice is - get some good astro friends and try their EPs in your scope!

[barx1963 (Malcolm)]

Originally Posted by Shark Bait

Sorry to highjack the OP's thread but this is something I have wanted to get more info on for a while.

How do you find the Ethos in your 12" Dob?

Are stars sharp to the edge of the FOV?

Regards,
Stu.

I used a couple of Ethos in my old 12' f5 and had no dramas with the sharpness. The field is so large that you really don't notice the edge while observing, but when I have checked it seems sharp. Also when observing, and others have commented on this, the image at the centre is noticeably sharper. That may just be a case of heightened expectations but I am convinced that the image comparing a 13mm Ethos to a 13mm Nag, the Ethos was sharper and more contrasty.

Malcolm

[philipheaven (Philip)]

Would it be safe to say that a 19mm or 24mm Panoptic would be a better purchase for my 8 inch f/5 Newtonian rather than a 17mm Nagler due to the fact that I do not plan on buying a paracorr anytime soon?

[MortonH]

Originally Posted by philipheaven

Would it be safe to say that a 19mm or 24mm Panoptic would be a better purchase for my 8 inch f/5 Newtonian rather than a 17mm Nagler due to the fact that I do not plan on buying a paracorr anytime soon?

I'd go for the 19mm over the 24mm. The 19mm gives a more useful magnification and resulting dark background IMO.

[JRC (John)]

Hi Morton it's John. I would very much agree with your picks; i have a 17mm Nagler IV - its a 2" eyepiece - but i just love looking through it, either through the C11 or through the Vixen 102s or the 120NA. ive had it since 2001 and its just wonderful - (i note its also currently about $200 less than i paid for it(note, Mike) but that would be the change in exchange rate) So much so i am thinking of getting a 13mm type 6 some time. I also have a lot of Vixen LVs ( 20, 15, 12, 9, 4) which are cheaper but have really good eye relief. i have a TV 7 mm nagler IV (the older model) which i like on the short focus vixen but not so much on the SCT. I had a vixen LV 9 with me the other night that is probably my favourite vixen!

[Don Pensack]

I think a lower low power would be more useful on an 8" scope. The 26mm Type 5 Nagler would be a great choice as a low-power eyepiece. Alternatively, the 22mm Type 4 Nagler.
If you didn't mind less eye relief, even the 24mm Panoptic would be a great choice.
I think a 17mm is a little high for a lowest-power.

The 12mm would be an excellent middle, and the 8mm Delos an excellent higher power. You could save a bit and get a 12 Delos as the middle power. That would hardly be a sacrifice. If you did that, I'd tend to go for the 22mm T4 Nagler as a low power, since its eye relief is closer to the Delos series and it has a wonderful immersive character to its field.

You'll want a good 2X 1.25" barlow to yield the higher powers. There are many good choices in the market. One of the best inexpensive ones is the 4-element Explore Scientific 2X Focal Extender, which works well with those eyepieces. The TeleVue 2X barlow is also good, but retails for more.

At one point, I owned the 12mm T4 Nagler and the 13mm T6 Nagler. I kept the 13 because it was better in my f/5 scopes in the outer 50% of the field and because it was superbly sharp. In my dob, I balanced its light weight with the 12 ounce brass "Equalizer" adapter from TeleVue. The eyepiece that replaced it, the 13 Ethos, didn't need the extra weight in the adapter.

[philipheaven (Philip)]

Thans for the insight Don. I think your right about the 8mm Delos being an excellent high power eyepiece. I will lock that one in. I also have a Televue barlow.

As for eye relief, I'm not too fussed about it. I'm think I'm going to go for the 13mm T6 Nagler. I've heard nothing but good things about it - sharp to the edge of view etc.

I've taken on the advice John as well and decided to steer clear of the 17mm Nagler due to how fast my scope is and the fact I don't want to have to purchase a paracorr just to make what is already a $500 eyepiece work superbly.

That means I'm on the hunt for a low power, wide angle eye piece suitable for my f/5 Newtonian. Leaning towards the 24mm Panoptic…….