16 replies to this topic

[Dr Arnheim]

Dear All,

 

I would like to know how many eyepieces you are using in your binoscope or double telescope. I bought the 4.5mm, 6.5mm, 12.5mm and 17.5mm from the Morpheus line and a 3.5mm XWA. I also want to acquire one other set of eyepieces or barlows to get a magnification of around 200-240x and one ultra wide (30mm UFF or 35mm Siebert Optics). The original plan was to try all these eyepieces and then keep the ones that I use most. However, now I see myself using all the eyepieces all the time. I store my eyepieces inside my living room and usually only go out with two different focal lengths, however, at the end of the night I find usually all of my eyepieces around me. Somehow I always have the urge to frame an object more perfect or want to try if another magnification can entice more detail from an object. Am I making a fuss and should concentrate more on observing or is it quite normal and useful to use so many eyepieces? Of course this is highly subjective but I'm just interested how others observe.

 

Btw, this is a list from my most used eyepiece (top) to my least used one (bottom):

1. Morpheus 12.5mm

2. XWA 3.5mm

3. Morpheus 17.5mm

4. Morpheus 6.5mm

5. Morpheus 4.5mm

 

Thanks,

Arnheim

[triplemon]

To help guessing what focal length corresponds to 200-240x power, what is the focal length of the scope ? And do you use a barlow built in the BV ? Bumping that barlow would be the obviou choice, given you have a XWA pair already and at 50x / inch and above that won't be a magnification your are going to use very often.

Similar with the ultra-wide suggestion - the 30 UFF is a 2" only eyepiece.  Do you want a UW for binoviewer use or for use as a single EP with a 2" diagonal ?

Edited by triplemon, 21 March 2025 - 04:57 PM.

[Dr Arnheim]

Well, for us to guess what focal length corresponds to 200-240x power, you'd have to share the focal length of the scope. And if the BV has any barlows built in.

Similar with the ultra-wide suggestion - the 30 UFF is a 2" only eyepiece.  Do you want a UW for binoviewer use or for use as a single EP with a 2" diagonal ?

Ah sorry, it is the one in my signature the Borg double telescope with a focal length of 600mm, so at the moment I can cover 34x-171x but I want to cover 20x-200-240x ...

[Lookitup]

With FL 740 (Tak 100DF), 975 (SM 125ED) and 1111 (Planeta 101) in the Binotron, my most used EP's are:

 

1. Pentax XW 10mm

2. Morpheus 12.5mm

3. Vixen SSW 10mm

4. Morpheus 17.5mm

5. Denkmeier 14mm

[balcon3]

You have what seems to be a wonderful binoscope. I see no reason to limit your eyepiece collection. In a mono telescope, all these eyepieces would be useful, so I think they should be useful for a binoscope as well. There are some limiting factors. It is more of a pain to switch two eyepieces rather than one. And holding the small exit pupil on two 2.5mm eyepieces simultaneously might get tricky. But if I had a scope like that I would choose eyepieces just like I do on my 100mm mono refractor. By the way, you have a big gap between 12.5mm and 6.5mm. The Morpheus 9mm is a very nice eyepiece, maybe the best of the line. 

[astrophile]

> “usually only go out with two different focal lengths, however, at the end of the night I find usually all of my eyepieces around me”

LOL 👍🏻
That means you didn’t go overboard yet! Enjoy…

[fishhuntmike]

TV 32mm
UFF 24mm
OB 22mm
Morpheus 17.5, 12.5, 9
Pentax 10XW
Delos 6mm

I mostly use the 17.5 and 12.5 and third is a tossup between the 24 and the 9

Edited by fishhuntmike, 21 March 2025 - 07:23 PM.

[Tamiji Homma]

Here is my list.

 

Docter UWA 12.5 for TEC 140mm f/7 and Swarovski 95mm f/5.8

Nikon NAV SW 17.5 for Oberwerk BT-70XL-ED 70mm f/5.6

Kowa 21 for Kowa Highlander 82mm f/5.5

Panoptic 27 for Swarovski 95mm f/5.8

APM UFF 30 for TEC 140mm f/7

 

Tammy

[K-night]

NT 102mm f/7:

1. SR UF 30mm

2. SR UF 10mm (with ND96-0.3 filter)

3. Noblex UWA 12.5 (but it is number 1 and fulltime in the  BT APO70mm f/5.7) 

[jrazz]

 

from most to least used:

AT UWA 16mm

AT UWA 7mm

AT UWA 4mm

AT UWA 10mm

Takahashi TOE 2.5mm

Sky Rover UFF 30mm

 

The 16 and 7mm get used 90% of the time. The rest get used very sporadically. The 10 is fine but somewhat unremarkable. The 4 is great for doubles when the seeing is spectacular. The 2.5 is just too dim and narrow. It only works for extremely tight and bright doubles on exquisite seeing.

 

The 30mm are a complete disappointment. Uncomfortable, distorted and soft.

[Dr Arnheim]

 

 

 

from most to least used:

AT UWA 16mm

AT UWA 7mm

AT UWA 4mm

AT UWA 10mm

Takahashi TOE 2.5mm

Sky Rover UFF 30mm

 

The 16 and 7mm get used 90% of the time. The rest get used very sporadically. The 10 is fine but somewhat unremarkable. The 4 is great for doubles when the seeing is spectacular. The 2.5 is just too dim and narrow. It only works for extremely tight and bright doubles on exquisite seeing.

 

The 30mm are a complete disappointment. Uncomfortable, distorted and soft.

 

Hello Jordan,

Very interesting. Your most used 16mm eyepieces yields almost the same magnification in your 740mm DT as my 12.5mm in my 600mm DT. There are two other things you are mentioning that are very interesting:

First, I understand that the 2.5mm is too dim in your 740mm telescope yielding a 296x magnification, however, the next longer eyepiece (4mm) you are using is getting you to 185x. Are you planing to buy something in between these eyepieces for double stars? Which focal length would make sense here in your opinion?

Secondly, to the best of my knowledge the UFF 30mm Sky Rover is the same eyepiece like the UFF 30mm from APM which usually gets high praises in the forum here. Since you have two of them I guess it is rather unlikely that you have received 2 bad samples - right? I'm asking because the 30mm UFF is own my shopping list.

[jrazz]

Under my sky I rarely find a need to go beyond 185x. I don't get any more details, just a dimmer view. The 2.5mm were far more usable in the BT-100XL where they yielded 224x and a bigger exit pupil. Part of the reason for going with a DT was the longer focal length.

 

Ditto for the 16mm. The magnification of ~50x seems to be a sweet spot for these 100mm DTs/BTs. With an exit pupil of roughly 2mm you get a really bright, detailed, colorful view. Again, in the BT-100XL I used 10mm a lot.

 

The Sky Rover 30mm is the same as the APM. I got them because of the praise and I am deeply disappointed. It could be just my eyes and my use case but they are uncomfortable to use and are surprisingly soft to my eyes. I am planning on selling them because I just don't enjoy using them. If I need wide views I much rather use the Astroluxe. BTW, I had the same experience with the 24mm UFF so maybe I shouldn't be surprised. I just don't get along with those eyepieces.

[Chuck2]

Don't own a DT, but similar observing in my BT126 / 625mm fl

 

#1 - Vixen SSW 14mm, 83* FOV, at 45x

#2 - Vixen LVW 22mm, 65* FOV, at 28x

#3 - Vixen SSW 10mm, 83* FOV, at 63x

 

The 14mm is my most used set as they produce darker sky background, more contrast, sufficient magnification to resolve globulars and finer details in nebula, all with an immersive FOV to frame beep sky objects. I attached eye cups to shield stray light to further increase mag limit.

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Edited by Chuck2, 24 March 2025 - 02:27 AM.

[warpsl]

Gso 32mm plossl es 24mm 68 denkmeier d14 pentax xf 8.5mm

[cimar]

I use the following eyepiece pairs with my BTs:

 

10mm UWAs

15mm UFFs

18mm UFFs

24mm UFFs

 

The 10mm UWAs and the 18mm UFFs gets used most frequent, the 15mm are good for galaxies at the spring skies, the 24mm for the summer milky way.

 

Currently I am thinking about buying a pair of 16mm UWAs to replace the 15mm UFFs

What do you think about this move?

 

Thanks!

[Faber]

With my binoscope takahashi fc 100 dl I use these eyepieces:
Pentax XW 20
Pentax XW 10
Pentax XW 5
UFF 18

Perhaps I need a long focal couple.
Regards

[edwincjones]

In my Miyauchi 100mmFL I have three

 

20X that came with the optics that I use more for public star parties

26X higher quality that I use for personal viewing

37X that I  use only when I want /need higher mag

 

edj