Orthoscopic vs wide field.

[quasar117]

Looking at purchasing a few mid to high power eyepieces for planetary,  lunar and double stars for the soon to be arriving Starfield 102 F/7.

On a bit of a tight budget for eyepieces as I have splurged on the rest of the setup...

Would I best going for a set of Otho's such as the BCO or Masyuama Abbe ortho's or wider fields such as Starguiders and Nirvana's?

 

I'm aware of the short comings of Ortho's for FOV and eye relief,  but would that be a good sacrifice for better contrast and sharpness across the field?

 

 

[John]

In my opinion, the 10mm and 18mm Baader Classic Orthos perform as well, in pure optical terms, as eyepieces that cost £100's more. So if you can live with the smaller field of view and eye relief around 80% of the focal length, then they, and other orthos such as the Fujiyamas and Astro Hutechs, will do a great job for you.

The wider fields of view are nice to have but not essential by any means. Many folks are happy to use "standard" field of view eyepieces (ie: 40-60) degrees).

A viable alternative, again in my opinion, would be one of the Svbony 3mm-8mm zooms which seem to me to perform as well as good quality fixed focal length eyepieces but you effectively get 4-6 (depending on what you use) focal lengths for your £100 (approx) investment.

 

Edited March 3 by John

[quasar117]

Would the 10mm and 18mm Orthos compliment the SVbony 3-8mm zoom?

If so all I would need would be a low power for nebulae and bright DSO's to get me started.

[John]

7 minutes ago, quasar117 said:

Would the 10mm and 18mm Orthos compliment the SVbony 3-8mm zoom?

If so all I would need would be a low power for nebulae and bright DSO's to get me started.

Personally I think you would still want something around 13mm focal length for mid powers and also a "lowest / widest" eyepiece so perhaps a 30mm such as the Vixen NPL 30mm ?

Even better would be something like a 24mm UFF but I'm assuming that your budget will not stretch that far at the current time. I'm also assuming that you stay with the 1.25 inch fitting for now as well.

See what others suggest - there are usually lots of good opinions on eyepiece choices forthcoming on here 🙂

 

[Mr Spock]

A 4mm eyepiece would give you x179 which is a decent magnification but below what the Starfield is capable of.  A 3mm would give x238, so the Svbony 3-8 is useful, going from x238 to x89. 
I've not seen much difference between my orthos and the Nirvanas, other than the latter being twice the fov! I can't recommend the 16mm, but the 13mm is excellent and would give you x55 and 1.5°.

[Ratlet]

36 minutes ago, Mr Spock said:

A 4mm eyepiece would give you x179 which is a decent magnification but below what the Starfield is capable of.  A 3mm would give x238, so the Svbony 3-8 is useful, going from x238 to x89. 
I've not seen much difference between my orthos and the Nirvanas, other than the latter being twice the fov! I can't recommend the 16mm, but the 13mm is excellent and would give you x55 and 1.5°.

Very slightly related, but do you think the 16mm would be improved with a slower scope?

[Ags]

I used the Nirvana 16 at f5, f10 and f13 and found it equally objectionable at any focal ratio. It was good on the Moon in my f13 scope though...

[Ratlet]

Just now, Ags said:

I used the Nirvana 16 at f5, f10 and f13 and found it equally objectionable at any focal ratio. It was good on the Moon in my f13 scope though...

I was afraid of that.  Looks like it'll be going to the scouts with the lt80 I pilfered a starsense from.  Feel bad selling it on.

[Ags]

I too felt it was too bad to sell, but someone read my loud complaints about the eyepiece and offered to buy it.

Other people have looked through the Nirvana 16 and compared it favorably with the Nagler 16. I can't account for such divergence of opinion.

Edited March 3 by Ags

[radiofm74]

3 hours ago, quasar117 said:

Looking at purchasing a few mid to high power eyepieces for planetary,  lunar and double stars for the soon to be arriving Starfield 102 F/7.

On a bit of a tight budget for eyepieces as I have splurged on the rest of the setup...

Would I best going for a set of Otho's such as the BCO or Masyuama Abbe ortho's or wider fields such as Starguiders and Nirvana's?

 

I'm aware of the short comings of Ortho's for FOV and eye relief,  but would that be a good sacrifice for better contrast and sharpness across the field?

 

 

I do have the Baader "Classic / Q-Turret" box including the 32 Plössl, 18 Ortho, 10 Ortho, 6 Ortho and a handy 2.25x barlow. It's been basically my only set of eyepieces until now (actually, living in two different places, I got me two of those on the used market). I subscribe fully to what John said above. If you can put up with the short eye relief in the 6, and do not expect good edge-of-view performance (the field stop is intentionally wider than normal in order to make finding objects easier) you're in for good experiences! The magnification range is also very well thought-out.

As other members know all too well, I am in the market for a new set of "wide" eyepieces, and I'm also getting a set of Vixen LV for longer eye relief and good planetary and lunar performance. I'm sure that I'll sell one of the two boxes as soon as the new EPs are home, but I don't think that I'll let both go. Those little orthos are very nice and in terms of cleanliness of the image they more than hold their own against more costly alternatives. The Plössl is also a nice wide eyepiece. 

Edited March 3 by radiofm74

[John]

I have compared the older "flat top" style William Optics UWAN 16mm to the 16mm T5 Nagler and found them roughly comparable in scopes slower than around F/8. In scopes faster than that the Nagler's better edge correction showed it's worth. At F/5 the differences were marked.

What I don't know is whether the UWAN 16mm is the same optically as the Nirvana 16mm being discussed - I thought it possibly was, but maybe not ?

 

Edited March 3 by John

[Don Pensack]

3 hours ago, quasar117 said:

Looking at purchasing a few mid to high power eyepieces for planetary,  lunar and double stars for the soon to be arriving Starfield 102 F/7.

On a bit of a tight budget for eyepieces as I have splurged on the rest of the setup...

Would I best going for a set of Otho's such as the BCO or Masyuama Abbe ortho's or wider fields such as Starguiders and Nirvana's?

 

I'm aware of the short comings of Ortho's for FOV and eye relief,  but would that be a good sacrifice for better contrast and sharpness across the field?

 

 

That depends.  If the scope is on a tracking mount, then go for narrowfield planetary eyepieces.  You can use eyepieces down to 3mm with that scope, though if you have a lot of floaters in your eye,

then stick to 4mm and longer.

If, however, the scope is not on a tracking mount, you will want something wider in field so you get longer drift times before having to move the scope.

My 102mm f/7 is on a non-tracking mount, and I found 62° eyepieces to be about the narrowest I could tolerate when focal lengths were 5mm or shorter.

Today, used for Moon, planets and double stars, I use 4.8mm (78°), 4.7mm (110°), and 3.7mm (110°).

i know most people don't consider those to be 'planetary' eyepieces, but the star images in all three are tiny little pinpoints from center to edge, and I can watch a crater on the moon go from edge to edge in good focus.

Mine is a triplet, not a doublet, so might have a better corrected edge of field in terms of chromaticism, but you get the point--wider fields will be more rewarding in a non-tracking scope.

In my 102mm, I could tolerate 62° of field, but felt happier with 70°+.  And there are wider field eyepieces that will yield sharp fields with excellent contrast, and have better eye relief.

I'm not against orthos, but they are harder to use.

 

If you can tolerate ultra-tight eye relief and have a tracking scope, then go for the narrower eyepieces if you prefer.

Though, on the Moon, a wider field is better for context and to see the environment around the feature of study.

[Zermelo]

The performance of the Nirvana 16mm has been discussed in several previous threads. Some people find it to be poor, but I have really liked mine, even in faster scopes. I wonder if there has been some QC variation in production over time.

On the OP's question, I'd agree with the previous recommendations. I still use my BCO 10mm a fair bit, despite the narrower view; it is very sharp and contrasty. I find the eye relief on the 6mm to be a bit too tight. The Svbony 3-8mm is a no-brainier, and the sale on Ali expressway may still be on - get it for under £100 shipped. The NPL 30mm is also excellent for widefield.

Edited March 3 by Zermelo
Typo

[quasar117]

 

Thanks for all the suggestions so far.

I forgot to mention I will be using the Starfield on a manually controlled GEM mount. Only planning on plonking it down, pointing north with correct latitude for location and then tracking with RA and occasional adjustments to the DEC. 

Hopefully this should be sufficient for the smaller FOV orthos. 

I've seen FLO are selling two variants of orthos: BCO and Masyuama. The later being more expensive. Is there any difference in quality/ performance of the two?

[quasar117]

3 hours ago, John said:

Personally I think you would still want something around 13mm focal length for mid powers and also a "lowest / widest" eyepiece so perhaps a 30mm such as the Vixen NPL 30mm ?

Even better would be something like a 24mm UFF but I'm assuming that your budget will not stretch that far at the current time. I'm also assuming that you stay with the 1.25 inch fitting for now as well.

See what others suggest - there are usually lots of good opinions on eyepiece choices forthcoming on here 🙂

 

Would something like the Stellarlyra 24mm UFF be a better option than the Vixen NPL 30mm? If so I think I could stretch the budget a bit.

Long term, would it be worth saving up for a 24mm Televue Panoptic to replace these for low power wide field?

[Don Pensack]

21 minutes ago, quasar117 said:

 

Thanks for all the suggestions so far.

I forgot to mention I will be using the Starfield on a manually controlled GEM mount. Only planning on plonking it down, pointing north with correct latitude for location and then tracking with RA and occasional adjustments to the DEC. 

Hopefully this should be sufficient for the smaller FOV orthos. 

I've seen FLO are selling two variants of orthos: BCO and Masyuama. The later being more expensive. Is there any difference in quality/ performance of the two?

The Masuyama eyepieces are classic Abbe Orthoscopic eyepieces, made in Japan.  AFOV about 42°.

The Baader eyepieces are also classic Abbe Orthoscopics, made in China.  AFOV about 50°.

The extra field width on the Baaders is not well-corrected, but might mean finding a target is a little easier.

 

In my limited experience, the Japanese-made orthos are a bit better, but recent production has included a LOT of eyepieces with dirt on internal lenses.  

The same maker, by the way, has made these same eyepieces since the '80s, when they were sold by University Optics.

[Don Pensack]

17 minutes ago, quasar117 said:

Would something like the Stellarlyra 24mm UFF be a better option than the Vixen NPL 30mm? If so I think I could stretch the budget a bit.

Long term, would it be worth saving up for a 24mm Televue Panoptic to replace these for low power wide field?

Yes.  Longer eye relief and wider apparent and true fields in the UFF.

[John]

46 minutes ago, quasar117 said:

Would something like the Stellarlyra 24mm UFF be a better option than the Vixen NPL 30mm? If so I think I could stretch the budget a bit.

Long term, would it be worth saving up for a 24mm Televue Panoptic to replace these for low power wide field?

I think the law of diminishing returns will apply to the difference between a 24mm UFF and a Panoptic 24mm. If you can get the 24mm UFF rather than the NPL 30mm then it's worth it.

I'm very fond of Tele Vues so I have the 24mm Panoptic, and the 19mm as well. Sweet little things compared with the 14mm Delos🙂

 

Edited March 3 by John

[quasar117]

1 hour ago, John said:

I think the law of diminishing returns will apply to the difference between a 24mm UFF and a Panoptic 24mm. If you can get the 24mm UFF rather than the NPL 30mm then it's worth it.

I'm very fond of Tele Vues so I have the 24mm Panoptic, and the 19mm as well. Sweet little things compared with the 14mm Delos🙂

 

Since I'm planning on buying a 2" diagonal, would the Stellarlyra 30mm UFF be superior to the 24mm UFF?

Or is it pointless getting a 2" diagonal if I can get excellent low power wide eyepieces in 1.25" format?

[radiofm74]

1 hour ago, quasar117 said:

 

Thanks for all the suggestions so far.

I forgot to mention I will be using the Starfield on a manually controlled GEM mount. Only planning on plonking it down, pointing north with correct latitude for location and then tracking with RA and occasional adjustments to the DEC. 

Hopefully this should be sufficient for the smaller FOV orthos. 

I've seen FLO are selling two variants of orthos: BCO and Masyuama. The later being more expensive. Is there any difference in quality/ performance of the two?

For my first year of astronomy, I have used the Baader set with a manual EQ mount. At the highest magnifications things would fly by quite rapidly but I must say that tracking with just one knob to turn is pretty good already. When I had my first RA motor I went "aaaaaah…". So get the small Fov eyepieces, and a little RA motor for your mount… nothing fancy, nothing photographic, just enough to keep your object in the FoV. My personal feeling! But to your question, it's not a sine qua non to use the BCOs

You mentioned longer eye relief, and if you want to go down that route I venture to mention the Vixen LVs (or their more modern series the NLVs and SLVs). I've read that they're a bit "dim" but they should make excellent, cheap (if bought used) and comfortable eyepieces for lunar, planetary and doubles. Their FoV is entirely comparable to that of the BCOs, but eye relief is 20mm. 

[Mr Spock]

4 hours ago, Ratlet said:

Very slightly related, but do you think the 16mm would be improved with a slower scope?

No, it suffers from field curvature. It's still sharp in the centre so I use it as a next to low power finder when I'm doing doubles. So I go 42mm LVW, then with the Nirvanas 16mm, 7mm (actually measures 8mm), and 4mm. A nice progression in the FC100 - x19 (3.7°), x46, x93, x185.

[John]

54 minutes ago, quasar117 said:

Since I'm planning on buying a 2" diagonal, would the Stellarlyra 30mm UFF be superior to the 24mm UFF?

Or is it pointless getting a 2" diagonal if I can get excellent low power wide eyepieces in 1.25" format?

I've not used a UFF myself but I believe that the 30mm is a slightly better performer than the 24mm although that is also a very nice eyepiece. The 2 inch 30mm shows a considerably larger true field of view of course. 

I use 2 inch diagonals in all my refractors now so I can pop in a 2 inch eyepiece when I want a really wide view. For medium to high powers though I'm usually using 1.25 inch eyepieces, though not always.

That is the main benefit of the 2 inch fitting - the wider field of view than the 1.25 inch format can deliver.

 

Edited March 3 by John

[Naughty Neal]

 For a budget mid power ep   I also agree the Nirvana 13mm is good, one could look at the Founder optics Alien ler 14.5.

The 10 & 18 BCO's are a no brainer even if only 50 degrees.

[Roy Challen]

13 hours ago, quasar117 said:

Would the 10mm and 18mm Orthos compliment the SVbony 3-8mm zoom?

If so all I would need would be a low power for nebulae and bright DSO's to get me started.

I was a long time fan of the BCOs (still am really, and of orthos in general) but imo the SvBony 3-8 is better in every way. However, the 10 and 18mm BCOs are complementary to the zoom. I also particularly like the Baader 32mm plossl for low power and HA solar use.

Edited March 4 by Roy Challen

[Roy Challen]

9 hours ago, quasar117 said:

 

Thanks for all the suggestions so far.

I forgot to mention I will be using the Starfield on a manually controlled GEM mount. Only planning on plonking it down, pointing north with correct latitude for location and then tracking with RA and occasional adjustments to the DEC. 

Hopefully this should be sufficient for the smaller FOV orthos. 

This is what I do, no faff at all. Some say a manual alt-az is less faffy, I disagree 😁. My EQ mount is much heavier though...