40 mm wide field eyepiece

[John]

I was thinking of the Nikon NAV HW's but with the EiC tele-extender you do get 2 focal lengths out of each one:

https://www.apm-telescopes.de/en/product.html?shopgate_redirect=1&mobile=false&info=2769

A bit wasted on me though, not using 17mm much.

The Docter 12.5mm are reputed to be a little better than the 13mm Ethos but I've just remembered that they have recently gone out of production:

https://www.astroshop.eu/eyepieces/docter-12-5mm-1-25l-2l-ultra-wa-eyepiece/p,22974

Like Gerry, I paid around half that for my Ethos 21 (used) but that was a few years back now.

I notice that the ES 92's are now £400+ eyepieces now as well.

 

[Deadlake]

15 minutes ago, John said:

I was thinking of the Nikon NAV HW's but with the EiC tele-extender you do get 2 focal lengths out of each one:

https://www.apm-telescopes.de/en/product.html?shopgate_redirect=1&mobile=false&info=2769

A bit wasted on me though, not using 17mm much.

The Docter 12.5mm are reputed to be a little better than the 13mm Ethos but I've just remembered that they have recently gone out of production:

https://www.astroshop.eu/eyepieces/docter-12-5mm-1-25l-2l-ultra-wa-eyepiece/p,22974

Like Gerry, I paid around half that for my Ethos 21 (used) but that was a few years back now.

I notice that the ES 92's are now £400+ eyepieces now as well.

 

I thought you where going to mention this:

https://www.firstlightoptics.com/explore-scientific-eyepieces/explore-scientific-100-degree-series-2-inch-eyepieces.html

£954.50

i can get an entire range of APM epks for that....

 

[John]

18 minutes ago, Deadlake said:

I thought you where going to mention this:

https://www.firstlightoptics.com/explore-scientific-eyepieces/explore-scientific-100-degree-series-2-inch-eyepieces.html

£954.50

i can get an entire range of APM epks for that....

 

That 3 inch 30mm is a monster !

 

[jetstream]

1 hour ago, John said:

The Docter 12.5mm are reputed to be a little better than the 13mm Ethos but I've just remembered that they have recently gone out of production:

Unfortunately this was just a matter of time IMHO, one specialty eyepiece made by some remaining craftsmen of a former Zeiss branch.Expensive to make and a limited market.

It is just a different eyepiece, the Ethos has the same contrast but with that great apparent 100 deg FOV. The Docter is more constricted at 84 deg, has fussier eye placement but with a hair sharper view IMHO.

Either one is welcome in the collection John. I think that the Pentax XW series is the best deal and with some of the best glass available currently. If buying new I know what I'd be looking at 10mm and down, plus the 30mm.

[Don Pensack]

On 14/02/2021 at 14:19, Deadlake said:

Would it make a difference with a 40 mm 1.25” vs a 2” ep?

Sky brightness in the eyepiece, no.  The same.

Field size, huge.  The 2" would have nearly 3x the area of field.

[Don Pensack]

3 hours ago, John said:

I'm sorry - I missed this question.

17mm is my most underused focal length. I replaced the Ethos 17mm with an ES 17mm / 92 because of this and I've thought about letting my 17.3mm Delos go as well but I keep finding excuses to hang onto it, usually after I've read a report from someone else saying how much they like the eyepiece

I guess a 17.5mm Morpheus would fill the gap very adequately but, as I tend to move directly from 20-something mm eyepieces to 13mm / 14mm eyepieces the poor 17mm's get overlooked so the Morpheus would get similar treatment I expect.

Other than that, I think my current Tele Vue's are "keepers". Probably .......

There are a few out there that might be a touch better in certain focal lengths but they cost even more than the Ethos's do.

 

 

I have 30mm (UFF), 22mm (NT4), 17.5mm (M), 14mm (M), 11mm (Apollo), for glasses, and  8mm (E), 6mm (E), 4.7mm (E-SX), 3.7mm (E-SX), without glasses, in a scope with an 1826mm coma-corrected focal length.

I tend to use them in "sets", i.e. 30, 17.5, 11mm one night, and 22mm, 14mm, 11mm the next night.

It depends on what I am observing, whether I'm using a filter or not, whether I want the extreme low power of the 30mm, how good the seeing is, 

the darkness of the sky.  

I can't say I ever use all 5 eyepieces of 11mm and longer on the same night--I don't need the magnifications that close together.

So you could justify keeping the 17mm or 17.3mm if there are times it gets used along with the next jump down or up.

But if it's never used, it should get a new home where it will get a lot of love.

 

[Stardaze]

For what it's worth I have the APM 20 and 13 and think they're great EP's, certainly not bettered for the money imo. I do hanker after the Ethos 13 at times but honestly, the APM 13 still blows me away when I use it, they are my go-to EP's and get used most nights unless it's lunar and planetary viewing of course. 

I have also debated the APM 30 for a while, it won't give me much extra in terms of FOV but the exit pupil would be 6.04mm in my 10" dob over the 4.03mm the APM 20 currently gives me, which may be useful with a filter purely for nebula use. My skies are 20.54 so quite average and it's this that keeps me sitting on the fence. Just one point though regarding the APM 30, it is over 1kg in weight. I've skim read the thread so that may have been pointed out already, but that's significantly heavier than the APM 20 and might be tricky to balance for you? The XW30 is only 740g by comparison. I don't think you'll go far wrong with anything you've mentioned to date.

[Deadlake]

4 hours ago, Stardaze said:

For what it's worth I have the APM 20 and 13 and think they're great EP's, certainly not bettered for the money imo. I do hanker after the Ethos 13 at times but honestly, the APM 13 still blows me away when I use it, they are my go-to EP's and get used most nights unless it's lunar and planetary viewing of course. 

I have also debated the APM 30 for a while, it won't give me much extra in terms of FOV but the exit pupil would be 6.04mm in my 10" dob over the 4.03mm the APM 20 currently gives me, which may be useful with a filter purely for nebula use. My skies are 20.54 so quite average and it's this that keeps me sitting on the fence. Just one point though regarding the APM 30, it is over 1kg in weight. I've skim read the thread so that may have been pointed out already, but that's significantly heavier than the APM 20 and might be tricky to balance for you? The XW30 is only 740g by comparison. I don't think you'll go far wrong with anything you've mentioned to date.

Thanks, the APM 30 mm is lightweight compared with the Nagler and Ethos alternative. However this is to go on a 130 mm triplet, so in this case good ballast for the lens, but maybe will need some extra weights for the GEM. 😀

yes, the more I think about it the more APM XWA makes good sense as they are all parfocal with the range, just like Tele Vue ranges. I suspect in certain cases another brand will be better however the question is the cost and how much you use them. I suspect for most people (given the cost of Televue) a better or different scope would be the answer.  

My concern over the APM 30 is to use 21 SQM is a frequent number that comes up when used with a UHC or OIII filter. I think its worth trying it as the skys luminosity is very directional where I live. London and other towns are hidden behind the Surrey Hills, however still have light bouncing around. I do find a UHC makes a difference when observing Orion's Nebulae.  

Edited February 16, 2021 by Deadlake

[Don Pensack]

9 hours ago, Stardaze said:

For what it's worth I have the APM 20 and 13 and think they're great EP's, certainly not bettered for the money imo. I do hanker after the Ethos 13 at times but honestly, the APM 13 still blows me away when I use it, they are my go-to EP's and get used most nights unless it's lunar and planetary viewing of course. 

I have also debated the APM 30 for a while, it won't give me much extra in terms of FOV but the exit pupil would be 6.04mm in my 10" dob over the 4.03mm the APM 20 currently gives me, which may be useful with a filter purely for nebula use. My skies are 20.54 so quite average and it's this that keeps me sitting on the fence. Just one point though regarding the APM 30, it is over 1kg in weight. I've skim read the thread so that may have been pointed out already, but that's significantly heavier than the APM 20 and might be tricky to balance for you? The XW30 is only 740g by comparison. I don't think you'll go far wrong with anything you've mentioned to date.

The APM 30mm UFF is only 556g.

[Stardaze]

16 hours ago, Don Pensack said:

The APM 30mm UFF is only 556g.

Thanks Don. I noted the weight from APM’s site which surprised me.

[Don Pensack]

That's the shipping weight.

[Stardaze]

3 hours ago, Don Pensack said:

That's the shipping weight.

Ah ha, hadn’t thought that that would be noted. Makes sense. 

[Carl Au]

On 13/02/2021 at 21:35, John said:

Until recently I had a 40mm Aero ED. These were originally available in the USA under the Astro Tech branding as their Titan II range and I believe had the same optics in them as the TMB Paragons. The Paragon range was 40mm and 30mm. The Aero ED's included a 35mm as well. I had the 30mm and the 40mm. The 30mm was quite good but the 40mm was excellent. Very well corrected at the edge of field for it's price in my F/6.5 Vixen ED 102 refractor and even in my F/5.3 12 inch dobsonian although the exit pupil was not terribly effective in that latter scope.

The Aero ED's (also available under other brandings) are also reasonably light for 2 inch eyepieces.

Unfortunately I can't see the 40mm listed anywhere now but if you do come across one they are worthy of serious consideration for use in F/6 and slower scopes.

I let mine go for a silly price a couple of months back simply because I find shorter focal length UWA's and Hyper-Wides more effective under my moderately light polluted skies. Probably should have hung onto it

 

I just bought the 30mm TS Optics/TMB/Aero (I got mine from TS) and my first impressions are really very good indeed, in my fl7 4 inch frac at least. I know they are not they arn't in the same league as TV, but they are pretty good for around a 100 quid, amazing value for money. They look at feel like exactly WO eyepieces I have handled in the past and I certainly wouldn't have a problem owning a full set of them if they perform like this one, the field is very flat. I am going to do a proper review of the 30 mm once I have given it a few proper goes in the field. I am however a one scope bloke so the Dob brigade may have other opinions. 

[Carl Au]

On 17/02/2021 at 13:38, Stardaze said:

Thanks Don. I noted the weight from APM’s site which surprised me.

Interesting the clone I have has 6 elements: https://www.teleskop-express.de/shop/product_info.php/info/p2335_TS-Optics-30-mm-2--UFL-Eyepiece---69--Field-of-View---6-Element-Design.html 

[Deadlake]

I've gone for this one:

 

http://astrograph.net/epages/www_astrograph_net.sf/en_GB/?ObjectPath=/Shops/www_astrograph_net/Products/AGAPMUFF30

and a few others. Have a dark site I can visit at 21.2 SQM so can make use of it with a SIII filter.

[Carl Au]

11 minutes ago, Deadlake said:

I've gone for this one:

 

http://astrograph.net/epages/www_astrograph_net.sf/en_GB/?ObjectPath=/Shops/www_astrograph_net/Products/AGAPMUFF30

and a few others. Have a dark site I can visit at 21.2 SQM so can make use of it with a SIII filter.

They have got to be the same eyepice, the clones are everywhere I tell ya, everywhere!

[Louis D]

1 hour ago, Carl Au said:

They have got to be the same eyepice, the clones are everywhere I tell ya, everywhere!

The 30mm APM UFF is an entirely different design from the 30mm Aero ED (TMB Paragon originally).  And these are not to be confused with the APM UW 30mm 80° which is yet another entirely different design.

I think part of the confusion is all are (most likely) made (but not designed) by KUO in China, so they have very similar build qualities.

[Carl Au]

23 minutes ago, Louis D said:

The 30mm APM UFF is an entirely different design from the 30mm Aero ED (TMB Paragon originally).  And these are not to be confused with the APM UW 30mm 80° which is yet another entirely different design.

I think part of the confusion is all are (most likely) made (but not designed) by KUO in China, so they have very similar build qualities.

Interesting, thank you, I am not alone in thinking this, In what way are they different?

Edited February 20, 2021 by Carl Au

[Carl Au]

Forget it,  I can see now. 9 elements, mine has only 6. 

Edited February 20, 2021 by Carl Au

[Louis D]

18 minutes ago, Carl Au said:

Interesting, thank you, I am not alone in thinking this, In what way are they different?

The oldest of the designs is the APM UW 30mm 80° which is a Markus Ludes commissioned clone of the 30m KK Wide Scan II (or III, I can't remember) which was a Japanese designed and built UWA of the 90s.  It has 5 elements, massive field curvature, excellent central sharpness, long eye relief, and very good edge correction once field flattened.

The TMB Paragon came next about 15 years ago.  The 30mm and 40mm versions were designed by the late Thomas M. Back.  The 35mm version was inspired by his designs.  They have very good correction for their size and weight, 6 elements, shorter eye relief, and flat fields.  The design was cloned by multiple Chinese optical shops (as were TMB's 58° Planetary line).

The APM UFF came last about 4 years ago.  They were designed by Mark Ackermann for APM.  Since then, they've been sold by KUO to multiple vendors.  The designs are shown below:

[Carl Au]

53 minutes ago, Louis D said:

The oldest of the designs is the APM UW 30mm 80° which is a Markus Ludes commissioned clone of the 30m KK Wide Scan II (or III, I can't remember) which was a Japanese designed and built UWA of the 90s.  It has 5 elements, massive field curvature, excellent central sharpness, long eye relief, and very good edge correction once field flattened.

The TMB Paragon came next about 15 years ago.  The 30mm and 40mm versions were designed by the late Thomas M. Back.  The 35mm version was inspired by his designs.  They have very good correction for their size and weight, 6 elements, shorter eye relief, and flat fields.  The design was cloned by multiple Chinese optical shops (as were TMB's 58° Planetary line).

The APM UFF came last about 4 years ago.  They were designed by Mark Ackermann for APM.  Since then, they've been sold by KUO to multiple vendors.  The designs are shown below:

Excellent, thank you for taking the time to explain. 

[Deadlake]

@jetstream Gerry told me similar to Nagler 31 mm but lighter (Sure I’ll get corrected if wrong model) but lighter and not much difference. Hence I went with the APM, I don’t have Gerry’s dark skies.

Edited February 20, 2021 by Deadlake

[jetstream]

3 minutes ago, Deadlake said:

@jetstream Gerry told me similar to Nagler 31 mm but lighter (Sure I’ll get corrected if wrong model) but lighter and not much difference. Hence I went with the APM, I don’t have Gerry’s dark skies.

Going from what I hear the 30mm UFF is the eyepiece to have. Some respected astro colleagues have given it high praise and one had the 30 ES 82 to compare it to- and it left...

[Don Pensack]

7 hours ago, Carl Au said:

Interesting the clone I have has 6 elements: https://www.teleskop-express.de/shop/product_info.php/info/p2335_TS-Optics-30-mm-2--UFL-Eyepiece---69--Field-of-View---6-Element-Design.html 

That's because that's a completely different eyepiece internally, not merely a rebranded clone.

The clones are from Meade, Celestron, Altair, APM, Tecnosky.

[Deadlake]

On 20/02/2021 at 19:46, Don Pensack said:

That's because that's a completely different eyepiece internally, not merely a rebranded clone.

The clones are from Meade, Celestron, Altair, APM, Tecnosky.

Is the Stellarvue a clone of the XWA design, just a baffle and a steel tube on the bottom? Shame not available outside of US.