Jump to content

Banner.jpg.b89429c566825f6ab32bcafbada449c9.jpg

Explore scientific 24mm 68 degree


Recommended Posts

1 hour ago, Davesellars said:

I got this a little while back as ex-display from Bresser.de for 75 euros and it's really nice eyepiece and has spent a significant amount of time in my 120ST lately. Can't say I've noticed any real aberrations even at f/5 at the edge of the FOV.  Very well built and solid and has given awesome wide-field views.

It is a lovely EP, it does leave me with a conundrum I was going to get a 32mm as my final EP to complete my set.

But I'm not sure I need it now?

Richard

Link to comment
Share on other sites

  • Replies 35
  • Created
  • Last Reply
5 hours ago, Richard Hather said:

It is a lovely EP, it does leave me with a conundrum I was going to get a 32mm as my final EP to complete my set.

But I'm not sure I need it now?

Richard

A 32mm in the 1.25" format won't show any more sky than a 24mm 68 degree eyepiece so, unless you want the lower magnification for other reasons, you might be right.

 

Link to comment
Share on other sites

On ‎17‎/‎08‎/‎2016 at 15:26, Richard Hather said:

It is a lovely EP, it does leave me with a conundrum I was going to get a 32mm as my final EP to complete my set.

But I'm not sure I need it now?

Richard

Hi Richard,

I confess I'm not sure exactly what you mean here?

This is a relatively low power eyepiece, but does give you pretty much as wide a real view of the sky as you can get with a 1.25" eyepiece. The Pentax will beat it on contrast and resolution because it gives a higher magnification..as you increase magnification, you darken the sky background (especially in urban or semi-urban areas) and so the contrast is greater. If you compare your Pentax zoom at the 24mm setting, with the ES68 it would be interesting to hear what you see..they will be showing the same magnification, so any improvement in contrast visible with either should be due to superior performance of the eyepiece, whether in lens design, polish, coatings or whatever. I'd expect the Pentax, which has their proprietary SMC multicoatings, to slightly outperform the ES, but not by much, and for me the ES much wider FOV, at 68 degrees versus c40 degrees of the Pentax (at the 24mm setting), far outweighs any minor contrast improvement.

Regarding a 32mm ep, I personally would not recommend selling the ES24 mm to replace it with a 32mm, but rather, to keep it and ADD a 30mm+ focal length eyepiece to your stable. Most of the 30mm plus eps will be 2" barrels, and these will give you a wider true field of view. I myself have the ES 34mm as well as the 24mm, and they are both great. The 34mm, however, is MUCH bigger and heavier than the 24mm, so be aware of that. Also, if you have a lot of light pollution, the lighter sky background in the 34mm might be more than you can tolerate. But on a good, dark night, objects such as the double cluster in Perseus are stunning in the 34mm.

Another option is a 30mm ep in a 1.25" barrel, which will keep the weight down. A surprisingly good eyepiece for budget cost is the Vixen NPL 30mm. I really like the one I had, it was extremely sharp across the whole field, however being a plossl the trade off is that it is only a 50deg field of view. But for low power sharp views in a 1.25" barrel it's extremely good.

Hope that helps a bit:-)


Dave

Link to comment
Share on other sites

On 8/17/2016 at 15:26, Richard Hather said:

It is a lovely EP, it does leave me with a conundrum I was going to get a 32mm as my final EP to complete my set.

But I'm not sure I need it now?

Richard

who said anything about need!?!

Did you get out last night? it was beautiful, if a little bit bright, round our way.

Link to comment
Share on other sites

10 hours ago, F15Rules said:

Hi Richard,

I confess I'm not sure exactly what you mean here?

This is a relatively low power eyepiece, but does give you pretty much as wide a real view of the sky as you can get with a 1.25" eyepiece. The Pentax will beat it on contrast and resolution because it gives a higher magnification..as you increase magnification, you darken the sky background (especially in urban or semi-urban areas) and so the contrast is greater. If you compare your Pentax zoom at the 24mm setting, with the ES68 it would be interesting to hear what you see..they will be showing the same magnification, so any improvement in contrast visible with either should be due to superior performance of the eyepiece, whether in lens design, polish, coatings or whatever. I'd expect the Pentax, which has their proprietary SMC multicoatings, to slightly outperform the ES, but not by much, and for me the ES much wider FOV, at 68 degrees versus c40 degrees of the Pentax (at the 24mm setting), far outweighs any minor contrast improvement.

Regarding a 32mm ep, I personally would not recommend selling the ES24 mm to replace it with a 32mm, but rather, to keep it and ADD a 30mm+ focal length eyepiece to your stable. Most of the 30mm plus eps will be 2" barrels, and these will give you a wider true field of view. I myself have the ES 34mm as well as the 24mm, and they are both great. The 34mm, however, is MUCH bigger and heavier than the 24mm, so be aware of that. Also, if you have a lot of light pollution, the lighter sky background in the 34mm might be more than you can tolerate. But on a good, dark night, objects such as the double cluster in Perseus are stunning in the 34mm.

Another option is a 30mm ep in a 1.25" barrel, which will keep the weight down. A surprisingly good eyepiece for budget cost is the Vixen NPL 30mm. I really like the one I had, it was extremely sharp across the whole field, however being a plossl the trade off is that it is only a 50deg field of view. But for low power sharp views in a 1.25" barrel it's extremely good.

Hope that helps a bit:-)


Dave

Hi Dave,

Thank you for your comment i do have a 40mm NPL vixen will his cancel out the 32mm?

Concerning my ES 24mm and Pentax I do find the stars are more like pinpoints and the detail with the moon and planets are slightly better with the Pentax then the ES.

Saying that I do enjoy using the ES for open clusters and observing the moon it's certainly a keeper ☺️

Richard

Link to comment
Share on other sites

8 hours ago, rockystar said:

who said anything about need!?!

Did you get out last night? it was beautiful, if a little bit bright, round our way.

Always good to have a full range of eps but I really don't think I need one now.

Unfortunately I'm working for the next 2 weeks solid almost holiday cover ?

Richard

Link to comment
Share on other sites

Hi Richard

I've not used the 40mm but I suspect it would have a narrower field of view than the 30mm. 

Optically I'd expect them to be similar, just a bit wider field and darker background due to the higher magnification with the 30  :-)..

Dave

Link to comment
Share on other sites

I reckon a 24mm 68 degree is as low as you should go in 1.25". Any longer and I would switch to 2", a 30mm 82 degree perhaps, will show far more sky and will be fab with dark conditions. As said, the sky background may be a bit bright if you have much LP.

Link to comment
Share on other sites

On 17 August 2016 at 23:27, Ricochet said:

Does anyone else find that the eye relief exceeds the eyecup height?

On a 32mm TV Plossl? The eye relief can be quite hard to get used to. On the TV you can buy eyeguard extenders which help cut out glare and make it easier to position your eye on the exit pupil.

http://www.televue.com/mobile/TV5_page.asp?id=158

You can also stack these on the 40mm, particularly useful if using in a Quark as its Barlow pushes the eye relief out even further.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.