ES 62 for st80

[mark81]

Hi all

So I was reading some old threads about EPs for the ST80 and a number of people mentioned that they only use two - or in some cases just one EP for this scope.  My EP selection is quite poor at the moment,  two EPs that came with it, a donated 6.3 plossl and a 15mm BST - which I like... But I seem to spend half my time switching from one to the other and never getting anywhere as the quality differs so much between them. So on my way to buying maybe two decent EPs I wondered if these would suit my st80 and then which size to go for.  

https://www.firstlightoptics.com/explore-scientific-eyepieces/explore-scientific-62-series-ler-eyepieces.html

Any thoughts or comments very welcome ?

[happy-kat]

Are you thinking of a new higher powered one, I wonder if an ED eyepiece would be an idea for the ST80. Also eye relief for me is a bit tight on the higher powered ones. I've been fortunate picking up nice eyepieces on here in the for sale section, if you subscribe to that section you'll get notifications on all sorts.

[mark81]

I think I'm looking for one low power maybe around 25mm and one medium power - say around 5-10mm...

[happy-kat]

The Vixen NPL 30mm comes up from time to time on here for a very good price. It is a nice little eyepiece.

Do you want all the same or are happy to mix and match and not have par focal eyepieces?

[mark81]

25 minutes ago, happy-kat said:

The Vixen NPL 30mm comes up from time to time on here for a very good price. It is a nice little eyepiece.

Do you want all the same or are happy to mix and match and not have par focal eyepieces?

I would prefer the same.  I will have a read about the NPL, thanks

[happy-kat]

I am not sure if I would get a high powered NPL I only have the 30mm, hence I wondered if you like all the same or not as I have been going for a mix of everything.

[Ricochet]

2 hours ago, mark81 said:

But I seem to spend half my time switching from one to the other and never getting anywhere as the quality differs so much between them.

Can you expand on what you mean by this? Are you looking to keep using any of your existing EPs in conjunction with the new ones? Judging by the post quoted below I would guess you would keep the Starguider but not the others?

2 hours ago, mark81 said:

I think I'm looking for one low power maybe around 25mm and one medium power - say around 5-10mm...

I would consider a 5mm eyepiece as high power for an ST80. As it is a fast achromat the CA will get in the way at high powers and it will be best at low power, wide field views. With that in mind the first thing I would do would be to maximise the field of view that the 1.25" focuser can provide. My choice for this would be a 24mm 68° eyepiece (i.e the Explore Scientific or Maxvision/Meade SWA variants). If the price of one of those is too steep then the 26mm 62° is probably a decent alternative, although I think the edge correction will not be so good.

Long term I would consider roughly 5 - 7 - 10 - 15 - 24 as a complete set. Adding a 10mm and 2x barlow would suffice. If the ES62° eyepieces are at the limit of your budget then I would consider the 10mm Baader Classic Ortho if you do not need glasses and eye relief is not a major concern.

[happy-kat]

I didn't suggest the maxvision 24mm as although it gets great reviews (I really like my 16mm) I thought on an ST80 it would be very big and heavy it is a heck of an eyepiece in size. I appreciate it does give the same fov as a typical 32mm but with more magnification. However given the great price they go for second hand it could be worth a try to pick one up.

[happy-kat]

A maxvision 24mm only sold just over a week ago for £45 picture here Link to add

[parallaxerr]

I use ES68°s with my ST80, specifically the 24mm and 16mm. The 24mm is nice, but, can give a washed out view if there's any LP about due to the 5mm exit pupil. I find the 16mm FAR better in this respect. The background sky is darker but with a 3.2mm exit pupil, I can still pull out DSOs such as M27, M31 & M57 etc.

I often try my ES82° 11mm for more image scale, but the image gets a bit dim and I invariably drop back to the 16mm.

It's really hard to recommend eyepiece focal lengths to other people because there are so many variables. It also depends on what targets you want to view, but bear in mind that the ST80 is no high power scope, it is generally used for low power wide field viewing. Personally I would not consider EP's below 10mm in the ST80, unless maybe looking at the moon.

I'd suggest going for the 20mm to start with and see how you get on, then make your next purchase decision based on whether you want more field of view or more magnification. If you could have only one, I don't think you'd go far wrong with the 14mm, based on my experience, but you'll probably find those others who use only one EP use a 24mm+ for maximum FoV, which is fine if you have dark skies.

This is what Clear Skies forecast has to say about my skies, where I find the 24mm a bit washed out...

[Louis D]

18 hours ago, mark81 said:

So I was reading some old threads about EPs for the ST80 and a number of people mentioned that they only use two - or in some cases just one EP for this scope.

I wonder if I was one of those two eyepiece folks.  When I took my old ST80 up to Nebraska for the eclipse, I only took along a 32mm GSO Plossl for widest field views to center the sun and an 8-24mm Celestron Regal zoom to observe with.  The zoom was very handy during the 2.5 minutes of totality to zoom in and out quickly to perfectly frame the corona.