24mm ES82 or 30mm ES82

[Wardr77]

Hello all, I hope you will be able to help me with a purchasing decision I am about to make. I am currently looking to get either the 24 or 30mm ES 82deg eyepiece, but undecided which to get, though leaning towards the 24mm. The reason for the purchase is to improve the apparent FOV and gain a little on the true FOV. I mainly view DSO’s with an LX90 12” scope at F10 in a good dark sky area and my current go to EP is a standard 4000 Series 32mm Plossl which produces nice bright images. My concern is that the 24mm ES82 will noticeably ‘dim’ the images compared to the 32 Plossl, but provide a good FOV at a slightly higher mag. And with the 30mm ES82 although it will probably produce nice bright images the concern is that the thing is just so big and cause balancing issues  with the scope. What to do....? Any advice would be much appreciated.

Thanks in advance!

[rwilkey]

Hi Wardr77, I went for the 30mm and have never looked back, good sharp flat field in my f/9, a stunning ep.  Not tried the 24mm though.  I bought mine from AgenaAstro in the US when they were a bit cheaper and not readily available over here, so I am glad I took the gamble.  Brightness not diminished by the low power I have found.  You have to get your eye quite close to see all the view, however that is a trait of all the ES82's.

[damnut]

Hi There,

I had a 10"lx200, my favourite ep was a 80deg 30mm. I prefered it over the Axiom 23mm purely for the reduced power.

Both of the ep's you are looking at are at the quality end of the market. You would be delighted with either, but my vote would follow Robin, go for the 30mm.

[alan potts]

I have had the pair of these but under the Meade flag. If you have a dark site I would go for the 30mm, I have used this in a scope with the same optics as yours and it works well. I would be a bit concerned about the weight though without a counterbalance system, I have one on my SC 12 inch scope but I have another scope mounted on top as well. One thing Meade do not tell you is how much one can load on the back without causing any long tern issues with the motors.

The other option you could consider is the F6.3 Focal Reducer and the 24mm, this works without vignette and gives you about the widest field you can get from this scope, the 28mm SWA also works with the FR without vignetting, this is about you absolute limit, I have tried all of these combinations.

Alan

[michael.h.f.wilkinson]

I use 31mm Nagler in my F/10 8" SCT, and never have balance issues. A 12" should shrug these off. Ulitmately, you want both EPs, just like I have a 31mm and a 22mm Nagler. The 31mm gives great wide-field views, the 22 is the better galaxy hunter.

[Wardr77]

Thank you all very much for your responses, most helpful. It appears the 30mm is the preferred option. My scope is very much nose heavy even with the standard diagonal and 4000 ep attached; I have to really tighten the clutch to stop the scope from dipping (another concern), I guess Meade engineered it this way to compensate for higher loads at the back. Interesting point with the FR. I thought about this, but got confused when I saw a lot of contradictory information relating to the meade 6.3 FR with coma correction and ACF optical systems... I'll leave that one for later I think!

Just out of interest for those who have both the 30mm and 24mm, is the 24mm image noticeably dimmer?

Thanks again.

[alan potts]

I really don't think so after all a 12 inch is a large collecting surface. I don't really notice anything start to dim to any degree until I am over X200. I think there is a strong case in time for both or as Michael mentioned something around 22mm though to the best of my knowledge that means TeleVue in 82 degree FOV.

Alan

[Wardr77]

Well I've just performed a highly scientific test regarding weight off the back of the scope. By putting a can of beans, a can of chopped tomatoes, a can of peas and a can of sausages and beans in a small bathroom bag I got a total weight of 1.515kgs, I hung this off the back of the scope and gently released the dec clutch. The scope still fell forwards from the horizontal but slowly, so pretty well balanced. I think therefore a 30mm and diagonal will be a pretty good match for this scope weight wise!

[YKSE]

I agree with Michael, 31mm is my starting eyepiece in my SCT too, in my dark site, it'll mostly like be one to find the faint galaxies too, for some galaxies or nebulae with very low surface brightness, I've had to use 40mm eyepiece too. Eyepieces around 20mm(2mm exit pupil) are much more useful in hunting faint fuzzies with better surface brightness and smaller size.

[Wardr77]

Well after some 'issues' in the sourcing of the EP I finally received the 30mm 82mm last week. What a thing! That is one big EP! But the views were seriously good, I now understand what is meant by a space walk! The clarity and brightness across the field was astounding and the seeing was not that great either, so all in all very pleased. It was an odd sensation to move your head about a bit to see all thats out there, I can only imagine what the 120 deg EPs must be like, probably feels like you need to crawl inside them.

My scope however is not as balanced as I thought it would be. I neglected a couple of important factors during my testing, namely not attaching the finder and leaving the lens cap on! With these attached and removed, the result is a rear heavy scope, not as bad as the front heavy position when using the standard 1.25 diagonal and ep but still significant, so will probably look to invest in a counterbalance setup next.

[kurtz9]

If the scope is now slightly rear heavy, but less so than it was previously front heavy and worked fine, I doubt you'll have any issue.

BTW if you decide you want higher magnification in the future let me recommend the ES-100 degree in 20mm, it's the most reasonably priced of the 100 degree series (actually slightly cheaper than the 30mm 82) and produces excellent views in my 9.25" F/10

[Mrbloke]

BTW if you decide you want higher magnification in the future let me recommend the ES-100 degree in 20mm, it's the most reasonably priced of the 100 degree series (actually slightly cheaper than the 30mm 82) and produces excellent views in my 9.25" F/10

Alas not for us in the UK or Europe there's a good £120 difference between the two.

[Wardr77]

The scope has performed fine despite the inbalance, but I'm a little concerned about the longer term effects on the motors, particularly DEC.

How do you find the 100 deg EP? Do you find you have to bury your eye into the EP to get the full effect?

[John]

I've owned a 20mm Explore Scientific 100 degree eyepiece. It's a really good eyepiece. A noted reviewer in the USA described it as being like a 100 degree Nagler, which I would agree with. To see the full field of view and get the full "immersive" effect I found I needed to observe with the rubber eyecup rolled down. I don't wear glasses when observing and I reckon those that do might struggle to see the full field even with the eye cup rolled down. Very impressive eyepiece though.

[kurtz9]

The scope has performed fine despite the inbalance, but I'm a little concerned about the longer term effects on the motors, particularly DEC.

How do you find the 100 deg EP? Do you find you have to bury your eye into the EP to get the full effect?

I find it to be excellent... I do find if you want to see the very edges of the field you need to move your eyeball around some, but haven't had the need to get close enough that I brush my lashes on the top of the lens or anything....and that's with the eyecup UP (ie I didn't need to roll it down)

The fact the field stop isn't obvious looking dead on is one of the things that really contributes to feeling like you're doing the spacewalk thing rather than just looking through a little piece of glass

I expect folks with glasses or different vision than mine will get varying results of course- I know I've seen some folks (like John) mention needing to roll the eyecup down to see it all for example.

Eye relief is 14.5mm if that helps you any...it also turns into a nice 100 degree AFOV 10mm EP in the ES 2" focal extender, with no change to the eye relief.

Alas not for us in the UK or Europe there's a good £120 difference between the two.

That's really weird... given they're from the same company I would expect their price relative to each other at least would be the same everywhere.... (for reference in the recent sale you could get the ES82-30mm for $315, on sale from $339.... and the ES100-20mm was on sale for $279, down from $329 regular price)

[jetstream]

The 30mm ES 82 is an excellent eyepiece and is a bargain for the price (here anyway). In your F10 the 3mm exit pupil will make a great DSO finder eyepiece among other things. The large fs diameter is a very nice feature of this EP as well as the waterproof design. Enjoy!

[John]

These big, heavy eyepieces get even bigger and heavier in a 2" TeleXtender / Focal Extender / Powermate though

[triton1]

You could bang your head on that John.

[kurtz9]

That's one of the best parts-  The weight of the big EPs with a focal extender lets me move my C9.25 far enough forward on the dovetail that the big 2" diagonal clears the base going to zenith

Plus it's much harder to misplace huge eyepieces or have em slip from your fingers since you need to hold em with your whole hand!

[Paul73]

Hi

I have both in my "most used" case. Both great eyepieces.

If you want wide. Go for the 30mm. You would not notice any dimming of view between the two with your scope.

If I only had one. With your scope. I would take the 30mm every time.

For my F4.7 scope so it needs to be properly dark for the 30mm to really fly. You should be fine.

Paul

Ps. As others have written. The 30mm will certainly sort out any "front end heavy" issues that you might have.....

[alan potts]

I like large eyepieces very much, I do have a few and have owned a good few more from other makers. The only downside I find of using them and one reason why I didn't like the Powermate tower is the slightly suspect focusers in some scopes or visual backs.

Meade 2 inch visual back, before I put the Moonlite on the SC this let diagonals and heavy eyepiece slip round 3 times. Lucky they never fell out of the diagonal, that being TV is very well made.

The same visual back now on the Mak 180mm has also sent the 35mm Panoptic spinning twice and a 21mm Ethos, again the diagonal held fast. The visual back that came with the Mak came unscrewed with the weight of a 24mm UWA, again it didn't fall but the visual back took a trip to the dustbin it was utter rubbish.

Any very large eyepiece in the focuser of my M/N 190mm induces a slight bend due to weight, many of these eyepieces have to used with an extention sleeve, it is not a serious misalignment but I can see it in the edge views, it never has a problem with the T6 range of Naglers and never did on other smaller Meades .

I find as much as I like it the 31mm Nagler it can also induce a slight bend the Paracorr Mk1 if it is not really tightened in the Sumerian though the Moonlite there is solid and unmoving. I can't say that I can see the effect though.

I wonder what the 3 inch 30mm 100 degree would do to a scope, if indeed you could fit one.