Aero ED's impress

[John]

Over the past 6 months or so I picked up a couple of the Aero ED style 2 inch eyepieces. The 40mm, which is actually branded as a "SKy Rover" but is clearly the same eyepiece and the 30mm which is an actual Skywatcher Aero ED I believe.

I reported on the 30mm some time back (where did those 10 years go ?!!)

SW_Aero_30mm02-09.pdf

So it has been interesting trying that one again and finding out how the 40mm fares.

This is not any sort of in depth review but generally I've found these eyepieces very competant and likeable performers in all my scopes from F/9.2 to F/5.3 in focal ratio. The 40mm is the better corrected of the two at the edges of the field of view but both do a good job over most of their 68 degree fields, even at F/5.3.

What is interesting about them is that their correction remains consistent regardless of the focal ratio of the scope. I've not come across that before with eyepieces - generally an eyepiece that starts to show astigmatic stars at the field edge in, say, an F/7 scope shows this to a noticably greater extent in faster focal ratio scopes but not so with these 6 element eyepieces. I see that I found something similar with the 30mm a decade ago so it is good to see that the 40mm shares this and that my observations now are consistent.  

Nice and light too, for 2 inch wide angle eyepieces so dobsonian balance is much less impacted. Not perfect eyepieces in every way but they seem to have high levels of light transmission and are comfortable to use. They are priced at around £100 apiece new but both of mine are pre-owned so were quite a bit less expensive.

Rumoured to share the same optical layout as the celebrated but long out of production TMB Paragons but I don't have one of those handy for a direct comparison.

I like this eyepiece design

[Geoff Barnes]

Those eye lenses look very deeply recessed John, how did you find the rye relief?

[John]

25 minutes ago, Geoff Barnes said:

Those eye lenses look very deeply recessed John, how did you find the rye relief?

I have the eye cups twisted right up Geoff. The eye lens is still recessed when they are down though. I find the eye relief entirely comfortable but I don't wear glasses to observe.

The quoted eye relief is 16.7mm for the 30mm and a little less for the 40mm. I find them both very comfortable to use even with the eye cup in the "up" position but "Your Mileage May Vary" as the saying goes

 

[Alfian]

I'm pleased you've highlighted the Skyrover John and that you rate it. I have the Rigel Skyrover 35mm which I've used in my ED100 and have been very pleased with it. Having now sold the ED100 I have no proper use for the EP and have tried to sell it. Even after reducing it twice I didn't get any takers. The idea of "clone" EPs is a familiar one but perhaps the unfamiliar Rigel name makes people cautious.

[rhw1967]

11 minutes ago, Alfian said:

I'm pleased you've highlighted the Skyrover John and that you rate it. I have the Rigel Skyrover 35mm which I've used in my ED100 and have been very pleased with it. Having now sold the ED100 I have no proper use for the EP and have tried to sell it. Even after reducing it twice I didn't get any takers. The idea of "clone" EPs is a familiar one but perhaps the unfamiliar Rigel name makes people cautious.

Being fairly new to Astronomy, I would love someone to tell me what a clone is. I assume it's a copy, or is that too simplistic  ? And does that also mean that the clone doesn't have the same standard as the original ?

I am assuming the answer to that more complicated than I think though.

Asking this because I had been looking at Aero EDs.

[Alfian]

My understanding, and use in this instance, of the term "clone" is where an eyepiece is produced by a factory but carries different badges according to which supplier markets it. The well regarded Starguider EP can be found in various other guises and seems to be of evenly good quality. However there are instances, and the TMB planetary range springs to mind where the "clones" of the original design do reputedly vary in quality so perhaps  using the term "clone" is a bit simplistic.

 

[rhw1967]

Ah, ok, thanks for that... Had seen references about badges and suppliers "versions", and now you have explained it I understand what they are now 

Cheers 

[Jarvo]

Mesmerised by the sea of green in the background..................

[John]

With a lot of astro products, the manufacture happens in the far east and then is ordered, branded and retailed by a variety of companies. Sometimes the body design alters but the optics are the same. It can be quite confusing knowing what you are getting, especially if there is a wide difference in pricing, which there sometimes is.

 

 

 

[Louis D]

4 hours ago, John said:

With a lot of astro products, the manufacture happens in the far east and then is ordered, branded and retailed by a variety of companies. Sometimes the body design alters but the optics are the same. It can be quite confusing knowing what you are getting, especially if there is a wide difference in pricing, which there sometimes is.

Like that Surplus Shed zoom I picked up.  It greatly resembles the one you like to use with a barlow lens, yet it seems to have characteristics different from yours.  Likely from the same Chinese source(s), but with some variations in the design.

On 30/01/2019 at 19:53, John said:

I have the eye cups twisted right up Geoff. The eye lens is still recessed when they are down though. I find the eye relief entirely comfortable but I don't wear glasses to observe.

The quoted eye relief is 16.7mm for the 30mm and a little less for the 40mm. I find them both very comfortable to use even with the eye cup in the "up" position but "Your Mileage May Vary" as the saying goes 

Is the 40mm usable with eyeglasses with the eye cup all the way down?  If it starts out with 16mm or so of design ER and then the recess is subtracted, it might have around 11mm to 12mm of usable eye relief.

[John]

6 hours ago, Louis D said:

...Is the 40mm usable with eyeglasses with the eye cup all the way down?  If it starts out with 16mm or so of design ER and then the recess is subtracted, it might have around 11mm to 12mm of usable eye relief.

Not wearing eye glasses, it's difficult to tell.

Eye relief has never been a big issue in of itself for me so as long as I find the eyepiece comfortable and I can see the full AFoV easily thats good enough and I concentrate more on the view.

This was more of a casual report than a detailed analysis of the things. I like using them, they perform well to my eye and they don't cost an arm and a leg to acquire

 

[bingevader]

Apparently, the coatings can sometimes differ between clones too.

John, as you say in your original review, it would be good to put these up against the Panaviews.

For the extra £25 or so, I'm assuming these would perform slightly better than the Panaview?

I have my ES82° 30mm now which is rather splendid, but I never much minded the seagulls in the Panaview.

And, as a relatively inexpensive entry into 2" wider field views, for the price, the Panaview is pretty damn good!

I'd be tempted by Aero though with some extra savings.

[F15Rules]

On 01/02/2019 at 10:03, bingevader said:

Apparently, the coatings can sometimes differ between clones too.

John, as you say in your original review, it would be good to put these up against the Panaviews.

For the extra £25 or so, I'm assuming these would perform slightly better than the Panaview?

I have my ES82° 30mm now which is rather splendid, but I never much minded the seagulls in the Panaview.

And, as a relatively inexpensive entry into 2" wider field views, for the price, the Panaview is pretty damn good!

I'd be tempted by Aero though with some extra savings.

Hi Bingvader,

I've owned the Panaview 32mm and the Aero/TS Optics 30mm and 40mm..(I still have the 30mm Aero.

As you say, the Panaview is a decent entry into 2" wide field viewing.  However, they are heavy units and poorly corrected at the edge of the field. Also, DON'T unscrew the 2" bottom barrel without extreme care as this barrel is all that stops the lens assembly from falling out!

The Aero is lighter, more comfortable and much better corrected at the edge. Aero/Sky Rover/Rigel etc -they are all optically the same, ie excellent for the money..?

You can pick these up for between £50 and £75 used (very little more than a used Panaview) - I paid I believe c £60 posted for my 30mm☺, and my newer 40mm went for c £70.. I personally prefer the 30mm with its darker sky background but both are excellent eyepieces.

There is a 40mm for sale on here by @Ipeace (Mike) - a top guy and 100% trustworthy seller.

Dave

[John]

I agree with Dave (not for the 1st time ! )

[bingevader]

Thanks Dave!

Very helpful.

[pregulla]

On 01/02/2019 at 05:03, Louis D said:

Is the 40mm usable with eyeglasses with the eye cup all the way down?  If it starts out with 16mm or so of design ER and then the recess is subtracted, it might have around 11mm to 12mm of usable eye relief. 

According to this post (in Russian) it has measured ER of 17mm from the lens or 8mm from the top of folded eye cup.

[John]

36 minutes ago, pregulla said:

According to this post (in Russian) it has measured ER of 17mm from the lens or 8mm from the top of folded eye cup.

They seem to have more useable eye relief than 8mm to me - I have a number of eyepieces with 10mm of eye relief and the Aero ED's are more comfortable than those

[pregulla]

Maybe large exit pupil makes eye placement easier or maybe the eye-cup design. Maybe the eyepieces you are talking about have shorter practical ER or maybe the Levenhuks have shorter ER than SW Aero.

[John]

42 minutes ago, pregulla said:

Maybe large exit pupil makes eye placement easier or maybe the eye-cup design. Maybe the eyepieces you are talking about have shorter practical ER or maybe the Levenhuks have shorter ER than SW Aero.

Maybe to all !

 

[Louis D]

6 hours ago, John said:

They seem to have more useable eye relief than 8mm to me - I have a number of eyepieces with 10mm of eye relief and the Aero ED's are more comfortable than those

I've had the same experience where I've measured the eye relief via projection only to find out it doesn't match the "feels like" eye relief.  This works both ways, though.  Some measure longer and feel shorter while others measure shorter but feel longer.  I've never been able to nail down the cause, but contributors include the diameter of the eye cup which can affect how far a curved eyeglass lens can protrude below the rim (think the giant rim of the ES-92 line and 35mm Baader Scopos Extreme) and chromatic aberration of the exit pupil where blue and red can focus 2mm or more apart (think original mushroom topped 30mm ES-82) allowing the user to see a sharp image at one or the other end of the spectrum of visible light.

I think I'll still take a pass on the 40mm Aero ED unless it comes up really cheap second hand.

[John]

I think I'm done with these deep analysis and measurement of eyepieces these days. If I look though them and like what I see I'll use them

Perhaps I'm less picky now

[iPeace]

24 minutes ago, John said:

If I look though them and like what I see I'll use them

Works for me. But that still leaves so many of them....!

[Pig]

9 hours ago, iPeace said:

Works for me. But that still leaves so many of them....!

Your name sums it up ?

[Louis D]

Based on @John's reviews and Ernest's measurements, I picked up a 35mm ED to try as a light weight, widest field eyepiece for a 127mm Mak.  I'm still trying to figure it out, but it views narrower in AFOV in the Mak with a fuzzy field stop than in the 72ED with a sharp field stop.  I can easily take in the entire field of view in the Mak with eyeglasses because it appears to be 60 degrees or less wide.  In the 72ED, it looks to easily be the 70 degrees measured by Ernest, but I can't take it all in at once with eyeglasses thanks to the eye lens's recession.  I can't tell yet if I'm seeing field cutoff due to the Mak's small rear port.  The 40mm Meade 5000 Plossl doesn't suffer any ill effects from the rear port.  It still has a 60 degree field with a sharp field stop.

It definitely performs better at f/12 in the Mak than at f/6 in the frac.  The center is sharp for both, but it gets astigmatic more quickly in the frac and is much worse at the edge in the frac.  At least it's fairly flat of field.  Refocusing the edge didn't improve matters in either scope.  It's pretty much equivalent to the Meade in terms of TFOV, sharpness of field, and onset of astigmatism.  The most remarkable finding was that the 30mm 80 degree Widescan III clone was perhaps sharper in the center than the 35mm ED and showed less edge astigmatism.  Once again, it needs a field flattener, though at f/12, the refocusing was very minor.  After refocusing for the edge, the Trapezium was still splitting at the field stop with just the right head tilt to align my eye's optical axis with the incoming edge rays.  By comparison, the Trap was an astigmatic mess in both the ED and Meade at the field stop no matter what tricks I tried to clean them up.  The 80 WS clone also had a more pleasing 70 to 80 degree field (not sure if it was showing cutoff as well) that was super comfy to take in with eyeglasses.  That eyepiece just needs a field flattener ahead of its field stop to become a real contender in slower scopes.

I'll have to do more comparisons, but right now, it doesn't look like the 35mm ED is knocking the 40mm Meade or 30mm WS III clone off their perches in my kit as lightweight, widest field eyepieces with acceptable field aberrations at f/12 and yet are still comfortable with eyeglasses.

I gave up looking for the 40mm ED because no one has them new, and they get snatched up too quickly on the used market at too high a price.  Based on my experience with the 35mm, the 40mm might be slightly better at the edge and have slightly better eye relief, but still not comfortable with eyeglasses compared to the Meade or WS III.

I'll have to try it in my 8" Dob next, but there really is no use case there since it doesn't mind heavy eyepieces.  I compared the 35mm ED to the 35mm Baader Scopos Extreme in both the frac and Mak, and the BSE blew away the ED in all categories except TFOV where the ED won by a slight margin.  The BSE is sharper across the field and shows little to no astigmatism at the edge even in the frac.  It's also very comfortable with eyeglasses and shows a decent, though not razor sharp, field stop.  The BSE is over three times heavier and about twice as wide as the ED, so the poor frac and Mak kept getting thrown off balance at high elevations as when viewing the moon last night, and the frac's focuser kept slipping, so it's more or less useless with them for serious observing.

[John]

I've never tried the 35mm in this series. The 30mm is not quite as well corrected in faster scopes as as the 40mm I've noticed that. Sounds like I'll continue to give the 35mm a miss. Not that I need that focal length. 

I was using the 30mm with my ED102 F/6.5 at an urban outreach event last night and the views were lovely. The 4 Trapezium stars very crisp amongst the nebulosity even though the magnification was only 22x.

Based on a combination of mine and your experiences Louis, looks like the ranking of the 3 focal lengths in terms of overall quality would be:

1st: 40mm

2nd: 30mm

3rd: 35mm

And there we have it