Best high magnification EP for moon

[Highburymark]

Hi all.

Like many other urban dwellers, I spend a lot of time looking at the moon (through a Nexstar evo 6 inch), and I've just discovered the fascinating 'Lunar 100' list of targets by Michael Bird (can be found on the SGL Observing Lunar/Solar section) - which I'm going to try and tackle.

Currently my most powerful decent eyepiece is a 10mm Baader Hyperion which provides 150x, and I also have the 17.3mm Delos. What I really would appreciate is some advice on how far I could increase the magnification through my scope - while retaining pin sharp views of the moon - by adding a more powerful top quality EP, or a televue Barlow or powermate?

Ideally I'd like 300x , which would require a 5mm eyepiece, but not if the image deteriorates at such a high power. And are there EPs/brands that are particularly good for moon viewing? Thanks.

[michael.h.f.wilkinson]

Much depends on what you want to spend. I have the Vixen SLV 5 mm which is comfortable and excellent. I also have a few Pentax XW EPs (10 and 7). Superb EPs. In my C8 I can use a 5 mm on nights of good seeing, but the 10 and 7 get used a lot more. The SLV is optically similar in performance to the much more expensive XWs, except field of view.

[Mr Spock]

Given seeing conditions most nights you'd be better off with a 6mm giving x250. The SLV would fit perfectly with observing fine lunar detail.

[alan potts]

I think the answer from Mr Spock is logical,

Best high power is more often what the conditions will allow and not a specific number though you can push the envelope a bit on the Moon, quiet a lot really.

X250 I think will be excellent and I see a a nice 6mm Delos on Astro B&S which will deliver this.

[Highburymark]

thank you all - I won't cling on to the notion of a 5mm then.

[Mark at Beaufort]

The Lunar 100 list is very enjoyable and you may find this article produced by 'Doc' a helpful support. - http://stargazerslounge.com/topic/96159-the-lunar-100-by-doc/

I have used various scopes to view the Lunar 100 and the most pleasing sight of the Moon is with binoviewers. I have inexpensive Antares plossls (25mm and 17mm) and together with a barlow gives me fantastic 3D views of the Lunar surface.

If you want to stay with a single EP and considering you have a f10 SCT I would consider the Badder Hyperion zoom together with the Baader Hyperion Barlow. The Zoom with the barlow will be 3.5mm to 10.5mm so you dial the zoom to get the best mag for the seeing conditions.

[Highburymark]

Thanks Mark.

Interestingly I had the Pentax xf 6.5-19.5mm zoom to try recently, and was a little disappointed in the images at higher powers - despite being a fair bit more expensive than the Baader zoom. Seems like the Pentax is better for solar work and spotting scopes. I think the option for me now is to either get the Baader zoom and Barlow or as Alan suggested above, get a nice 6mm like a secondhand Delos.

[alan potts]

HighburyMark,

The only way to deal with temptation is to yeild to it! Oscar Wilde, go on get the Delos .

Alan

[Highburymark]

Thanks Alan.

We are all in the gutter, but those with Televue EPs are clearly looking at the stars.

[Highburymark]

.......and as OW also said, anyone who lives within their means suffers from a lack of imagination.

[alan potts]

The choice of Televue may well seem a lot of money now but I wasted a lot of money when I increased my collection with  faster scope. I got baerly 50% of the new cost of my Meade SWA and UWA eyepieces, though this was largely due to the problems they had coming and the selling of some  of their ranges as Maxvisions. There is also a school of thought that they were overpriced new.

In truth F 10 is fairly kind to eyepieces and you will get great enjoyment from many less expensive ones but never forget the value of the secondhand market and quality items, often you can buy and sell with little or no loss. That may well not be very good for manufacturers and traders but it is sure good for us.

Alan.

[ronin]

The reality is I suspect that you cannot pick an eyepiece, as in singular.

A 5mm may work once a year, even a 6mm is likely not to be usable every night, 250x is still high.

I would expect you to end up with 6mm and 8mm.

You have a few suggestions for 6mm, there are others like the 6mm WO Planetary that seems to come out good.

In the 8mm the simple TV Plossl will take a fair amount to beat it.

The one aspect of planetary and lunar observing is that you end up with lots of eyepieces in small increments.

Do not be surprised if you end up with 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm. :grin:

And if not 1mm increments then 2mm increments, 6mm, 8mm, 10mm, 12mm should be good.

[Mr Spock]

Yep, that's what you get, a huge range of eyepieces for planetary. In the range 13mm to 6mm I'm only missing an 11mm...

I mostly stick to x235 (10mm) with my C9.25 for Jupiter, with the moon taking x294 (8mm) most nights and maybe once a year x392 (6mm). So, even with 235mm of aperture, I won't use x300 on Jupiter as fine detail starts to lose contrast. With a 150mm you will start to loose contrast at lower powers than that.

I reckon for the moon you will be looking at a maximum of x250 as it a fairly contrasty target. Your x150 will already give the best ratio of contrast and sharpness for a 150mm scope so anything above that is just making things larger. You may well need something inbetween a 10mm and a 6mm.

[michael.h.f.wilkinson]

A 7 or 8mm might well be your best bet: sufficiently more magnification than the 10mm you have, but not so high that you would rarely use it. The Delos 8mm I have is superb, but the much cheaper Pentax XF8.5 is very good too (with 60 deg FOV, rather than 72). The new TV DeLites come in 7mm, but these are not available yet, I think

[nicoscy]

Or as a try-at-low-cost option is to get a 2' barlow for which you can use the element and thus get 1.5x barlow effect, turning your 10mm eyepiece into a 6.7mm and also as a 5mm eyepiece. If you feel the image quality is not up to par, the cost is low and you can experiment and see if you prefer something around 7mm or around 5mm.

[Ags]

Get some Baader fine tuning rings for your 10mm. This will give you very good EPs in the range of 6-8mm depending on the fine tuning ring:

http://agenaastro.com/baader-14mm-hyperion-finetuning-ring.html

Of course the cost is negligible and you can buy a dedicated EP in the focal ranges after you have tested the waters with the fine tuning rings.

I use fine tuning rings with my Hyperion 17mm, using it at 17 or 13mm for DSOs, and when Jupiter is well placed, I use it as a 9mm as my best 9mm EP. It is not so convenient to change the EP focal length by fine tuning rings, but if you know in advance how you are using the EP it can be very useful.

[Highburymark]

This is all fantastic advice - thank you all. Since getting back into astronomy at the start of the year I have never had so much fun working out how to empty my wallet. But I don't really spend money indulgently otherwise, bar the odd CD or so. Alright, the odd couple of thousand of CDs or so. So I don't feel too bad about building an EP collection that will last a lifetime.

[ronin]

Yep, that's what you get, a huge range of eyepieces for planetary. In the range 13mm to 6mm I'm only missing an 11mm...

So that just leaves the question: Have you ordered your 11mm TV plossl yet? :grin:

[michael.h.f.wilkinson]

So that just leaves the question: Have you ordered your 11mm TV plossl yet? :grin:

Or is he waiting for the TV DeLite 7mm

[LukeSkywatcher]

I use an 8mm Vixen NPL for all my lunar and planetary observing (if i am not using my 8-24mm zoom). With my 8" SCT that gives me something like 254x. Thats a comfortable level of magnification in this part of the world. I always think that the best magnification to aim for is the same as the aperture of the scope (in my case 200mm) and then a bit. Forget "useful magnification" of 400x etc as stated in the sales pitch for a scope.

[Highburymark]

Decent zoom is tempting - I've just been slightly put off by the Pentax XF 6.5mm-19.5mm. Not that it was bad in any way - but comparing it on the moon at 150x against my 10mm Hyperion, the Baader was sharper. Luke - how does your zoom compare at 8mm against your Vixen 8mm NPL?

[astromackem]

Or as a try-at-low-cost option is to get a 2' barlow for which you can use the element and thus get 1.5x barlow effect, turning your 10mm eyepiece into a 6.7mm and also as a 5mm eyepiece. If you feel the image quality is not up to par, the cost is low and you can experiment and see if you prefer something around 7mm or around 5mm.

What do you mean by using the element to get a 1.5x effect?

[nicoscy]

What do you mean by using the element to get a 1.5x effect?

This particular type of barlow from TS is quite useful. You can take just the bottom bit with the barlow element and screw it directly to an eyepiece 1.25'' thread and thus get a 1.5x barlow effect. Conversely, if you put the element on your diagonal, due to the increased distance between the element and the eyepiece you get roughly 3x barlow effect.

I am sure this barlow is sold in the UK under many other names and should be easy to find, otherwise TS does ship international.

[astromackem]

This particular type of barlow from TS is quite useful. You can take just the bottom bit with the barlow element and screw it directly to an eyepiece 1.25'' thread and thus get a 1.5x barlow effect. Conversely, if you put the element on your diagonal, due to the increased distance between the element and the eyepiece you get roughly 3x barlow effect.

I am sure this barlow is sold in the UK under many other names and should be easy to find, otherwise TS does ship international.

Thanks for that. I've found it on Amazon for £31. I'm not sure whether to go for it- for the different options or just by standalone eyepieces for better quality.