Your One Choice EP

[Freff]

I have been given £70+ to buy a single EP for our SW 127 SkyMax GoTo. We (the kids and I) have only the kit EP's and would like to add another to enhance our viewing. ( planetary generally)

I have read through countless threads and it's a minefield to to come to a decision.

I sure you are all feed up with these "another EP thread", but honestly It's really painfull when you have no clear understanding.

Many thanks

Tony

mods please move to Beginners Help & Advice

[Bigwings]

Hi The Skymax 127 at f11.8 is not going to be hyperfussy about EPs.

I would go for something like Revelation EP,s. I use them on my f10 (but I have gone 2") and they are fine. Not good in a fast DOB but for you and me and many in the slow brigade we can forget the state of art hyperexpensive stuff. You need to decide on what its for....planets...big DSO , small DSO as this will help. If your lucky you could pick up a second hand Revelation set for not much more than your budget.

Clear Skies

Mike

[shaunster]

What about a william optics SPL?

or

How about a TV plossl?

Nice to add some green to the collection

[LukeSkywatcher]

A second hand zoom EP perhaps?

[Steve]

Here are a handful of focal lengths (6, 10, 17 and 25mm Plossls) to help you visualise the differences.

[Mr Spock]

9mm Baader Orthoscopic. That would be my choice for planetary work.

[spaceboy]

TMB Clone without boubt £38 delivered so you could break open the piggy bank and get two

[Steve]

Aaah .. Planets. Here is another that might be more relevant (the 6mm's larger field of view makes it look similar to the 9mm).

HTH

[Moonshane]

Can you confirm a couple of things first?

Do you wear spectacles to observe at the eyepiece?

Is the mount a tracking mount?

What EPs do you have currently and do you have a decent barlow?

With this we could possibly advise a bit more positively. There are lots of options within your budget and as others have said your scope is not too fussy either.

[Wurzil]

another shout for a tmb clone. a TS planetary HR from modern astronomy or a tmb clone from skysunlimited items - Get great deals on 1.25 Eyepieces, Telescope Accessories items on eBay.co.uk Shops!

I wouldnt bother splashing out on a short focal length tv plossl for the skymax; although they are nice solid eyepieces that will hold their own in any scope, they arent as comfortable to use as the tmb clones, have less eye relief, a smaller eyelens and a narrower fov.

I love my TS planetary hr 5mm ep:)

w

[Freff]

Can you confirm a couple of things first?

Do you wear spectacles to observe at the eyepiece?

Is the mount a tracking mount?

What EPs do you have currently and do you have a decent barlow?

With this we could possibly advise a bit more positively. There are lots of options within your budget and as others have said your scope is not too fussy either.

Hi

No I don't wear specs to observe.

SynScan™ AZ GoTo Computerised Alt-Azimuth HD Go-To Mount

10mm & 25mm kit EP's and kit Barlow.

Thanks

Tony

[Moonshane]

cheers Tony

sorry - I didn't spot your signature!

as you say your main targets for this EP will be planets (and presumably double stars and moon too) then you really don't need a wide field.

I think I might be correct that the 10mm EP you get with the scope is quite poor and the 25mm quite good? Assuming the 25mm Barlows OK and ignoring the 10mm you have :

25mm = 60x

12.5mm (25mm with barlow) = 120x

using my own usual calculation of 1.5 x aperture in mm you can feasibly get about 200x most of the time with your scope in good conditions.

This equates to a 15mm eyepiece (100x) which would barlow to 7.5mm (200x).

Using this logic, I'd suggest a 15mm TV Plossl which you can get for £56 new at the minute. This has decent eye relief, excellent optics and can be used in most scopes to f4 so if you get a faster scope with more aperture it will be good in that too.

The other option would be the TMBs or the BST Discoveries from skies the limit on ebay I preferred the latter. For £38 delivered each (I think) you could get an 18mm (83x and 166x) and maybe an 8mm (187x and 375x) although I doubt you'd ever barlow the 8mm except rarely on the moon.

With the 25mm, the 18mm, maybe the 10mm and the 8mm, you'd possibly not use the barlow so if it's not great then this would make it not totally required?

Hope this helps.

Cheers and good luck - anyway off out now as it's clear for a change!

[Freff]

Hi Moonshane

Many thanks for that great info. I have been hovering around this site TeleVue Plossl Eyepieces (not heard of it before ) at the very same TV 15mm @ £67.

Next year we were hoping to get a SW 200PD or 250PDS on a EQ6 Pro so that EP will be ok on that as well.

Thanks again for that, I have quite a bit specifically to go on with now.

Tony

[Moonshane]

Green-witch are very reliable and quick but Telescope House (same applies) have them at 10% off

TeleVue 15mm Plossl Eyepiece 1.25"

[Freff]

That's great news, I'll send off for one tomorrow.

Many thanks to all for your replies.

Tony

[LukeSkywatcher]

I know TV are regarded as one of the best makes and people swear by them but i dont like the look of them. They look cheap (i know they aint).

I prefer my EP's to look and feel like this: Big and chunky and heavy.

[sixela]

The 15mm TV is a good bet, but then I'd add a barlow too (e.g. a Tal 2x barlow). That way you'll get tons of other eyepieces!

[LukeSkywatcher]

The thing about Barlows is to make sure if you are going to buy one that you are not doubling up your EP collection.

What i mean is that if you have a 10mm and a 20mm EP. A 2X barlow will give you ANOTHER 10mm EP. You then have a 5mm,10mm,10mm and a 20mm.

[sixela]

Well, it does give you two 10mm eyepieces, but one of them will be a lot more comfortable than the other and likely better, too. On my "vacation scope" when I was silly enough not to want to travel with my preciousss stuff, I had a combo like that, and I preferred the barlowed 20mm to the 10mm a lot. I only used the 10mm in the barlow.

The only drawback of a good barlow is it's fussy in use.

[LukeSkywatcher]

You are right. A barlowed 20mm and an unbarlowed 10mm do give a different experience.

I also have a "vacation" scope and this year i took it with me with a 10mm and 20mm EP and my TAL 2X barlow. I preferred the 20mm+barlow views. I think this was more to do with the tripod and the fact that the scope doesnt work too well with higher magnifications because of the flimsy tripod.

So i retract my comment about not buying a barlow if it is only going to give you 2 similar size EP's.

The views with and without a barlow are different.

[russ]

TMB Clone without boubt £38 delivered so you could break open the piggy bank and get two

That would be my suggestion too

[sixela]

using my own usual calculation of 1.5 x aperture in mm

Personally, unless you have bucketloads of floaters in the eye, I don't think this "rule" is actually that hard. That rule is ok for 200-250mm scopes but on larger scopes you'll tend to use slightly less and on smaller scopes (where the seeing tends to limit the magnification less as the scope's limits are lower) I tend to use 1.8x as a guide.

But yes, if you do't have that "1.5x" eyepiece you should still get that first. That's why we both agree a barlowed 15mm eyepiece makes a lot of sense.

On a side note, I would mention the 16mm Meade 5000 SWA; there are still a couple left in Germany at killer prices, though still out of budget (certainly if you have to add a 2x Tal barlow for "general planetary" work).

I don't diagree that for "general planetary work" there's little need for a wide field, but I mention it because a wide field eyepiece might transform this scope into something else than just a "general planetary" scope. It's a bit of a chicken-and-egg thing. If you have light pollution, you usually select DSOs that are still good for the scope and then want more magnification than the 25mm but not less field of view.

So if you only have Plössls, you can't see anything in the 25mm Plössl because of the light background, you can't see anything in the 10mm Plössl because the field of view is small and it's already too much magnification, and so what's left to observe well are planets. Getting a 15mm Plössl will simply leave you in the corner your current eyepieces have painted you (which is fine if you don't care about DSOs at all, obviously).

With a 16mm widefield, you can combine a slightly darker background with a large field of view for open clusters, and with a barlow start hunting some bright but small planetaries and globular clusters. So that widens your perspective a bit. And you can still use it for planets too.

Which doesn't mean I'm pushing it very hard; I just want all options to be on the table, even the slightly less obvious ones.

[nightfisher]

That would be my suggestion too

I might have to look at getting a couple of these for my omc-140

[John]

That would be my suggestion too

Another vote for a TMB planetary clone here - orthos's are great but I note that this is for family use so you want something that is "friendly" and the longer eye relief and wider field of view of the TMB planetary clones delivers that IMHO.

[russ]

I might have to look at getting a couple of these for my omc-140

Only slight snag with the OMC will be the focal length of 2000mm. This means all the original range of TMB Planetary sizes will be operating at well above 200x, which may not prove that useful.

They have added low powered eyepieces to the range, all the way down to 25mm. But these weren't part of the original TMB range and i have no idea if they are even the same design eyepiece internally (has the same external clothes but lens arrangement could be different). It could be that the 12mm, 15mm, 18mm and 25mm are what were going to be the TMB Stellar range but only a 20mm was ever released.