Best ep for planetary viewing.

[Daz Type-R]

Hi all,

As the title suggests, what is the best ep for planetary viewing?

One stipulation, it has to be Televue!

I find the the eye relief on TeleVue ep's to be excellent and is a very big factor for me when choosing ep's.  I`ve had ep's in the past where the eye relief was small, it was awful for me.

I have been looking at the Delos range, around the 6 to 8mm range, to be used in my F6 reflector.

Any other ideas, for planetary use only.

Cheers.

[faulksy]

i was going to suggest orthos but if tv ten delos, or radians. stu is selling some great eps at the moment in the focal length your after, there in the classified now

[Pig]

Is a 200p a 1000mm focal length ?  If so I would go for a 6mm Delos 

[Daz Type-R]

Is a 200p a 1000mm focal length ?  If so I would go for a 6mm Delos 

They come in 2 flavors, if you buy a 200P on a EQ mount as part of a package then the focal length is 1000mm but if you buy the 200P on the Dob base, then they are 1200mm focal length.

[ronin]

He did say f/6 reflector, sig says 200P, combined that suggests the 1200mm variety. :cool:

[alan potts]

There is a very nice 6mm Radian on the classified site by BigMakStuov, I would buy it if in the UK. The 6mm Radian is a very good planetary eyepiece and grossly under-rated by many. I have owned the 6mm and know how good it is.

Alan

[Daz Type-R]

There is a very nice 6mm Radian on the classified site by BigMakStuov, I would buy it if in the UK. The 6mm Radian is a very good planetary eyepiece and grossly under-rated by many. I have owned the 6mm and know how good it is.

Alan

Would it be too cheeky of me to ask why you got rid of it, did you find anything better?

[John]

My planetary eyepieces from Tele Vue include the Ethos in 8mm and 6mm and 4mm and 3mm Radians. The Delos are gaining a super reputation too. I've also used the Nagler T5's for planetary and the Nagler 3-6mm zoom and they are hardly shabby either.

If I was in your shoes and buying from scratch I'd probably go for the 6mm Delos but the Radian would be very close and could work our considerably less expensive. The 6mm Ethos is excellent but very expensive compared to the others.

Having a wide field of view with an undriven dob does help tracking an object at high power I find although narrower field eyepieces can be used with just a little more care and attention.

If you come across a Pentax XW they are superb as well - possibly a wee bit better than the Radians and right up there with the Delos I reckon.

[Reeny]

I was using a 6mm Delos last night on Jupiter and Mars, in a 200P dob.

Conditions weren't great, so 200x magnification was a real struggle.

The moon was amazing. But the planets were shrouded by thin layers of cloud, and only worked with a modest 150x-165x mag.

I can definitely recommend the 6mm for planets.

Jupiter is better suited to 170x magnification - but I always try 200x and 240x just to make sure.

My 240x combination only works well on the clear nights /  50% of the time - so don't bust a gut spending big money on a 5mm just yet.

You need a 6mm for sure. You can start with that one first.

Then maybe a 7mm Pentax, or 8mm Delos for those claggy nights when the dampness and dew is hanging in the air.

A 7 / 6 / 5mm comination will give you a 20% increase on each eyepiece magnification.

A Delos combination of 8 / 6 / 4.5mm will give you 33% increase in magnification (if your wallet can take the strain)

[AlexB67]

Depending on budget and if you are thinking of buying in the pentax range, like the Radians the older pentax XLs are sometimes sold at a little more than the Radians. I almost thought I overpaid for mine but with hindsight the more I have used it I am so glad with that purchase.  I've seen them go a few times at around 150 a few times now whereas I got mine for somewhere around 110 I recall. While I've not looked through a 7mm XW I feel confident enough in saying that the  7mm XL would be almost nearly as good, 5 more degrees of FOV than a Radian, but 5 les than an XW.

I would say it is a similar comparison to deciding if you where thinking of buying a Delos versus a Radian. I do have the Radian 6mm and love it, a 7mm XW is on my to buy list, but if an 7mm XL turned up next month for significantly less than an XW (which new is around £ 255) I'd have no hesitation snapping one up for a lot less than a new XW.

Either way both will be excellent. 

Personally, in the short focal length ranges for planetary work that you are are looking for,  I would not be a 100% set on it having to be a TV to think you are going to get the bets views through a TV. The pentaxes are right up there AFAIK. 

If you are looking second hand if a good bargain turns up, be it Delos, Radians, Pentax XWs or XLs. The pentax like the Radian and Delos range all have that comfy 20mm eye relief anyway, and many wil argue that for the XW range at least they are about as friendly as they come for easy eye placement, if not slightly easier to get on with compared to the Radians/Delos range. That said personally I don't have issue with either the Radian or the XL in that way, though I've heard others reporting the Radians being a bit picky in that regard and needing to use the pupil guard. I do not find this at all, as long as you get the instadjust feature set to your liking.

[jetstream]

The Delos 6mm and 8mm are great,but I would not overlook the Pentax XW.There is a nice selection in the classifieds right now.

[Mike73]

I'm a Delos man through and through but both the 7mm and 10mm XW's are probably the finest EP's I've looked through.

[andyman]

No mention of the good old plossl...thats surprising...been around donkeys years and for good reason.will give as good a views as eyepieces mentioned above... at a fraction of the cost.

[michael.h.f.wilkinson]

No mention of the good old plossl...thats surprising...been around donkeys years and for good reason.will give as good a views as eyepieces mentioned above... at a fraction of the cost.

But they have rotten eye relief at 8 or 6mm. I have both Delos and XW EPs and love both. Superb on planets. As conditions allow, I use the 10mm XW, 8mm Delos or 7mm XW in my F/10 scope (corresponding to 6mm, 4.8mm and 4.2mm in your F/6 scope). Only under really poor conditions do I opt for the Nagler 12T4 (good eye relief too). I used to have Radians, and they are great as well. I must say, first the XWs (and XF) and later the Delos are just a touch better, and even more comfortable.

[rwilkey]

No mention of the good old plossl...thats surprising...been around donkeys years and for good reason.will give as good a views as eyepieces mentioned above... at a fraction of the cost.

Hi Andy, but not with the good eye-relief the OP stipulates unfortunately at the higher mags.

[AlexB67]

I guess the only way to go the plossl route and have some eye relief would be to buy perhaps a 15mm and barlow  to push out the eye relief distance a bit more, still that would be quite costly for a decent barlow, and you'd still only have the 50 degree FOV, just about as many elements in the train as a good dedicated eyepiece and could end up paying a fair bit overall.  A TV 15mm plossls plus decent barlow, you are getting into high prices. Not a route I'd opt for to just get the eye relief unless you already happened to own a good barlow and use it as a sort of stopgap solution if you had nothing else.

If I go for the tigthies I accept they are tight, like the 5mm BGO I have and enjoy/accept them as they are, minimal glass, great light throughput/contrast, but in a peephole and very narrow FOV.

[bingevader]

The plossls are the only TV EPs I'm likely to own.  I'd have to say, I've been surprised at how comfortable the ER is on the 8mm. I wouldn't have considered it previously, but nothing much else was appearing on the second hand market at 8mm. It was very reasonably priced on here, so I thought I'd give it a go. Its quite a nice FL in an 8", 1200mm 'scope, so I wouldn't rule it out altogether.

[alan potts]

Why did I get rid of the 6mm Radian. It was because I bought the 6mm Delos and then a 6mm BGO and then a 6mm Ethos and after smashing the first, another Delos, one just can't have too many eyepieces around this focal length. Selling it was a mistake.

To me it is not really a case of anything else being better there is so little difference in the quality of Televue products with regard to sharpness. FOV varies of course but different targets and scopes get different eyepieces used in them. Meaning that I normally use the Ethos only with short scopes and the Delos and Radian if I had one more for higher powers in other scopes.

Alan.

[allen g]

I have the 6 and 8 delos and both are superb.  72* with 20mm ER (and adjustable). The have the quality of the ethos.  I also have the TV 2x barlow which does a great job when more mag is desired. 

[Daz Type-R]

Guys thank you very much for all your replies, certainly has given me something to think about.

My other option would be to get a TeleVue 2x PowerMate, that and my 13mm Ethos would give me a 6.5mm ep reducing the AFOV down to 50 degrees (not a problem when using for planetary viewing) and should give me a magnification of 185x, which I will probably use more than those rarer clear nights when 200x mag plus will be possible while still keeping the eye relief.

Hmmmm, going to go for a think over this one.

Thanks once again.

[John]

I have a 2" 2x Powermate which I use with my 8mm and 6mm Ethos. Basically you get 4mm and 3mm Ethos still with the 100 degree field of view. It's a heavy combination but works extremely well.

[Daz Type-R]

I have a 2" 2x Powermate which I use with my 8mm and 6mm Ethos. Basically you get 4mm and 3mm Ethos still with the 100 degree field of view. It's a heavy combination but works extremely well.

It keeps the FOV when power mated????

I thought it would of reduced it?

Hay hoo, live and learn, thanks.

[michael.h.f.wilkinson]

The apparent FOV does not change (with a powermate or other telecentric barlow, with an ordinary barlow it might), but the true FOV is half the size.

[Pig]

He did say f/6 reflector, sig says 200P, combined that suggests the 1200mm variety. :cool:

That's why I asked  because I wanted to be sure.

[John]

It keeps the FOV when power mated????

I thought it would of reduced it?

Hay hoo, live and learn, thanks.

Yep - as Micheal says, the apparent field of view stays the same but the true field of view reduces because the magnification has increased.