Televue 12mm T4 Nagler, Televue 13mm T6 Nagler and 13mm Ethos

[alan potts]

Russell,

Sadly I did n't do a test on reading glasses as with both having ER of 20mm I just didn't think anyone would have a problem with that. I really don't think glasses is an issue with either as I know Michael over in Holland uses the T4's due to fact he has to wear them.

Sorry for the slight side step in subject Derek.,

Alan

[Moonshane]

great write up Derek

If you are at PSP in October, I have a 12mm T2 and will be interested to compare this with either a 12mm T4 or 13mm Ethos to see if  made the right decision or if I need to start saving again LOL.

[Moonshane]

ps I have never seen moons on either Neptune or Uranus. Must try harder!

[John]

ps I have never seen moons on either Neptune or Uranus. Must try harder!

Me neither - it's good to have a challenge though

It was interesting that the Ethos helps a little with this though. It was a similar ability in the Pentax XW's over Naglers on Saturnian moons that impressed me enough to migrate from Naglers to Ethos / Pentax XW as my mainstay eyepieces. They seem to produce a slightly tighter image with less surrounding scattered light which helps spot these faint objects adjacent to the much brighter one. 

Small and subtle differences such as this and perhaps ergonomics are about all that sets these eyepieces apart when you get to these premium levels of overall performance.

[DRT]

great write up Derek

If you are at PSP in October, I have a 12mm T2 and will be interested to compare this with either a 12mm T4 or 13mm Ethos to see if  made the right decision or if I need to start saving again LOL.

Unfortunately not, Shane. On the up side I will be in Grenada looking at a lovely dark sky with my new C6 SCT and my plossls

If I hang onto them all for a while you can have a look at SGL10

[Moonshane]

how awful for you LOL

[astronymonkey]

Hi derek,

Its great to see this review and how you have found these eyepieces.

I wonder though how this would turn out when using a faster scope like your dob, in this case I wonder if the additional field of the ethos would give pristine views to the edge or if any fall off in sharpness would taint the experience.

Another challenger to add to this could possibly be the 12mm delos eyepiece. I have the 6mm and 8mm and find these are extraordinarily competent eyepieces which I find even better than the nag T4 range. Often when going up to higher powers the image decreases in quality but I find moving up through the naglers and onto the delos improves the view.... maybe this is because im straining to see small features when at low powers and the high power helps with this, but either way the delos are absolute stunners and im sure would only lose out to ethos on fov but would balance this out with much better eye relief.

Cheers

Ian

[DRT]

Thanks, Ian.

I do plan to try them in the Dob but confess I am still a novice when it comes to operating the manual GOTO and Nuge-tracking features  

I have ordered a second Telrad (which my wife tells me arrived today) so once that is fitted I might actually be able to find something useful to do an EP review on. I will report back here when that happens.

I've not yet looked through a Delos, so that will have to go on my bucket list,

[John]

I agree that the dob will stretch these eyepieces capabilities more than the SCT did and should highlight their differences more. I can't see a coma corrector in your kit list so you will need to be aware that edge of field issues are likely to comprise of coma from the scope rather than deficiencies in the eyepieces - one of the things that Tele Vue are very good at is producing eyepieces that are sharp to the edge in fast scopes. They can't correct coma though.

[DRT]

So would you go for a generic coma corrector or a TV Paracor, John?

I haven't had the Dob out much since I bought it so have yet to experience the phenomenon of Coma but have read a few bits of advice similar to what you have posted here so guess I will have to buy something.

[John]

I don't use one myself as my dob is F/5.3 and coma is not really a significant issue with that. I'm not saying you definitely need one either as many folks don't use one with 12" F/4.9 newts but I think you are likely to see some coma at the edges of the FoV of the Tele Vue eyepieces, especially the Ethos.