Eyepiece choice help/advice needed

[Jamie]

Hi folks

I have just had a 12" flextube delivered a week or so ago and i am looking for a "good" quality eyepiece to compliment the scope.

I already have a Meade series 5000 40mm to get me going and a selection of plossls.

Your suggestions please?

Could you please explain your suggestions (as in your reason for this choice)

Thanks.

[Ben Ritchie]

What's your budget? and any particular interests, or are you looking for something to cover all bases?

[Jamie]

My budget is not an issue on this one.

I would like something to cover more or less all bases..... (if that's possible)

[Ben Ritchie]

Ok, without worrying too much about money i'd suggest a 17mm T4 or 20mm T5 Nagler, plus a 1.6x 2" Barlow. Not a cheap option, but will give fantastic - and well-corrected at f/5 - medium power views, plus barlow nicely for higher power. Or worrying even less about money i'd go for the 13mm Ethos, which should be superb in that 'scope. The wide AFOV is good for two reasons; the proverbial 'spacewalk' effect, and with an undriven mount it makes finding a target and keeping it in the field of view significantly easier.

Both the 17T4 and 20T5 are great, but the type-4s have significantly more eye relief. The 20T5 is sharper though, probably my favourite of all the Naglers.

... as it happens i'm thinking of buying the very same 'scope myself, so interested in your reports of it!

[russ]

Money no object..wow! It would have to be the 13mm Ethos. That would be such an amazing view. But as Ben says the Nagler is a superb option. I can only speak for the 16mm T5, which is perfect for me but if the 17mm T4 is better, then that's one incredible eyepiece.

Jamie, not sure what filters you have but i highly recommend getting a narrowband filter to go with the 12. I was out last night with the Orion UltraBlock. My first go with it and the 12.5. Under semi-dark skies and a nearly full moon i could just see M27 without the filter. Then slotted in the UltraBlock.....almost fell over backwards!!!! It was like the view i had from a dark site....awesome. M57 was equally impressive.

Regards

Russ

[MartinB]

Jamie, I have a 300mm skyliner. I have a 30mm UWA moonfish which isn't ideal for an F5 scope but the image scale is useful. Something in the 30-40mm range is definitely going to see some use. A 40mm TMB paragon would definitely be worth considering. In fact I might get one myself. I also have a 27mm Panoptic which gives lovely views.

I agree with Ben that the 17mm T4 Nagler is very good. Probably my most used EP in the scope is a Pentax 10mm XW. With this aperture you can move to higher powers gaining lots of contrast but without the view becoming too dim. The Pentax works really well in this respect. It is also my favourite for lunar sketching.

The higher power EPs need to be widefield for the Dob for obvious reasons.

I discovered last night that the lower power wide field EP views are transformed by a coma corrector. You could consider the Paracor but I've recently bought the Baader multipurpose coma corrector which works fantastically well. I hope to write a report on this over the week-end. My advice now would be that this is a very important accessory for expensive wide FOV low power EPs.

My EP collection isn't based on any logical rules regarding the ideal choice of focal length mix, just haphazard second hand purchasing!

Agree with Rus about the value of LP and emission line filters. I use a UHC and a CLS. The UHC would have been particularly good last night With the 12" aperture you can use the CLS on galaxies with good improvements in contrast whilst still retaining faint detail

[russ]

Martin, I had the Baader MPCC last year with the Orion Optics 12" f4 and the Pentax 14mm XL. It all made a wonderful combination and that MPCC really does do what it says on the tin. I just need to wait for a nicely priced secondhand one.

I just use the Baader Neodymium to help out on galaxies. Just darkens the background sky a tad and helps the galaxy stand out. CLS sounds good though.

[Ben Ritchie]

I agree with Ben that the 17mm T4 Nagler is very good. Probably my most used EP in the scope is a Pentax 10mm XW.

The 10XW is a lovely eyepiece, but the reason i'd suggest the 17 or 20mm Nagler is that with a reasonable 2" barlow you can get 95%+ of the performance of the XW and have a lower-power eyepiece too. I spent some time swapping between the 17T4 + 1.7x AP BARCON and a 10mm XW, and couldn't see a whole lot of difference.

[FLO]

Probably my most used EP in the scope is a Pentax 10mm XW. With this aperture you can move to higher powers gaining lots of contrast but without the view becoming too dim. The Pentax works really well in this respect. It is also my favourite for lunar sketching.

Jamie, you are welcome to borrow mine for Keilder

[MartinB]

I've got the Pentax 10mm and the Nagler 17mm, not because of any careful systematic purchasing plan, just that they cropped up on astro buy n sell, doesn't make sense really!

The moonfish 2" ED x2 barlow is also pretty good

[Ben Ritchie]

I've got the Pentax 10mm and the Nagler 17mm, not because of any careful systematic purchasing plan, just that they cropped up on astro buy n sell, doesn't make sense really!

pre-Ethos the 10XW and 17T4 were the core of my favourite eyepiece lineup ever - 5, 7 and 10XWs, 17T4 and 31T5. Great pair IMHO.

[John]

I've got the Pentax 10mm and the Nagler 17mm, not because of any careful systematic purchasing plan, just that they cropped up on astro buy n sell, doesn't make sense really!

I'm glad I'm not the only one that uses that "strategy" sometimes

John

[Astronut]

If money's no object, then the 13mm Ethos is the way to go - the reviews don't lie. Simple reason - the extra wide 100 degrees AFOV.

Couple that with a Powermate for higher magnification and you've still got that wide field and no effect on eye relief.

The Pentax XW's are excellent too with a generous 70 degree AFOV.

I got the 30mm XW for low power. I chose 30mm because the exit pupil is the optimal size (approx 6mm) from my 12" f/5. A 40mm eyepiece would give an exit pupil of 8mm which may have been a bit too wide for my eyes.

[ollypenrice]

Hey, great to see all those TeleVue nuts out there. I'm another! I really don't think you can beat them and the Ethos (I don't have one but have used a couple) are to die for. But the 19mm Panoptic is divine. What kind of power do you want?

Anyway, you're only here once so go for TeleVue. (I have a 20 inch Dob with a remarkablly good Beacon Hill mirror but be fair, it is F4.1 and did not cost the earth. The TeleVues clean up the edge of field in a way that the others just don't.)

Olly.

PS Don't we all love spending other people's money??

[Andrew*]

Hi Jamie,

I would start off with a TeleVue Paracorr to tackle the coma.

As for eyepieces, I think you couldn't go wrong with (yes, you guessed it) an Ethos. Steep, but hugely versatile and generally mind-blowing according to every report I've heard. The 13mm might be a little high powered for general use (117x), but would almost give a degree field. Better would be the upcoming 17mm Ethos. Not cheap at about £500, but it would get lots of use. Make the most of it and buy a decent 2x or 1.6x barlow.

Andrew

[Astronut]

....Better would be the upcoming 17mm Ethos....

A 17mm Ethos on the way :shock:

oh 'eck, there's still some room in my eyepiece case