3 quality eyepieces. Suggestions please..

[boyfromlincs]

hi, i want or need three quality eyepieces for my 8 inch skywatcher dob, i wear glasses all the time and my main interest is the moon and planets, im thinking about the tele vue 27mm panoptic, and the tele vue delos in 6 mm and 12 mm, i was thinking about the tele vue nagler type 6 but i dont think the eye relief is enough for me.. any other suggestions are very welcome as i want to get it right before i spend as i only want to do it once.. thanks..keith..

[Andrew*]

Hi Keith,

Since you wear glasses, I would suggest that Type 6 Naglers would not be suitable for you, but the Type 4 may appeal as they have long eye relief.

You can not go wrong with the Delos range. They are all the rage at the moment, with many owners claiming they are the best eyepieces on the market at the moment. They are often compared to the Pentax XW range, which would be an equally safe bet.

The Panoptic 27mm with its 19mm eye relief would also be a very good performer. Depending on how old you are and how dark your skies, you may even get away with a 35mm for low power. If you want to save a little money without compromising the quality of the views, a 30mm Skywatcher Aero would be very competent in your scope and they are half the price of a Panoptic.

You may find just having 27, 12 and 6mm you are a bit restricted as your highest power is on the low side, and in the 8", something between 100-150x (7.5-10mm) is ideal for smaller deep sky objects such as globular clusters and planetary nebulae, so consider adding a 8mm Delos or adding a barlow to the collection with a 14mm or 17.3mm Delos). You'll be easily able to use a 5mm in an 8" dob, so one solution would be a 14mm and 10mm (available in both Pentax or Delos ranges) and a good quality 2x barlow to give 7mm and 5mm.

[boyfromlincs]

thanks for the info, im 53 years old if that helps and i live in a village and the skies are very dark with no street lights in view..

[John]

I'm 53 too but do have a few streetlights to contend with

You can't go wrong with the Delos range as far as I can see. I might be tempted to go for a 22mm T4 Nagler in place of the 27mm Panoptic though. I used to use one in a 200P dob and it was really nice !

[Stu]

You will be easily able to use a 5mm in an 8" dob, so one solution would be a 14mm and 10mm (available in both Pentax or Delos ranges) and a good quality 2x barlow to give 7mm and 5mm.

I think, given your needs, this is a great suggestion, perhaps with a Powermate rather than Barlow if budget permits.

This would give you x85, x120, x171 and x240 which for three eps covers much of what you would require.

Stu

[boyfromlincs]

now i understand about a barlows, whats a powermate is it a higher quality barlows ???

[Luke]

+1 for Delos. I don't wear glasses, but find long eye relief eyepieces comfy. I found the 8mm Delos to be better on Jupiter than an 8mm Radian, and the Radian is no slouch on planets. The Delos barlows really well, so I don't know if you'd want to consider covering a wider range using a barlow?

[Stu]

I'm sure someone will give a better explanation, but my understanding is that it amplifies the image but the light rays emerge from it parallel rather than converging as in a Barlow. The result is that the multiplying factor doesn't change with the distance of the eps from the PM, and the eye relief of the eyepiece is maintained, whereas a Barlow increases it which can be inconvenient.

An often used phrase is that the PowerMate just 'gets out if the way', adding image scale but not degrading the image at all. I would certainly describe it like this.

Stu

[boyfromlincs]

definatly want the delos now, just got to get the sizes right

[boyfromlincs]

thanks for that, a powermate seems the way to go............when funds allow..

[Stu]

A couple of things to consider. Maybe avoid eps which are direct x2 multiples of each other as you can use a Barlow/PM to achieve the same result.

I would say that for the sorts of targets you describe, magnifications from the x80 up to x200 plus would be useful

Jupiter is often best at around x150 to x180, Saturn seems to take more, maybe x160 to x200 and Mars tends to require more still, up to x250 ish on good nights. The moon will often take whatever you throw at it as the contrast is so high x200 and upwards can work well, although it is nice to be able to take in the whole disk with space around too at times.

The 27mm Panoptic would be a lovely lower power, but not necessarily so useful on the specific smaller targets you describe.

There are no hard and fast rules, just throwing a few thoughts out there for you to consider.

Stu

[boyfromlincs]

thats the problem stu, making up my mind before i buy as its a lot of cash to lay out and im not very knowledgeable on the ins and outs of eyepieces, just want to make sure i get the best i can for the dob...

[Stu]

So.....

How about buying a number of cheaper, second hand eyepieces in various focal lengths until you get the hang of what you like before committing to the more expensive ones?

One problem, if it is a problem, is that jumping straight to the best doesn't let you learn what the less good are like so you may not appreciate the improvements.

Anyway, experimenting with cheaper eps might be the way to go, and could save you wasting cash by having to sell and buy the TV's again if you find you don't like the focal lengths you've chosen.

Stu

[boyfromlincs]

had my dob about 8 months now and been using various eyepieces from differant companies and mates eyepieces in various sizes, thats whats helped me make my mind up tp buy some better ones, dont want to go down same road as some mates who have a dozen or more eyepieces they never use..

[boyfromlincs]

should have daid been trying out some ep's at local astro club aswell..

[Andrew*]

What eyepieces do you already have, Keith?

Tell us what you feel about them. Which do you pick up most often?

[boyfromlincs]

now thats a very good question, i have a revelation 30mm 2 inch, nice but lacks sharpness, a skywatcher 16mm extraflat which always seems to want to fall to bits on me, a skywatcher 6mm extrawide fov, i borrowed a 12mm tele vue off a mate and found that was the most used along with the 6mm, i like the 30mm range for general searching before i go smaller..

[Stu]

Are you fixed on three eps, and do you have a budget limitation?

Stu

[boyfromlincs]

three seems to do me for what i want, as for budget i can always go begging to the misses.. or boss as i call her..

[Andrew*]

Okay, that's very useful. I think you need to upgrade your 30mm. The Panoptic 27mm would be a good upgrade, but if you like the 82° feeling, the 22mm Type 4 Nagler offers 95% the true field of view but with more contrast and magnification. Personally, however, I use my low power eyepiece as a finder, so I prefer to have a lower power, 70° FOV which is easier to spot things in. Since you say you like the 30mm range, do consider the Aero. My 40mm impresses me every time and the eye relief is fantastic.

You may find the gap between the low power and your 12mm very large, so think about a 17.3mm Delos (you will get it for £250 at the moment if you ask) to replace your 16mm ExtraFlat, and a 12mm Delos. With a 2.5x Powermate, this will yield 6.9mm and 4.8mm. You will have 33x, 58x, 83x, 145x and 208x. I think that's a pretty good range. A 10mm instead of the 12mm may balance the range a little more, or you could always add it at a later date.

Andrew

[boyfromlincs]

is it true that with a powermate you lose no image quality ??

[Stu]

In theory a dedicated ep should beat a PowerMated one, but in practice there is little or no noticeable difference.

It can get a little cumbersome if using the PM with some of the bigger eps and may make balancing the fob more challenging.

Stu

[boyfromlincs]

May aswell save the extra for another eyepiece then or i will try one first as somebody at the club should have one with a bit of luck..

[Pig]

Hiya Keith,

On Friday night I used by 12mm Delos with 2 X Barlow (thus 6mm) The view was brilliant and as a result I am going to purchase the 8mm tonight and 6mm Delos later this month.

Please consider how fine your focuser's adjustment is, you may need a dual or very fine focus capability when viewing at high magnifications especially on the moon and planets

(6mm in my scope is X391 magnification)

There is nothing more frustrating than if you cannot hit that sweet spot when focusing

[Andrew*]

May aswell save the extra for another eyepiece then or i will try one first as somebody at the club should have one with a bit of luck..

Do give barlows a chance. With relatively light eyepieces as the Delos, they are not too cumbersome and they really do have the power to double your collection!

Some people don't actually like using them. I never used to use them, preferring native focal lengths, but at the moment I am re-structuring my collection around two good quality barlows. For me, I didn't like the extra time it took to fit them between the eyepiece and focuser, but it really only takes seconds, so I have decided to ignore this inconvenience for the sake of family finances!

Ordinary barlows can also increase eye relief, which can be a good or a bad thing depending how much eye relief there already is, and can cause vignetting. This is not the case with my 10mm Delos, which barlows extremely well, but the 17.3mm may be different. Buying a Powermate will be very safe in this respect as it does not converge the light rays.

Loss of light or sharpness is negligible and not observable in most circumstances. High quality barlows will have better light transmission and will not degrade the contrast.

Andrew