Help me to make/start an EP set

[scibuff]

Hi guys,

tomorrow I'm getting either the NexStar 6SE or 8SE (depending of what I like in the shop) and I'd like some advice as to what set of eyepieces I should get with it.

Primarily, I'll be taking the telescope to some public observations my friends and I are organizing every other weekend (otherwise I'd personally go for the CPC800 but I take it that one is way too heavy to carry around all the time, am I wrong about that?). There, we usually wanna show people who stop by some planets, binary stars and some of the brightest DSOs (M31, M42, M45, etc).

Here is what I'm thinking to get for EPs

- 7mm X-CEL (60deg)

- 11mm Explore Scientific (82deg)

- 18mm X-CEL (60deg)

- 25mm Plossl (comes with the Nexstar) (50deg)

which should give me the following magnifications / FOVs

6SE: 214x / 17', 136x / 36', 83x / 43' and 60x / 50'

8SE: 290x / 12', 184x / 27', 113x / 32' and 81x / 37'

In case of 6SE I think I'm pretty much set for virtually anything we may need, 7mm for planets, 11mm ES for DSO's, etc

If I go with the 8SE, the 7mm EP resulting in 290x is probably going to be too much most of the year, so a 2x barlow to use with the 18mm for 225x / 16' seems like a good idea?!

I'd appreciate any feedback you may have for me. Please let me know if I missed anything e.g. should I just get the 2x barlow regardless (it would give me extra 120x, 166x and 272x with the 6SE, ignoring the 428x option probably), or should I get a 3-5mm, 9mm, 21mm, 30+mm?

Thank you

[ollypenrice]

I'd rather have three excellent EPs than ten very good ones. My opening gambit!  But I mean it.

Olly

[michael.h.f.wilkinson]

I have a 7mm Pentax XW for my C8 (same optics as 8SE) and it does get used, but only on nights of good seeing. A 9-10mm is best for planets in these scopes on most nights. I would personally have a good look at the MaxVision 68 deg EPs: excellent value for money. Replace the 25mm Plossl by the 24mm MV. Add a 9 or 10mm long eye relief planetary EP (doesn't need large FOV), like the Vixen NLV/SLV line and you have moderate wide field and planetary covered.

For larger FOV viewing you will need a 2" visual back (and 2" diagonal) in the 8" scope like my former 40mm 68 deg TMB Paragon (now sold as the SW Aero), or again the MaxVision 40mm 68deg. Those EPs will see LOADS of use for wider field viewing. For M31, M45 and some other big guys that is the way to go (and even then it can be a tight fit). That would require three EPs : 40mm for very wide, 24 intermediate, 10 or 9mm for planetary.

You can always add intermediate EPs like a 16-18mm, or a shorter one at 7-8mm for good nights on planets later

[scibuff]

I have a 7mm Pentax XW for my C8 (same optics as 8SE) and it does get used, but only on nights of good seeing. A 9-10mm is best for planets in these scopes on most nights. I would personally have a good look at the MaxVision 68 deg EPs: excellent value for money. Replace the 25mm Plossl by the 24mm MV. Add a 9 or 10mm long eye relief planetary EP (doesn't need large FOV), like the Vixen NLV/SLV line and you have moderate wide field and planetary covered.

For larger FOV viewing you will need a 2" visual back (and 2" diagonal) in the 8" scope like my former 40mm 68 deg TMB Paragon (now sold as the SW Aero), or again the MaxVision 40mm 68deg. Those EPs will see LOADS of use for wider field viewing. For M31, M45 and some other big guys that is the way to go (and even then it can be a tight fit). That would require three EPs : 40mm for very wide, 24 intermediate, 10 or 9mm for planetary.

You can always add intermediate EPs like a 16-18mm, or a shorter one at 7-8mm for good nights on planets later

Thank you for that feedback Michael. Two questions:

1) won't 2" diagonal + 2" EPs add quite a bit of weight to already somewhat "fragile" single fork mount?

2) I'm reading the 6SE has a 1.25" baffle tube so 2" diagonal won't really help?

I'll need to look into CZ/SK/AT stores which sell MV EPs as I'm not aware of any off the top of my head but I'm sure there will be at least one or two.

Thank you

[Digger1895]

Just a quick question to add to yours, aren't nearly all EPs from a range par focal with each other?

[YKSE]

Thank you for that feedback Michael. Two questions:

1) won't 2" diagonal + 2" EPs add quite a bit of weight to already somewhat "fragile" single fork mount?

2) I'm reading the 6SE has a 1.25" baffle tube so 2" diagonal won't really help?

I'll need to look into CZ/SK/AT stores which sell MV EPs as I'm not aware of any off the top of my head but I'm sure there will be at least one or two.

Thank you

What I see it is

1. Yes, the 2" diagonal + 2" EPs will add some unwanted weight, especially the EPs.

2. The baffle tube of 8SE is 37mm, and 6SE is 27mm, I'm using SW aero 40mm(46mm field stop) in C8, no visible vignetting to my eye,  and many others confirmed it too, the reason is that the buffle tube doesn't lie in the focus plane like field stop, also our eyes are not very sencitive to gradually dimming towards the edge (most reflectors don't have 100% illumination in the edge e.g.).

For C6, using a focal reducer may be the best solution for getting the widest field of view in low mag.

As to the question about parfocal of same range EPs, this is more saleman's argument than in reality, more than often, you need to tweek the focuser switching those parfocal EPs.

[Qualia]

Hi guys,

tomorrow I'm getting either the NexStar 6SE or 8SE (depending of what I like in the shop) and I'd like some advice as to what set of eyepieces I should get with it.

If possible go for the bigger the aperture.

Also, give yourself some observing time to understand what kind of thing the scope excels at and also its shortcomings. In a few weeks you'll appreciate just a little more some of the gear you may be missing and will then be able to make a more informed purchase. Astro gear is quite pricey, so don't rush into buying new eyepieces until you've checked out your new scope.

[fondofchips]

As a fellow newbie go for the bigger scope & take your time sorting out your eyepieces, patience is the best asset in astronomy.

[michael.h.f.wilkinson]

Taking your time makes sense. I tend to replace kit only when I feel I am limited by its performance. I had my initial three-Plossl + focal reducer set-up for quite a few years before replacing the 10mm with somthing with more eye relief (the Vixen LV 9mm). I added an LV 7mm later for just a bit more magnification on planets (for when the seeing was good). Only about 4 years ago did I get myself the first premium EP (TMB Paragon 40mm). So for the first 15 years that I had the scope I used Plossls and LVs and was quite happy.