Perfect Set

[globular]

Hi all.
I'm after some opinions and advice regarding building up my eyepiece set (pretty much from scratch).

I have an 8" Edge HD SCT F/10.5 which I use for visual only.  I like to do a bit of everything; planets, nebulae, galaxies, clusters.
I don't wear glasses but share my scope with my wife who does.  [edit: apparently she shares her scope with me 🤐]

I've put together the following list of EPs that I'm thinking about:

I tried to select fl gaps that will fill nicely with a 2x powermate (no overlapping) but where the EPs used on their own will be at the most useful spots.
I've selected ones with eye relief between 19 and 22; and with wide fov but not super wide; so that both with and without glasses should work well.
I know ES 92 in a Powermate is a weighty combination but I think my mount will manage it ok.
I have a Hyperflex 7.2-21.5 Zoom for when narrow FOV isn't an issue, but feel some individual EPs with wider FOV are needed too.

Have I overlooked any EPs that would work well / better?
Any on the list that have an alternative that might be better?  Similar at lower cost? Or better and worth the extra?
Is this too many?  Or not enough? 
The Morpheus and Delos ranges are tempting too - but their fl didn't seem to slot into the list as well.  Maybe I'm being over mathematical?

Look forward to your advice.

Edited September 19, 2020 by globular
matrimonial bliss, hehe

[Louis D]

You do realize that exit pupils below about 0.5 are rarely usable?  As such, I would forget about the Powermate.  I would put that money toward a 72mm ED refractor and mount so you can observe wide fields that your 8" SCT can't come even close to revealing.

The 10mm and 12mm are fairly close.  I would probably substitute the 9mm Morpheus for 226x.  Mine seems to work about as well as my 10mm Delos.

I don't see much if any reason to go above 306x with your scope, so the 7mm Pentax XW should be fine for nights of exceptional seeing.

I have the 30mm APM UFF and both ES-92s.  You'll really like them.  The 40mm Pentax XW should be very good as well, although I have no personal experience with one.  I use a 40mm Meade 5000 SWA (Maxvision) at that focal length.

For the ES-92s, I'd check to see if you'll need to add some sort of counter balance to avoid overworking the mount.

[globular]

Thanks for the advice @Louis D

Yeah I know pupils below 0.5 are rarely usable and agree 300x mag is the place to stop.  The Powermate was there to give the 20, 15, 8.5 and 6mm (all >0.5mm pupil).  The resulting 5 and 3.5 are just 'free' bonuses for exceptional seeing.

If I drop the Powermate would the gap from the 30 to the 17 be too big?  I'd probably then want something like the 22 Nagler.  But then this is likely too close to the 17 to have both (not to mention cost).  I like the idea of the ES 92 series as it's the only one I am aware of that gives that level of FOV with eye relief comfortable with glasses.

It's a similar story with the 12mm and 10mm being close.  I feel I "want" the ES 92 12 for the FOV but then without the 10 I'm not covering the mags from 178 to 306, which feels too long without any coverage.  This brings a 9 or 10 back into the equation, or a Powermate.

If I drop the Powermate and pretend the ES 92 series doesn't exist then I'd probably end up with:

Not sure I can get behind that as much as the original list though. I can't convince myself the Powermate is a bad idea (I feels like you get "free" EPs) and I can't help wanting to try super wide FOV.
Then again it's growing on me.....🤔

Thanks again Louis. Suggestions like this is exactly what I was hoping for to challenge my logic and fill my knowledge and experience gaps.

Edited September 20, 2020 by globular

[Louis D]

I have the 22mm Nagler T4 as well.  It's very nice, but a bit tight on eye relief compared to the others you have listed.  If you can pick up one used for about $300 equivalent, it's a good deal.

You'll find you'll either leave the Powermate in or out, but not continuously swapping it.  Thus, it's not really that useful for filling gaps.

The 17.5mm Morpheus is another option if you want to stay light and less expensive.  I've thought about picking up one for this reason.

I still recommend budgeting for a 72ED on an alt-az mount for 11x to 62x powers.  I really enjoy cruising star fields and observing clusters and asterisms that are too big for long focal length scopes.

[globular]

2 hours ago, Louis D said:

I have the 22mm Nagler T4 as well.  ...  If you can pick up one used for about $300 equivalent, it's a good deal.

How about I give you $325 for yours? 🤣

72ED is food for thought.  I've had plenty of times I wished I had more sky at my eye - but there is so much more to enjoy I'm in no rush to go multi-scope..... yet.  Would a plan to add this at a future date change my EP choices now?  It seems to me that the ones I'm considering would work well in the 72ED too? Except weight perhaps?

Edited September 20, 2020 by globular

[Louis D]

1 hour ago, globular said:

How about I give you $325 for yours? 🤣

72ED is food for thought.  I've had plenty of times I wished I had more sky at my eye - but there is so much more to enjoy I'm in no rush to go multi-scope..... yet.  Would a plan to add this at a future date change my EP choices now?  It seems to me that the ones I'm considering would work well in the 72ED too? Except weight perhaps?

Yeah, I don't think so on the 22mm NT4. 🤨 It took me years to find one for $260 shipped.  I had been using the 22mm AstroTech AF70 quite happily for years before that.

I was thinking the wife would like to have a scope to look through while you're locating targets in the Edge HD.

Heavy eyepieces do tend to want to make a 72ED turn turtle.  You have to rig up a counterweight at 90 degrees to the scope to counteract the heavy eyepiece at higher altitudes.

Otherwise, the eyepieces work well in the 72ED.  You will notice field curvature due to the short focal length.  I ended up adding a TSFLAT2 field flattener to the front of the 2" diagonal to flatten it out.  The other issue is you have to have an altitude lock on the mount to keep the scope on target during heavy eyepiece swaps.