2 eyepieces plus barlow = all I need ?

[Stu]

2 hours ago, John said:

This begs the question Stu, what would your ideal set be ?

Well.....

I reckon I could survive  with:

31mm Nagler

21mm Ethos

12.5mm Docter

Leica Zoom/VIP Barlow and/or AP Barcon

[John]

Just now, Stu said:

Well.....

I reckon I could survive  with:

31mm Nagler

21mm Ethos

12.5mm Docter

Leica Zoom/VIP Barlow and/or AP Barcon

Hmmm - yes, thats a very interesting set

Personally I might add the 2-4 Nagler zoom in there as well for close binaries but otherwise I can see that set ticking all the boxes in a variety of scopes.

[Stu]

32 minutes ago, John said:

Hmmm - yes, thats a very interesting set

Personally I might add the 2-4 Nagler zoom in there as well for close binaries but otherwise I can see that set ticking all the boxes in a variety of scopes.

Could you barlow the 3 to 6mm to get a 1.5 to 3mm??

[John]

43 minutes ago, Stu said:

Could you barlow the 3 to 6mm to get a 1.5 to 3mm??

If I had a 3-6 zoom I could do that. I've just got the 2-4mm though

I've yet to try the VIP barlow with anything other than the Leica zoom. With the zoom I'm stuck at 1.65x or so because of the limitations of what I can fit into my diagonals without impacting the mirrors / prisms. I'll find a way round this soon though I'm sure.

The VIP barlow works very well indeed with the Leica ASPH, as reported by others. The only downside (apart from the stack length) is that I've noticed a little edge astigmatism creeping in at 1.5x and 1.65x amplification. I understand that this will decrease at 2x. It's not a big issue though - the view through the central 80% of the FoV is fantastically sharp and contrasty

 

[Richard Hather]

This post has really got me thinking could I manage on 3 eps Es 20-14-9 100s ?

[Stu]

2 hours ago, John said:

The only downside (apart from the stack length) is that I've noticed a little edge astigmatism creeping in at 1.5x and 1.65x amplification.

Yes, I think that is one of the known effects of the element being positioned closer to the eyepiece for less that x2 multiples, something I never really used other than when experimenting.

[Piero]

22 hours ago, John said:

The combination of sheer optical quality with the instantly variable focal length, a decent FoV (58 - 75 degrees) and viewing comfort are starting to win me over

 Zooms can be very powerful if optically good! I like mine so much that now it has a little brother!   

[bingevader]

10 hours ago, Alien_Photons said:

An astronomer with to many eyepieces has the same problem as someone with to many clothes. They spend so much time thinking about what to wear they end up missing half the party.

I have two and a power mate.

No, you don't have to turn up late for the party, you just turn up terribly over-dressed!  

[Louis D]

10 hours ago, Alien_Photons said:

An astronomer with to many eyepieces has the same problem as someone with to many clothes. They spend so much time thinking about what to wear they end up missing half the party.

I have two and a power mate.

Given the limited view angle from my backyard, it can take hours for new, interesting objects to appear.  As a result, I'm looking at the same thing for a very long time.  As a result, I find myself playing at the scope(s) with various optical combinations and seeing how they interact.  For instance, how does a long 2" barlow compare with a shorter 2" barlow coupled with a TV PBI when used with various 2" eyepieces.  It's interesting to note what works well together and what doesn't.  It's also interesting to compare binoviewing to monoviewing during the same session.  I've also done 1.25" barlow shootouts some nights.

It's not unlike sharpshooters who have multiple target pistols to choose from or musicians who have multiple versions of the same instrument to choose from.  They tend to collect things of interest to them over time and revisit them when the mood strikes.  Come to think of it, I'm not sure target shooting is as big in the UK as it is in the US (especially Texas), so y'all can ignore that example.

[John]

I think it's miuch easier to accumulate hobby stuff than it is to let it go, of at least it seems that way

[Charic]

On 20/07/2017 at 22:25, John said:

Just kicking around an idea of slimming my eyepieces right, right down to:

- Lunt HDC 20mm / 100 degree 2"

- Leica ASPH 17.9mm - 8.9mm used with 2" adapter

- Baader VIP barlow - used with above zoom to get FL's down to 3.5mm or even 3mm

Set those aside John, and box the rest! Give it a Month or so, and see how you feel with the basic set? 

Once their gone, their gone, I still feel my Delos sales may have been premature, but too late now, and no way will I get the same collection again at the prices I paid for them?  

[John]

13 minutes ago, Charic said:

Set those aside John, and box the rest! Give it a Month or so, and see how you feel with the basic set? 

Once their gone, their gone, I still feel my Delos sales may have been premature, but too late now, and no way will I get the same collection again at the prices I paid for them?  

Sound advice I'm sure

 

[jetstream]

The Leica Aspheric provides ortho performance with an excellent widefield view- a combination that is hard to beat IMHO. John have you tried NGC 7789 in the 12"/Leica? Higher power viewing of M42/M43 are stunning in this eyepiece under the dark conditions that enhance these views. This eyepiece has many uses that it excels at and it will barlow very high.

[John]

26 minutes ago, jetstream said:

.... John have you tried NGC 7789 in the 12"/Leica? ....

Not as yet Gerry - but it's on the radar now !

The most impressive views so far through the Leica / 12" dob / VIP barlow combo  have been of the globular clusters M13 and M92 in Hercules a few nights back.

At around 300x M13 seemed to fill a big chunk of the field of view and the view was stunning. The cluster was resolved right into the core and the tightly packed stars seemed to scintilate as I observed. I viewed M13 a few years back with a 20" dob from at the SGL star party and these views through my 12" dob reminded me strongly of that. M92 was really lovely as well. Well impressed

I'm really looking forward to M42/43 with this combination. Zooming into the Trapezium region is going to be a lot of fun !

[Pondus]

I got a question to you John, and those of you who happen to own the 31mm Nagler and 21mm Ethos (or similar 20mm ES/Lunt 100).

Which gets used most : 31mm 82 or 21mm 100 ? 

This Winter i could spend an entire session only using the ES20 ....

[John]

14 minutes ago, Pondus said:

I got a question to you John, and those of you who happen to own the 31mm Nagler and 21mm Ethos (or similar 20mm ES/Lunt 100).

Which gets used most : 31mm 82 or 21mm 100 ? 

This Winter i could spend an entire session only using the ES20 ....

For me it's the 21mm Ethos that gets much more use. I have some LP to contend with and the higher magnification does help pick out faint DSO's better. I've had several Autumn and Winter galaxy sessions with the 12" dob with the 21 Ethos in the focuser for the whole time

I still value the big Nagler though, especially on the really large DSO's such as the Veil.

Edit: I guess the above confirms that I should not include those two in any "downsizing"

[Piero]

It's an interesting question that comes up rather frequently when people get the E21 while owning the N31. I am sure John will give you a nice reply.

As far as I understand, it depends on target and telescope f-ratio. Owning an 8" F6 like yours, there is only 20x magnification difference and both the exit pupils are good with most of the skies. Therefore, like you, I also prefer my 20mm to the 30mm I own. In faster telescopes, the 30-31mm can have a rather large exit pupil, so unless one observes from a darker location, I believe these focal lengths will be mostly used with narrow or line filters. Of course these filters will also work (and will work better) under dark skies. 

 

EDIT: well, he already did!  

[Louis D]

4 hours ago, Pondus said:

I got a question to you John, and those of you who happen to own the 31mm Nagler and 21mm Ethos (or similar 20mm ES/Lunt 100).

Which gets used most : 31mm 82 or 21mm 100 ? 

This Winter i could spend an entire session only using the ES20 ....

I don't have a 21mm Ethos, but I do have a 40mm Meade SWA 5000 and a 30mm ES-82 and I prefer the views through the 40mm in all of my scopes despite the large exit pupil and somewhat lighter background simply because it is much easier to see 68 degrees at once rather than 82 degrees at once when scanning star fields, especially with eyeglasses and the super long eye relief of the 40mm.  That, and the 40mm is sharper at the edge than the 30mm.

I would love for ES to introduce a 22mm to 24mm version of their 92 degree line as has been hinted at on CN.  I have the 17mm ES-92, but it is only as wide as a 22mm 70 degree eyepiece.  It is a very engaging eyepiece, though.

[Pig]

7 hours ago, Pondus said:

I got a question to you John, and those of you who happen to own the 31mm Nagler and 21mm Ethos (or similar 20mm ES/Lunt 100).

Which gets used most : 31mm 82 or 21mm 100 ? 

This Winter i could spend an entire session only using the ES20 ....

In an SCT type scope the 31mm would give much tighter stars than the he 21mm and the 41mm Panoptic more so than both?

[Stu]

8 hours ago, Pondus said:

I got a question to you John, and those of you who happen to own the 31mm Nagler and 21mm Ethos (or similar 20mm ES/Lunt 100).

Which gets used most : 31mm 82 or 21mm 100 ? 

This Winter i could spend an entire session only using the ES20 ....

When I had both, the 21e got most time in the focuser definitely, but I could not bring myself to sell the 31n. It does bring something different to the party, particularly as John says under a dark sky where the extra field of view can be used without the larger exit pupil causing the background to wash out.

Despite not being a dramatically wider view, it can make the difference between fitting the whole Veil in comfortably and it just being a little too tight, worthwhile keeping for that alone really.

I also remember one session with SwampThing and Falksy with 14 and 16" dobs where is showed the Crescent Nebula better than the 21e. Must have been an exit pupil effect again.

[John]

I've posted an update on progress with the Leica zoom here:

https://stargazerslounge.com/topic/296066-leica-asph-zoom-question/?do=findComment&comment=3257496

I think I'll be hanging on to my other eypieces for a little longer yet.

[Pig]

John, as it happens I now have only 3 eyepieces and a Barlow for Astro observing. I could probably get away with just a single eyepiece for solar ?

[rwilkey]

Hi John, you will not enjoy the hobby so much without the variety of viewing choices - which I find very stimulating.  The ES experience is very different from the Pentax, for example. 

[John]

16 minutes ago, rwilkey said:

Hi John, you will not enjoy the hobby so much without the variety of viewing choices - which I find very stimulating.  The ES experience is very different from the Pentax, for example. 

I agree Robin. Different eyepieces have difference characteristics just like different types of scope do

[GavStar]

I think that this thread posts a thought provoking question.

After my recent visit to a dark site with my 130mm frac, I've been reflecting on my most used eyepiece set which consists of a Leica zoom, a 1.8x Leica extender, 21mm ethos, 17mm ES 92, 12mm ES 92, which is reasonably close to what John is considering (with a few extras!).

With the planets low in the sky, I've been focussing more on DSOs than I have before and its been a lot of fun and opened many new interesting objects. However at the recent session I was disappointed with the Leica zoom, I felt the fov at the low end was too restrictive for me and my other eyepieces presented the star fields in a much more attractive way to me. My initial reaction was to get an 8mm ethos to get the wider fov but with c100x magnification and only use the Leica zoom extender combo at the high power end. But I love the extra eye relief and comfort of the ES 92, so have decided that (for now and potentially until the 8.8mm and 6.5mm ES 92s come out next year) I will use my 2x Powermate with my 17mm and 12mm to get 8.5mm and 6mm. It creates a bit of a beast but I have done it before as an experiment and my focuser coped fine. I will also put my Leica away in a box for a while and for higher power use my 5mm Pentax xw as a replacement. So I seem to have gone the other way from using a zoom back to a set of 4 fixed eyepieces and a powermate.