78 replies to this topic

[Messyone]

How do you like your 40mm ES 68? Do you observe with the eyecup upwards or folded? How's the comfort, notice any annoying blackouts or stray light seeping into the eyecup when observing? I had a 40mm ES 62 once and that stray light part really annoyed me. As if the eyecup was too large to fit an eye socket and cover it properly. Maybe I should stop messing around and try this eyepiece.

I use every eyepiece I have owned with the cups folded down. Doesn’t matter how long the eyerelief. Zero blackouts and stray light was of no concern. Really liked the sharp field stop.
After selling everything in covid times except the ST 120 I started the eyepiece collection when I could and now use a TMB 40 68, with a morpheus original rubber eyecup…folded down of course. 
In 2017 I tried the TS field flattener which was of no use either. 

[Olimad]

The Photon 4.5" f/4 (TeleskopService) with a 2" focuser, paired with the future Houdini CC 28mm eyepiece, would offer around a 4.6° coma-corrected TFoV, with the scope and eyepiece weighting less than 2.7 kg and tube length of 380mm.

 

This setup would provide light grasp equivalent to a 106mm APO, with slightly less contrast.

 

If you want to do planetary with It, stack the APM CC 2,7x Barlow with a 5,5mm eyepiece and you get 2x aperture (230x).

 

If you can bear more weight, instead of the Photon 4.5", you can choose the Photon 6" F/4. At the cost of more weight and less TFoV, you will gain more aperture. The future Houdini 28mm, assuming a 36mm field stop, will provide a 3.5° coma-corrected TFoV.

Edited by Olimad, 26 April 2025 - 01:25 AM.

[Jon Isaacs]

I thought I'd see some 60-72mm f/5-7 Apo Refractors as favorites. It seems the consensus is 80-125mm f/5-6.

 

With big AFOV eyepieces in the 82-100º range. Mostly 20mm 100 XWA's, 22mm T4's, 28mm UWA and 31mm T5 Naglers instead of the 35-40mm range.

 

Interesting 

 

PS> Having said all that, do you guys like something like a 72mm f/6 APO for rich fields? As a very light grab n go.

 

You asked about one scope, one eyepiece.

 

My AT-70ED with the 41 mm Panoptic provides amazing views, 6.3° with a 6.8 exit pupil at 10x.. 

 

But it's hard to choose that one view over the NP-101 with the 31 mm Nagler.

 

70 mm to 22 inches, F/4.06 to F/6, they all provide awesome Rich Field views. The larger the scope, the more opportunities there are. With the 70 mm, the sky is broken up into 6° x 6° sections, with the 22 inch, the sections are 1° x 1°.. 

 

Jon

[Procyon]

My average guy set-up would be an AT80ED with a ES 28/68 on S/W AZ-GTi for 3.4* TFOV. My gadget would be an Oberwerk 20x70EDU on a 4000 tripod while I'm seated on a TeleVue Air Chair.

Good enough for me 

 

rsz_img_2464.jpg.

Nice scope. May I ask if there is a reason you prefer the ES 28/68 over an AT 28/82? Or did the cookie just crumble that way for you?   (To quote a famous New England football player J. Edelman). 

 

Debating whether I should go for an AT 28/82 or ES 30/82 but I have so many eyepieces that are dull black, my cases are starting to look lifeless. Always good when manufacturers add a touch of color to their ep's like Meade did with the 28//82 PWA and Celestron with their 30mm Ultima Edge Flat Field. At least ES adds a tiny green logo. 

Edited by Procyon, 25 April 2025 - 04:25 PM.

[Procyon]

In 2017 I tried the TS field flattener which was of no use either. 

How come?

[vtornado]

I might prefer a set of binos and a comfy high back chair, or  lounger.  I remember ... (a long time ago when I was a kid) Staring at the milky way with 10x50's in Bortle 2.   A "My God, It's Full of Stars" moment for a city kid.

 

Otherwise I like my Svbony 70mm f/6 ED refractor.    When using 2 inch eyepieces a field flattener would help, as stars in the center are in focus and at the edge not.  They are pricey little things though and with two inch eyepieces diagonal and now FR The rig is no longer cute.  Telescope excels over binoculars for the ability to change powers, less fatiguing to hold, and ability to share the view.   If your viewing is limited to 10x, then the binocular's view trump monoviewing.

 

Bino's get difficult to tripod mount and be comfortable, but can be done.

 

At low power a ST80 is fine.  Some have some optical issues so it is luck of the draw.

[CHASLX200]

My 110mm Tech and a 21mm Ethos.

[25585]

My APM LZOS 130mm F6 with a TSFlat2 (WO diagonal) and an ES68/Meade SWA 5000 34mm.

Attached Thumbnails

• 

[vrodriguez2324]

How did you try it? My experience so far with the TSFLAT2 is that it works really well in both the ST120 and the Evostar 72ED. I use it by threading it directly on the diagonal after unscrewing the nosepiece. I am surprised you didn't find it useful. To my eyes it does an excellent job of flattening the field in the ST120 + 31NT5. It does a little less well in the 72ED + 31NT5 but still performs very good and improves the view significantly.

I use every eyepiece I have owned with the cups folded down. Doesn’t matter how long the eyerelief. Zero blackouts and stray light was of no concern. Really liked the sharp field stop.
After selling everything in covid times except the ST 120 I started the eyepiece collection when I could and now use a TMB 40 68, with a morpheus original rubber eyecup…folded down of course. 
In 2017 I tried the TS field flattener which was of no use either. 

Edited by vrodriguez2324, 25 April 2025 - 11:36 PM.

[vrodriguez2324]

Nice scope. May I ask if there is a reason you prefer the ES 28/68 over an AT 28/82? Or did the cookie just crumble that way for you?   (To quote a famous New England football player J. Edelman). 

 

Debating whether I should go for an AT 28/82 or ES 30/82 but I have so many eyepieces that are dull black, my cases are starting to look lifeless. Always good when manufacturers add a touch of color to their ep's like Meade did with the 28//82 PWA and Celestron with their 30mm Ultima Edge Flat Field. At least ES adds a tiny green logo. 

 

You're right. The 28UWA (StellarVue model pictured) and the ES 30/82 have simple designs. Go for the 31NT5. It has clean sharp Tele Vue green pinstripes on the name ring. A perfect touch of color for your case.

Edited by vrodriguez2324, 25 April 2025 - 11:42 PM.

[Procyon]

Sure, it may sound fussy to want some different colors, but take a look at this:

 

 

It looks like a funeral but what's funny, is that only 1 one of these eyepieces comes to focus (Actually 5, but I don't see the 5, 9, 12 and 14 getting much use at the moment) in a 100mm f/6 refractor. So there's some opportunity in bringing in some new guys with color. Like a 22mm T4, not sure what else though atm. At least 1 in the 35-40mm range. I think it has to be a green Panoptic.

Edited by Procyon, 26 April 2025 - 01:05 AM.

[Astro-Master]

My favorite rich field scope is my ES 6" F/4.8 Mak-Newt with a 32mm 80* eyepiece with a power of 22.8x with a 3.5* TFOV, and an exit pupil of 6.6mm.

 

If I need a wider FOV I use my Stellarvue 60mm F3.5 finder scope with a 16Nagler for a 13x with a 6.2* TFOV.

[PKDfan]

I just recently finished optimizing my 62mm apo for low power work and ultrawide fields- 40XW at 10.1X and ~6 2/3 degrees true field with a 6 1/4mm exit pupil.

One upping my previous low power 30XW's 13.1X and 5.2degrees and a 4.65mm exit pupil.

When i get my 48mm Brandon--Thanks Procyon !! for helping me to get the Big Brandon over the goal line; gives me an ultralow 8.33X and a 7.44mm exit pupil which still fits within my fully dilated pupil but only(lol) a 5.5degree true field.

The big Brandon does a sweet 18.75X and a 5.33mm exit pupil and a Tiny ~2.4degrees true in my 100ED where i see it being most used.

Alas, I've yet to use either in really dark skies for the widefield sweeping that i desire.


I bought my short apochromat for the sole express purpose of dissecting M31 & M33 and the entire Veil and North American nebula.

The latter two i've yet to observe at all.

All the really BIG stuff was in the brief for my needs and wants so despite the small aperture of only 62mm i can get to binocular level powers with Just enough objective size illumination so that going from 8X or 12X 40mm binoculars doesn't feel similiar.

And for me that deftly bridges the gap between binoculars and telescopes but with just enough aperture to bring out (i do hope) a big satisfied smile.


If only i could easily reach dark skies !



CSS
Lance

[Jon Isaacs]

My APM LZOS 130mm F6 with a TSFlat2 (WO diagonal) and an ES68/Meade SWA 5000 34mm.

 

I calculate the TFoV of that combination based on the 38.6mm field stop to be 2.84 degrees.  Andromeda should fill the field.  

 

Jon

[CHASLX200]

Best deep sky nite for me was in Jan 1979 in a Mag 7 sky before FL was built over at 1 am till 4 am with a 6" F/4 RFT Newt and a 28mm RKE.  Only if i had a 2" focuser and a 21mm Ethos back then.  I swept up so many Galaxies from M3 to M68 it was unreal.

[bobhen]

The intensifier causes the reduction to f/3.5? Have their been improvements to remove static and that Gulf War green image? How do the views look like?

 

There's no way to add a focal reducer to a 100mm f/6 achro without causing vignetting in the eyepiece right? I keep reading a telocentric barlow would be best, but no screwable lenses exist. Or simply aren't possible to make?

 

PS> I was looking into if I can somehow barlow a 48mm Brandon since I like this eyepiece so much. Ultimately, I'll probably be better off getting a beloved 22mm T4 Nagler again.

For Night Vision observing using my intensifier...

 

No. I use a 2". 7 reducer. The reducer causes the reduction.

 

Yes. Some modern intensifiers have gain control. That helps remove scintillation. Some modern intensifiers have a white tube and impart a white/cool image.

 

For night vision, my reducer is placed very close to the intensifier in the optical train. There is some very very slight vignetting but it is not in the least distracting. The views in the intensifier are so captivating and impressive that any minor optical imperfections do not distract from the view – really.

 

One can use a standard Barlow to increase magnification, if so desired. I have used both standard and Powermate image amplifiers. I have also used just the lens of a 2" Barlow to increase magnification.

 

For more in-depth answers to any questions head over to the Night Vision Forum. There are pinned topics at the top of that forum.

 

Bob

[JohnnyMac]

Best deep sky nite for me was in Jan 1979 in a Mag 7 sky before FL was built over at 1 am till 4 am with a 6" F/4 RFT Newt and a 28mm RKE.  Only if i had a 2" focuser and a 21mm Ethos back then.  I swept up so many Galaxies from M3 to M68 it was unreal.

That's what David Levy uses. According to the net.

[Procyon]

So I went to order an AT70ED from Astronmics and some accessories but they no longer ship to Canada because of some agreement...I used to order from them, so I don't know what happened there. Guess I'll have to look around for one. Any other dealers that sell the Astro-Tech brand? That TS Optics 70 f/6 real doublet looks good too.

 

PS> Does anyone know if there's a huge difference for low wide field observing between an AT70ED and an AT72EDII? Optics wise I mean, I must have a Vixen rail bar and rings somewhere...I have zero intention of going over 35-50x with these scopes as I use a CPC 1100 for over 50x and binoviewers for planets..

 

Now to find a 22mm T4, 28mm AT82, 35mm Pan...I know for sure these 3 will come to focus in my refractor, too bad the 31mm Nagler won't. Probably because the TSFLAT2 field corrector adds about 7mm of back focus.

 

There goes all the extra money from 4 months of GIC - CD gains.  

Edited by Procyon, 26 April 2025 - 11:16 AM.

[C. Evangelista]

 

Now to find a 22mm T4, 28mm AT82, 35mm Pan..

To keep it cheap, just try the Baader Hyperion Aspheric 31mm and/or 36mm.

 

They work well for wide field in my LZOS 130 f/6

[Procyon]

To keep it cheap, just try the Baader Hyperion Aspheric 31mm and/or 36mm.

 

They work well for wide field in my LZOS 130 f/6

I had the 31mm Baader Aspheric 12? years ago...something about it bothered me, so I sold it.

[CHASLX200]

That's what David Levy uses. According to the net.

It was nuts in Coma and Virgo.

[C. Evangelista]

I had the 31mm Baader Aspheric 12? years ago...something about it bothered me, so I sold it.

Yes, the 31mm and 36mm Hyperions display really good contrast and transmission, but sharpness is better in Panoptics, Naglers, Masuyama 32mm...

[HellsKitchen]

This looks interesting, Skywatcher 6" F/4 with an included coma corrector that brings it down to F/3.45.  4 deg field with a 21mm Ethos @ 6mm exit pupil. ST80 fields with 6" of aperture...

 

https://www.firstlig...-corrector.html

 

Anyone tried this visually?

Edited by HellsKitchen, 26 April 2025 - 07:18 PM.

[thecelloronin]

My Megrez 90 and 40 Paragon clone make a sweet combo for RFT... 4.72° at 14x is pretty expansive. That said, if I was relegated to a single eyepiece, I think I'd miss the 22T4 @ 3.23° and 25x.

[Jon Isaacs]

I had the 31mm Baader Aspheric 12? years ago...something about it bothered me, so I sold it.

 

Lots of off-axis astigmatism.  And it's not "cheap", it costs more than the Astro-Tech 28mm UWA and the SkyRover 30mm UFF and both of those are much sharper off-axis.

 

Jon