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What did you observe with your classic telescope today ?

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#5251 Bomber Bob

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Posted 24 January 2020 - 06:49 PM

Clear skies tonight, and no Moon, so DSOs for Ol' BB.  Got my favorite EQ g&g rig:  AT102ED + Tak FC-50 + Mizar AR-1.  As usual, I'll be looking, but I'll also be testing:  Bought new accessories from our Sponsor and from Sheldon.  The most interesting to me is a Bushnell 18mm Wide Field (68*) Kellner.  Looks like someone adapted a large binocular eyepiece to black anodized 1.25" cap & barrel.  But... it doesn't look like a "BB ATM Special" -- more professional & commercial-grade than that.  I'm curious to see how it does against my spectros Big Kellners, which have true 100% edge-to-edge flat fields.

 

I'm really loving this combo:

 

AT102ED S21 (AR-1 & FC-50).jpg

 

When I was a crazy teenager, I scavenged 2 similar bino eyepieces.  They were too large for .965" barrels, so I adapted them to 1.25" ones, and used them with my 8" F4.5 Newt.  Yeah... a marginal BB-made mirror + iffy quality old EPs with failing coatings...  The views weren't high quality.  I predict that this KE18 will do much better in both of my APOs.  Almost forgot (yeah, Big Surprise!), I also tested a new AT 15MM 1.25" PARADIGM DUAL ED eyepiece.  From AT's ad:  "With a short focal length refractor it is a medium to low power eyepiece well suited to scanning the teeming star clouds of Sagittarius."  I used it most in the Tak FC-50, and found that description accurate.  Very nice eyepiece for the price.

 

BLUF:  A late night, where I learned that while ED glass is good, Fluorite is far better.  A portable rig with 2 quality refractors is a must for in-city backyard observers.  AND, when I can see the Milky Way at The Swamp, it's gonna be a very good time!

 

Both refractors had 99% yada yada yada mirror diagonals all night -- 1.25" in the Tak, 2" in the AT102ED.  

 

Venus:  I set up behind the shed at sundown to both block the wind, and give me a clear view of Venus.  Both fracs at 100x:  Nagler 7 in the AT102, Radian 4 in the FC-50.  No disk detail in either.  Venus is a harsh brilliant white in the FC-50, a cooler white in the AT102.  Zero (0) fringing in the FC-50.  Slight blue rind in the AT102 -- especially if my eye strayed a fraction of a millimeter off axis...

 

Star Test:  I turned to Capella, removed the diagonals, and tested both fracs.  No obvious issues with either frac at 80x in the FC-50 (spectros PL5), and at 120x in the AT102 (UO HD OR6).  Diagonals in with the same EPs, and similar results.  It was at focus that I saw a difference.  Here, I have to give a Shameless Plug for Our Sponsor:  The AT 1.25" diagonal is a very good buy compared to other mirror diagonals.  Capella's color at the EP matched what I saw eyeballs-only.  It was slightly redder in the AT102 with the ES 2" unit.  So, I paused, fitted the AT to it, and got a view that was closer to the FC-50.  By that, I attribute some small % of the red to the Scope & the OR6.

 

Milky Way:  After the testing, I looked up and saw a faint ragged cloud running from the NE to the SW.  "Oh, great!  Cirrus is sneaking in ahead of the wrap-around clouds!"  I thought some other things, too -- but can't post them.  Anywho, this cloud band wasn't moving at all, and I realized it was the Milky Way.  For once, my neighbors were home, and didn't have their prison-grade security lights on, and that helped a lot.  Behind the shed, I have a wide E-W belt of clear sky, but limited polar access.  I immediately dropped both fracs down to ~ 25x, and moved the rig to the SE corner of the yard.  That gave me clear skies from Perseus to Monoceros, and I could trace the MW easily.  I started out with Sheldon's Wide Field 16mm Kellner in the FC-50, and a 2" GSO 26mm WF KE in the AT102.  From the Unicorn, I moved slowly north.  Using the FC-50 as a finder, it took me a minute or two to find M50, which is sparse in this scope -- the bright orange star, and the brightest blue-white members stood out though.  Richer in the AT102 of course.  Zig-zagged slowly, and the fields got richer.  I had the eyepieces positioned so I could look quickly from one to the other without injuring my eye.  It was in Gemini & the north portions of Orion that I got my mind blown -- dozens of stars in the FC-50, and maybe hundreds of stars in the AT102.  That extra 50mm of aperture goes so much deeper, while both fracs present individual stars as micro-dots.  M35 is pretty in the 50, and glorious in the 102.  Interesting to me is swinging away from side-to-side, and seeing the Milky Way taper off.  The boundaries seem small & thin, but we now know just how huge those spiral arms really are...

 

A GREAT Orion Nebula:  I knew from the satellite that the southern ragged edge of the wrap-around clouds would eventually wreck the session, so waiting for Orion to hit the meridian was a nail-biter.  I moved the rig to the NW corner for its southern exposure.  While I waited, I turned to M79.  It is a very unremarkable globular, but it was the first one I observed with my new Tasco 80mm F15 EQ in the winter of 1978.  I centered on M42 as soon as it was past the huge pine tree half a block down the street.  At 25x in both fracs, that region is eye-popping.  In the perfect seeing, the Nebula reaches out across black space like it's trying to grab as many stars as it can.  My "serious" observing was on the Trapezium first.  The Tak showed 4 stars, with a clean black gap between A&B at just 25x with that WF KE16.  The AT102 also showed the 4 straight-on, while F popped into view with averted vision.  At 80x I got 4 pretty Airy Disks in the FC-50, and E&F with averted vision in the AT102.  (In my APM152, all 6 stars would have been visible straight-on with this perfect seeing.)  Upping the AT102 to 180x with the Radian 4 didn't add any more stars.  But, I could trace so many thin black lanes -- a very sketch-worthy view.  The Tak surprised me in that M43 was distinct from The Monster at 100x with the Radian 4.  The relatively wide flat field of these TV eyepieces has made a believer out of me.  (I'll still never pay for a brand new one, though.)  Honestly, I enjoyed exploring M42 more with the Tak + Rad4 than at higher powers in the AT102.  I couldn't see as much, but what I could see was sharply resolved, and the few red / orange field stars were so distinct.

 

Sure enough, while enjoying Orion, the wind picked up, & the air got damper.  I shook both fists at The Gods, then moved back to Home Plate behind the shed, and literally watched Zeus turn his dimmer switch!  Fainter stars went out, and the Milky Way dissolved.  I managed to grab the Beehive -- filled the Tak's field, and extended beyond the 102's.  Spent about a half-hour on doubles in Cancer to Hydra, then packed up.  But after weeks of overcast, or cloud-dodging at best, the 4 Seasons summed it up:  Oh!  What a night!  My only regret:  I didn't take 10 minutes to set up the Meade 826 on the patio.  That big Newt would've ripped the Milky Way apart -- in a good way.


Edited by Bomber Bob, 25 January 2020 - 01:00 PM.

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#5252 Esso2112

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Posted 25 January 2020 - 10:01 AM

Had a beautifully clear night last night. Spent a couple hours imaging, although I really was just testing a focus motor and not doing any serious images.  Then, I switched out scopes and had first light for an AP Traveler that I recently picked up. Spent about 1 hr looking at the Orion Nebula with various eyepieces and magnifications.  The trapezium easily showed the A, B, C, D, and E stars with a 6mm ortho.  The F star peaked in and out.  Sirius was used to test for any spurious color (none observed). By this time is was down in the low 40’s and I was getting cold.


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#5253 Bomber Bob

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Posted 25 January 2020 - 06:15 PM

Too bad it's not 2-3 hours past sunset NOW -- seeing would be like last night.  But, no!  By the time astro-night swings around, those thin knotted "fingers" from the SW will be here to muck-up our blue skies.  If I go out at all, it'll be cloud-dodging.  So, I have my 6336 (for doubles & open clusters) and my Edmund 6" F4 Newt (for deep sky) waiting patiently in the shed...

 

I did go out.  I did dodge clouds.  I did test all this new 1.25" stuff in a 1964 Royal never meant to use this format.  I saw all the advantages of 1.25" modern accessories in a vintage high-quality refractor (and there are lots of advantages!).


Edited by Bomber Bob, 25 January 2020 - 11:02 PM.


#5254 oldmanastro

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Posted 25 January 2020 - 07:04 PM

It looked promising earlier today but it's cloud covered now. A couple of days ago I had a break, took my Sears 6305 out and had a great time observing M42, M41, Rigel and other Messier objects in the beautiful clear winter skies. Eyepieces used were 1.25mm Plossl with an adapter. A Carton lens based 60mm f/17 that I assembled a few years ago was also used mounted in the 6305 equatorial mount. This telescope has exquisite optics. It is always a pleasure to observe difficult doubles with it. I consider it a modern vintage. The Sears 6305 objective lens is very good but not up to the quality of the Carton objective.

 

The great thing about these scopes is that you pick them up and have them ready in a heart beat and now retired and nearing 70 anything easier to handle is well.. great!

 

Clear Skies!

 

 

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#5255 Bomber Bob

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Posted 28 January 2020 - 07:17 PM

About to start cloud-dodging with the Triple Nickel (weird 5" F5 triplet).  Tonight's experiment:  Can the VersaGo carry this mini-Beast?  I attached it's hinged rings to either end of a 14" dovetail, put that on the mount first, and got it tight as possible without breaking the plastic handle, before loading the OTA.  So far, so good.  Also, gonna test the ES 2" Disco-electric diagonal, and the E-Lux 2" eyepieces... 

 

Crescent Moon was sharp with the 26mm at a whopping 25x.  Goofy as it is, it's still a 5" lens, and is sharp in the center.

 

Almost horizon to horizon gap, with 8+ seeing, when I first went out, and the TN grabbed M35 - M38 at 1830L (0030Z).  M37 was the toughest, but after looking at it directly for a few minutes, the dozens of faint members popped in & out of view -- incredibly small pinpoints.

 

I love sweeping with this scope, and it's so dang easy on the VersaGo -- just gotta keep it Balanced & Level.  I swept from Auriga to Cassiopeia, and back again, in wide bands -- scooping up the views.  Dozens of super-rich star clouds / fields.  The Double Cluster is spectacular -- twin crowns in a very rich field -- even that tight trio of fainter stars is resolved.  My last sweep took me south to Taurus, then west to the Pleiades.

 

After a busy work day, this goofy scope makes for a calmer night.


Edited by Bomber Bob, 28 January 2020 - 10:29 PM.

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#5256 rcwolpert

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Posted 29 January 2020 - 11:50 AM

Well, while recovering from my 2nd open heart surgery in 6 years (this time for a mitral valve repair), I haven’t been able to move a telescope outside for viewing. However, viewing the SpaceX launches from my chair has been fun. Today I used my 25x100 Binos to view the SpaceX Starlink launch from about 10 sec after launch until after main stage separation. These launches are always amazing to watch. In another few weeks I should get out with the telescopes again.


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#5257 Bomber Bob

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Posted 29 January 2020 - 12:02 PM

Youch!  Take care down there Bob!!


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#5258 rcwolpert

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Posted 29 January 2020 - 12:27 PM

Youch!  Take care down there Bob!!

Thank you!  I hope this was the last one! waytogo.gif


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#5259 Augustus

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Posted 29 January 2020 - 06:31 PM

Took the C8 out for a little under an hour tonight to test. I'm going to the Westport Observatory tonight; otherwise I'd have taken the 8 to Ward. Images are better than ever.

 

 


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#5260 ccwemyss

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Posted 29 January 2020 - 10:05 PM

Took the Pentax out to look at the moon. Pushed it up to 208X and it was still asking for more. I've never seen the point of a 4mm eyepiece before this, and may need to get one now. Atlas and Hercules had some amazing detail. 

 

Looked at Venus with a ND filter, which gave a clear, slightly gibbous phase. But it was low, with atmospheric refraction adding color. 

 

Also looked at M31, M32, and M110. Then the double cluster, Pleiades, M44, M45, M42 (the E component of the trap was clearly visible, and the F was there with averted vision), and ended on M81 and M82. Every one of them was gorgeous, with pinpoint stars all around. 

 

The K25 is wider than I expected. It seems to be 50* AFOV with a TFOV of 1.25* at 1000mm.

 

Now that the controls are engaging the flats on the posts, the mount is moving more smoothly. But the RA cable gets into some annoying positions. I may order a couple of knobs from McMaster and turn it into a setup with a knob on each side, like the 142. I'd love to find a drive for it. 

 

I also need to figure out how to focus the polar finder, which is just showing donuts for stars. 

 

Chip W. 


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#5261 Bomber Bob

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Posted 30 January 2020 - 10:02 PM

A very short repeat tonight with my Triple Nickle.  The waxing crescent Moon was in about the only gap in the increasingly overcast sky.  Not a bad thing this time, as I found out that this 5" F5 triplet (military camera?) lens, will stay sharp at up to 270x -- so long as I keep the lunar feature(s) I want to observe near the center of field.  It's no substitute for any of my 4" & larger astronomical telescopes, but it's more versatile than its optics might suggest...

 

OTOH, when I tried imaging Saturn with it, I could not keep the planet at the exact center of the field & the chip, and it was a technicolor mess!


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#5262 Terra Nova

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Posted 30 January 2020 - 10:14 PM

A very short repeat tonight with my Triple Nickle.  The waxing crescent Moon was in about the only gap in the increasingly overcast sky.  Not a bad thing this time, as I found out that this 5" F5 triplet (military camera?) lens, will stay sharp at up to 270x -- so long as I keep the lunar feature(s) I want to observe near the center of field.  It's no substitute for any of my 4" & larger astronomical telescopes, but it's more versatile than its optics might suggest...

 

OTOH, when I tried imaging Saturn with it, I could not keep the planet at the exact center of the field & the chip, and it was a technicolor mess!

How is it for star fields at low power? I would think it would be a nice rich field refractor for expansive views, clusters, and other expansive DSOs like M31, M42 etc. It the field flat at low power! Pin cushion?


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#5263 Bomber Bob

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Posted 30 January 2020 - 10:28 PM

How is it for star fields at low power? I would think it would be a nice rich field refractor for expansive views, clusters, and other expansive DSOs like M31, M42 etc. It the field flat at low power! Pin cushion?

It is glorious at 25x.  Crazy wide with a vintage Edmund 2" 30mm Erfle!  It made my 4" Jaegers redundant -- so that's going to the grandkids this weekend.  Yes, micro-dot field stars; and, those faint members of M37 are even smaller & sharper.

 

Out in the country, it'll easily out-perform the Jaegers on faint fuzzies, and that scope was no slouch.


Edited by Bomber Bob, 30 January 2020 - 10:29 PM.

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#5264 Terra Nova

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Posted 30 January 2020 - 10:54 PM

It is glorious at 25x.  Crazy wide with a vintage Edmund 2" 30mm Erfle!  It made my 4" Jaegers redundant -- so that's going to the grandkids this weekend.  Yes, micro-dot field stars; and, those faint members of M37 are even smaller & sharper.

 

Out in the country, it'll easily out-perform the Jaegers on faint fuzzies, and that scope was no slouch.

Sounds great! I would think it perfectly suited for that! I’ve had a couple of the Orion Synta 120mm F5s over the years and they were great fun RFTs. My last one was redundant with my Vixen 120mm Petzval F6.67 so I sold it but I always have my 6” F4.5 Newt RFT.


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#5265 Bomber Bob

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Posted 31 January 2020 - 06:16 AM

Here's the deal with this 5" F5 triplet:

 

- Color Correction is excellent from edge to edge;

- Field Curvature smears objects moving out from the center.

 

I think this thing had a correcting lens assembly behind it to flatten the field.  Originally?  Could've been a gov't (military or civilian) camera; or, could've been a wide angle astro camera.

 

The other night, while I was in Auriga / Taurus, 2 very bright fireballs swept across the field.  One was orange, the other yellow-orange.  As they entered the field, they were stretched into comets, became stellar at the center, then smeared again exiting; but, the colors did not change.

 

Anywho, this oddball makes a great RFT, so long as you accept its issues.  It makes an okay medium to high power frac, as long as you keep the target dead center.  Someone thought enough of the lens to keep it, and put it in an attractive tube assembly.  I tend toward a military origin because I know from experience that DoD will pay top $$$$ for glass like this.  And, we know Ralph Dakin kept the "scraps" from B&L.  This is the kind of thing I'd take home from a Depot -- if that was allowed.


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#5266 Senex Bibax

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Posted 31 January 2020 - 07:33 AM

What I wouldn't give for temperatures in the low 40's F now. I was out on Wednesday just after sunset here in Ottawa, with my C90 and Sears 6309, beautiful clear skies. The temperature was -9C, and by the time i packed up an hour later with numb fingers, it was -12C (10F). I did manage some good views of the crescent moon and Venus, but the sky wasn't dark enough yet for the Orion Nebula.

 

I did get a naked eye view of the ISS passing in the northern sky, and what I think was an Iridium flare.

 

Had a beautifully clear night last night. Spent a couple hours imaging, although I really was just testing a focus motor and not doing any serious images.  Then, I switched out scopes and had first light for an AP Traveler that I recently picked up. Spent about 1 hr looking at the Orion Nebula with various eyepieces and magnifications.  The trapezium easily showed the A, B, C, D, and E stars with a 6mm ortho.  The F star peaked in and out.  Sirius was used to test for any spurious color (none observed). By this time is was down in the low 40’s and I was getting cold.


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#5267 Garyth64

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Posted 31 January 2020 - 08:15 AM

Someone please explain to me what "stars" are.  And what is this thing that is called "Moon"?

 

(it has been a long time that I could do any observing because of the Michigan "Nebula".)


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#5268 Terra Nova

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Posted 31 January 2020 - 03:27 PM

Here's the deal with this 5" F5 triplet:

 

- Color Correction is excellent from edge to edge;

- Field Curvature smears objects moving out from the center.

 

I think this thing had a correcting lens assembly behind it to flatten the field.  Originally?  Could've been a gov't (military or civilian) camera; or, could've been a wide angle astro camera.

 

The other night, while I was in Auriga / Taurus, 2 very bright fireballs swept across the field.  One was orange, the other yellow-orange.  As they entered the field, they were stretched into comets, became stellar at the center, then smeared again exiting; but, the colors did not change.

 

Anywho, this oddball makes a great RFT, so long as you accept its issues.  It makes an okay medium to high power frac, as long as you keep the target dead center.  Someone thought enough of the lens to keep it, and put it in an attractive tube assembly.  I tend toward a military origin because I know from experience that DoD will pay top $$$$ for glass like this.  And, we know Ralph Dakin kept the "scraps" from B&L.  This is the kind of thing I'd take home from a Depot -- if that was allowed.

You might try more modern eyepiece designs than the Erfle to minimize the field curvature/radial distortion. (We called it radial distortion (displacement actually) when I was doing photogrammetry from aerial photographs.)


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#5269 Bomber Bob

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Posted 31 January 2020 - 06:28 PM

You might try more modern eyepiece designs than the Erfle to minimize the field curvature/radial distortion. (We called it radial distortion (displacement actually) when I was doing photogrammetry from aerial photographs.)

Modern?  Bite your tongue!  This is the Classics Forum!  I bought that used set of 3 Celestron E-Lux 2" eyepieces.  Not quite vintage, but using a vintage design -- Modified Achromatic / Kellner.  What I need:  A 2" eyepiece design that'll do well in both an F5 refractor & an F4 reflector, since both suffer from coma -- a big factor at low powers.



#5270 Terra Nova

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Posted 31 January 2020 - 07:08 PM

Modern?  Bite your tongue!  This is the Classics Forum!  I bought that used set of 3 Celestron E-Lux 2" eyepieces.  Not quite vintage, but using a vintage design -- Modified Achromatic / Kellner.  What I need:  A 2" eyepiece design that'll do well in both an F5 refractor & an F4 reflector, since both suffer from coma -- a big factor at low powers.

 

While your vintage Edmund 2" 30mm Erfle may be a cool old classic eyepiece, it’s a good example of one that would not help with the field curvature/radial distortion of your 5” F5. Now Naglers have pretty much become classics by now and they would do a much better job. Even better if you want to go more modern would be an Ethos or Pentax XO, all of which incorporate elements with additional negative surfaces to help flatten and rectify the field.

 

 

Lens design diagrams from: https://www.handprin.../ASTRO/ae5.html

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Edited by Terra Nova, 31 January 2020 - 07:10 PM.

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#5271 Uranotopia

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Posted 31 January 2020 - 07:20 PM

Of course the modern eyepieces are better, but nevertheless I am really astonished about the quality of the old Erfle design (although field curvature is worse in comparison with modern eyepieces) ! In Wikipedia it is told, that this optical design is from 1917 - what was the birthday of my Grandma!!!
But I also have seen some poor Erfles, not in such a good quality (of course these were "made in China"...)


Edited by Uranotopia, 31 January 2020 - 07:22 PM.

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#5272 Terra Nova

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Posted 31 January 2020 - 07:35 PM

Of course the modern eyepieces are better, but nevertheless I am really astonished about the quality of the old Erfle design (although field curvature is worse in comparison with modern eyepieces) ! In Wikipedia it is told, that this optical design is from 1917 - what was the birthday of my Grandma!!!
But I also have seen some poor Erfles, not in such a good quality (of course these were "made in China"...)

Hey, I agree! I have several Erfles from 20mm to 32mm and they are great in longer scopes. I wouldn’t part with the ones I have. But when you get down to F4 or F5 they start to really show their shortcomings if you’re using them with a scope that doesn’t have a field flattener.


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#5273 Joe1950

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Posted 31 January 2020 - 08:18 PM

I have a 20mm Edmund Erfle. I'm hoping it will give a good view in the C-8 @ F/10. That's 100X.


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#5274 ccwemyss

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Posted 31 January 2020 - 08:21 PM

Nagler type 1s are now up to 40 years old (I have several that I bought around 1984). Type 2s are up to 34 years old. They also had a line of Plossls that goes back to 1980. They are contemporaneous with the Koenigs that we seem to think of as classic. 

 

Definitely meets the 25 year forum rule for classic. Perhaps we are biased against thinking of them as classic because they are still around in newer versions, and there aren't any examples you can by from a maker who is out of business. 

 

I was just out using the T1 Nagler 7 and 4.8 in the Pentax a couple of nights ago. The 4.8 gave the best views of the moon, and also allowed me to pick out the F component of the trap. The only thing I have to remember is to take my glasses off when I use them, not because of the eye relief, but because they scratch the daylights out the lenses. 

 

Chip W. 


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#5275 Defenderslideguitar

Defenderslideguitar

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Posted 31 January 2020 - 08:38 PM

I bought my first additional eyepiece in 1984    the Nagler 4.8     still have it somehow


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