Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Wide field eyepiece for Vixen VMC 200L

  • Please log in to reply
8 replies to this topic

#1 Simply Peter

Simply Peter

    Sputnik

  • -----
  • topic starter
  • Posts: 27
  • Joined: 03 Aug 2018
  • Loc: Santa Fe, NM

Posted 11 September 2019 - 08:37 AM

I am contemplating the purchase of a Vixen VMC 200L.  I have a Meade 40mm HD-60 eyepiece which should give me 49x with a field of view of .82 degrees.  I am looking for suggestions for an eyepiece that will provide a wider field of view.



#2 Starman1

Starman1

    Vendor (EyepiecesEtc.com)

  • *****
  • Vendors
  • Posts: 42416
  • Joined: 23 Jun 2003
  • Loc: Los Angeles

Posted 11 September 2019 - 01:18 PM

Focal length is 1950mm.

Maximum field of view with 1.25" eyepieces = 0.80° with 27.2mm field stop

[TF = eyepiece field stop/telescope focal length x 57.296]

Maximum field of view with 2" eyepieces = 1.37° with a 46.5mm field stop

 

The HD-60 eyepiece doesn't come in a 40mm size.

The older Series 5000 Super Plossls in the 1990s came in a 2" 40mm with about a 38mm field stop.

The newer Series 4000 Super Plossl comes in a 1.25" 40mm with a 27.0mm field stop.

 

So it looks like you are going to convert to a 2" star diagonal and a 2" wide angle eyepiece to get a wider true field at 40mm.

The scope is 2" capable.

There are many choices for that eyepiece.  See the Eyepiece Buyer's Guide, pinned at the top of the Eyepieces Forum.



#3 Simply Peter

Simply Peter

    Sputnik

  • -----
  • topic starter
  • Posts: 27
  • Joined: 03 Aug 2018
  • Loc: Santa Fe, NM

Posted 11 September 2019 - 01:55 PM

I have had the Series 5000 5 element plossl that has a 60 degree field of view.  I assumed it was a HD-60.  I believe that I bought it in 2011 perhaps it was old stock?



#4 SeattleScott

SeattleScott

    Fly Me to the Moon

  • *****
  • Posts: 5689
  • Joined: 14 Oct 2011

Posted 11 September 2019 - 02:15 PM

I bought the 26mm series 5000 around 2005.

#5 Starman1

Starman1

    Vendor (EyepiecesEtc.com)

  • *****
  • Vendors
  • Posts: 42416
  • Joined: 23 Jun 2003
  • Loc: Los Angeles

Posted 11 September 2019 - 02:50 PM

I have had the Series 5000 5 element plossl that has a 60 degree field of view.  I assumed it was a HD-60.  I believe that I bought it in 2011 perhaps it was old stock?

Yes, it was old stock.  That's a 2" if I recall.

True field in that scope around 1.12°

You can't get a lot wider, but a 68° 40mm widefield would allow you to maximize the field in that scope.



#6 SeattleScott

SeattleScott

    Fly Me to the Moon

  • *****
  • Posts: 5689
  • Joined: 14 Oct 2011

Posted 11 September 2019 - 03:51 PM

38mm 70 degrees is a popular budget option. Vixen 42 LVW is higher end and relatively light. ES 40/68 is a good performer, just heavy. 41 Panoptic might be the best option right now, but naturally rather expensive, and heavy. They recently had a clearance sale on the 40mm Maxvision

#7 Simply Peter

Simply Peter

    Sputnik

  • -----
  • topic starter
  • Posts: 27
  • Joined: 03 Aug 2018
  • Loc: Santa Fe, NM

Posted 15 September 2019 - 03:00 PM

The deal on the VMC I was looking at fell through so I ended up buying a Vixen VC 200L with a focal length of 1800mm.  The Panoptic eyepieces are out of my price range. I currently have a 31mm Baader Aspheric 72 degree FOV and the Meade 40mm 60 degree FOV plossl.  I am wondering about adding something in the 50+mm range I know Meade makes a 55mm and Tele Vue makes a 56mm. I'm wondering about peoples opinion on these and whether there are other options.



#8 Starman1

Starman1

    Vendor (EyepiecesEtc.com)

  • *****
  • Vendors
  • Posts: 42416
  • Joined: 23 Jun 2003
  • Loc: Los Angeles

Posted 15 September 2019 - 04:41 PM

If you can afford the TeleVue, it is excellent in that focal length.

TV makes the 55mm and Meade makes the 56mm--you had it reversed.

Look for used ones, and you can save a bundle.

 

The VC-200L is a very different beast.

Specs:

Optical Design: VISAC Aspherical Mirror Reflector
Aperture: 200mm
Focal Length: 1800mm
Focal Ratio: f/9.0
Back Focus (from rear edge of focuser body): 149.0mm for optimum control of spherical aberration and adherence to the focal length.
Back Focus with Reducer (from rear edge of reducer): 63.5mm
Coating: Multi Coated (lens), Enhanced (mirrors)
Resolving Power ;.56 arc sec
Limiting Magnitude: 15.6 at a pristine site
Light Gathering Power: over 1000x the eye.
Adapter Thread: 60mm/50.8mm
Astrophotography: Prime Focus, Eyepiece Projection & Afocal Imaging
Visual Back: Compression Ring,
Tube Length: 23.6" (600mm)
Optical Tube Diameter: 9.1" (232mm)
Optical Tube Weight: 13.2 lb
Accessories; Dove Tail Mounting Rail; Carry Handle; Flip Mirror Diagonal;

** the flip mirror diagonal has a 49mm thread on the front.  To use 2" filters, get a 49mm male to 48mm female ring from a camera store to reduce the thread size for 2" filters.

This scope has a flat field, unlike the VMC-200, so It was a good choice.



#9 Simply Peter

Simply Peter

    Sputnik

  • -----
  • topic starter
  • Posts: 27
  • Joined: 03 Aug 2018
  • Loc: Santa Fe, NM

Posted 17 September 2019 - 07:58 AM

Don,

Thanks for the information, I am looking forward to receiving the scope and seeing what it reveals that my 120mm Apo was unable to.  




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics