Jump to content


Photo

SV F60M2 Finder Scope

  • Please log in to reply
11 replies to this topic

#1 Ed Whitney

Ed Whitney

    Messenger

  • -----
  • Posts: 472
  • Joined: 08 Jul 2010
  • Loc: Palm Coast, Florida

Posted 09 December 2012 - 10:52 AM

Hi, Does anyone have any experience using this finder?

The thing I am most concerned about is, are the stars at the edge of FOV in sharp focus like the center? Or, is there any issue here because the scope is a fast F/3.75?

And what was the faintest magnitude you were able to see? Is the brightness level of the scope adaquate, because it uses a prisim instead of a diagonal?

Thanks :)

#2 desertlens

desertlens

    Viking 1

  • *****
  • Posts: 825
  • Joined: 06 Dec 2010
  • Loc: 36°N 105°W

Posted 09 December 2012 - 11:22 AM

Ed,
I use an SV60 finder on my 80mm scope for observing rather than finding. Long story short... with orthos. I tried a number of wide field EPs, including a 19mm Panoptic and was disappointed with the edge of field performance. The performance of this scope and the orthos came as a surprise to me, very clean across the whole field. At present it contains an 18mm BGO + a Baader M&SG filter that basically lives there. The filter helps to tame the background a bit at these exit pupils. Brightness is not an issue. I used this setup last night to observe the entire sword of Orion and have used a 25mm UO Abbe with an OIII filter to see the entire Veil nebula. Just a technical note: The UO orthos in 18 and 25mm FLs will need a bit of help to come to focus. I use parfocalizing rings to accomplish this. This isn't necessary with the BGO or any of the other UOs. I'm uncertain of the limiting magnitude but it should be comparable to any 60mm binoculars.

#3 tomharri

tomharri

    Messenger

  • *****
  • Posts: 469
  • Joined: 19 Sep 2008
  • Loc: USA

Posted 09 December 2012 - 11:50 AM

The one I had was so bad the stars looked like seagulls. Trying higher power lenses just made everything worse.

But, on ebay, Russel Optics sells a 60mm binocular part with the exact same lens diam., same f/L, same thickness, same blackened edge......BUT this one performs like you had hoped the overpriced S.V. shoulda.

Sure you gotta cut the lens outta the housing, all glued together, but it is worth it at $24.95 to salvage this 60mm mess.

#4 desertlens

desertlens

    Viking 1

  • *****
  • Posts: 825
  • Joined: 06 Dec 2010
  • Loc: 36°N 105°W

Posted 09 December 2012 - 12:03 PM

Just for grins, here's an old photo. The mount has changed but you get the idea.

Posted Image

#5 Ed Whitney

Ed Whitney

    Messenger

  • -----
  • Posts: 472
  • Joined: 08 Jul 2010
  • Loc: Palm Coast, Florida

Posted 09 December 2012 - 12:29 PM

Oh Man! Back to square one! I kind of had a feeling the "F60M2" might have had a problem with edge focusing. Geez, I DO appreciate your sharing the info, good and bad.

I had the SV50 in white and it looked and worked, basically "ok", but did think the image was a tad on the dark side. Guesss I'm used to ED glass!

Desertlens, I can hardly follow what you are saying about the UO eyepieces and filters you mention, but will study this a bit more before getting any finder. And, that is ONE sharp looking rig! I'm not grining, just jealous! :)

Tomharri, How DID you figure that out, with swapping lenses! Not bad! I like to tinker, but, oh man!

Almost looks like the Orion 9x50 RACI finder #7020 for $130 might just save the day!

#6 desertlens

desertlens

    Viking 1

  • *****
  • Posts: 825
  • Joined: 06 Dec 2010
  • Loc: 36°N 105°W

Posted 09 December 2012 - 01:15 PM

Ed, My experience was nowhere near as bad as Tomharri's. Much of my problem turned out to be related to widefield EPs. The center was fine but off axis things got pretty bad. The Orthos have a narrower Apparent FoV (40-45°) and this clearly resolved my issues. The True FoV with an 18 is 3.6° and the 25 is 5.2°, still wide by most standards and consistent with the usual finder field. Good luck and have fun.

#7 Ed Whitney

Ed Whitney

    Messenger

  • -----
  • Posts: 472
  • Joined: 08 Jul 2010
  • Loc: Palm Coast, Florida

Posted 09 December 2012 - 06:22 PM

Craig, Yeh, you're right about wide-field and fast scopes. I learned this lesson years ago, they always show blurriness and color fringing. Thanks for helping me decide this. :)

#8 dlapoint

dlapoint

    Viking 1

  • -----
  • Posts: 999
  • Joined: 17 Aug 2003
  • Loc: Moncton NB Canada

Posted 10 December 2012 - 12:22 AM

I find this makes a better telescope than a finder. You can't see the cross hairs and it is real heavy next to a 50mm finder.

#9 Richard Low

Richard Low

    Viking 1

  • *****
  • Posts: 689
  • Joined: 27 Nov 2005
  • Loc: 1 deg N, GMT+8hrs

Posted 10 December 2012 - 01:00 AM

I would like to let you guys know that I have great performance with my SV F60 finder using Pentax XW 14mm; to my eye it is sharp to the edge.

#10 Ed Whitney

Ed Whitney

    Messenger

  • -----
  • Posts: 472
  • Joined: 08 Jul 2010
  • Loc: Palm Coast, Florida

Posted 10 December 2012 - 05:52 PM

Thank You Derek and Richard! I DO appreciate the continued posts.

This is the info I was sort of hopeing for! If I get this scope, I might just be allowed to join the venerable, "60mm Club"! :)

Best to you ALL :)

#11 lamplight

lamplight

    Vanguard

  • *****
  • Posts: 2497
  • Joined: 18 Sep 2012
  • Loc: western MA, U.S.

Posted 10 February 2013 - 10:24 AM

Just came across this. I absolutely love the f60m2. I use it as a finder but also enjoy its views on its own. I never bothered to check the sharpness full field (have only ever used stock EP as felt no need), but I'always appreciate the pinpoint sharpness of e view.. Honestly just haven't looked to the edge of the field with a critical eye. Hmm.. I guess if it was mainly used as a scope i would have of course.. I just got the straight through version for my DOB but haven't used yet.

#12 Pete-LH

Pete-LH

    Messenger

  • *****
  • Posts: 414
  • Joined: 25 Mar 2009
  • Loc: Wilmington, DE

Posted 10 February 2013 - 12:44 PM

Thanks for posting. I've have the 50mm version and wanted to get the 60mm to use with my 5" AP Superplanetary. I've been using a straight through finder but would appreciate the 90 Degree and RACI function at Zenith. I really like the separate x-hair and lens focusing function. I've just held off because of the negatives here and a previous thread. Plus I've been waiting a long time for an answer on a problem I had with on of their x-hair wide field lenses where the reticle fell out.






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics