Loading ...
Sorry, an error occurred while loading the content.

Re: Evaluating my "new" Megrez

Expand Messages
  • no_names_remain99
    Gordon- Check the previous posts I made regarding star tests with my Megrez II. Another gentleman and others have discussed their star test images. There have
    Message 1 of 8 , Oct 1, 2004
    • 0 Attachment
      Gordon-

      Check the previous posts I made regarding star tests with my Megrez
      II. Another gentleman and others have discussed their star test
      images. There have been issues with test images, some worse then
      others. I recieved one of the "lucky" ones and have had to send mine
      back in August and I await lens replacement.

      -Chris


      --- In William-Optics@yahoogroups.com, "gordogower2000" <ggower@t...>
      wrote:
      > I spent some time doing some casual star gazing tonight with
      my "new"
      > Megrez with its brand new WO diagonal.
      >
      > I find that star images inside of focus have a decent set of rings,
      > but outside of focus, star images are just blobs of light. Can
      > someone tell me what that means?
      >
      > I should add that a former owner has placed a tinfoil spacer
      between
      > the lens elements apparently to relieve some astigmatism (so I was
      > told by the prev. owner,and I can see the tinfoil).
      >
      > I am not a star test expert. Can someone advise?
      >
      > Thanks,
      >
      > Gordon Gower
      > Tucson
    • gordogower2000
      ... Megrez ... mine ... Is there a place I can send my older Megrez (Anacortes, WO ??) to have the optics professionally checked? I know they have had an
      Message 2 of 8 , Oct 1, 2004
      • 0 Attachment
        --- In William-Optics@yahoogroups.com, no_names_remain99
        <no_reply@y...> wrote:
        > Gordon-
        >
        > Check the previous posts I made regarding star tests with my
        Megrez
        > II. Another gentleman and others have discussed their star test
        > images. There have been issues with test images, some worse then
        > others. I recieved one of the "lucky" ones and have had to send
        mine
        > back in August and I await lens replacement.
        >
        > -Chris

        Is there a place I can send my older Megrez (Anacortes, WO ??) to
        have the optics professionally checked? I know they have had an
        amateur adjustment for astigmatism, and I am wondering about other
        problems,since I have such a strange star test.

        Thanks,

        Gordon G
      • gary
        Does the Megrez ship with enough spaces so you can not use a diagonal? If so, give it a shot. Your viewing position will be awkward and the image upside down,
        Message 3 of 8 , Oct 1, 2004
        • 0 Attachment
          Does the Megrez ship with enough spaces so you can not use a diagonal?
          If so, give it a shot. Your viewing position will be awkward and the
          image upside down, but it does take one error source (the diagonal) out
          of the equation.

          gordogower2000 wrote:

          > --- In William-Optics@yahoogroups.com, no_names_remain99
          > <no_reply@y...> wrote:
          >
          >>Gordon-
          >>
          >> Check the previous posts I made regarding star tests with my
          >
          > Megrez
          >
          >>II. Another gentleman and others have discussed their star test
          >>images. There have been issues with test images, some worse then
          >>others. I recieved one of the "lucky" ones and have had to send
          >
          > mine
          >
          >>back in August and I await lens replacement.
          >>
          >>-Chris
          >
          >
          > Is there a place I can send my older Megrez (Anacortes, WO ??) to
          > have the optics professionally checked? I know they have had an
          > amateur adjustment for astigmatism, and I am wondering about other
          > problems,since I have such a strange star test.
          >
          > Thanks,
          >
          > Gordon G
          >
          >
          >
          >
          >
          > Yahoo! Groups Links
          >
          >
          >
          >
          >
          >
          >
          >
          >
        • spacephotographer
          Gordon: Is your star test similar to what I posted in the photo section? Look in Ignacio Alberto folder ( There is another Ignacio ) I still don´t know how
          Message 4 of 8 , Oct 1, 2004
          • 0 Attachment
            Gordon:

            Is your star test similar to what I posted in the photo section?

            Look in Ignacio Alberto folder ( There is another Ignacio )

            I still don´t know how bad is my problem but I think you should
            perform some real tests like observing the moon or saturn. If the
            views are fine then you dont have a problem. You have to compare the
            view with a similar telescope. ( 70 to 90mm ) Don´t try to compare to
            a larger telescope because the performance would not be better even
            with perfect optics.

            Having diffraction rings in only one side of focus is a clear symptom
            of spherical aberration, however all refractors have this problem to
            some extent. If the error is really bad ( 1 wave or more ) you won´t
            be able to focus on saturn or have 100X-120X on the moon.

            If it is 0.2 to 0.3 wave error you also have the bad star test but
            the optics are still in the acceptable region and is very difficult
            to see any difference.



            Ignacio







            --- In William-Optics@yahoogroups.com, "gordogower2000" <ggower@t...>
            wrote:
            > I spent some time doing some casual star gazing tonight with
            my "new"
            > Megrez with its brand new WO diagonal.
            >
            > I find that star images inside of focus have a decent set of rings,
            > but outside of focus, star images are just blobs of light. Can
            > someone tell me what that means?
            >
            > I should add that a former owner has placed a tinfoil spacer
            between
            > the lens elements apparently to relieve some astigmatism (so I was
            > told by the prev. owner,and I can see the tinfoil).
            >
            > I am not a star test expert. Can someone advise?
            >
            > Thanks,
            >
            > Gordon Gower
            > Tucson
          • gordogower2000
            ... the ... to ... symptom ... to ... won´t ... Yes, my star test is very similar to yours: rings inside of focus and a big white blob outside of focus. I
            Message 5 of 8 , Oct 2, 2004
            • 0 Attachment
              --- In William-Optics@yahoogroups.com, "spacephotographer"
              <igrodroch@a...> wrote:
              > Gordon:
              >
              > Is your star test similar to what I posted in the photo section?
              >
              > Look in Ignacio Alberto folder ( There is another Ignacio )
              >
              > I still don´t know how bad is my problem but I think you should
              > perform some real tests like observing the moon or saturn. If the
              > views are fine then you dont have a problem. You have to compare
              the
              > view with a similar telescope. ( 70 to 90mm ) Don´t try to compare
              to
              > a larger telescope because the performance would not be better even
              > with perfect optics.
              >
              > Having diffraction rings in only one side of focus is a clear
              symptom
              > of spherical aberration, however all refractors have this problem
              to
              > some extent. If the error is really bad ( 1 wave or more ) you
              won´t
              > be able to focus on saturn or have 100X-120X on the moon.
              >
              > If it is 0.2 to 0.3 wave error you also have the bad star test but
              > the optics are still in the acceptable region and is very difficult
              > to see any difference.
              >

              Yes, my star test is very similar to yours: rings inside of focus and
              a big white blob outside of focus. I have not tried high mag. as I
              have a 12.5 newt for that kind of observing.

              Now, what can be done about this? Will WO or Anacortes replace a
              lens that is bad enough? Can they tweek it somehow? Since my scope
              is not new, it is not a warranty issue. I am just wondering how to
              fix what's broke!

              GG
            • doug92562
              Send an email to William Optics explaining the problem, you will find William himself very helpful. I doubt you will be able to get a warranty replacement,
              Message 6 of 8 , Oct 2, 2004
              • 0 Attachment
                Send an email to William Optics explaining the problem, you will find
                William himself very helpful. I doubt you will be able to get a
                warranty replacement, especially if someone modified the lens. The
                new ED triplet is available as a separate purchase by the way, I am
                awaiting mine. Screws right in where the original doublet did, uses
                same dew cap. The list price is 350, you may be able to get it
                cheaper. Color correction is claimed 5x better than the doublet.
              • gordogower2000
                ... find ... Thanks, Doug. I will give this a try. Gordon G
                Message 7 of 8 , Oct 3, 2004
                • 0 Attachment
                  --- In William-Optics@yahoogroups.com, "doug92562"
                  <dougspeterson@m...> wrote:
                  >
                  > Send an email to William Optics explaining the problem, you will
                  find
                  > William himself very helpful. I doubt you will be able to get a
                  > warranty replacement, especially if someone modified the lens. The
                  > new ED triplet is available as a separate purchase by the way, I am
                  > awaiting mine. Screws right in where the original doublet did, uses
                  > same dew cap. The list price is 350, you may be able to get it
                  > cheaper. Color correction is claimed 5x better than the doublet.

                  Thanks, Doug.

                  I will give this a try.

                  Gordon G
                Your message has been successfully submitted and would be delivered to recipients shortly.