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RE: [tmboptical] Re: Reducer/Flattener

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  • Terry Tuggle
    Peter, One thing I did not mention is about pixel size; 800mm is the “Sweet Spot” for cameras for 9 micron pixels for best detail. So it really depends on
    Message 1 of 15 , Jan 3, 2010
    • 0 Attachment
      Peter,

      One thing I did not mention is about pixel size; 800mm is the “Sweet
      Spot” for cameras for 9 micron pixels for best detail. So it really depends
      on your camera and what size pixels it has. If it has less than 9 micron
      pixels then a reducer would be a better choice than a FF. Allot of people
      use 500mm or so for the STL’s with 9 micron pixels, but they sacrifice the
      best detail; the images taken with the ST10XME @ 6.8 micron pixels show
      better detail at that focal length.



      All the best,

      Terry



      _____

      From: tmboptical@yahoogroups.com [mailto:tmboptical@yahoogroups.com] On
      Behalf Of pmlogg@...
      Sent: Sunday, November 29, 2009 7:45 PM
      To: tmboptical@yahoogroups.com
      Subject: [tmboptical] Re: Reducer/Flattener





      Terry

      I found your message while seekng options for focal reduction on a TMB
      100/800 CNC. In a reply to an email to Markus he mentioned their own
      flatteners, also shown on the Teton website but they are not reducers. He
      didn't mention the FF2.0, instead suggesting a x.67 from Astrophysics but I
      wondered about A-P's 27TVPH. The former owner of my telescope suggested a TV
      model - the RFL-4087 seems the most appropriate. Then there's the Borg 7887
      x.85, out of production pending replacement by a x.78 unit. I'd wondered
      about the x.8 W.O. TMB designed flattener for the FLT 110 but one owner said
      it would not be compatible.

      Any suggestions would be very welcome.

      Thanks

      Peter Loggie
      Linlithgow, Scotland

      --- In tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com,
      "Terry Tuggle" <tlt284@...> wrote:
      >
      > Frank,
      >
      > Check out Teton Telescopes
      >
      > http://www.tetontel
      <http://www.tetontelescope.com/product_info.php?cPath=47_14_32>
      escope.com/product_info.php?cPath=47_14_32
      > <http://www.tetontel
      <http://www.tetontelescope.com/product_info.php?cPath=47_14_32&products_id=5
      > escope.com/product_info.php?cPath=47_14_32&products_id=5
      > 32> &products_id=532
      >
      > This is a Field Flattener that should work; Mark will know for sure.
      >
      > HTH
      >
      > All the best,
      >
      > Terry
      > _____
      >
      > From: tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com
      [mailto:tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com]
      On
      > Behalf Of Frank Sackenheim GMX
      > Sent: Wednesday, August 12, 2009 8:54 AM
      > To: tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com
      > Subject: [tmboptical] Reducer/Flattener
      >
      > Hi everyone,
      >
      > i am new to this group as i just became a TMB User a couple of weeks
      > ago. I bought a 80/600 TMB in used but perfect condition. As this was
      > my dream telescope for years i was very proud to call it my own. But
      > after the first light with my canon 350d i was disappointed. I used
      > the Tele Vue REF 3007 Reducer for Instruments of 400-800m focal
      > length. The First Light showed very heavy image field curveture in
      > the edges of the image. After some research i found out that i have
      > to increase the backfocus of my setup up to 56mm. i used some spacers
      > to get there and the second light showed some better results as can
      > be seen here: http://frank-
      > <http://frank- <http://frank-sackenheim.de/html/bilder/Crescent_Final.jpg>
      sackenheim.de/html/bilder/Crescent_Final.jpg>
      > sackenheim.de/html/bilder/Crescent_Final.jpg
      > But there is still some image field curvature in the edges, and as > i'm
      going tu use larger chips in the future im searching for a
      > perfectly working reducer for my scope. Its too bad that TMB doesnt
      > build a Reducer/Flattener for this scopes!
      >
      > I Hope someone could help me cause i dont want to change my scope
      > again to a Takahashi Scope:-)
      >
      > CS and Kind Regards Frank
      > _______________________________________
      > Frank Sackenheim
      > Försterstraße 49
      > 50825 Köln
      > Tel 0221 122121
      > Mobil 0163 3122121
      > frank@frank- <mailto:frank%40frank-sackenheim.de> sackenheim.de
      > www.frank-sackenheim.de
      > www.myspace.com/sackenheim
      >





      [Non-text portions of this message have been removed]
    • D Baker
      The nice thing about the Astrophysics 0.75x reducer/corrector is that it is designed to do its job over a field larger than an APS-sized sensor, and the optics
      Message 2 of 15 , Jan 3, 2010
      • 0 Attachment
        The nice thing about the Astrophysics 0.75x reducer/corrector is that it is designed to do its job over a field larger than an APS-sized sensor, and the optics & coatings in it are absolutely first-rate.

        Derek

        ----- Original Message -----
        From: Terry Tuggle
        To: tmboptical@yahoogroups.com
        Sent: Sunday, January 03, 2010 6:26 AM
        Subject: RE: [tmboptical] Re: Reducer/Flattener



        Hi Peter,

        I know most people had success with the TV reducers for the 80mm
        scopes. The new NPR 1073 looks to be a better choice for the 100/800 for
        larger format cameras like the STL's or the DSLR's etc.

        http://www.televue.com/engine/page.asp?ID=169

        HTH,

        All the best,

        Terry

        _____

        From: tmboptical@yahoogroups.com [mailto:tmboptical@yahoogroups.com] On
        Behalf Of pmlogg@...
        Sent: Sunday, November 29, 2009 7:45 PM
        To: tmboptical@yahoogroups.com
        Subject: [tmboptical] Re: Reducer/Flattener

        Terry

        I found your message while seekng options for focal reduction on a TMB
        100/800 CNC. In a reply to an email to Markus he mentioned their own
        flatteners, also shown on the Teton website but they are not reducers. He
        didn't mention the FF2.0, instead suggesting a x.67 from Astrophysics but I
        wondered about A-P's 27TVPH. The former owner of my telescope suggested a TV
        model - the RFL-4087 seems the most appropriate. Then there's the Borg 7887
        x.85, out of production pending replacement by a x.78 unit. I'd wondered
        about the x.8 W.O. TMB designed flattener for the FLT 110 but one owner said
        it would not be compatible.

        Any suggestions would be very welcome.

        Thanks

        Peter Loggie
        Linlithgow, Scotland

        --- In tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com,
        "Terry Tuggle" <tlt284@...> wrote:
        >
        > Frank,
        >
        > Check out Teton Telescopes
        >
        > http://www.tetontel
        <http://www.tetontelescope.com/product_info.php?cPath=47_14_32>
        escope.com/product_info.php?cPath=47_14_32
        > <http://www.tetontel
        <http://www.tetontelescope.com/product_info.php?cPath=47_14_32&products_id=5
        > escope.com/product_info.php?cPath=47_14_32&products_id=5
        > 32> &products_id=532
        >
        > This is a Field Flattener that should work; Mark will know for sure.
        >
        > HTH
        >
        > All the best,
        >
        > Terry
        > _____
        >
        > From: tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com
        [mailto:tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com]
        On
        > Behalf Of Frank Sackenheim GMX
        > Sent: Wednesday, August 12, 2009 8:54 AM
        > To: tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com
        > Subject: [tmboptical] Reducer/Flattener
        >
        > Hi everyone,
        >
        > i am new to this group as i just became a TMB User a couple of weeks
        > ago. I bought a 80/600 TMB in used but perfect condition. As this was
        > my dream telescope for years i was very proud to call it my own. But
        > after the first light with my canon 350d i was disappointed. I used
        > the Tele Vue REF 3007 Reducer for Instruments of 400-800m focal
        > length. The First Light showed very heavy image field curveture in
        > the edges of the image. After some research i found out that i have
        > to increase the backfocus of my setup up to 56mm. i used some spacers
        > to get there and the second light showed some better results as can
        > be seen here: http://frank-
        > <http://frank- <http://frank-sackenheim.de/html/bilder/Crescent_Final.jpg>
        sackenheim.de/html/bilder/Crescent_Final.jpg>
        > sackenheim.de/html/bilder/Crescent_Final.jpg
        > But there is still some image field curvature in the edges, and as > i'm
        going tu use larger chips in the future im searching for a
        > perfectly working reducer for my scope. Its too bad that TMB doesnt
        > build a Reducer/Flattener for this scopes!
        >
        > I Hope someone could help me cause i dont want to change my scope
        > again to a Takahashi Scope:-)
        >
        > CS and Kind Regards Frank
        > _______________________________________
        > Frank Sackenheim
        > Försterstraße 49
        > 50825 Köln
        > Tel 0221 122121
        > Mobil 0163 3122121
        > frank@frank- <mailto:frank%40frank-sackenheim.de> sackenheim.de
        > www.frank-sackenheim.de
        > www.myspace.com/sackenheim
        >

        [Non-text portions of this message have been removed]





        [Non-text portions of this message have been removed]
      • pmlogg@btinternet.com
        Terry Thanks for that advice. It looks as if reducing, with the 100/800 and my CCD is not a good idea. That neatly fits with SBig s advice regarding use of
        Message 3 of 15 , Jan 8, 2010
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          Terry

          Thanks for that advice. It looks as if reducing, with the 100/800 and my CCD is not a good idea. That neatly fits with SBig's advice regarding use of its AO-8 adaptive optics unit (e.g. too far from reducer to imager). I note that TV lists the NPR1073 as a reducer rather than the reducer/flattener, its description for the RFL-1074. Does the NPR1073 flatten as well as the RFL-1074?.

          With my Canon DSLR then I'm uncertain. I've looked at the TS 2" field flattener (not reducer) which seems to have enough back focus for the CCD plus AO-8 and is also claimed to be useable with shorter focal lengths (I have a Tak FS-60C too). I see that it has been discussed as an option to use with the TMB 105mm. It would not of course provide reduction - so back to the TV NPR1073/RFL-4087?

          Thaks

          Peter
        • Terry Tuggle
          Peter, You will have to ask them that specifically, It does not say anything on the website about flattening. Again about the AO8, it is not needed at all for
          Message 4 of 15 , Jan 19, 2010
          • 0 Attachment
            Peter,

            You will have to ask them that specifically, It does not say anything
            on the website about flattening. Again about the AO8, it is not needed at
            all for scopes of these focal lengths. It only becomes useful for scopes
            with a FL of 2000mm or more. (C9.25 and up)



            All the best,

            Terry



            _____

            From: tmboptical@yahoogroups.com [mailto:tmboptical@yahoogroups.com] On
            Behalf Of pmlogg@...
            Sent: Friday, January 08, 2010 11:14 AM
            To: tmboptical@yahoogroups.com
            Subject: [tmboptical] Re: Reducer/Flattener





            Terry

            Thanks for that advice. It looks as if reducing, with the 100/800 and my CCD
            is not a good idea. That neatly fits with SBig's advice regarding use of its
            AO-8 adaptive optics unit (e.g. too far from reducer to imager). I note that
            TV lists the NPR1073 as a reducer rather than the reducer/flattener, its
            description for the RFL-1074. Does the NPR1073 flatten as well as the
            RFL-1074?.

            With my Canon DSLR then I'm uncertain. I've looked at the TS 2" field
            flattener (not reducer) which seems to have enough back focus for the CCD
            plus AO-8 and is also claimed to be useable with shorter focal lengths (I
            have a Tak FS-60C too). I see that it has been discussed as an option to use
            with the TMB 105mm. It would not of course provide reduction - so back to
            the TV NPR1073/RFL-4087?

            Thaks

            Peter





            [Non-text portions of this message have been removed]
          • Terry
            Hi Terry, All I have been using an AT 2 flattener up until now with the QHY8 for use on my TMB 130SS. I will be taking delivery of a Canon 5D Mark II and I am
            Message 5 of 15 , Jan 26, 2010
            • 0 Attachment
              Hi Terry, All

              I have been using an AT 2" flattener up until now with the QHY8 for use on my TMB 130SS. I will be taking delivery of a Canon 5D Mark II and I am quite certain I will need to go for a 2.5" or larger FF.

              I have been coinsidering either the TS Optics 2.5" FF or perhaps the WO 2.5" FF here: http://www.williamoptics.com/accessories/TMBflattener_features.php

              Could you recommend either of the above or any others you know would work for a full frame camera?

              Thanks and clear Skies

              Terry Hancock
              http://www.flickr.com/photos/terryhancock/




              --- In tmboptical@yahoogroups.com, "Terry Tuggle" <tlt284@...> wrote:
              >
              > Peter,
              >
              > You will have to ask them that specifically, It does not say anything
              > on the website about flattening. Again about the AO8, it is not needed at
              > all for scopes of these focal lengths. It only becomes useful for scopes
              > with a FL of 2000mm or more. (C9.25 and up)
              >
              >
              >
              > All the best,
              >
              > Terry
              >
              >
              >
              > _____
              >
              > From: tmboptical@yahoogroups.com [mailto:tmboptical@yahoogroups.com] On
              > Behalf Of pmlogg@...
              > Sent: Friday, January 08, 2010 11:14 AM
              > To: tmboptical@yahoogroups.com
              > Subject: [tmboptical] Re: Reducer/Flattener
              >
              >
              >
              >
              >
              > Terry
              >
              > Thanks for that advice. It looks as if reducing, with the 100/800 and my CCD
              > is not a good idea. That neatly fits with SBig's advice regarding use of its
              > AO-8 adaptive optics unit (e.g. too far from reducer to imager). I note that
              > TV lists the NPR1073 as a reducer rather than the reducer/flattener, its
              > description for the RFL-1074. Does the NPR1073 flatten as well as the
              > RFL-1074?.
              >
              > With my Canon DSLR then I'm uncertain. I've looked at the TS 2" field
              > flattener (not reducer) which seems to have enough back focus for the CCD
              > plus AO-8 and is also claimed to be useable with shorter focal lengths (I
              > have a Tak FS-60C too). I see that it has been discussed as an option to use
              > with the TMB 105mm. It would not of course provide reduction - so back to
              > the TV NPR1073/RFL-4087?
              >
              > Thaks
              >
              > Peter
              >
              >
              >
              >
              >
              > [Non-text portions of this message have been removed]
              >
            • Terry Tuggle
              Terry, I think I would take a wait and see approach. No need of getting something you really do not need; give the 2 inch flattener a whirl and see what
              Message 6 of 15 , May 4 9:20 PM
              • 0 Attachment
                Terry,

                I think I would take a "wait and see" approach. No need of getting
                something you really do not need; give the 2 inch flattener a whirl and see
                what happens!

                HTH,



                All the best,

                Terry



                _____

                From: tmboptical@yahoogroups.com [mailto:tmboptical@yahoogroups.com] On
                Behalf Of Terry
                Sent: Tuesday, January 26, 2010 10:05 AM
                To: tmboptical@yahoogroups.com
                Subject: [tmboptical] Re: Reducer/Flattener





                Hi Terry, All

                I have been using an AT 2" flattener up until now with the QHY8 for use on
                my TMB 130SS. I will be taking delivery of a Canon 5D Mark II and I am quite
                certain I will need to go for a 2.5" or larger FF.

                I have been coinsidering either the TS Optics 2.5" FF or perhaps the WO 2.5"
                FF here: http://www.williamo
                <http://www.williamoptics.com/accessories/TMBflattener_features.php>
                ptics.com/accessories/TMBflattener_features.php

                Could you recommend either of the above or any others you know would work
                for a full frame camera?

                Thanks and clear Skies

                Terry Hancock
                http://www.flickr <http://www.flickr.com/photos/terryhancock/>
                com/photos/terryhancock/

                --- In tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com,
                "Terry Tuggle" <tlt284@...> wrote:
                >
                > Peter,
                >
                > You will have to ask them that specifically, It does not say anything
                > on the website about flattening. Again about the AO8, it is not needed at
                > all for scopes of these focal lengths. It only becomes useful for scopes
                > with a FL of 2000mm or more. (C9.25 and up)
                >
                >
                >
                > All the best,
                >
                > Terry
                >
                >
                >
                > _____
                >
                > From: tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com
                [mailto:tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com]
                On
                > Behalf Of pmlogg@...
                > Sent: Friday, January 08, 2010 11:14 AM
                > To: tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com
                > Subject: [tmboptical] Re: Reducer/Flattener
                >
                >
                >
                >
                >
                > Terry
                >
                > Thanks for that advice. It looks as if reducing, with the 100/800 and my
                CCD
                > is not a good idea. That neatly fits with SBig's advice regarding use of
                its
                > AO-8 adaptive optics unit (e.g. too far from reducer to imager). I note
                that
                > TV lists the NPR1073 as a reducer rather than the reducer/flattener, its
                > description for the RFL-1074. Does the NPR1073 flatten as well as the
                > RFL-1074?.
                >
                > With my Canon DSLR then I'm uncertain. I've looked at the TS 2" field
                > flattener (not reducer) which seems to have enough back focus for the CCD
                > plus AO-8 and is also claimed to be useable with shorter focal lengths (I
                > have a Tak FS-60C too). I see that it has been discussed as an option to
                use
                > with the TMB 105mm. It would not of course provide reduction - so back to
                > the TV NPR1073/RFL-4087?
                >
                > Thaks
                >
                > Peter
                >
                >
                >
                >
                >
                > [Non-text portions of this message have been removed]
                >





                [Non-text portions of this message have been removed]
              • Terry Hancock
                Hi Terry Thanks for the response, I wrote that email in January..LOL, not your fault but I guess if I am not mistaken this group has been down since January
                Message 7 of 15 , May 5 9:50 AM
                • 0 Attachment
                  Hi Terry

                  Thanks for the response, I wrote that email in January..LOL, not your fault
                  but I guess if I am not mistaken this group has been down since January 20th
                  for some reason?. Anyhow I did take your advice (without knowing your
                  answer) the AT 2" FF works great except close to the edges of the field
                  where there is significant vignetting but by adding flats this is easily
                  cancelled out. This is the only image I have so far
                  http://www.flickr.com/photos/terryhancock/4445984428/ and I didn't add flats
                  or darks!!, I was very happy with the results.



                  I have been playing around with an ATRC8 for the past couple of months, just
                  put the TMB 130 back on the mount yesterday. I am hoping to shoot M31 soon,
                  I will keep you posted.



                  All the best and Clear Skies

                  Terry Hancock

                  http://www.downunderobservatory.com/

                  http://www.flickr.com/photos/terryhancock/







                  From: tmboptical@yahoogroups.com [mailto:tmboptical@yahoogroups.com] On
                  Behalf Of Terry Tuggle
                  Sent: Wednesday, May 05, 2010 12:21 AM
                  To: tmboptical@yahoogroups.com
                  Subject: RE: [tmboptical] Re: Reducer/Flattener





                  Terry,

                  I think I would take a "wait and see" approach. No need of getting
                  something you really do not need; give the 2 inch flattener a whirl and see
                  what happens!

                  HTH,

                  All the best,

                  Terry

                  _____

                  From: tmboptical@yahoogroups.com <mailto:tmboptical%40yahoogroups.com>
                  [mailto:tmboptical@yahoogroups.com <mailto:tmboptical%40yahoogroups.com> ]
                  On
                  Behalf Of Terry
                  Sent: Tuesday, January 26, 2010 10:05 AM
                  To: tmboptical@yahoogroups.com <mailto:tmboptical%40yahoogroups.com>
                  Subject: [tmboptical] Re: Reducer/Flattener

                  Hi Terry, All

                  I have been using an AT 2" flattener up until now with the QHY8 for use on
                  my TMB 130SS. I will be taking delivery of a Canon 5D Mark II and I am quite
                  certain I will need to go for a 2.5" or larger FF.

                  I have been coinsidering either the TS Optics 2.5" FF or perhaps the WO 2.5"
                  FF here: http://www.williamo
                  <http://www.williamoptics.com/accessories/TMBflattener_features.php>
                  ptics.com/accessories/TMBflattener_features.php

                  Could you recommend either of the above or any others you know would work
                  for a full frame camera?

                  Thanks and clear Skies

                  Terry Hancock
                  http://www.flickr <http://www.flickr.com/photos/terryhancock/>
                  com/photos/terryhancock/

                  --- In tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com,
                  "Terry Tuggle" <tlt284@...> wrote:
                  >
                  > Peter,
                  >
                  > You will have to ask them that specifically, It does not say anything
                  > on the website about flattening. Again about the AO8, it is not needed at
                  > all for scopes of these focal lengths. It only becomes useful for scopes
                  > with a FL of 2000mm or more. (C9.25 and up)
                  >
                  >
                  >
                  > All the best,
                  >
                  > Terry
                  >
                  >
                  >
                  > _____
                  >
                  > From: tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com
                  [mailto:tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com]
                  On
                  > Behalf Of pmlogg@...
                  > Sent: Friday, January 08, 2010 11:14 AM
                  > To: tmboptical@yahoogro <mailto:tmboptical%40yahoogroups.com> ups.com
                  > Subject: [tmboptical] Re: Reducer/Flattener
                  >
                  >
                  >
                  >
                  >
                  > Terry
                  >
                  > Thanks for that advice. It looks as if reducing, with the 100/800 and my
                  CCD
                  > is not a good idea. That neatly fits with SBig's advice regarding use of
                  its
                  > AO-8 adaptive optics unit (e.g. too far from reducer to imager). I note
                  that
                  > TV lists the NPR1073 as a reducer rather than the reducer/flattener, its
                  > description for the RFL-1074. Does the NPR1073 flatten as well as the
                  > RFL-1074?.
                  >
                  > With my Canon DSLR then I'm uncertain. I've looked at the TS 2" field
                  > flattener (not reducer) which seems to have enough back focus for the CCD
                  > plus AO-8 and is also claimed to be useable with shorter focal lengths (I
                  > have a Tak FS-60C too). I see that it has been discussed as an option to
                  use
                  > with the TMB 105mm. It would not of course provide reduction - so back to
                  > the TV NPR1073/RFL-4087?
                  >
                  > Thaks
                  >
                  > Peter
                  >
                  >
                  >
                  >
                  >
                  > [Non-text portions of this message have been removed]
                  >

                  [Non-text portions of this message have been removed]





                  [Non-text portions of this message have been removed]
                • galaxyscientific
                  Dear Frank, I am using 80/600 also, and test against these flattener / reducers with my Canon 5D Mark II (full frame) - TS optics 2 flattener - TS optics 2.5
                  Message 8 of 15 , Jun 11, 2010
                  • 0 Attachment
                    Dear Frank,

                    I am using 80/600 also, and test against these flattener / reducers with my Canon 5D Mark II (full frame)

                    - TS optics 2" flattener
                    - TS optics 2.5" flattener
                    - BORG 7887 0.85x reducer / flattener
                    - Sky Watcher ED80 0.85x reducer / flattener
                    - Televue 0.8x reducer / flattener

                    of the above, the TS optics 2" flattener is the best corrected one with stars sharp to the corner. Then for reducer / flattener, the Sky Watchter one is much better than the other 2.

                    The I modify the camera connection from typical T Ring (42mm P0.75) to 48mm version, and the light drop at the corner improve a lot.

                    Regards,
                    Savio Fong
                    Galaxy Scientific Group
                    Hong Kong

                    --- In tmboptical@yahoogroups.com, Frank Sackenheim GMX <frank.sackenheim@...> wrote:
                    >
                    > Hi everyone,
                    >
                    > i am new to this group as i just became a TMB User a couple of weeks
                    > ago. I bought a 80/600 TMB in used but perfect condition. As this was
                    > my dream telescope for years i was very proud to call it my own. But
                    > after the first light with my canon 350d i was disappointed. I used
                    > the Tele Vue REF 3007 Reducer for Instruments of 400-800m focal
                    > length. The First Light showed very heavy image field curveture in
                    > the edges of the image. After some research i found out that i have
                    > to increase the backfocus of my setup up to 56mm. i used some spacers
                    > to get there and the second light showed some better results as can
                    > be seen here: http://frank-sackenheim.de/html/bilder/Crescent_Final.jpg
                    > But there is still some image field curvature in the edges, and as i
                    > ´m going tu use larger chips in the future im searching for a
                    > perfectly working reducer for my scope. Its too bad that TMB doesnt
                    > build a Reducer/Flattener for this scopes!
                    >
                    > I Hope someone could help me cause i dont want to change my scope
                    > again to a Takahashi Scope:-)
                    >
                    > CS and Kind Regards Frank
                    >
                    > _______________________________________
                    > Frank Sackenheim
                    > Försterstraße 49
                    > 50825 Köln
                    > Tel 0221 122121
                    > Mobil 0163 3122121
                    > frank@...
                    > www.frank-sackenheim.de
                    > www.myspace.com/sackenheim
                    >
                    >
                    >
                    >
                    >
                    > [Non-text portions of this message have been removed]
                    >
                  • Frank Sackenheim GMX
                    Hi Savio meanwhile Markus Ludes told me to try the Skywatcer 0.85. Well after a first test i think its the best result i´ver ever got. I will test it again as
                    Message 9 of 15 , Jun 12, 2010
                    • 0 Attachment
                      Hi Savio

                      meanwhile Markus Ludes told me to try the Skywatcer 0.85. Well after a
                      first test i think its the best result i�ver ever got. I will test it
                      again as soon as the weather conditions allow to do so. But i think
                      full frame is the largest chip, i dont believe it would fit with a
                      11000 chip.

                      I cant really follow you about the modification, you did what? And how
                      did it aprove your pictures?

                      Cheers Frank


                      Am 12.06.2010 um 05:13 schrieb galaxyscientific:

                      > Dear Frank,
                      >
                      > I am using 80/600 also, and test against these flattener / reducers
                      > with my Canon 5D Mark II (full frame)
                      >
                      > - TS optics 2" flattener
                      > - TS optics 2.5" flattener
                      > - BORG 7887 0.85x reducer / flattener
                      > - Sky Watcher ED80 0.85x reducer / flattener
                      > - Televue 0.8x reducer / flattener
                      >
                      > of the above, the TS optics 2" flattener is the best corrected one
                      > with stars sharp to the corner. Then for reducer / flattener, the
                      > Sky Watchter one is much better than the other 2.
                      >
                      > The I modify the camera connection from typical T Ring (42mm P0.75)
                      > to 48mm version, and the light drop at the corner improve a lot.
                      >
                      > Regards,
                      > Savio Fong
                      > Galaxy Scientific Group
                      > Hong Kong
                      >
                      > --- In tmboptical@yahoogroups.com, Frank Sackenheim GMX
                      > <frank.sackenheim@...> wrote:
                      > >
                      > > Hi everyone,
                      > >
                      > > i am new to this group as i just became a TMB User a couple of weeks
                      > > ago. I bought a 80/600 TMB in used but perfect condition. As this
                      > was
                      > > my dream telescope for years i was very proud to call it my own. But
                      > > after the first light with my canon 350d i was disappointed. I used
                      > > the Tele Vue REF 3007 Reducer for Instruments of 400-800m focal
                      > > length. The First Light showed very heavy image field curveture in
                      > > the edges of the image. After some research i found out that i have
                      > > to increase the backfocus of my setup up to 56mm. i used some
                      > spacers
                      > > to get there and the second light showed some better results as can
                      > > be seen here: http://frank-sackenheim.de/html/bilder/Crescent_Final.jpg
                      > > But there is still some image field curvature in the edges, and as i
                      > > �m going tu use larger chips in the future im searching for a
                      > > perfectly working reducer for my scope. Its too bad that TMB doesnt
                      > > build a Reducer/Flattener for this scopes!
                      > >
                      > > I Hope someone could help me cause i dont want to change my scope
                      > > again to a Takahashi Scope:-)
                      > >
                      > > CS and Kind Regards Frank
                      > >
                      > > _______________________________________
                      > > Frank Sackenheim
                      > > F�rsterstra�e 49
                      > > 50825 K�ln
                      > > Tel 0221 122121
                      > > Mobil 0163 3122121
                      > > frank@...
                      > > www.frank-sackenheim.de
                      > > www.myspace.com/sackenheim
                      > >
                      > >
                      > >
                      > >
                      > >
                      > > [Non-text portions of this message have been removed]
                      > >
                      >
                      >

                      _______________________________________
                      Frank Sackenheim
                      F�rsterstra�e 49
                      50825 K�ln
                      Tel 0221 122121
                      Mobil 0163 3122121
                      frank@...
                      www.frank-sackenheim.de
                      www.myspace.com/sackenheim





                      [Non-text portions of this message have been removed]
                    • Savio Fong
                      Dear Frank, this is how we do indoor test (the thread show how we test a Sky Watcher Equinox 80), the merit of Sky Watcher is the camera connect is M48, bigger
                      Message 10 of 15 , Jun 14, 2010
                      • 0 Attachment
                        Dear Frank,


                        this is how we do indoor test (the thread show how we test a Sky Watcher
                        Equinox 80), the merit of Sky Watcher is the camera connect is M48,
                        bigger than T2 and improve vignetting, my own corridor is longer than
                        here, at 25m there may be tiny bit of spherical abberation left, but
                        usually a good indicator of the performance under real sky test, i.e.,
                        if it perform poor under indoor test, we don't test it under real sky,
                        if it perform good then usually the real sky test won't be bad.

                        I made a custom adaptor to connect the flattener to a Borg 2" tube,
                        http://www.astrocafe.hk/viewtopic.php?f=21&t=243&p=1785&hilit=skywatcher+0.85x#p1785

                        This is a real setup of my APM-LOMO 80/600 with TS2 zero power
                        flattener, I used a Sky Watcher 48mm camera connect to minimize the
                        vignetting, at 100% crop of centre and 4 corners, all stars are sharp to
                        the corner of Canon 5D Mark II with 135 full frame and 6.4um pixel, so
                        you expect it 40% sharper with 9um pixel from STL11000M.

                        http://www.astrocafe.hk/viewtopic.php?f=18&t=333

                        Only the lower left is a bit off focus due to my poor adaptor made, now fixed.

                        this is a earlier NGC7000 made under very poor transparency sky, the vignetting is noticeable using M42 T ring, now much improved with M48 camera connect.
                        http://www.astrocafe.hk/viewtopic.php?f=17&t=302&p=2595&hilit=NGC7000#p2595

                        a side discussion, this is my Jupiter through my own APM-TMB 203 APO, you can see the transit of Ganymede with surface mark visible.
                        http://www.astrocafe.hk/viewtopic.php?f=16&t=43

                        regards,
                        Savio
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