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Re: TMB 203mm F/7 and 130mm F/9,23 vs. AP 130mm F/f8.35 APO Tests

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  • tmboptical
    ... how ... Hi Tim, Yes, it is the best test of all. ... It does work on the AP 900 GTO, and this is a truly portable 8 apo setup. For people without an
    Message 1 of 22 , Jul 3, 2005
      --- In tmboptical@yahoogroups.com, "Tube Tim" <potentate@s...> wrote:
      > >--- In tmboptical@yahoogroups.com, "tmboptical" <TMBoptical@a...
      > > wrote:
      > > Hello All!
      > >
      > > The first (serial number 001) TMB 203mm f/7 SD apochromat is
      > > here at TMB Optical, and I have run the autocollimation tests
      > > on the lens. Also tested was the new TMB all out planetary
      > > 130mm f/9.23 SD triplet apo lens.
      >
      > > <snip>
      >
      > This is some great news on the 4'th of July holiday; you sure know
      how
      > it's done.
      >
      > The 203-f/7 sounds like a great lens and will be good excellent for
      > visual as well as photographic use. A little colour out of focus on
      > the double pass is nothing whereas no color at focus on the double
      > pass is really says it all. That's the best test of all.

      Hi Tim,

      Yes, it is the best test of all.

      > This shorter tube means a Parallax HD-150C GEM would handle it
      > easily and perhaps an AP-900 GEM. That's a big plus.

      It does work on the AP 900 GTO, and this is a truly portable 8"
      apo setup. For people without an observatory, or want to take
      the scope to star parties or dark sites, this is the ultimate
      one man apo refractor. And for small observatories, it can
      be the perfect telescope.


      > The 130-f/9.23 sounds like a lens that will go down in the history
      > books as a planetary classic.
      >
      > Congratulations to you for the design and Markus and LZOS for
      bringing
      > these to the amateur market. TMB Optical has so many refractors
      > available now it's mind numbing.

      Thanks. The 130 f/9.23 won't sell like hotcakes, but the people
      that own it, will never be disappointed in its views. We do have
      a lot of refractors on the market, don't we? :-)

      > I hope you get some nice Wx, especially for tomorrow's night
      fireworks
      > show. I suspect the actual star test will do well, given the double
      > pass results.

      We have been getting thunderstorms, and when it clears, bad seeing.
      But the weather is changing, so there is hope for a good night to
      test all the telescopes.

      > > Next post -- The New TMB/Burgess wide angle long eye relief
      > > Planetary eyepieces. I have just tested the 4mm, and wow!
      > > Pictures and a full review coming.
      >
      > 4mm wide field, WOW is right. I can't wait.
      > ___
      > Tim

      Yes, I will have a review and possibly a photo of the new
      4mm up today. Look out for it.

      Thomas Back
    • tmboptical
      ... Hi Harvey, I am too, I need to test these babies, if I am going to send them out. It s great to hear that you are so excited, so am I. Any chance you will
      Message 2 of 22 , Jul 3, 2005
        --- In tmboptical@yahoogroups.com, "mrgrytt" <mrgrytt@i...> wrote:
        > --- In tmboptical@yahoogroups.com, "tmboptical" <TMBoptical@a...>
        wrote:
        > > Hello All!
        > >
        > > The first (serial number 001) TMB 203mm f/7 SD apochromat is
        > > here at TMB Optical, and I have run the autocollimation tests
        > > on the lens. Also tested was the new TMB all out planetary
        > > 130mm f/9.23 SD triplet apo lens.
        > >
        > > In conclusion, how good are the TMB 130mm f/9.23 optics?
        > > As good I have ever tested, with the exception of the above
        > > telescopes. I feel the 130mm f/9.23 SD apochromat is the best
        > > 5" planetary telescope ever offer as a production telescope.
        > > We will see if my customers that receive the TMB 8" f/7 and
        > > 130mm f/9.23 agree with what I have to say.
        >
        > Thomas,
        > I'm praying hard for you to have clear skies. I can't remember
        > being this excited about anything....... except maybe the TMB 175.
        >
        > Harvey

        Hi Harvey,

        I am too, I need to test these babies, if I am going to send them
        out. It's great to hear that you are so excited, so am I. Any
        chance you will bring it to the BFSP?

        Thomas Back
      • tmboptical
        ... Hi Jim, Thanks for the kind words about our new 130mm. The 130mm f/6 is all that you say it is. The choice comes down to a rather simple one. Is that last
        Message 3 of 22 , Jul 3, 2005
          --- In tmboptical@yahoogroups.com, "jimhp29401us" <thefamily90@h...>
          wrote:
          > I agree Tim. This sounds Great! I purchased a 130 F/6 which is a
          > beautiful compact scope but now I am second guessing. That F/9.23
          > sounds fantastic.
          > Congratulations Tom, Markus and LZOS! LKooking forward to hearing
          > more.
          >
          > Jim Phillips

          Hi Jim,

          Thanks for the kind words about our new 130mm. The 130mm f/6 is all
          that you say it is. The choice comes down to a rather simple one.
          Is that last bit of contrast on the moon and planets, worth the
          longer tube length, and maybe a bigger mount?

          I think most people know which one I am going to get. But the f/6
          is more versatile, and you can't beat it for its size. And I will
          have more to say about it, once I get one good seeing night.

          Thomas Back
        • tmboptical
          ... Hi Clark, ... Thank you. ... Markus did test for this, and he found that the f/7 does take a bit longer to cool down. That is totally expected, because as
          Message 4 of 22 , Jul 3, 2005
            --- In tmboptical@yahoogroups.com, "huskercr" <huskercr@i...> wrote:
            > Thomas -

            Hi Clark,

            > Certainly sounds as if you have a couple of winners on your hands!
            > Congratulations.

            Thank you.

            > Do the sharp curves needed to make a 203 f7 imply thick glass and
            > therefore noticeable cooldown times?

            Markus did test for this, and he found that the f/7 does take a bit
            longer to cool down. That is totally expected, because as you say,
            the glass has more mass, and the steeper curves. But, as I have been
            saying for 15 years now, if you slide or take off your dew shield,
            and let the lens cool down faster, and then when it hits null, you
            put the dew shield back on, you can speed up cool down a lot. Even
            my AP 180mm f/9 EDT with its dew shield in place takes a long time
            to cool down, and Alan French takes his dew shield off of his 8"
            AP, and he says that it helps cool-down.

            > As for the LE eyepieces, who will be distributing them? Who can I
            > contact to find out what focal lengths will be available and to be
            > placed on the waitlist?

            Just for your information, the 4mm planetary eyepiece I was talking
            about is not the LE's, but to answer your question, we are having
            a delay on the LE's, so if you want to be on the wait-list, just
            e-mail me. It looks like we will have a 3.5mm, 5mm, 8mm, 10mm, 13mm,
            and 17mm, with a possible 21mm. The new wide angle planetary
            eyepieces are finished in three focal lengths (there will be more),
            and have passed my tests, beyond my expectations.

            > Again, congrats on moving the standards for large APOs even higher.

            I really appreciate that.

            Thomas Back
          • tmboptical
            ... Thanks Mike. Thomas Back
            Message 5 of 22 , Jul 3, 2005
              --- In tmboptical@yahoogroups.com, "Mike C" <mike@e...> wrote:
              > Congratulation Thomas on your much deserved results.
              >
              > Mike

              Thanks Mike.

              Thomas Back
            • Wayne G
              ... From: tmboptical@yahoogroups.com [mailto:tmboptical@yahoogroups.com]On Behalf Of tmboptical Sent: Saturday, July 02, 2005 5:46 PM To:
              Message 6 of 22 , Jul 3, 2005
                -----Original Message-----
                From: tmboptical@yahoogroups.com [mailto:tmboptical@yahoogroups.com]On
                Behalf Of tmboptical
                Sent: Saturday, July 02, 2005 5:46 PM
                To: tmboptical@yahoogroups.com
                Subject: [tmboptical] TMB 203mm F/7 and 130mm F/9,23 vs. AP 130mm F/f8.35
                APO Tests



                Hello All!

                The first (serial number 001) TMB 203mm f/7 SD apochromat is
                here at TMB Optical, and I have run the autocollimation tests
                on the lens. Also tested was the new TMB all out planetary
                130mm f/9.23 SD triplet apo lens.


                WG: Wow, Tom! What a riveting report! I am thrilled for you! Have a VERY
                happy Fourth.

                Wayne
              • mrgrytt
                ... Hi Thomas, I will most certainly bring it to the BFSP. I ll surely have the scope finished by then. Harvey
                Message 7 of 22 , Jul 3, 2005
                  --- In tmboptical@yahoogroups.com, "tmboptical" <TMBoptical@a...> wrote:
                  > >
                  > > Thomas,
                  > > I'm praying hard for you to have clear skies. I can't remember
                  > > being this excited about anything....... except maybe the TMB 175.
                  > >
                  > > Harvey
                  >
                  > Hi Harvey,
                  >
                  > I am too, I need to test these babies, if I am going to send them
                  > out. It's great to hear that you are so excited, so am I. Any
                  > chance you will bring it to the BFSP?
                  >
                  > Thomas Back

                  Hi Thomas,
                  I will most certainly bring it to the BFSP. I'll surely have the
                  scope finished by then.

                  Harvey
                • Terry L Tuggle
                  Jim, As Tom has said many times, the difference can only be seen during periods of excellent seeing conditions. As Tim has pointed out the f/6 has it all. If
                  Message 8 of 22 , Jul 3, 2005
                    Jim,

                    As Tom has said many times, the difference can only be seen during
                    periods of excellent seeing conditions. As Tim has pointed out the f/6 has
                    it all. If you were needing a scope for one purpose...planetary observing,
                    the f/9.23 would be the better choice. While it would not make allot of
                    difference in CCD imaging, for film work, the f/6 has the best advantage.

                    Terry



                    _____

                    From: tmboptical@yahoogroups.com [mailto:tmboptical@yahoogroups.com] On
                    Behalf Of Tube Tim
                    Sent: Sunday, July 03, 2005 10:58 AM
                    To: tmboptical@yahoogroups.com
                    Subject: [tmboptical] Re: TMB 203mm F/7 and 130mm F/9,23 vs. AP 130mm
                    F/f8.35 APO Tests



                    >--- In tmboptical@yahoogroups.com, "jimhp29401us" <thefamily90@h...
                    > wrote:
                    > I agree Tim. This sounds Great! I purchased a 130 F/6 which is a
                    > beautiful compact scope but now I am second guessing. That F/9.23
                    > sounds fantastic.

                    From Markus post of the 130 f/6 a while back, it's a beautiful scope,
                    well executed. That's an ideal scope for taking out to remote sites
                    for imaging as well as staying near home and planetary / lunar /
                    double observing.

                    > Congratulations Tom, Markus and LZOS! LKooking forward to hearing
                    > more.
                    >
                    > Jim Phillips
                    >

                    ___
                    Tim






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                    [Non-text portions of this message have been removed]
                  • mrgrytt
                    Terry, There are several advantages to a slower f/ratio. Of course whether you consider some things to be an advantage or not all depends on what you want
                    Message 9 of 22 , Jul 3, 2005
                      Terry,
                      There are several advantages to a slower f/ratio. Of course
                      whether you consider some things to be an advantage or not all depends
                      on what you want from the scope.
                      For visual use it is an easy choice to make, at least for me.
                      This is without even considering the optical advantage it may have
                      under optimum seeing conditions.
                      You have a flatter field, less sensitive focusing due to greater
                      depth of field, and most eyepiece designs work well. In addition, if
                      a heavier scope weight forces you into a mount with greater capacity I
                      consider that to be a "good thing".
                      For photography you may have to expose a little longer to go as
                      deep, but it's certainly something you can do. If the photographic
                      speed is a big issue you can stick a .75x telecompressor in the system
                      and quickly have a f/6.9 scope. That is certainly fast enough to make
                      me happy.
                      At the risk of mentioning a competitor, a guy named Roland takes
                      some pretty good pictures with a f/14.6 scope, so the f/ratio can't be
                      an "end all" for photography.
                      If you prefer a smaller package, and/or a faster f/ratio, the f/6
                      is the way to go for sure, but you will be giving up some performance
                      in some areas. It's physically impossible not to.
                      Everything in optics is a tradeoff. Whatever you do to gain in
                      one area will cause you to loose in another.
                      It is very fortunate for us that there are people designing
                      equipment that gives us fantastic performance in all areas, regardless
                      of which particular strengths we insist are included in our particular
                      scopes.

                      Harvey

                      -- In tmboptical@yahoogroups.com, "Terry L Tuggle" <tlt284@v...> wrote:
                      > Jim,
                      >
                      > As Tom has said many times, the difference can only be seen during
                      > periods of excellent seeing conditions. As Tim has pointed out the
                      > f/6 has it all. If you were needing a scope for one purpose
                      > ...planetary observing, the f/9.23 would be the better choice.
                      > While it would not make al lot of difference in CCD imaging, for
                      > film work, the f/6 has the best advantage.
                      >
                      > Terry
                      >
                      > >--- In tmboptical@yahoogroups.com, "jimhp29401us" <thefamily90@h...
                      > > wrote:
                      > > I agree Tim. This sounds Great! I purchased a 130 F/6 which is a
                      > > beautiful compact scope but now I am second guessing. That F/9.23
                      > > sounds fantastic.
                      > >
                      > > Jim Phillips
                    • jimhp29401us
                      Hey, when is the BFSP this year? Thanks! Jim Phillips ... the
                      Message 10 of 22 , Jul 3, 2005
                        Hey, when is the BFSP this year?

                        Thanks!

                        Jim Phillips


                        > > I am too, I need to test these babies, if I am going to send them
                        > > out. It's great to hear that you are so excited, so am I. Any
                        > > chance you will bring it to the BFSP?
                        > >
                        > > Thomas Back
                        >
                        > Hi Thomas,
                        > I will most certainly bring it to the BFSP. I'll surely have
                        the
                        > scope finished by then.
                        >
                        > Harvey
                      • mrgrytt
                        ... Jim, Here is the info. http://www.bfsp.org/starparty/index.cfm?CFID=321248&CFTOKEN=54142091 I received an e-mail about 5 days ago saying that there were
                        Message 11 of 22 , Jul 3, 2005
                          --- In tmboptical@yahoogroups.com, "jimhp29401us" <thefamily90@h...>
                          wrote:
                          > Hey, when is the BFSP this year?
                          >
                          > Thanks!
                          >
                          > Jim Phillips

                          Jim,
                          Here is the info.

                          http://www.bfsp.org/starparty/index.cfm?CFID=321248&CFTOKEN=54142091

                          I received an e-mail about 5 days ago saying that there were
                          still about 150 openings. It is always sold out well ahead of time.

                          Harvey
                        • Terry L Tuggle
                          Harvey, Let me say this, If I had it to do over again, and I know what I know now, and was planning to change to CCD imaging, and the F/9.23 was available, I
                          Message 12 of 22 , Jul 3, 2005
                            Harvey,

                            Let me say this, If I had it to do over again, and I know what I know
                            now, and was planning to change to CCD imaging, and the F/9.23 was
                            available, I would choose it over the F/6. At the time I bought my F/6, I
                            had a Meade 127ED f/9 that I was doing film imaging with, and was not even
                            considering CCD imaging. I had been on the waiting list for the 155 edfs for
                            over two years when I read Markus's ads for the new TMB scopes on astromart.
                            Then he was offering 130/780's and the smaller 100's, At that time there
                            were some 6 inch F/6 scopes made, I don't know how many were made, I saw
                            them on the TMB website just after I bought the scope from Markus.

                            Now that I am just starting on the CCD imaging, and have learned on the
                            SBIG website, there is just a small advantage to a faster ratio over a
                            slower ratio on total exposure time while imaging with CCD cameras. It is
                            true that the faster ratio with get to a sky limited sub exposure quicker
                            than a slower scope, the total exposure time is almost the same to achieve
                            the same object s/n ratio. Knowing this, I would choose the F/9.23 over the
                            F/6. There is an imager on the SBIG group using a 6 inch Mak-newt. Using a
                            4x Barlow @ F24, and getting excellent images from that set up. At the same
                            time, if I was still doing film only, I would opt for the F/6, and if I had
                            the long green, I would most definitely go for the 203 F/7. This new 50 cm
                            RC has almost broken the bank for me, it was such a good deal, considering
                            the ROCS/ME alternative, I just could not pass on it.



                            Terry



                            _____

                            From: tmboptical@yahoogroups.com [mailto:tmboptical@yahoogroups.com] On
                            Behalf Of mrgrytt
                            Sent: Sunday, July 03, 2005 3:56 PM
                            To: tmboptical@yahoogroups.com
                            Subject: [tmboptical] Re: TMB 203mm F/7 and 130mm F/9,23 vs. AP 130mm
                            F/f8.35 APO Tests



                            Terry,
                            There are several advantages to a slower f/ratio. Of course
                            whether you consider some things to be an advantage or not all depends
                            on what you want from the scope.
                            For visual use it is an easy choice to make, at least for me.
                            This is without even considering the optical advantage it may have
                            under optimum seeing conditions.
                            You have a flatter field, less sensitive focusing due to greater
                            depth of field, and most eyepiece designs work well. In addition, if
                            a heavier scope weight forces you into a mount with greater capacity I
                            consider that to be a "good thing".
                            For photography you may have to expose a little longer to go as
                            deep, but it's certainly something you can do. If the photographic
                            speed is a big issue you can stick a .75x telecompressor in the system
                            and quickly have a f/6.9 scope. That is certainly fast enough to make
                            me happy.
                            At the risk of mentioning a competitor, a guy named Roland takes
                            some pretty good pictures with a f/14.6 scope, so the f/ratio can't be
                            an "end all" for photography.
                            If you prefer a smaller package, and/or a faster f/ratio, the f/6
                            is the way to go for sure, but you will be giving up some performance
                            in some areas. It's physically impossible not to.
                            Everything in optics is a tradeoff. Whatever you do to gain in
                            one area will cause you to loose in another.
                            It is very fortunate for us that there are people designing
                            equipment that gives us fantastic performance in all areas, regardless
                            of which particular strengths we insist are included in our particular
                            scopes.

                            Harvey

                            -- In tmboptical@yahoogroups.com, "Terry L Tuggle" <tlt284@v...> wrote:
                            > Jim,
                            >
                            > As Tom has said many times, the difference can only be seen during
                            > periods of excellent seeing conditions. As Tim has pointed out the
                            > f/6 has it all. If you were needing a scope for one purpose
                            > ...planetary observing, the f/9.23 would be the better choice.
                            > While it would not make al lot of difference in CCD imaging, for
                            > film work, the f/6 has the best advantage.
                            >
                            > Terry
                            >
                            > >--- In tmboptical@yahoogroups.com, "jimhp29401us" <thefamily90@h...
                            > > wrote:
                            > > I agree Tim. This sounds Great! I purchased a 130 F/6 which is a
                            > > beautiful compact scope but now I am second guessing. That F/9.23
                            > > sounds fantastic.
                            > >
                            > > Jim Phillips






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                            [Non-text portions of this message have been removed]
                          • blandp11
                            Thomas, A long time ago, on the AOL astro boards, you helped me decide between the AP 130 f/6 and the longer f/8.35 version. I choose the f/6, but it was an
                            Message 13 of 22 , Jul 3, 2005
                              Thomas,

                              A long time ago, on the AOL astro boards, you helped me decide between
                              the AP 130 f/6 and the longer f/8.35 version. I choose the f/6, but
                              it was an informed choice. I have never regretted it as a 130 f/6 is
                              an awsome class scope. For those nights of better seeing, I recommend
                              a larger APO!

                              While the 203 f/7 is exciting to me in a theoretical way, I am more
                              interested in hearing about the 180 f/7 as that is more in budget.

                              Philip Blanda

                              --- In tmboptical@yahoogroups.com, "tmboptical" <TMBoptical@a...> wrote:
                              But the f/6
                              > is more versatile, and you can't beat it for its size. And I will
                              > have more to say about it, once I get one good seeing night.
                            • mrgrytt
                              Terry, The nice thing about it is when you choose a TMB lens of any f/ratio you really can t go wrong. It s going to be capable of doing whatever you want it
                              Message 14 of 22 , Jul 3, 2005
                                Terry,
                                The nice thing about it is when you choose a TMB lens of any
                                f/ratio you really can't go wrong. It's going to be capable of doing
                                whatever you want it to do for you. One will simply be a little
                                stronger in one area than another and the differences would be quite
                                hard to detect, for the most part.
                                Your 20 inch RC sounds like a dream scope and is as good a way to
                                "almost" break the bank as any.
                                My only real point in the earlier post was that I think slower
                                f/ratio scopes have had too much undeserved bad press in today's
                                world. I like a heavier scope, a large mount and the most precision
                                the optics can deliver. All personal opinion formed by earlier
                                experience in other areas, of course.
                                I've been pretty deeply into photography since the 1960's and
                                started using a Nikon F2 in 1971 when they first hit the market. The
                                weight of the camera helped a great deal in stability for getting
                                shots you could only get with quite slow shutter speeds, even with the
                                fastest of lenses and the film I preferred. Now everyone wants
                                light-weight cameras. The lighter the better.
                                Yes, I was the guy in the Sistine Chapel making all the
                                "clicking" noises that they couldn't locate. I don't know of any
                                lightweight camera setups that could have pulled that off for me.
                                (that's a long story)
                                I used to shoot rifles in bench rest competition and the heavier
                                the rifle the better. Many people will buy as light a rifle as they
                                can find in a given caliber for hunting, but they give up a lot in the
                                way of stability when they take the shot. They're easier to carry but
                                they have a disadvantage when it comes time to use them. Sometimes it
                                matters, sometimes it doesn't. (I haven't hunted since I've been able
                                to fill the freezer without doing it, and that's been many years now)
                                I guess a lot of that line of thinking has stuck with me over the
                                years. I'll take all the inertia I can get and a longer scope with a
                                heavier capacity mount is no problem, so long as I'm also able to get
                                all the optical performance possible when doing it that way.
                                It's a very comforting thought to know that the scope you are
                                observing through could not be improved upon by anything else of the
                                same aperture. You know what you're seeing is as good as it gets.

                                Harvey


                                --- In tmboptical@yahoogroups.com, "Terry L Tuggle" <tlt284@v...> wrote:
                                > Harvey,
                                >
                                > Let me say this, If I had it to do over again, and I know what
                                I know
                                > now, and was planning to change to CCD imaging, and the F/9.23 was
                                > available, I would choose it over the F/6. At the time I bought my
                                F/6, I
                                > had a Meade 127ED f/9 that I was doing film imaging with, and was
                                not even
                                > considering CCD imaging. I had been on the waiting list for the 155
                                edfs for
                                > over two years when I read Markus's ads for the new TMB scopes on
                                astromart.
                                > Then he was offering 130/780's and the smaller 100's, At that time there
                                > were some 6 inch F/6 scopes made, I don't know how many were made, I saw
                                > them on the TMB website just after I bought the scope from Markus.
                                >
                                > Now that I am just starting on the CCD imaging, and have
                                learned on the
                                > SBIG website, there is just a small advantage to a faster ratio over a
                                > slower ratio on total exposure time while imaging with CCD cameras.
                                It is
                                > true that the faster ratio with get to a sky limited sub exposure
                                quicker
                                > than a slower scope, the total exposure time is almost the same to
                                achieve
                                > the same object s/n ratio. Knowing this, I would choose the F/9.23
                                over the
                                > F/6. There is an imager on the SBIG group using a 6 inch Mak-newt.
                                Using a
                                > 4x Barlow @ F24, and getting excellent images from that set up. At
                                the same
                                > time, if I was still doing film only, I would opt for the F/6, and
                                if I had
                                > the long green, I would most definitely go for the 203 F/7. This new
                                50 cm
                                > RC has almost broken the bank for me, it was such a good deal,
                                considering
                                > the ROCS/ME alternative, I just could not pass on it.
                                >
                                > Terry
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