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

RE: [ccd-newastro] Weird collimation problem

Expand Messages
  • Wodaski Yahoo
    The images are too small to evaluate properly. One needs to look at the shape of the stars to tell anything. At this size, I really don t see anything that
    Message 1 of 13 , Sep 30 10:20 PM
    • 0 Attachment
      The images are too small to evaluate properly. One needs to look at the
      shape of the stars to tell anything. At this size, I really don't see
      anything that looks like a miscollimation. I don't see any evidence of a
      ring.

      I doubt that you can do any permanent damage. You could get collimation way
      off, but even if you did you could get it back.

      Poor collimation typically shows star with tails. The background brightness
      is certainly from the bright moon, and means absolutely nothing at all with
      respect to collimation.

      This is an SCT, so you have to expect some level of collimation change due
      to the primary mirror shifting. It shouldn't be a large effect, however.

      So, first, let's determine if in fact you are seeing changes that have
      something to do with collimation, or not. Then we can diagnose and move on.

      If you are going to post images, please put them in the Files section. You
      can put a JPG there and leave it at a large size (tests of collimation must
      be done unbinned to get the largest view possible of the star shapes). FITS
      files are a possibility, but if you have your own web site where we could
      download FITS files, that is better because the storage space for files is
      limited.

      Ron Wodaski
      The New CCD Astronomy
      http://www.newastro.com/ipb

      -----Original Message-----
      From: Jason Hissong [mailto:jhisson1@...]
      Sent: Thursday, September 30, 2004 11:04 PM
      To: ccd-newastro@yahoogroups.com
      Subject: [ccd-newastro] Weird collimation problem

      Hi guys,

      First time posting here.. need some help. I attempted to collimate my
      Ultima 2000 and I think I just messed everything up.

      Now, it seems that the collimation does not hold. I get it dead on,
      but it seems to shift from image to image:

      http://photos.groups.yahoo.com/group/ccd-newastro/vwp?.dir=/jhissong&.dnm=ba
      d1.jpg&.src=gr&.view=t&.hires=t
      http://photos.groups.yahoo.com/group/ccd-newastro/vwp?.dir=/jhissong&.dnm=ba
      d2.jpg&.src=gr&.done=http%3a//photos.groups.yahoo.com/group/ccd-newastro/vwp
      %3f.dir=/jhissong%26.dnm=bad1.jpg%26.src=gr

      A couple of things, the first image just looks weird. This was during
      a bright moon which I am sure causes the brighter background, but the
      pattern just looks very weird.

      The second one you can see that a ring is beginning to form.

      This is what things looked like before:
      http://photos.groups.yahoo.com/group/ccd-newastro/vwp?.dir=/jhissong&.dnm=go
      od.jpg&.src=gr&.view=t&.hires=t

      I should have left it alone :(

      I am concerned that my scope will never hold collimation again. I
      will admit that I probably loosened the screws too much at one time
      while trying to find out what direction the screw movement was causing
      the center "hole" to move around. I have since tighted them up pretty
      good (hand tight, not torqued). I thought I got it right, but then it
      still shifted.

      Thanks guys...

      Jason






      Yahoo! Groups Links







      __________ NOD32 1.881 (20040930) Information __________

      This message was checked by NOD32 antivirus system.
      http://www.nod32.com
    • Jason Hissong
      Ron, Thanks for such a quick reply. I will post the FITS files on my website. One way to describe this is the stars look fine, however, it is like the
      Message 2 of 13 , Oct 1, 2004
      • 0 Attachment
        Ron,

        Thanks for such a quick reply. I will post the FITS files on my
        website. One way to describe this is the stars look fine, however, it
        is like the entire optical path changed. This is the first time taking
        shots during a moon too.

        Thanks

        Jason

        Wodaski Yahoo wrote:

        >The images are too small to evaluate properly. One needs to look at the
        >shape of the stars to tell anything. At this size, I really don't see
        >anything that looks like a miscollimation. I don't see any evidence of a
        >ring.
        >
        >I doubt that you can do any permanent damage. You could get collimation way
        >off, but even if you did you could get it back.
        >
        >Poor collimation typically shows star with tails. The background brightness
        >is certainly from the bright moon, and means absolutely nothing at all with
        >respect to collimation.
        >
        >This is an SCT, so you have to expect some level of collimation change due
        >to the primary mirror shifting. It shouldn't be a large effect, however.
        >
        >So, first, let's determine if in fact you are seeing changes that have
        >something to do with collimation, or not. Then we can diagnose and move on.
        >
        >If you are going to post images, please put them in the Files section. You
        >can put a JPG there and leave it at a large size (tests of collimation must
        >be done unbinned to get the largest view possible of the star shapes). FITS
        >files are a possibility, but if you have your own web site where we could
        >download FITS files, that is better because the storage space for files is
        >limited.
        >
        >Ron Wodaski
        >The New CCD Astronomy
        >http://www.newastro.com/ipb
        >
        >
        >
        >

        --

        "A long journey starts with the first step and an understanding spouse."
        http://www.n8xe.com
        http://www.jasonhissong.com
      • eja24601
        Jason, The pictures do indeed look too small for me to judge as well, but as far as the ring (especially with the 2nd picture), did it expand and eventually
        Message 3 of 13 , Oct 1, 2004
        • 0 Attachment
          Jason,

          The pictures do indeed look too small for me to judge as well, but
          as far as the "ring" (especially with the 2nd picture), did it
          expand and eventually disappear? If so, that's frost forming on your
          chip. Which is fine; you just need to bake the camera's dessicant.
          The rest of the artifacts look like stuff that could either be taken
          out with a flat or gradient removal. Of course, I am basing all this
          on first impressions with small pictures, so YMMV.

          HTH,
          Eric

          --- In ccd-newastro@yahoogroups.com, Jason Hissong <jhisson1@c...>
          wrote:
          > Ron,
          >
          > Thanks for such a quick reply. I will post the FITS files on my
          > website. One way to describe this is the stars look fine,
          however, it
          > is like the entire optical path changed. This is the first time
          taking
          > shots during a moon too.
          >
          > Thanks
          >
          > Jason
          >
          > Wodaski Yahoo wrote:
          >
          > >The images are too small to evaluate properly. One needs to look
          at the
          > >shape of the stars to tell anything. At this size, I really don't
          see
          > >anything that looks like a miscollimation. I don't see any
          evidence of a
          > >ring.
          > >
          > >I doubt that you can do any permanent damage. You could get
          collimation way
          > >off, but even if you did you could get it back.
          > >
          > >Poor collimation typically shows star with tails. The background
          brightness
          > >is certainly from the bright moon, and means absolutely nothing
          at all with
          > >respect to collimation.
          > >
          > >This is an SCT, so you have to expect some level of collimation
          change due
          > >to the primary mirror shifting. It shouldn't be a large effect,
          however.
          > >
          > >So, first, let's determine if in fact you are seeing changes that
          have
          > >something to do with collimation, or not. Then we can diagnose
          and move on.
          > >
          > >If you are going to post images, please put them in the Files
          section. You
          > >can put a JPG there and leave it at a large size (tests of
          collimation must
          > >be done unbinned to get the largest view possible of the star
          shapes). FITS
          > >files are a possibility, but if you have your own web site where
          we could
          > >download FITS files, that is better because the storage space for
          files is
          > >limited.
          > >
          > >Ron Wodaski
          > >The New CCD Astronomy
          > >http://www.newastro.com/ipb
          > >
          > >
          > >
          > >
          >
          > --
          >
          > "A long journey starts with the first step and an understanding
          spouse."
          > http://www.n8xe.com
          > http://www.jasonhissong.com
        • Wodaski Yahoo
          I had a loose secondary assembly once that cause big shifts. The collar around the secondary became loose; the three collimation screws were not loose. Ron
          Message 4 of 13 , Oct 1, 2004
          • 0 Attachment
            I had a loose secondary assembly once that cause big shifts. The collar
            around the secondary became loose; the three collimation screws were not
            loose.


            Ron Wodaski
            The New CCD Astronomy
            http://www.newastro.com/ipb

            -----Original Message-----
            From: Jason Hissong [mailto:jhisson1@...]
            Sent: Friday, October 01, 2004 6:29 AM
            To: ccd-newastro@yahoogroups.com
            Subject: Re: [ccd-newastro] Weird collimation problem

            Ron,

            Thanks for such a quick reply. I will post the FITS files on my
            website. One way to describe this is the stars look fine, however, it
            is like the entire optical path changed. This is the first time taking
            shots during a moon too.

            Thanks

            Jason

            Wodaski Yahoo wrote:

            >The images are too small to evaluate properly. One needs to look at the
            >shape of the stars to tell anything. At this size, I really don't see
            >anything that looks like a miscollimation. I don't see any evidence of a
            >ring.
            >
            >I doubt that you can do any permanent damage. You could get collimation way
            >off, but even if you did you could get it back.
            >
            >Poor collimation typically shows star with tails. The background brightness
            >is certainly from the bright moon, and means absolutely nothing at all with
            >respect to collimation.
            >
            >This is an SCT, so you have to expect some level of collimation change due
            >to the primary mirror shifting. It shouldn't be a large effect, however.
            >
            >So, first, let's determine if in fact you are seeing changes that have
            >something to do with collimation, or not. Then we can diagnose and move on.
            >
            >If you are going to post images, please put them in the Files section. You
            >can put a JPG there and leave it at a large size (tests of collimation must
            >be done unbinned to get the largest view possible of the star shapes). FITS
            >files are a possibility, but if you have your own web site where we could
            >download FITS files, that is better because the storage space for files is
            >limited.
            >
            >Ron Wodaski
            >The New CCD Astronomy
            >http://www.newastro.com/ipb
            >
            >
            >
            >

            --

            "A long journey starts with the first step and an understanding spouse."
            http://www.n8xe.com
            http://www.jasonhissong.com






            Yahoo! Groups Links







            __________ NOD32 1.881 (20040930) Information __________

            This message was checked by NOD32 antivirus system.
            http://www.nod32.com
          • Jason Hissong
            Thanks Eric and Ron, I have uploaded the raw files to my website. Yes, the ring definately was expanding. I did not let it go far enough to clear all the way
            Message 5 of 13 , Oct 1, 2004
            • 0 Attachment
              Thanks Eric and Ron,

              I have uploaded the raw files to my website. Yes, the ring definately
              was expanding. I did not let it go far enough to clear all the way out.

              The camera is about three years old and I have been using it quite
              frequently lately. I can say that I shutdown the computer before
              turning off the cooling a couple times by accident. I know that it can
              increase the chance of thermal shock but I don't know if that would all
              of a sudden cause this type of behavior. Basically, one night it looks
              as good as this:

              http://www.n8xe.com/astronomy/images/issues/m29.FIT

              To these:

              http://www.n8xe.com/astronomy/images/issues/sn2004et.00000000.FIT
              http://www.n8xe.com/astronomy/images/issues/sn2004et.00000002.FIT
              http://www.n8xe.com/astronomy/images/issues/sw_cyg.FIT
              http://www.n8xe.com/astronomy/images/issues/test.FIT

              Here is a flatfield:

              http://www.n8xe.com/astronomy/images/issues/testflat.FIT

              I thought that the first image with the weird patterns was because I had
              my secondary adjusted too tight. The more I think about the problem,
              the more I think it could be frosting and not collimation.

              Thanks for the insight guys!!

              Jason


              eja24601 wrote:

              >Jason,
              >
              >The pictures do indeed look too small for me to judge as well, but
              >as far as the "ring" (especially with the 2nd picture), did it
              >expand and eventually disappear? If so, that's frost forming on your
              >chip. Which is fine; you just need to bake the camera's dessicant.
              >The rest of the artifacts look like stuff that could either be taken
              >out with a flat or gradient removal. Of course, I am basing all this
              >on first impressions with small pictures, so YMMV.
              >
              >HTH,
              >Eric
              >
              >
              >
            • Randy Nulman
              Hi Jason, I don t see any collimation issues...just what strongly looks like a frost issue. Probably, if you raised your ccd temp a bit, it would have gone
              Message 6 of 13 , Oct 1, 2004
              • 0 Attachment
                Hi Jason,
                I don't see any collimation issues...just what strongly looks like a
                frost issue. Probably, if you raised your ccd temp a bit, it would
                have gone away...but time to bake the dessicant.

                Remove the dessicant plug and replace with the "dummy"...include the
                o-ring. Then, without the o-ring on the actual dessicant plug (it
                will not like the heat <g>), bake the dessicant plug at 350 degrees
                F for 4 hours. As soon as it is cool enough to handle by hand (just
                a minute or two after removing from the oven), replace it back into
                the camera. Wait at least 6 hours to be safe and all should be well.

                Randy Nulman
                http://www.nulman.darkhorizons.org


                --- In ccd-newastro@yahoogroups.com, Jason Hissong <jhisson1@c...>
                wrote:
                > Thanks Eric and Ron,
                >
                > I have uploaded the raw files to my website. Yes, the ring
                definately
                > was expanding. I did not let it go far enough to clear all the
                way out.
                >
                > The camera is about three years old and I have been using it quite
                > frequently lately. I can say that I shutdown the computer before
                > turning off the cooling a couple times by accident. I know that
                it can
                > increase the chance of thermal shock but I don't know if that
                would all
                > of a sudden cause this type of behavior. Basically, one night it
                looks
                > as good as this:
                >
                > http://www.n8xe.com/astronomy/images/issues/m29.FIT
                >
                > To these:
                >
                > http://www.n8xe.com/astronomy/images/issues/sn2004et.00000000.FIT
                > http://www.n8xe.com/astronomy/images/issues/sn2004et.00000002.FIT
                > http://www.n8xe.com/astronomy/images/issues/sw_cyg.FIT
                > http://www.n8xe.com/astronomy/images/issues/test.FIT
                >
                > Here is a flatfield:
                >
                > http://www.n8xe.com/astronomy/images/issues/testflat.FIT
                >
                > I thought that the first image with the weird patterns was because
                I had
                > my secondary adjusted too tight. The more I think about the
                problem,
                > the more I think it could be frosting and not collimation.
                >
                > Thanks for the insight guys!!
                >
                > Jason
                >
                >
                > eja24601 wrote:
                >
                > >Jason,
                > >
                > >The pictures do indeed look too small for me to judge as well,
                but
                > >as far as the "ring" (especially with the 2nd picture), did it
                > >expand and eventually disappear? If so, that's frost forming on
                your
                > >chip. Which is fine; you just need to bake the camera's
                dessicant.
                > >The rest of the artifacts look like stuff that could either be
                taken
                > >out with a flat or gradient removal. Of course, I am basing all
                this
                > >on first impressions with small pictures, so YMMV.
                > >
                > >HTH,
                > >Eric
                > >
                > >
                > >
              • eja24601
                Jason, If the pictures are presented in the order that you took them, with the ring expanding with each succeeding picture, that would indeed tell me that it s
                Message 7 of 13 , Oct 1, 2004
                • 0 Attachment
                  Jason,

                  If the pictures are presented in the order that you took them, with
                  the ring expanding with each succeeding picture, that would indeed
                  tell me that it's "just" frost. This happened to me once, and since I
                  suspected it as such (I was using a refractor, so it definitely was
                  not a collimation issue), I just watched, initially with concern,
                  then later on with amusement, as the ring expanded and then
                  dissipated. Your pictures of the ring look a lot like mine from that
                  evening.

                  Try baking the dessicant (SBIG recommends doing that at least once a
                  year - mine has passed that mark) and see how it goes. That is, of
                  course, assuming there is something else going on.

                  HTH,
                  Eric

                  --- In ccd-newastro@yahoogroups.com, Jason Hissong <jhisson1@c...>
                  wrote:
                  > Thanks Eric and Ron,
                  >
                  > I have uploaded the raw files to my website. Yes, the ring
                  definately
                  > was expanding. I did not let it go far enough to clear all the way
                  out.
                  >
                  > The camera is about three years old and I have been using it quite
                  > frequently lately. I can say that I shutdown the computer before
                  > turning off the cooling a couple times by accident. I know that it
                  can
                  > increase the chance of thermal shock but I don't know if that would
                  all
                  > of a sudden cause this type of behavior. Basically, one night it
                  looks
                  > as good as this:
                  >
                  > http://www.n8xe.com/astronomy/images/issues/m29.FIT
                  >
                  > To these:
                  >
                  > http://www.n8xe.com/astronomy/images/issues/sn2004et.00000000.FIT
                  > http://www.n8xe.com/astronomy/images/issues/sn2004et.00000002.FIT
                  > http://www.n8xe.com/astronomy/images/issues/sw_cyg.FIT
                  > http://www.n8xe.com/astronomy/images/issues/test.FIT
                  >
                  > Here is a flatfield:
                  >
                  > http://www.n8xe.com/astronomy/images/issues/testflat.FIT
                  >
                  > I thought that the first image with the weird patterns was because
                  I had
                  > my secondary adjusted too tight. The more I think about the
                  problem,
                  > the more I think it could be frosting and not collimation.
                  >
                  > Thanks for the insight guys!!
                  >
                  > Jason
                  >
                • Jason Hissong
                  Guys, I appreciate the info. I was freaking out when it was only something to be expected, sheesh! This is why we have groups like this to help us newbies
                  Message 8 of 13 , Oct 1, 2004
                  • 0 Attachment
                    Guys,

                    I appreciate the info. I was freaking out when it was only something to
                    be expected, sheesh! This is why we have groups like this to help us
                    newbies out.

                    I just borrowed a manual filter wheel to try my hand at RGB imaging.
                    Going to Ron's great book to read up on it.

                    Thanks guys!!

                    Jason Hissong

                    BTW.. here are some examples of some of the stuff I have been doing. I
                    am still starting out. I think they are too over processed, but I am
                    getting better.

                    http://www.n8xe.com/astronomy/st7_astrophotography.htm

                    eja24601 wrote:

                    >Jason,
                    >
                    >If the pictures are presented in the order that you took them, with
                    >the ring expanding with each succeeding picture, that would indeed
                    >tell me that it's "just" frost. This happened to me once, and since I
                    >suspected it as such (I was using a refractor, so it definitely was
                    >not a collimation issue), I just watched, initially with concern,
                    >then later on with amusement, as the ring expanded and then
                    >dissipated. Your pictures of the ring look a lot like mine from that
                    >evening.
                    >
                    >Try baking the dessicant (SBIG recommends doing that at least once a
                    >year - mine has passed that mark) and see how it goes. That is, of
                    >course, assuming there is something else going on.
                    >
                    >HTH,
                    >Eric
                    >
                    >

                    --

                    "A long journey starts with the first step and an understanding spouse."
                    http://www.n8xe.com
                    http://www.jasonhissong.com
                  • Wodaski Yahoo
                    That s classic frost. How humid is your air? In addition to getting frost inside the camera and needing to recharge the desiccant, you can also get front on
                    Message 9 of 13 , Oct 2, 2004
                    • 0 Attachment
                      That's classic frost. How humid is your air? In addition to getting frost
                      inside the camera and needing to recharge the desiccant, you can also get
                      front on the outside of the chip chamber or on the camera's window. A quick
                      look with a flashlight might help you determine exactly where the frost is.

                      A cold, damp night can cause frosting _outside_ the chip chamber.
                      Frequently, this is because there has been so much condensation that it has
                      dripped inside the camera (on cameras that have open outer cases). This
                      moisture then increases the humidity inside the camera, and allows frost on
                      the outside of the chip chamber.


                      Ron Wodaski
                      The New CCD Astronomy
                      http://www.newastro.com/ipb

                      -----Original Message-----
                      From: Jason Hissong [mailto:jhisson1@...]
                      Sent: Friday, October 01, 2004 8:28 PM
                      To: ccd-newastro@yahoogroups.com
                      Subject: Re: [ccd-newastro] Re: Weird collimation problem


                      Thanks Eric and Ron,

                      I have uploaded the raw files to my website. Yes, the ring definately
                      was expanding. I did not let it go far enough to clear all the way out.

                      The camera is about three years old and I have been using it quite
                      frequently lately. I can say that I shutdown the computer before
                      turning off the cooling a couple times by accident. I know that it can
                      increase the chance of thermal shock but I don't know if that would all
                      of a sudden cause this type of behavior. Basically, one night it looks
                      as good as this:

                      http://www.n8xe.com/astronomy/images/issues/m29.FIT

                      To these:

                      http://www.n8xe.com/astronomy/images/issues/sn2004et.00000000.FIT
                      http://www.n8xe.com/astronomy/images/issues/sn2004et.00000002.FIT
                      http://www.n8xe.com/astronomy/images/issues/sw_cyg.FIT
                      http://www.n8xe.com/astronomy/images/issues/test.FIT

                      Here is a flatfield:

                      http://www.n8xe.com/astronomy/images/issues/testflat.FIT

                      I thought that the first image with the weird patterns was because I had
                      my secondary adjusted too tight. The more I think about the problem,
                      the more I think it could be frosting and not collimation.

                      Thanks for the insight guys!!

                      Jason


                      eja24601 wrote:

                      >Jason,
                      >
                      >The pictures do indeed look too small for me to judge as well, but
                      >as far as the "ring" (especially with the 2nd picture), did it
                      >expand and eventually disappear? If so, that's frost forming on your
                      >chip. Which is fine; you just need to bake the camera's dessicant.
                      >The rest of the artifacts look like stuff that could either be taken
                      >out with a flat or gradient removal. Of course, I am basing all this
                      >on first impressions with small pictures, so YMMV.
                      >
                      >HTH,
                      >Eric
                      >
                      >
                      >






                      Yahoo! Groups Links









                      __________ NOD32 1.881 (20040930) Information __________

                      This message was checked by NOD32 antivirus system.
                      http://www.nod32.com
                    • Jason Hissong
                      Ron, I live in Columbus, OH which in the summer gets humid, but in the fall it is not as humid. I am baking the desiccant right now... my wife is giving me
                      Message 10 of 13 , Oct 2, 2004
                      • 0 Attachment
                        Ron,

                        I live in Columbus, OH which in the summer gets humid, but in the fall
                        it is not as humid.

                        I am baking the desiccant right now... my wife is giving me funny
                        stares... ;-)

                        Jason

                        Wodaski Yahoo wrote:

                        >That's classic frost. How humid is your air? In addition to getting frost
                        >inside the camera and needing to recharge the desiccant, you can also get
                        >front on the outside of the chip chamber or on the camera's window. A quick
                        >look with a flashlight might help you determine exactly where the frost is.
                        >
                        >A cold, damp night can cause frosting _outside_ the chip chamber.
                        >Frequently, this is because there has been so much condensation that it has
                        >dripped inside the camera (on cameras that have open outer cases). This
                        >moisture then increases the humidity inside the camera, and allows frost on
                        >the outside of the chip chamber.
                        >
                        >
                        >Ron Wodaski
                        >The New CCD Astronomy
                        >http://www.newastro.com/ipb
                        >
                        >
                        >

                        --

                        "A long journey starts with the first step and an understanding spouse."
                        http://www.n8xe.com
                        http://www.jasonhissong.com
                      • Don Waid
                        Jason, After I bake my desiccant plug, I put it directly into a clean, very small, fruit jar with an air tight cap. I let it cool in the jar and then put it
                        Message 11 of 13 , Oct 2, 2004
                        • 0 Attachment
                          Jason,

                          After I bake my desiccant plug, I put it directly into a clean, very small, fruit jar with an air tight cap. I let it cool in the jar and then put it directly into the camera. This keeps it from absorbing moisture in my humid Florida air while it cools. I don't know if this is necessary, but I saw the tip on another group. The SBIG group, if I remember correctly.

                          Don Waid



                          ----- Original Message -----
                          From: Jason Hissong
                          To: ccd-newastro@yahoogroups.com
                          Sent: Saturday, October 02, 2004 4:45 PM
                          Subject: Re: [ccd-newastro] Re: Weird collimation problem


                          Ron,

                          I live in Columbus, OH which in the summer gets humid, but in the fall
                          it is not as humid.

                          I am baking the desiccant right now... my wife is giving me funny
                          stares... ;-)

                          Jason

                          Wodaski Yahoo wrote:

                          >That's classic frost. How humid is your air? In addition to getting frost
                          >inside the camera and needing to recharge the desiccant, you can also get
                          >front on the outside of the chip chamber or on the camera's window. A quick
                          >look with a flashlight might help you determine exactly where the frost is.
                          >
                          >A cold, damp night can cause frosting _outside_ the chip chamber.
                          >Frequently, this is because there has been so much condensation that it has
                          >dripped inside the camera (on cameras that have open outer cases). This
                          >moisture then increases the humidity inside the camera, and allows frost on
                          >the outside of the chip chamber.
                          >
                          >
                          >Ron Wodaski
                          >The New CCD Astronomy
                          >http://www.newastro.com/ipb
                          >
                          >
                          >

                          --

                          "A long journey starts with the first step and an understanding spouse."
                          http://www.n8xe.com
                          http://www.jasonhissong.com







                          Yahoo! Groups Sponsor
                          ADVERTISEMENT





                          ------------------------------------------------------------------------------
                          Yahoo! Groups Links

                          a.. To visit your group on the web, go to:
                          http://groups.yahoo.com/group/ccd-newastro/

                          b.. To unsubscribe from this group, send an email to:
                          ccd-newastro-unsubscribe@yahoogroups.com

                          c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.



                          [Non-text portions of this message have been removed]
                        • Randy Nulman
                          Don, My experience has been that the plug cools so quickly..within a minute or so to handle safely..that I just put it straight back in the camera. However, I
                          Message 12 of 13 , Oct 3, 2004
                          • 0 Attachment
                            Don,
                            My experience has been that the plug cools so quickly..within a
                            minute or so to handle safely..that I just put it straight back in
                            the camera. However, I don't have the humidity you guys do, so
                            maybe that's a consideration. Also, my experience is to wait at
                            least 6 hours before using the camera to allow the "recharged"
                            dessicant to absorb existing moisture....then my old ST8 would
                            typically be good for almost a year...YMMV.

                            Randy Nulman
                            http://www.nulman.darkhorizons.org


                            --- In ccd-newastro@yahoogroups.com, "Don Waid" <don@a...> wrote:
                            > Jason,
                            >
                            > After I bake my desiccant plug, I put it directly into a clean,
                            very small, fruit jar with an air tight cap. I let it cool in the
                            jar and then put it directly into the camera. This keeps it from
                            absorbing moisture in my humid Florida air while it cools. I don't
                            know if this is necessary, but I saw the tip on another group. The
                            SBIG group, if I remember correctly.
                            >
                            > Don Waid
                            >
                            >
                            >
                            > ----- Original Message -----
                            > From: Jason Hissong
                            > To: ccd-newastro@yahoogroups.com
                            > Sent: Saturday, October 02, 2004 4:45 PM
                            > Subject: Re: [ccd-newastro] Re: Weird collimation problem
                            >
                            >
                            > Ron,
                            >
                            > I live in Columbus, OH which in the summer gets humid, but in
                            the fall
                            > it is not as humid.
                            >
                            > I am baking the desiccant right now... my wife is giving me
                            funny
                            > stares... ;-)
                            >
                            > Jason
                            >
                            > Wodaski Yahoo wrote:
                            >
                            > >That's classic frost. How humid is your air? In addition to
                            getting frost
                            > >inside the camera and needing to recharge the desiccant, you
                            can also get
                            > >front on the outside of the chip chamber or on the camera's
                            window. A quick
                            > >look with a flashlight might help you determine exactly where
                            the frost is.
                            > >
                            > >A cold, damp night can cause frosting _outside_ the chip
                            chamber.
                            > >Frequently, this is because there has been so much condensation
                            that it has
                            > >dripped inside the camera (on cameras that have open outer
                            cases). This
                            > >moisture then increases the humidity inside the camera, and
                            allows frost on
                            > >the outside of the chip chamber.
                            > >
                            > >
                            > >Ron Wodaski
                            > >The New CCD Astronomy
                            > >http://www.newastro.com/ipb
                            > >
                            > >
                            > >
                            >
                            > --
                            >
                            > "A long journey starts with the first step and an understanding
                            spouse."
                            > http://www.n8xe.com
                            > http://www.jasonhissong.com
                            >
                            >
                            >
                            >
                            >
                            >
                            >
                            > Yahoo! Groups Sponsor
                            > ADVERTISEMENT
                            >
                            >
                            >
                            >
                            >
                            > -------------------------------------------------------------------
                            -----------
                            > Yahoo! Groups Links
                            >
                            > a.. To visit your group on the web, go to:
                            > http://groups.yahoo.com/group/ccd-newastro/
                            >
                            > b.. To unsubscribe from this group, send an email to:
                            > ccd-newastro-unsubscribe@yahoogroups.com
                            >
                            > c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms
                            of Service.
                            >
                            >
                            >
                            > [Non-text portions of this message have been removed]
                          Your message has been successfully submitted and would be delivered to recipients shortly.