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

Re: DeepSkyStacker won't stack lights

Expand Messages
  • deepskystacker
    Hi Geoff, In fact your flats are killing the calibration process. They are completely blue/green with very little red preventing the good detection of stars.
    Message 1 of 19 , Nov 1, 2009
    View Source
    • 0 Attachment
      Hi Geoff,

      In fact your flats are killing the calibration process.

      They are completely blue/green with very little red preventing the good detection of stars.

      The workaround is to register without using the flat frames, then stack using them.

      It will still give a redless image but at least you will be able to stack them.

      Clear skies,
      Luc

      --- In DeepSkyStacker@yahoogroups.com, "flyingbat43" <flyingbat43@...> wrote:
      >
      >
      > Sander,
      >
      > Thanks for the reply, I have uploaded 2 x lights , 1 x dark, 2 x flats,
      > We've tried these and they fail to stack on my system. click
      > here
      > <http://download319.mediafire.com/jxje5itln4mg/2jtcidymnun/DSS+Uploaded+\
      > ngc+6723.rar>
      >
      > I've also included the. dssfilelist, Error message screen shot, and Two
      > screen shot of the file list to show Image details .
      >
      > I can only surmise that there is something going on with the flats that
      > DSS doesn't like.
      >
      > Thanks again for your persistance.. Geoff
      >
    • flyingbat43
      Sander, Thanks so much for all your help. It was looking like the Flats were the issue. I ll try a different lightbox and cross my fingers. Many thanks Geoff
      Message 2 of 19 , Nov 1, 2009
      View Source
      • 0 Attachment
        Sander,

        Thanks so much for all your help. It was looking like the Flats were the issue. I'll try a different lightbox and cross my fingers.

        Many thanks Geoff



        --- In DeepSkyStacker@yahoogroups.com, "deepskystacker" <deepskystacker@...> wrote:
        >
        > Hi Geoff,
        >
        > In fact your flats are killing the calibration process.
        >
        > They are completely blue/green with very little red preventing the good detection of stars.
        >
        > The workaround is to register without using the flat frames, then stack using them.
        >
        > It will still give a redless image but at least you will be able to stack them.
        >
        > Clear skies,
        > Luc
        >
        > --- In DeepSkyStacker@yahoogroups.com, "flyingbat43" <flyingbat43@> wrote:
        > >
        > >
        > > Sander,
        > >
        > > Thanks for the reply, I have uploaded 2 x lights , 1 x dark, 2 x flats,
        > > We've tried these and they fail to stack on my system. click
        > > here
        > > <http://download319.mediafire.com/jxje5itln4mg/2jtcidymnun/DSS+Uploaded+\
        > > ngc+6723.rar>
        > >
        > > I've also included the. dssfilelist, Error message screen shot, and Two
        > > screen shot of the file list to show Image details .
        > >
        > > I can only surmise that there is something going on with the flats that
        > > DSS doesn't like.
        > >
        > > Thanks again for your persistance.. Geoff
        > >
        >
      • DaveH
        Does the R/B/G content (ie the color) in flats matter?? If it does.....why have I not heard this before?? What rbg content do we want ?? I honestly have not
        Message 3 of 19 , Nov 1, 2009
        View Source
        • 0 Attachment
          Does the R/B/G content (ie the color) in flats matter??
          If it does.....why have I not heard this before??
          What rbg content do we want ??
          I honestly have not heard of this before...
          On a related note,if my flats are shot at a different ISO...do they get included?
          I see a "warning" note...but how do I know if they went "into the soup mix"..??
          Do I have to go back and change the ISO value (in properties..) to get them included?
          How do we know if DSS has NOT included things...ie the darks were not matching by a certain percentage,etc..
          Finally,maybe its just me...but once I start stacking I cannot seem to be able to "minimize" the DSS widow,OR cancel the operation...
          Why is this ??
          I have just been living with it...but since I am here...(!!!)

          thanks
          Dave

          Dave--- In DeepSkyStacker@yahoogroups.com, "deepskystacker" <deepskystacker@...> wrote:
          >
          > Hi Geoff,
          >
          > In fact your flats are killing the calibration process.
          >
          > They are completely blue/green with very little red preventing the good detection of stars.
          >
          > The workaround is to register without using the flat frames, then stack using them.
          >
          > It will still give a redless image but at least you will be able to stack them.
          >
          > Clear skies,
          > Luc
          >
          > --- In DeepSkyStacker@yahoogroups.com, "flyingbat43" <flyingbat43@> wrote:
          > >
          > >
          > > Sander,
          > >
          > > Thanks for the reply, I have uploaded 2 x lights , 1 x dark, 2 x flats,
          > > We've tried these and they fail to stack on my system. click
          > > here
          > > <http://download319.mediafire.com/jxje5itln4mg/2jtcidymnun/DSS+Uploaded+\
          > > ngc+6723.rar>
          > >
          > > I've also included the. dssfilelist, Error message screen shot, and Two
          > > screen shot of the file list to show Image details .
          > >
          > > I can only surmise that there is something going on with the flats that
          > > DSS doesn't like.
          > >
          > > Thanks again for your persistance.. Geoff
          > >
          >
        • Eelko Gielis
          Hi Dave, What Luc meant with the blue and green is that they are overexposed and the red is nearly/not there. At least your histogram needs to be in between
          Message 4 of 19 , Nov 1, 2009
          View Source
          • 0 Attachment
            Hi Dave,

            What Luc meant with the blue and green is that they are overexposed and the red is nearly/not there.
            At least your histogram needs to be in between 1/4 and 3/4 of the histogram, and the RGB needs to be evenly distributed.

            If your flats are shot with a different ISO setting, they are not taken into the stack, only the ones with the same ISO settings and 0,5% average exposure drift are used.
            This go's for all the frame types.

            The minimize thing is something for Luc, but I think it has to do with the calculations.

            -Eelko.




            ________________________________
            From: DaveH <davehalliday51@...>
            To: DeepSkyStacker@yahoogroups.com
            Sent: Mon, November 2, 2009 3:01:11 AM
            Subject: [DeepSkyStacker] Re: DeepSkyStacker won't stack lights



            Does the R/B/G content (ie the color) in flats matter??
            If it does.....why have I not heard this before??
            What rbg content do we want ??
            I honestly have not heard of this before...
            On a related note,if my flats are shot at a different ISO...do they get included?
            I see a "warning" note...but how do I know if they went "into the soup mix"..??
            Do I have to go back and change the ISO value (in properties.. ) to get them included?
            How do we know if DSS has NOT included things...ie the darks were not matching by a certain percentage,etc. .
            Finally,maybe its just me...but once I start stacking I cannot seem to be able to "minimize" the DSS widow,OR cancel the operation...
            Why is this ??
            I have just been living with it...but since I am here...(!!!)

            thanks
            Dave

            Dave--- In DeepSkyStacker@ yahoogroups. com, "deepskystacker" <deepskystacker@ ...> wrote:
            >
            > Hi Geoff,
            >
            > In fact your flats are killing the calibration process.
            >
            > They are completely blue/green with very little red preventing the good detection of stars.
            >
            > The workaround is to register without using the flat frames, then stack using them.
            >
            > It will still give a redless image but at least you will be able to stack them.
            >
            > Clear skies,
            > Luc
            >
            > --- In DeepSkyStacker@ yahoogroups. com, "flyingbat43" <flyingbat43@ > wrote:
            > >
            > >
            > > Sander,
            > >
            > > Thanks for the reply, I have uploaded 2 x lights , 1 x dark, 2 x flats,
            > > We've tried these and they fail to stack on my system. click
            > > here
            > > <http://download319. mediafire. com/jxje5itln4mg /2jtcidymnun/ DSS+Uploaded+ \
            > > ngc+6723.rar>
            > >
            > > I've also included the. dssfilelist, Error message screen shot, and Two
            > > screen shot of the file list to show Image details .
            > >
            > > I can only surmise that there is something going on with the flats that
            > > DSS doesn't like.
            > >
            > > Thanks again for your persistance. . Geoff
            > >
            >







            [Non-text portions of this message have been removed]
          • deepskystacker
            Hi Dave, ... Of course it does. Each channel is calibrated separately so each content is important. ... Don t know, never been there... ... Each histogram peak
            Message 5 of 19 , Nov 1, 2009
            View Source
            • 0 Attachment
              Hi Dave,

              > Does the R/B/G content (ie the color) in flats matter??
              Of course it does. Each channel is calibrated separately so each content is important.

              > If it does.....why have I not heard this before??
              Don't know, never been there...

              > What rbg content do we want ??
              Each histogram peak between 1/3 and 2/3 and you are set.

              > On a related note,if my flats are shot at a different ISO...do they
              > get included?
              Yes if they are the only one available in the list.

              > Do I have to go back and change the ISO value (in properties..) to
              > get them included?
              In this case, no.

              > How do we know if DSS has NOT included things...ie the darks were
              > not matching by a certain percentage,etc..
              The HTML file generated optionally contains all the used files.


              > Finally,maybe its just me...but once I start stacking I cannot seem
              > to be able to "minimize" the DSS widow,OR cancel the operation...
              > Why is this ??

              Because I was lazy and it's simpler to let it run in the background than have a minimized version of the on going process. I suspect that this will stay that way ;)

              As for canceling it possible using the stop button, just sometimes it does seem to register the command. Try to click on it and/or to press the spacebar until it is graying out.

              Clear skies,
              Luc


              --- In DeepSkyStacker@yahoogroups.com, "DaveH" <davehalliday51@...> wrote:
              >
              >
              > Does the R/B/G content (ie the color) in flats matter??
              > If it does.....why have I not heard this before??
              > What rbg content do we want ??
              > I honestly have not heard of this before...
              > On a related note,if my flats are shot at a different ISO...do they get included?
              > I see a "warning" note...but how do I know if they went "into the soup mix"..??
              > Do I have to go back and change the ISO value (in properties..) to get them included?
              > How do we know if DSS has NOT included things...ie the darks were not matching by a certain percentage,etc..
              > Finally,maybe its just me...but once I start stacking I cannot seem to be able to "minimize" the DSS widow,OR cancel the operation...
              > Why is this ??
              > I have just been living with it...but since I am here...(!!!)
              >
              > thanks
              > Dave
              >
            • Simon
              Dave, I had exactly the same problem last year. I modded my camera and its now extremely sensitive in the red. My flats were taken indoors using the white T
              Message 6 of 19 , Nov 2, 2009
              View Source
              • 0 Attachment
                Dave,

                I had exactly the same problem last year. I modded my camera and its now extremely sensitive in the red. My flats were taken indoors using the white T shirt method with indoor lighting. The result was flats with the red histogram peak way over to the right and the blue and green way over to the left.

                Luc immediately spotted the problem in my flats. I therefore changed to taking flats that match the colours better. I can do this in two ways;

                1. White T shirt over the aperture and pointing at blue sky.
                2. Diffuser over my LCD screen. This lets me tune the colour of the screen so that the three colours on the final flat image are very close.

                It sounds like you are lacking red. The screen tuning method would work for you, but the blue sky wouldn't. Maybe just putting a red lightbulb in the room may be the solution. You'll need to investigate...but its worth looking at the histogram for each colour in the flat and getting them relatively close...at least so that each of them is between say 1/3 and 2/3 full scale.

                Good luck.

                Simon





                > --- In DeepSkyStacker@yahoogroups.com, "DaveH" <davehalliday51@> wrote:
                > >
                > >
                > > Does the R/B/G content (ie the color) in flats matter??
                > > If it does.....why have I not heard this before??
                > > What rbg content do we want ??
                > > I honestly have not heard of this before...
                > > On a related note,if my flats are shot at a different ISO...do they get included?
                > > I see a "warning" note...but how do I know if they went "into the soup mix"..??
                > > Do I have to go back and change the ISO value (in properties..) to get them included?
                > > How do we know if DSS has NOT included things...ie the darks were not matching by a certain percentage,etc..
                > > Finally,maybe its just me...but once I start stacking I cannot seem to be able to "minimize" the DSS widow,OR cancel the operation...
                > > Why is this ??
                > > I have just been living with it...but since I am here...(!!!)
                > >
                > > thanks
                > > Dave
                > >
                >
              • DaveH
                Simon Thanks... Ya there is an issue here,for sure...My brain cells are slowly turning this over... I almost always use per channel calibration ... (It just
                Message 7 of 19 , Nov 2, 2009
                View Source
                • 0 Attachment
                  Simon
                  Thanks...
                  Ya there is an issue here,for sure...My brain cells are slowly turning this over...
                  I almost always use "per channel calibration"...
                  (It just seems to work better...)
                  But maybe that has nothing to do with my flats??

                  I NEVER get the RBG all lined up in my flats,but again...I use (have been using) sky flats...
                  The one thing I DO notice,in my stacked data,is that the red histogram is always wider than the B/G...
                  It certainly bears more thought !!
                  I am just amazed that I have NEVER seen this issue dicscussed...
                  And I am not kidding when I say I have been doing a LOT of reading !!

                  I also wonder how often DSS has even been USING my flats...(!!!) since I generally shoot them at ISO 100/200...
                  I thought the "warning" message was just "polite housekeeping" (computers do that a lot..)
                  Now I am asking myself if they were used (always...)
                  !!!!!!!!

                  Dave


                  --- In DeepSkyStacker@yahoogroups.com, "Simon" <simon.hicks@...> wrote:
                  >
                  >
                  >
                  > Dave,
                  >
                  > I had exactly the same problem last year. I modded my camera and its now extremely sensitive in the red. My flats were taken indoors using the white T shirt method with indoor lighting. The result was flats with the red histogram peak way over to the right and the blue and green way over to the left.
                  >
                  > Luc immediately spotted the problem in my flats. I therefore changed to taking flats that match the colours better. I can do this in two ways;
                  >
                  > 1. White T shirt over the aperture and pointing at blue sky.
                  > 2. Diffuser over my LCD screen. This lets me tune the colour of the screen so that the three colours on the final flat image are very close.
                  >
                  > It sounds like you are lacking red. The screen tuning method would work for you, but the blue sky wouldn't. Maybe just putting a red lightbulb in the room may be the solution. You'll need to investigate...but its worth looking at the histogram for each colour in the flat and getting them relatively close...at least so that each of them is between say 1/3 and 2/3 full scale.
                  >
                  > Good luck.
                  >
                  > Simon
                  >
                  >
                  >
                  >
                  >
                  > > --- In DeepSkyStacker@yahoogroups.com, "DaveH" <davehalliday51@> wrote:
                  > > >
                  > > >
                  > > > Does the R/B/G content (ie the color) in flats matter??
                  > > > If it does.....why have I not heard this before??
                  > > > What rbg content do we want ??
                  > > > I honestly have not heard of this before...
                  > > > On a related note,if my flats are shot at a different ISO...do they get included?
                  > > > I see a "warning" note...but how do I know if they went "into the soup mix"..??
                  > > > Do I have to go back and change the ISO value (in properties..) to get them included?
                  > > > How do we know if DSS has NOT included things...ie the darks were not matching by a certain percentage,etc..
                  > > > Finally,maybe its just me...but once I start stacking I cannot seem to be able to "minimize" the DSS widow,OR cancel the operation...
                  > > > Why is this ??
                  > > > I have just been living with it...but since I am here...(!!!)
                  > > >
                  > > > thanks
                  > > > Dave
                  > > >
                  > >
                  >
                • DaveH
                  The only other though here is...in the master flat ...there is no color at all...just 2 (or sometimes 3) humps in the histogram... Should I be stacking my
                  Message 8 of 19 , Nov 2, 2009
                  View Source
                  • 0 Attachment
                    The only other though here is...in the "master flat"...there is no color at all...just 2 (or sometimes 3) "humps" in the histogram...
                    Should I be stacking my flats using RBG cal or something...?
                    Getting more freaked out by the minute here...

                    Dave

                    --- In DeepSkyStacker@yahoogroups.com, "DaveH" <davehalliday51@...> wrote:
                    >
                    >
                    >
                    > Simon
                    > Thanks...
                    > Ya there is an issue here,for sure...My brain cells are slowly turning this over...
                    > I almost always use "per channel calibration"...
                    > (It just seems to work better...)
                    > But maybe that has nothing to do with my flats??
                    >
                    > I NEVER get the RBG all lined up in my flats,but again...I use (have been using) sky flats...
                    > The one thing I DO notice,in my stacked data,is that the red histogram is always wider than the B/G...
                    > It certainly bears more thought !!
                    > I am just amazed that I have NEVER seen this issue dicscussed...
                    > And I am not kidding when I say I have been doing a LOT of reading !!
                    >
                    > I also wonder how often DSS has even been USING my flats...(!!!) since I generally shoot them at ISO 100/200...
                    > I thought the "warning" message was just "polite housekeeping" (computers do that a lot..)
                    > Now I am asking myself if they were used (always...)
                    > !!!!!!!!
                    >
                    > Dave
                    >
                    >
                    > --- In DeepSkyStacker@yahoogroups.com, "Simon" <simon.hicks@> wrote:
                    > >
                    > >
                    > >
                    > > Dave,
                    > >
                    > > I had exactly the same problem last year. I modded my camera and its now extremely sensitive in the red. My flats were taken indoors using the white T shirt method with indoor lighting. The result was flats with the red histogram peak way over to the right and the blue and green way over to the left.
                    > >
                    > > Luc immediately spotted the problem in my flats. I therefore changed to taking flats that match the colours better. I can do this in two ways;
                    > >
                    > > 1. White T shirt over the aperture and pointing at blue sky.
                    > > 2. Diffuser over my LCD screen. This lets me tune the colour of the screen so that the three colours on the final flat image are very close.
                    > >
                    > > It sounds like you are lacking red. The screen tuning method would work for you, but the blue sky wouldn't. Maybe just putting a red lightbulb in the room may be the solution. You'll need to investigate...but its worth looking at the histogram for each colour in the flat and getting them relatively close...at least so that each of them is between say 1/3 and 2/3 full scale.
                    > >
                    > > Good luck.
                    > >
                    > > Simon
                    > >
                    > >
                    > >
                    > >
                    > >
                    > > > --- In DeepSkyStacker@yahoogroups.com, "DaveH" <davehalliday51@> wrote:
                    > > > >
                    > > > >
                    > > > > Does the R/B/G content (ie the color) in flats matter??
                    > > > > If it does.....why have I not heard this before??
                    > > > > What rbg content do we want ??
                    > > > > I honestly have not heard of this before...
                    > > > > On a related note,if my flats are shot at a different ISO...do they get included?
                    > > > > I see a "warning" note...but how do I know if they went "into the soup mix"..??
                    > > > > Do I have to go back and change the ISO value (in properties..) to get them included?
                    > > > > How do we know if DSS has NOT included things...ie the darks were not matching by a certain percentage,etc..
                    > > > > Finally,maybe its just me...but once I start stacking I cannot seem to be able to "minimize" the DSS widow,OR cancel the operation...
                    > > > > Why is this ??
                    > > > > I have just been living with it...but since I am here...(!!!)
                    > > > >
                    > > > > thanks
                    > > > > Dave
                    > > > >
                    > > >
                    > >
                    >
                  • deepskystacker
                    Hi Dave, ... In fact it has nothing to do with the flat being used. This is applied *after* calibration. ... Again, nothing to do with the flats. It is applied
                    Message 9 of 19 , Nov 2, 2009
                    View Source
                    • 0 Attachment
                      Hi Dave,

                      > I almost always use "per channel calibration"...
                      > (It just seems to work better...)
                      > But maybe that has nothing to do with my flats??

                      In fact it has nothing to do with the flat being used.
                      This is applied *after* calibration.

                      > I NEVER get the RBG all lined up in my flats,but again...I use
                      > have been using) sky flats...

                      Again, nothing to do with the flats.
                      It is applied only to the final stacked image.


                      > The one thing I DO notice,in my stacked data,is that the red
                      > histogram is always wider than the B/G...
                      Using Per channel Background Calibration, it means that this is also the case in your reference frame.


                      > I also wonder how often DSS has even been USING my flats...(!!!)
                      > since I generally shoot them at ISO 100/200...
                      > I thought the "warning" message was just "polite housekeeping"
                      > (computers do that a lot..)
                      The warning is just that: a warning.
                      However, DSS will use them (or it won't bother to warn you about it :) ).


                      Clear skies,
                      Luc

                      --- In DeepSkyStacker@yahoogroups.com, "DaveH" <davehalliday51@...> wrote:
                      >
                      >
                      >
                      > Simon
                      > Thanks...
                      > Ya there is an issue here,for sure...My brain cells are slowly turning this over...
                      > I almost always use "per channel calibration"...
                      > (It just seems to work better...)
                      > But maybe that has nothing to do with my flats??
                      >
                      > I NEVER get the RBG all lined up in my flats,but again...I use (have been using) sky flats...
                      > The one thing I DO notice,in my stacked data,is that the red histogram is always wider than the B/G...
                      > It certainly bears more thought !!
                      > I am just amazed that I have NEVER seen this issue dicscussed...
                      > And I am not kidding when I say I have been doing a LOT of reading !!
                      >
                      > I also wonder how often DSS has even been USING my flats...(!!!) since I generally shoot them at ISO 100/200...
                      > I thought the "warning" message was just "polite housekeeping" (computers do that a lot..)
                      > Now I am asking myself if they were used (always...)
                      > !!!!!!!!
                      >
                      > Dave
                      >
                    • Josh Hufford
                      Dave, to stop the stacking process, try hitting the Esc button, that usually works for me, sometimes I have to hit it a few times. If you want to switch to
                      Message 10 of 19 , Nov 2, 2009
                      View Source
                      • 0 Attachment
                        Dave, to stop the stacking process, try hitting the Esc button, that usually
                        works for me, sometimes I have to hit it a few times. If you want to switch
                        to another application while stacking, try using ALT-TAB.

                        Josh

                        On Mon, Nov 2, 2009 at 8:19 AM, deepskystacker <deepskystacker@...>wrote:

                        >
                        >
                        > Hi Dave,
                        >
                        >
                        > > I almost always use "per channel calibration"...
                        > > (It just seems to work better...)
                        > > But maybe that has nothing to do with my flats??
                        >
                        > In fact it has nothing to do with the flat being used.
                        > This is applied *after* calibration.
                        >
                        >
                        > > I NEVER get the RBG all lined up in my flats,but again...I use
                        > > have been using) sky flats...
                        >
                        > Again, nothing to do with the flats.
                        > It is applied only to the final stacked image.
                        >
                        >
                        > > The one thing I DO notice,in my stacked data,is that the red
                        > > histogram is always wider than the B/G...
                        > Using Per channel Background Calibration, it means that this is also the
                        > case in your reference frame.
                        >
                        >
                        > > I also wonder how often DSS has even been USING my flats...(!!!)
                        > > since I generally shoot them at ISO 100/200...
                        > > I thought the "warning" message was just "polite housekeeping"
                        > > (computers do that a lot..)
                        > The warning is just that: a warning.
                        > However, DSS will use them (or it won't bother to warn you about it :) ).
                        >
                        > Clear skies,
                        > Luc
                        >
                        >
                        > --- In DeepSkyStacker@yahoogroups.com <DeepSkyStacker%40yahoogroups.com>,
                        > "DaveH" <davehalliday51@...> wrote:
                        > >
                        > >
                        > >
                        > > Simon
                        > > Thanks...
                        > > Ya there is an issue here,for sure...My brain cells are slowly turning
                        > this over...
                        > > I almost always use "per channel calibration"...
                        > > (It just seems to work better...)
                        > > But maybe that has nothing to do with my flats??
                        > >
                        > > I NEVER get the RBG all lined up in my flats,but again...I use (have been
                        > using) sky flats...
                        > > The one thing I DO notice,in my stacked data,is that the red histogram is
                        > always wider than the B/G...
                        > > It certainly bears more thought !!
                        > > I am just amazed that I have NEVER seen this issue dicscussed...
                        > > And I am not kidding when I say I have been doing a LOT of reading !!
                        > >
                        > > I also wonder how often DSS has even been USING my flats...(!!!) since I
                        > generally shoot them at ISO 100/200...
                        > > I thought the "warning" message was just "polite housekeeping" (computers
                        > do that a lot..)
                        > > Now I am asking myself if they were used (always...)
                        > > !!!!!!!!
                        > >
                        > > Dave
                        > >
                        >
                        >
                        >


                        [Non-text portions of this message have been removed]
                      • spaceage1939@aol.com
                        Hello Luc Being a novice at the DSS processing, can you tell me what you mean by per channel calibration? What post processing software are you using? I
                        Message 11 of 19 , Nov 4, 2009
                        View Source
                        • 0 Attachment
                          Hello Luc

                          Being a novice at the DSS processing, can you tell me what you mean by "per
                          channel calibration?" What post processing software are you using? I
                          have PS CS4 and having a tough time understanding and accomplishing RGB
                          combining. I also have the older version of CS2 and it seems to be easier....
                          for me anyhow.

                          Thanks.

                          Art


                          In a message dated 11/2/2009 8:19:57 A.M. Central Standard Time,
                          deepskystacker@... writes:




                          Hi Dave,

                          > I almost always use "per channel calibration" I
                          > (It just seems to work better...)
                          > But maybe that has nothing to do with my flats??

                          In fact it has nothing to do with the flat being used.
                          This is applied *after* calibration.

                          > I NEVER get the RBG all lined up in my flats,but again...I use
                          > have been using) sky flats...

                          Again, nothing to do with the flats.
                          It is applied only to the final stacked image.

                          > The one thing I DO notice,in my stacked data,is that the red
                          > histogram is always wider than the B/G...
                          Using Per channel Background Calibration, it means that this is also the
                          case in your reference frame.

                          > I also wonder how often DSS has even been USING my flats...(!!! I
                          > since I generally shoot them at ISO 100/200...
                          > I thought the "warning" message was just "polite housekeeping"
                          > (computers do that a lot..)
                          The warning is just that: a warning.
                          However, DSS will use them (or it won't bother to warn you about it :) ).

                          Clear skies,
                          Luc

                          --- In _DeepSkyStacker@DeepSkyStackDee_
                          (mailto:DeepSkyStacker@yahoogroups.com) , "DaveH" <davehalliday51@dav> wrote:
                          >
                          >
                          >
                          > Simon
                          > Thanks...
                          > Ya there is an issue here,for sure...My brain cells are slowly turning
                          this over...
                          > I almost always use "per channel calibration" I
                          > (It just seems to work better...)
                          > But maybe that has nothing to do with my flats??
                          >
                          > I NEVER get the RBG all lined up in my flats,but again...I use (have
                          been using) sky flats...
                          > The one thing I DO notice,in my stacked data,is that the red histogram
                          is always wider than the B/G...
                          > It certainly bears more thought !!
                          > I am just amazed that I have NEVER seen this issue dicscussed..
                          > And I am not kidding when I say I have been doing a LOT of reading !!
                          >
                          > I also wonder how often DSS has even been USING my flats...(!!! I also
                          wonder how often DSS has even been USING
                          > I thought the "warning" message was just "polite housekeeping"
                          (computers do that a lot..)
                          > Now I am asking myself if they were used (always...)
                          > !!!!!!!!
                          >
                          > Dave
                          >







                          [Non-text portions of this message have been removed]
                        • deepskystacker
                          Hi Art, Per channel calibration is making sure that the peak of each histogram is at the same place in all the light frames. So if in the reference light frame
                          Message 12 of 19 , Nov 4, 2009
                          View Source
                          • 0 Attachment
                            Hi Art,

                            Per channel calibration is making sure that the peak of each histogram is at the same place in all the light frames.

                            So if in the reference light frame you have the peak of red at 15%, green at 21% and blue at 26%, they will be at the same place in all the light frames after the calibration.

                            RGB background calibration does the same thing, but first it puts the peak of the three channels at the same position (minimum, middle or maximum. Your choice).

                            As for post processing, I am using PixInsight Standard.
                            I never was a Photoshop guy which contains (to my taste) too many features unrelated to astrophotographies.

                            Clear skies,
                            Luc

                            --- In DeepSkyStacker@yahoogroups.com, spaceage1939@... wrote:
                            >
                            > Hello Luc
                            >
                            > Being a novice at the DSS processing, can you tell me what you mean by "per
                            > channel calibration?" What post processing software are you using? I
                            > have PS CS4 and having a tough time understanding and accomplishing RGB
                            > combining. I also have the older version of CS2 and it seems to be easier....
                            > for me anyhow.
                            >
                            > Thanks.
                            >
                            > Art
                            >
                          Your message has been successfully submitted and would be delivered to recipients shortly.