Now I am really confused......Putting aside the lens/eyepiece image reversal issue for
now.....and again assuming a straight thru refractor on an Eq. mount, then:

What I think you are saying is that the Pictor orientation has to be calibrated as a
visually estimated angle measured from the camera button orientation to a direction
along a plane in a (curved) line directly from the center of the camera to Polaris (or 0
degree North), even though that direction is 180 degrees opposite of the (North)
direction as far as the (Business) end of the telescope is concerned. If this is true,
then it is not a very good way of doing it. First of all, at certain telescope pointing
angles it is difficult to site up the camera orientation and estimate this angle.
Second, it is based on a visual approximation and not an angle that can be measured in
any way.

The algorithim for setting the pictor orientation angle should be referenced against the
telescope (business end slewing) direction of NSEW. not the actual direction (as the
crow flys). The orientation procedure for the pictor when standalone guiding is a good
example, it says to: "have the pictor (writing) oriented parallel to the (EW) RA slewing
plane as viewed thru an eyepiece". Thats real simple, just press the (EW) keys while
viewing thru a (reticle) eyepiece, watch which way the star moves and then insert and
orient the pictor accordingly. By doing it this way, a diagonal is already taken into
consideration. If you wanted to allow someone to change this and set an angle as
compared to (N), that would be good, in case someone has to orient the pictor in a
certain way for (wire) clearance. My assumption has always been that the pictor just
wants to know that if a star moves up in the field, that it is either north or south,
and if it moves left, is it either east or west.

If you can confirm that my spin on this is correct, then I think I understand it.

m.

Ralph P. Pass III wrote:

> Yes, as I understand what you have written, this is reversed. I also read your
> discription as having the scope pointing on the east side of the meridian in the
> northern hemisphere. The reason that I think this is reversed is because the
> eyepiece inverts the image. As such, the appearance of 'South' in the eyepiece is
> in the direction of the North Celestial Pole. As you move the telescope to point
> further north the eyepiece end will move south. So to have an offset angle of zero,
> you should put the button on the Pictor away from the direction of travel of the
> eyepiece end as you increase the declination angle of the telescope.
>
> Verify by a test! Should not take but a couple of minutes.
>
> Does this help???
>
> Ralph
>
> M. Gartland wrote:
>
> > It's probably me, but I still can't see it. I 'd be more than happy to write a
> > clarifying procedure, but I need to understand it first.
> >
> > Let me propose a simple scenario that could clarify it all..........
> >
> > 1 - Suppose I have my (EQ mount) refractor telescope set up, polar aligned and
> > tracking on another star (not polaris). Also, suppose I am using a reticle
> > (crosshair) eyepiece and no diagonal. I then push the (N) key on the handbox and
> > observe the star move across the eyepiece field directly to the left. Then, I
> > remove the eyepeice and install the 216xt with the button facing (I think)
> > directly right (180 degress opposite of the way the star moved because the star
> > in the eyepiece moves opposite of the actual telescope slewing direction). I
> > then dial in an angle in Pview (FOV calculator) of 0 degrees for pictor
> > orientation because the Pictor "UP" is now aligned directly in the "North"
> > direction. This setup would now be good for any object on this side of the
> > meridian.
> >
> > 2 - However, if I now slew to an object or star on the "other" side of the
> > meridian, I would have to change the pictor orientation in Pview (FOV
> > calculator) screen from 0 degrees to 180 degrees because the orientation of the
> > EQ mount to North for slewing purposes is opposite as from before.
> >
> > Can you follow and confirm the above? The only area I think I am really guessing
> > on is in aligning the button to the "Right" as opposed to "Left" in number (1),
> > I may have that backwards.
> >
> > Thanks for helping!
> > m.
> >
> > Ralph P. Pass III wrote:
> >
> > > Yes, the buttom above the word Meade indicates the marker position. For a
> > > Fork mount the orientation angle is independent of where you are pointing
> > > the telescope. For an equatorial mount it is independent if you stay on the
> > > same side of the mount. It changes by 180 degrees if you go the other side.
> > >
> > > I am not familiar with the 'focus lock' or where it is. However, for one
> > > side of the meridian this is correct and for the other it is 180 degrees off
> > > (see the prior paragraph).
> > >
> > > I am afraid I am not familiar enough with the LXD mount to answer other
> > > questions. The intend of this angle is to provide the software with an
> > > indication of the direction of North on the chip. You do not need to be
> > > perfect, but the closer the better.
> > >
> > > If you can imagine a line from the center of the back of the pictor pointing
> > > at the north star. You then estimate the angle between that line and a line
> > > from the center of the back of the Pictor through the button on the back.
> > >
> > > While it may sound complicated (and perhaps the words can be improved with a
> > > diagram), simply trying to autocenter star and noting if the object gets
> > > closer as you change the angle will help get you setup.
> > >
> > > If you get it understood, perhaps you could provide a writeup that could be
> > > used to clarify the words in the readme file? I would suggest sharing it
> > > here on MAPUG.
> > >
> > > By the way, you can change the estimate angle at any time and the change is
> > > used for the next centering or mosaicing command.
> > >
> > > Ralph Pass
> > >
> > > M. Gartland wrote:
> > >
> > > > Help!
> > > >
> > > > Can someone please help me in clarifying the alignment for the 216xt
> > > > when guiding? The new 6.4 final version has you put in an angle for
> > > > computer guiding but it is very poorly written. Here are some
> > > > questions....It says that the writing on the camera represents the
> > > > orientation, is the button considered up (0 degrees)? If the button is
> > > > up, what angle am I measuring to? My scope is on a LXD Eq. mount, does
> > > > it matter what my scope is pointing at?
> > > >
> > > > Are we really talking about how my OTA is mounted in the cradle? In
> > > > other words......if my cradle is the orientation, then north would be
> > > > "straight up" in the cradle, and..if the OTA is mounted with the focus
> > > > lock as "straight up" in the cradle, and....the 216XT is mounted with
> > > > the button in line with the focus lock ,....then.....the angle to be
> > > > entered in pictor view in the field on view menu screen for pictor
> > > > orientation would be "0 degrees". If the button is to the "left" or at
> > > > the 9 o'clock position in relation to the OTA focus lock, then the angle
> > > > would be 90 degrees, if right, then 270 degrees, etc. etc.?
> > > > Am I correct with this? Way off base? Please put all of this into
> > > > english for me?
> > > >
> > > > Confused....
> > > > m.

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