Following up my comment on using plate solving, I am setting up a new planetary telescope: Edge HD11 with an ASI462mc planetary camera and 2-3x barlow (2x used in this example). The imaging fov is miniscule - .06¡ã x .03¡ã.? Planets aren't exactly large targets either
I also wanted it to be automated from inside, so i added a 250mm guidescope?+ cmos camera and made sure I could plate solve from within sharpcap (the trick here was making sure the settings were correct and do about 20 second exposures). I made sure the fov of the guidescope was large enough so that I didn't have to precisely align the guidescope and main telescope.
Using this approach I was able to goto, plate solve, and find jupiter, saturn, and (with a little more work) Mars within the tiny fov.?
I could have just as easily swapped out the 462mc sensor with an eyepiece and taken pretty much the same approach. So that could?be a bit of a hybrid plate solve/visual observing kind of thing.?
If there's interest, i can get some more pics/writeup of this approach and setup.
Note that seeing was pretty bad last night, so my jupiter is not good. But i wanted to grab the time to test this idea
?
Dereck,
6 arc minutes is a tiny FOV, I would align with a lower power eyepiece
and then swap if for a higher power.
?
That¡¯s
what I said in the post you responded to! It says..
***
I used a camera and changed the Region of
interest.. If you use eyepieces, like I used to do, start out widefield until
you locate the target, then increase the power ¨C i.e take the time to be exact
as possible before adding them to the model..
***
I
use the camera as a set of eyepieces, locating the target at around 3,000 x
2000 pixels, center on the crosshairs, change the Region of Interest to 640x480
and center better, then synch and align.. It was after the third star was
entered into the model ¨C from my 6 arcminute Region Of Interest Camera view -
that I just happened to do a GOTO back to all three model stars ¨C without changing
back to the full 3,000 x 2,000 pixels - that I was SHOCKED they were all
perfect.. Sorry that wasn¡¯t clear..
??? HOWEVER!
When I tried it again last night, It worked perfect for the first star..
Arcturus was in the (widefield ROI) of the camera.. A GOTO to Antares was not,
but it was in the guidescope, so easily centered and synched on..
??? My
(widefield ROI) is somewhere around 20 arcminutes, so it SEEMED it was another ¡°it
stopped short by a half moon diameter / 15 arcmin¡±.. It is this ¡°works one day
but not the next¡± issue why it is ¨C to me ¨C much more important to have proper
pointing devices and adequate scale between them so even if things are perfect,
it¡¯s a very simple matter to get back on target and continue on..
??? Derek
?
?
?
(I
had to calculate my FOV.. It is listed as 0.1 x 0.07 degrees, so 6 arcminutes..)
This
may include an extra step or so, as I was always told not to align on the first
star.. Anywho, this is what I just did.. Maybe it¡¯ll work for you!
My settings are correct.. I have a new battery, I
reset CWD. I did a cold start.. My clock runs very fast, so I use my cellphone
and set it to the second and hit the SET button when appropriate.. I do this on
every powerup.. I live in?Morgan Hill,?CA?and this was around 8:30 PM.. aka a
little while ago..?
I did a goto to Arcturus. Laser should it as it
normally is, which is HALF a moon diameter away, almost entirely in RA.. (I use
the tactile buttons on the back on the hand controller.. Coiled cord points
away from me.. The button is what I need to center the target.. Also takes just
a touch north in Dec.. I mention this for the ¡°Stops Short¡± idea.. )..
Anywho, I centered Arcturus, and SYNCHED..?
GOTO
Antares, Center.. SYNCH.. ALIGN..?
GOTO
Arcturus.. Centered it, as it was off towards the top left, and ALIGNED..?
GOTO
Vindemiatrix and it is nowhere to be found and I didn¡¯t try! I did a Goto to
Arcturus.. On the way, I saw Vindemiatrix flash by.. *Importantly* Arcturus was
in the same top left corner it was previously, so I went to MENU / ALIGN / UNDO
LAST ALIGNMENT.. This time I centered Arcturus, SYNCH, then ALIGN..?
GOTO
Vindemiatrix, Center SYNCH, then ALIGN..?
Arcturus to Vindemiatrix is around 20 degrees..
Arcturus to Antares is ~ 56 degees.. Antares to Vindemiatrix is ~ 62 degrees..
Not the best choices, but good enough.. Now I have three stars in a model on
the West. And?regardless of which order I went to
them via GOTO, they were all quite close to being centered in my little 6
arcminute FOV.. My guess is they were all within 2 arcminutes of being perfect..
I used a camera and changed the Region of
interest.. If you use eyepieces, like I used to do, start out widefield until
you locate the target, then increase the power ¨C i.e take the time to be exact
as possible before adding them to the model.. and remember, SYNCH, then ALIGN..
The ¡°New¡± thing for me was to try and go back to previous stars to make sure
they were correct before adding another one, as if it is wrong in any way, you
can ¡°UNDO LAST ALIGNMENT¡±..?
I parked it at CWD and will do a WARM RESTART and
see how it works next time out.. :-))
Put
the Counterweight bar horizontal , use the clutch knob as needed, and level
with a torpedo level.. Spin the RA dial and set it to something like 18 hours..
Loosen clutch and lower the Counterweight bar and set it at 0 hours.. Lock the
clutch.. Loosen the other clutch and adjust the scope until the level on the
dovetail is centered.. Tighten clutch.. Your visual, so do this ¡°well¡± but do
not obsess with it.. I have a solution for you to try.. Just worked perfectly
for me.. First time and I am quite pleased about it!
See
next email.. It¡¯ll take a minute..
Agreed about ¡°should.¡±???
What is the best method for making sure I have CWD a good
as possible?
Assuming you are polar aligned it is not just the CWD
position that matters but the top of the dovetail should also be levelled, both
with a small level.
This is easy and quick and should get you fairly close.
Then centre the star and synchronise the first star.
If you are not so closely polar aligned then take the time
to do alignments on three or more stars spread across the sky.
This sill build a pretty accurate model and no camera is
required.
It will need to be rebuilt if you move the mount, but
should only require a synchronisation if you only warm start.
?
On 7 Aug 2022, at 8:41:23 am, Mark de Regt <deregt@...>
wrote:
I really appreciate all the suggstions!
Two things have resonated:
- I only guestimate CWD
position with my eye.? If precision of CWD matters, and if there is a
simple way to get it perfect, that may be the cause.
- People keep taking about
using plate-solve to work around the poorly-functioning Gemini2 model
building.
- I need a
camera to do that; I¡¯m happy to buy a cheap camera for that, but not an
expensive one; any suggestions?
- I own
TheSkyX Professional Edition, a very powerful planetarium program.?
Would this do that is being suggested, and, if so, how?
?
-- Brian?
Brian Valente astro portfolio? portfolio astrobin?
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