Re: Some doubts about the use of the clutch knobs on the Mach1

Joe Zeglinski

    Perhaps I can provide an example, in the “non-typical” way I make FLATS.
    I have a “permanently” installed scope – only because its a massive RC-14.5 on a Losmandy tripod, housed under a tarp rather than an observatory structure. I use my normal  “kitchen ceiling lights” illuminating a 3-foot square framed 2–sheet VELLUM target, hung “indoors”,  just fitted to the walkout glass door about 20 feet away. It is effectively just a “slats” frame with Vellum stapled to it.
    Originally, by trial & error and using a Glatter Collimator (holographic pattern) Laser,  illuminating the center of the frame, I saved the APCC corresponding ALT/AZ coordinates permanently,  in my “ALTERNATE PARK” box. So, doing flats is quick & easy – just issue an Alternate Park, shoot flats, and return to the star target or one of the AP standard 4 Parks – not unlike doing this with a Flats Target affixed to a dome wall.
       Now ... if I were able to go to a dark site, I would still keep, the same (saved) APCC ALTERNATE PARK coordinates (since I don’t want to redo them when I return).
But after a quick Polar Align at the new site, I would then,  as a final step during daylight setup,  likewise issue the (Alternate) PARK for flats, turn on the GLATTER Laser, and move (whatever portable  LED flat target, mounted on its camera tripod), into the path of the laser, and adjust the flat target height etc. to center the LED illuminated flats target on it, until it is in line  with the GLATTER collimator red laser beamed pattern, (or just the beam itself). 
    I would think my method would be a quick, easy, and accurate “field setup” for flats – no messing with slewing the mount in the field trying to center it on the flats target, which might require a bit more effort and associated lost time.
Then I would just use the (same saved ALT/AZ) Alternate Park command, as I do at home.
    Doesn’t have to be difficult. Perhaps much easier to line up the “Flats Target” to a saved  Alternate Park position, than the alternative approach of trying to establish a new ALT/AZ alternate Park, in the field, every time – as many might typically do.
    My method, in fact, does  as per your concern  ... “ guarantee that the "PARK" the mount - to point to LED panel - will always be consistent”

From: pnagy@... [ap-gto]
Sent: Sunday, August 19, 2018 5:29 PM
To: ap-gto@...
Subject: [ap-gto] Re: Some doubts about the use of the clutch knobs on the Mach1

You might want to define "semi-permanent". If the equipment is inside the observatory, then it's a good idea to "slew" to the LED panel assuming both the mount/scope and LED panel are ALWAYS fixed at the same positions.
But if the mount/scope and LED panel are somewhat portable and never fixed at same location, then there's no guarantee that the "park" the mount to point to LED panel will always be consistent.
Absolutely nothing wrong with loosening the clutches to manual point the scope to LED panel.
If you are using APCC-Pro and use pointing model and NEVER move or disturb the mount/scope and LED panel, then use the power to the mount to slew in order to preserve pointing model positions. But if it's more portable than permanent, then I wouldn't waste time trying to preserve pointing model positions and use whatever method to move or slew the scope to point to LED panel.
So, please describe what you mean by semi-permanent?

---In ap-gto@..., wrote :

I have some doubts about the correct use of the clutch knobs on the Mach1. Let me explain:


I have my mount located in my backyard on a semi-permanent basis (Park 3 position). When I have to take flats this is what I do:


(All this with the mount turned off)


- I release the clutch knobs and point my telescope at my LED panel.

- I tighten the clutch knobs again (I don't want any accidental movement).

- I take my flats.

- I release the clutch knobs and move the mount back to Park 3.

- I tighten the clutch knobs again.


Is this procedure okay or is it better to move the mount using my computer (or keypad)? I know I'm not going to damage anything, but I'm afraid it might affect the precise tracking or something.


Thank you,


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