Re: Meridian flip - software or firmware issue? #iEXOS-100 #ASCOM #FIRMWARE #pmc-eight

Walter Vinci

Hi Jerry,

Thanks, that should work. My understanding was that APT could automatically take care of this with a goto move if I clicked in manual meridian flip.

ps: I found that starting with the counterweight up is fine with my set up as long as I start within 1h of the meridian pass.


On May 18, 2021, at 1:25 PM, Jerry Hubbell - Explore Scientific VP Engineering <jrh@...> wrote:

On Tue, May 18, 2021 at 11:24 AM, Walter Vinci wrote:
It is nice to be able to be point a target before it passes the meridian and being already ‘flipped’ so that there is no need to interrupt imaging. 
Hi Walter,

If you want to do a Meridian flip "early" you can only do that manually, you cannot slew do this with a "goto" or point command with an ASCOM application because the goto always calculates the current side of pier of the object prior to slewing. What you have to do is:
1. Point to an object that has passed the Meridian (in the West)
2. Manually move the mount back East of the Meridian to the desired Target.
3. Start imaging as desired.

The result is that the counterweight will be above the telescope and is "up" instead of "down" which is not a standard mount state that you would normally want.
Other than that it should be fine.
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at
1010 S. 48th Street
Springdale, AR 72762

Author: Scientific Astrophotography: How Amateurs Can Generate and Use Professional Imaging Data
             Remote Observatories for Amateur Astronomers: Using High-Powered Telescopes From Home

Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
Wilderness, VA
: ES PMC-Eight G11 + Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100 ED APO CF
Cameras:  QHY174M-GPS + FW, QHY163C
Misc: 3-inch 0.7x Focal Reducer Field Flattener, Filters: Luminance,
Red, V-band Photometric, Diffuser, 200 lpmm Spectral Grating

Software: MaxIm DL 6, Cartes du Ciel, Astrometrica, AstroImageJ, AutoStakkert!


Walter Vinci

Starfield 0.8 Field Flattener/Reducer.
ZWO ASI290mm-mini & Orion 50mm Guide Scope
Canon EOS Rebel SL1
SharpCap, APT, PHD2, SiriL, Stellarium

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