Automated Meridian Flip (AMF)

The SessionCraft is accessible from Tools tab
or with F9 key.
Related videos:
Session Craft is designed to monitor various events and to control imaging session. It works even when the window is closed. The first feature from this tool is "Automated Meridian Flip" (AMF). APT can be configured to track the object position during the imaging and when it closes the celestial meridian passing to flip telescope position to prevent physical damage or bad guiding. After that flip the imaging process continues from the interruption moment, aiming to the exact same place of the sky.
To achieve this goal of Automated and Unattended Meridian Flip (AMF), APT follows the next scenario:
1. If there is running plan, before every exposure is checked if there is enough time take a new image before the need to make flip. If there is no running plan the check is running in real-time
2. If the "Flip Moment" occurs or there is no enough time to take another exposure, Session Craft determines the exact position of the current target via PointCraft taking a short exposure
3. Pauses for user defined time, disables the tracking and guiding giving time the object to pass the meridian or the scope position to be safe after flipping the pier/tripod side
4. Once pause is elapsed, it enables the tracking and flips the scope position
5. Makes GoTo++ to the target in order to frame the object by the very same way as before the flip
6. Enables the guiding by selecting a new guiding star and making re-calibration if needed
7. Resumes the imaging plan
Because these operations could be dangerous for your setup, in case of smallest problem for security reasons APT leaves the scope with disabled tracking, disabled guiding and stops the imaging plan. In every moment you can press the Stop button in Session Craft, the Stop button in Gear Tab or by pressing F12 key to stop all movements and actions.
The default Meridian Flip settings should work out of the box for virtually every setup. It will stop 5 minutes before the celestial meridian passing, will wait 5 minutes after the actual passing through the meridian (total pause of 10 minutes) and after that will flip the scope position. Every step of the process is logged in the Log panel. During the flip the SessionCraft windows will be displayed automatically if it was closed.
However you must to prepare your setup, learn its behavior and observe the first few flips to be sure that everything is fine and safe. We do provide the automation, but you are using it by your own decision and you are taking the whole care for your scope! Keep eye on your setup during the first few flips!!!
Here are the most important checks to make before enabling Make Automatic Flip:
1. After preparing your setup and connecting all cables make "dry" manual flips moving the scope by hand from the both sides of the pier/tripod to make sure that all cables are free. Make these checks near the Zenith, but also above South and North points of horizon. It is very important! Short cables or short cable travel can cause serious damages to connectors, ports or to pull computer form table!!!
2. If you are using CCD/CMOS and usually there is needing Histogram stretching in order to solve the images keep the Histogram open.
3. Make sure that you have configured PointCraft correctly. It is used to determine the exact position before the flip and to reach the same position after the flip. We suggest to configure both PS2 and ASPS and for the first flips to use blind solving for target centering. We also suggest to define Default exposure in PointCraft Settings which is long enough to get few stars with all of your filters. If defined by Blind solving ASPS will be used only for the first step of the GoTo++
4. Check the usual time PS2 takes to solve an image from your scope. If it is more that 1-2 minutes increase the Flip Moment.
5. Make sure that you are using PHD2 or MGen2/3 for guiding and that Control Guiding is enabled. Meridian flip is also possible when your mount doesn't need guiding.
6. Make sure that you are using dark frames in PHD2 to avoid selection of hot pixels during guiding star auto-selection.
7. It is advisable to confirm the limits of your setup. Once the scope is aligned move it to position East from celestial meridian near Zenith via the handset, control panel of your driver or Gear Tab. Start making fine movements towards meridian and keep an eye on Meridian Flip Clock. See if the default limit of 5 minutes before meridian passing is safe for your kit. If not increase Flip Moment to a value that fits better. Move the scope from the other side of the tripod/pier and close it to meridian. Meridian Flip Clock will show values close to 720 minutes (this is the time of next meridian passing - the lowest object position). If the position that shows 715 is not safe see the value that fits better and subtract it from 720, set the result as Delay Flip Move. For example if the safe position is 713 minutes the needed delay is 720-713 = 7 minutes.
The points 1 and 2 have to be checked on every session. The other point are needed in the first time or after scope change. You can skip point 7 only if you are trying the default settings and you are keeping an eye on the process!!!
Note: If AMF happens during execution of Flat, Bias, Dark or Dark Flat plan APT will stop the tracking and guiding and will continue with the imaging plan.
Note: Some mounts/drivers support command to change the scope side according the tripod/pier side. If the execution of this command fails enable the option Flip via GoTo.
Tips & Tricks:  If you are using EQMOD check this very useful article written by Jim Hunt - https://aptforum.com/phpbb/viewtopic.php?f=19&t=5101
Automated Meridian Flip (AMF)

Make Automatic Flip

1. Make Automatic Flip
Enables/Disables making the automatic meridian flip (AMF). On enabling SessionCraft will check the flip settings and will give an error message in case of problem. Once you enable this option APT will check all the required parameters for unsupported combinations.
When AMF is enabled a small blinking indicator will be displayed in the upper left corner of the Status panel to show that SessionCraft is monitoring when flip has to be made.

Meridian Flip Settings

2. Meridian Flip Settings
Opens the Meridian Flip Settings dialog box.


3. Status
This area show the Session Craft status. If Make Automatic Flip is unchecked Session Craft will not make any actions. During the flip process it shows the current step or the remaining time of pause defined by Delay Flip Move.
- When Flip Moment is positive the status will show count down counter from 3xDelay Flip minutes before the flip moment
- When Flip Moment is negative the status will show count down counter after the meridian passing till the flip moment

Flip / Stop / Reset

4. Flip / Stop / Reset
When Session Craft is in "Monitoring" status you can use the Flip button to start the process manually.
If automatic meridian flip is in progress this button becomes Stop that will immediately stop all movements, tracking, guiding, solving and imaging.
If the last automatic meridian flip process failed or Stop button is clicked this button becomes Reset that can clear all errors and flip process can be restarted. Note that you will have to start the scope tracking manually by Tracking in Gear Tab.