MarcK guide scale calculators also exist at that website. A less than 5 to 1 is a typical ratio for scope resolution to guide scope resolution . My 644 scope guides with a 240mm guide scope so it is basically 2.5-1 after calculating the individual resolutions. The smaller the guide scope resolution the better the guiding. I use a 240mm guide scope with my 2.9uM pixel guide camera and it works great. It will be way better than a 120mm guide scope with a guide camera with 3.75uM pixels as the resolution is better on the 240 combo. OAG’s work great sometimes because a 644mm scope using 2.9uM pixel resolution would be even smaller and have small tight star centroids to guide on at the increased focal length. That is kinda the typical jist of it. Guiding does not care about your imaging scope that much. It just cannot be a 120mm guide scope used on a 2000mm imaging rig. It needs to be about 3-1 to be in a sweetspot or lower. As your guide scope setup resolution gets bigger then your guiding accuracy gets lower due to centroid estimation error. It is nice to get it below 4 but the higher the focal length requires it to get even smaller. My 644mm imaging scope has a resolution of 1.2” and the max I want my guide scope is 3.6” as 3 to 1 is ideal… but 3” (2.5-1) is where Iam now and it is a bit better.

My rig has a choice of three cameras - a main camera (3,000mm focal length), a guide camera, and a wider-field "finder" camera.

At present I have to manually select the "finder" camera as the MAIN camera to do the polar alignment, and then GOTO and plate-solve. I then manually select the real "main" camera to start imaging at 3000mm.

Would it be possible to add pull-down menus to choose a specific camera for the plate solve function, and and a pull-down menu to choose a camera for the polar alignment, instead of always using the main camera, and have those settings remembered for the evening ?

Tech@ZWO Please make sure we can enter any value that is between a reasonable range. I do not want that we can choose only 0.1 or 0.2
While you are at it, being able to enter a value for guide camera exposure would be great. The 0.5, 1, 2, 3 is too limited.

When I "goto" the Android ASIAIR App for photo data that I took in the past, the menu asking for angle-of-view check and adjustment does not appear. Many Android users seem to be experiencing the same problem at the moment. Please check. ASI533, even though the angle of view of the previous photo and the current photo is slightly different, it is not recognized.

@Tech@ZWO any update about this issue https://bbs.zwoastro.com/d/17089-asiair-v212-public-beta-released/203 please? I was trying to cut a ticket, to post on the forum, but there is no update. A help can be appreciated.
Thank you

It looks like things are changing for the better. Minmo default has been reset to 0.1 and a new added advanced tab with a few new options. Other new items such as mount input voltage is useful to know. Not sure yet how corrected trigger accuracy applies and is it just a simplified adjustability for minmo?

Kevin_A I had just never heard of the term corrected trigger accuracy.

MinMove is just a limit (e.g., 0.1 pixel) where no correction feedback is sent to the mount if the centroid did not move by no more than that (e.g. 0.1 pixel).

A MinMo of 0.2 pixels would require the measured centroid to move by more than 0.2 pixels before there is anything fed back. I never liked the concept of limits in a feedback loop (derogatorily nicknamed "bang-bang control" by those in the business) and prefer a purely linear loop (MinMo of 0.0) since it more mathematically correct.

With a MinMo of 0.2 pixels, a high PE slope mount would have moved by 0.4 or more pixels before any correction is sent to it (check the sawtooth graphs). More likely 1 or two pixels. ZWO is using 0.2 pixels probably because their mounts are not linear to within 0.1 pixel (you get what you pay for).

https://www.techtarget.com/whatis/definition/bang-bang-control#:~:text=Bang%2Dbang%20control%20is%20a,(setpoint)%20has%20been%20reached.

Chen

w7ay zwo have now released the latest testflight and defaulted minmo back to 0.1px as it made our guiding worse when it was at 0.2
I’m I have been pestering them now for months to put it back.

Kevin_A I have been pestering them now for months to put it back.

Completely random "techincal" activities over there.

When ASIAIR first started ueing PHD2 for auto guiding, it was using a 0.2 pixel MinMo.

When I acquired my first RST-135, I wrote and told Sam that a Harmonic drive that has no backlash needs smaller MinMo to work well. It took at least two years of pleading (and only after they had started "designing" the ZWO mounts) that they finally relented, and changed it to 0.1 pixel; presumably, as you found out, 0.2 pixels is a disaster for these gears.

Now some random person with no Control Theory background decided to change it back to 0.2 pixels again in an early TestFlight.

Finally, they appear to now allow 0.1 pixel again.

What a zoo.

Chen

w7ay yes, it took a few logs from myself and others to show them the differences. I think that they may have had oscillating issues with a few 432s mounts that settled down and were kind of fixed using 0.2, but now all their mounts are 288s and may not have issues with oscillating so they are back to 0.1px. I am just glad it is back to 0.1px. Who knows….
I think that they care more right now about the Seestar thingy anyways. I havent seen clear skies in 6 weeks now so nothing matters to me right now. All I am doing is getting prepared for when the skies do clear…. Better guide scope, better ways of elliminating flexture, better guide settings and better mount rigidity etc.

w7ay mine actually defaulted to 0.2 when I installed it.
I cannot test now anyways due to clouds clouds clouds. 6 weeks and counting.
I cannot even test my new guide scope w/ flattener with my 290mm mini due to 100% clouds.
Bad weather this winter for sure.

@Tech@ZWO Please we need help on this one https://bbs.zwoastro.com/d/17089-asiair-v212-public-beta-released/203 any answer can be appreciable
@Kevin_A there is any way to do a quick escalation i feel like it's not working to ping them

caradou are you using the testflight version. If not, do so and send feedback through the app regarding the issue. Keep it simple in your request… not overly detailed. I had issues previously with a dslr being recognized but it was the way I was tryin* to access it after starting asiair. Make sure the camera has BOTH data ucable to asiair usb port and snap cable( intervalometer cable ) to snap port attached with the camera turned on prior to booting up asiair. It needed both cables on my Nikon for my camera to work. Make sure your camera is on M in Bulb mode too.