I routinely use both an iPhone and an iPad running SkySafari to control my CP4 mounts, plus a few other mounts.
I have no problems with battery life. Plus, I only wake the device when I want to interact with the mount using it. After I’ve done my goto or whatever, I just put the device back to sleep. When I need it again, it resyncs automatically in about 2 seconds. I can easily observe the whole night this way and still have 90% or more battery life in the morning.
It’s possible that other software might not resync as gracefully. I’ve yet to try Luminos, for example. But the whole experience with SkySafari is seamless.
Regarding the performance of the mount, I don’t think that there is any difference in the mount’s accuracy or guiding performance going between a late version of CP3 vs CP4 – unless you have the absolute encoders. I think that the CP4 communicates much faster with the encoders than the AE controller box with a CP3. I bought my encoder equipped mount used, and upgraded to CP4 immediately. As long as I was at it, I upgraded my existing CP3 mount at the same time, so that they both run the same controller version.
Since upgrading, I find that I really appreciate the ability to connect ad-hoc to the mount’s wifi using my phone or tablet. I also appreciate being able to connect using Ethernet for controlling the mount while imaging. I’m happy that both of my mounts are using a CP4 and would do it the same way again.
From: email@example.com [mailto:firstname.lastname@example.org]
Sent: Wednesday, January 23, 2019 11:02 AM
Subject: Re: [ap-gto] GTOCP4 Control Box
... If I didn’t already have a hand controller I might have further considered the CP4 so I could use my phone or iPad to run the mount from planetarium software for visual use.
My question is, if you go to a CP4 just for this purpose, HOW LONG would your (particular) smartphone run its intended Planetarium program just to operate the AP mount, until the phone battery died, especially when severe cold drains the battery even faster?
You can operate the AP Keypad even at –20C with a “gloved hand”, but smartphones require a warm bare finger to operate its touch screen for the Planetarium program to operate the mount. I don’t think frostbitten fingers work well on smartphone screens.
Besides, there has been recent discussion on how to keep a smartphone from going to sleep after a brief interval of “user response” inactivity. I don’t think there was a good solution other than running a background program that continually pings the WiFi, as if it were a user input. I would hope that a planetarium program would do that, when you put the phone down or into a packet, while observing the skies.
Before deciding on a move to CP4, strictly for WiFi access from a smartphone app, perhaps as a “practical test”, you might want to run the intended smartphone Planetarium (display only) program outdoors on the back porch, on a cold winter’s night, and see how long the program keeps running, and how long the phone battery lasted. This would give you some idea of “real field use” under tough conditions, before you decide on a CP4, only for this purpose ... and also, whether you might actually need a new smartphone with a lower drain, longer lasting battery charge – which will probably cost as much or more than a CP4 upgrade.
However, if the smartphone works, you should still let your present AP mount Keypad tag along on field trips, just in case the smartphone dies. At least, with the Keypad as a backup, you won’t have to pack up in early.
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