Polar Alignment Tools
I use SkEye for aligning my Star tracker (currently MSM, soon to be Star Adventurer 2i as well) and I think there are a handful of features which would make SkEye the clear choice for this style of quick phone based PA for wide field astrophotography.
1) I've added this to my Custom Catalog in the Pro version, but it would be nice to have the NCP and SCP as searchable targets in the database. One of may favourite things in SkEye is the green reticle literally pointing you to the target. Very useful for Polar Alignment.
2) Polar Alignment mode. SkEye does this to an extent already with adjustable sensor sensitivity, however across the board for Planetarium apps is that once zoomed in to the NCP/SCP for finer polar alignment the readings get real jittery and drifts around. This makes it next to impossible to fine tune alignment as you don't know which is the "real" value.
Would be GREAT if SkEye could be put into a Polar Alignment Mode where it is assumed the phone is locked off on a tripod or similar and then record sensor readings for a definable amount of time. Using something like a standard deviation function, all recorded values outside 1 standard deviation of the mean would be discarded and the mean of the remaining values parsed back to the user as the "true" value. This would mean updates would only come through every 5, 10, 30 or however many seconds the user defines as the sample period, but would still rather that than trying to align to a constantly moving target. This method could also be used to determine/advise of sensor inaccuracies. If the standard deviation is large and not falling over each subsequent sample period (effectively allowing for settle time), SkEye could inform the user of inaccurate readings and suggest zooming out to get less relative movement in their alignment target.
3) Offset Mode. The further you get from the equator, the higher in the sky the NCP & SCP get. Currently I have my phone mounted perpendicular to my Star Tracker to get alignment which makes it very hard sometimes to get down to view and control the phone. Would be awesome if there was an offset option in SkyEye so I could mount my phone horizontal to my tracker with the screen facing upwards. SkEye would effectively offset all the values coming from the sensor by 90 degrees so on the screen it would still look as though you had the phone pointed up at your target.
4) Voice command input. Zoom via volume is great, but once zoomed in a way any touching of the phone results in wild results for a few seconds. Would be great if the user could issue basic voice commands to SkEye (Zoom mainly) so there is no shake incurred by touch.
Anyway, hope you consider these. If I had to pick one it would be the Polar Alignment Mode to filter out the wonky sensor readings.
Thanks for all your efforts with this app. Big fan of it.
-
Dominic Ryan commented
Awesome, thanks so much Harsh. I have split the first 3 ideas out on their own. Left the voice control out as it sounds like it might be more trouble than it is worth.
Have also added a comment to the ZWO camera support idea for SkEye Camera;
https://skeye.uservoice.com/forums/934257-skeye-camera/suggestions/44754439-zwo-camera-support
Being able to use a dedicate guide scope here via a OTG USB cable would basically turn SkEye Camera into a serious alternative to the likes of the QHY PoleMaster.
-
AdminHarshad (Developer, SkEye) commented
Hi Dominic!
These are excellent suggestions, thanks! My thoughts:
1. NCP and SCP as targets; will do. This is very simple for me; I am just stuck behind a queue of other behind-the-scenes changes. Will get to it soon. In the meanwhile, it's great that you added them in the custom catalog.
2. I agree; it would be nice to quickly toggle between sensor settings. I assume you are aware that there are settings to reduce the jitter, but they require more clicks. I am using an algorithm that does something similar to what you described, but it's closer to an exponential moving average rather than rejecting outliers. So I guess the only change required is an easy way to toggle between the settings.
3. Yes, Indirect mode will let you mount the phone in any convenient direction, but it does require the alignment step. FWIW, the alignment is remembered for a couple of days, so it's not exactly per session.
The trouble with a fixed offset is: how are you going to ensure that the phone is exactly aligned to the intended offset. You might be able to eye-ball it to within a degree, but it won't be good enough accuracy for Polar Alignment.
The point is moot though because Magnetometers rarely give better accuracy than a degree. If you only need rough polar alignment, then yes, a fixed offset might help.However, if you need a more accurate polar alignment, please check out my other app "SkEye Cam" on the Play Store. It uses Plate Solving to provide very accurate Polar Alignment, without requiring Polaris to be visible!!
4. The Zoom by voice idea is great, though frankly, it is going to take a lot of work. Will hold on to it, nevertheless.
You might want to create separate ideas here, so that it's easier to track them.
Thanks again!
-
Dominic Ryan commented
Just noticing my Offset Mode in point three might read very much like the Indirect Mode which already exists. The difference (as I understand it) is that Indirect Mode must be setup for each session (or whenever the OTA is moved). What I am suggesting is a direct offset of live data which would not require manual setup of alignment point(s).
TL:DR
- Alignment Points for PUSHTO sky navigation
- Offset Mode for Polar Alignment while being able to have the phone screen facing upwards.