96 replies to this topic

[myzsot]

My biggest problem during an imaging session was the guiding. Not having an autoguider, I was stuck with my laptop and it's limited battery life. My goal was to replace the laptop with something which is not as expensive as an autoguider but it can easily do what an autoguider does (usually this means guiding and DSLR control). The iAstroHub is a great project but what I saw from the screenshots is that you need a quite big screen for the web interface and I wanted to run the whole thing on my phone's quite small screen (compared to a tablet). 

So I started developing StarsPi, a dedicated Android application which is capable to communicate with a Raspberry Pi via WiFi. The Pi runs a modified version of Lin Guider which is accepting commands and transfers the results to the application. The benefit of a dedicated application is that the UI can be designed much better and intuitive also for smaller screens making possible to install it on a handset. To keep it short: StarsPi is a user interface towards Lin Guider which is running on the Pi.

What is working right now:

- transfer the image on WiFi, in two different sizes: VGA(640x480) and QVGA(320x240). The image format is selected dynamically by the application depending on your connection speed. This is necessary to keep the 1FPS on lower-end devices

- select the guide star on the image using simple touch gestures

- setting the exposure and gain values for the camera

What I want to implement:

- whole calibration process

- guiding with real time data representation (RA and DEC drift)

- DSLR control

- dithering

- notifications on important events: guide start lost, drift above threshold etc.

 

Right now I'm working on the implementation of the calibration process: the dark and the reticle calibration (the UI is already available in the app)

 

I'm seeking feedback from you, what do you think about the idea? Is it something you would use as an alternative instead of a laptop or an autoguider?

Do you have some ideas I can incorporate in the future? 

 

Thanks in advance!

 

PS: two screenshots attached.

 

 

. 

[ccs_hello]

Hi,

 

Interesting project.

 

Questions:

 

1. How does StarsPi connect to the guidecam (which imager you are using) and does the RaspPi handle the traffic well (e.g., high-speed USB 2.0 at BULK transfer mode)?

2. Do you plan to use RaspPi 2, RK3188T based TV stick, or other devices (e.g., the $35 Odroid C1)?

 

Clear Skies!

 

ccs_hello

[Gilles30]

Really nice project...

 

Waiting for the release :-)!

 

If you need beta testers, I'm here!

[myzsot]

Hi,

 

1.) The camera I'm using is a QHY5L IIc, the screenshot contains the image of the so called null_camera (for testing purposes). The camera<->Pi connection is not an issue, however the CPU load increases to ~30% when the VGA sized image is transferred.

2.) So far no plans to upgrade the HW. The Pi2 has two major benefits from my point of view: better CPU and more USB ports. My feeling is that the CPU will not be a bottleneck (we'll see). The added ports will not help as I'm using devices which are drawing quite a lot from the supply lines(WiFi dongle, camera), a powered USB hub is much better in this case.

About portability: if your chosen device can run (the modified)Lin Guider, has WiFi connection and at least a USB port for your camera, you are good to go!

 

[myzsot]

Really nice project...

 

Waiting for the release :-)!

 

If you need beta testers, I'm here!

Thanks Gilles30, that would help a lot. I have only two handsets for testing, it would be great to see how it behaves on other devices.

I will post the updates in this topic.

Edited by myzsot, 08 March 2015 - 12:26 PM.

[anat]

That is cool. Count me in for betatesting  I have only a nexus 7.

 

Anat

Edited by anat, 09 March 2015 - 01:06 AM.

[Gilles30]

I can test on several devices :

- sony Xperia Z

- Acer TF300T (tablet with keyboard)

- Samsung S4

- Wiko Birdy

- Samsung S2

 

If you want I test something, send me a private message.

 

See you soon.

Edited by Gilles30, 09 March 2015 - 02:31 AM.

[myzsot]

In order to distribute beta versions of an app I need to add you guys to a group, to download the app from the Play Store. Please pm me your gmail address if you want to test/play with the app.

Thanks.

[myzsot]

The application was submitted to the Play Store. As soon as it is available, it can be downloaded by anybody who joined the Google group created for testing.

I will create a description how to configure your Raspberry Pi to get the things working. Stay tuned...

 

EDIT: you can acces my blog at https://starspi.word...tegory/starspi/

Edited by myzsot, 09 March 2015 - 01:18 PM.

[myzsot]

I managed to migrate the existing functionalities into the new version of Lin-guider v.3.0. This version comes with better camera support, which extends the usability of the overall project.

Based on the forum comments and some reasearch on the net, I decided to upgrade the HW too: it will run on RPi 2. It will eliminate the need of a powered USB hub, so things will get simpler.

[myzsot]

Update:

StarsPi is running on Raspberry 2. It took a while because I changed the WiFi dongle to another one. The CPU usage is around 5% when transferring full (640x480) live view images (also the download speed increased). Changing the HW was a good idea guys, thanks!

I will keep you updated about the new features!

[myzsot]

Hi guys,

 

Here is a short video showing some of the functionalities already working.

I would really like to hear your opinions, please feel free to comment!

https://youtu.be/LdixWMUyZU0

[myzsot]

The first public version of StarsPi is available on the Play Store: link

You can find the installation instructions on my blog here.

Looking forward to hearing your opinion!

[sampson]

The first public version of StarsPi is available on the Play Store: link

You can find the installation instructions on my blog here.

Looking forward to hearing your opinion!

 

Hi Zsolt Nagy,

Thank you very much for your effort !!!!

 

I have tried to install the modified Lin guider using your installation script. However, the script fail to find my Edimax EW-7811Un wifi dongle with RTL8188CUS chip and the process was stopped. I tried to delete the scripts (line 1 to line 8) of the "setup ap.sh" and run it again. Everthing was fine then and I got it work. My phone is LG Optimus.

 

It would be appreciated if the SSID and Pass could be changed in order to avoid confusion if two or more persons who were using your app nearby. It is very common that more than 5 persons get together for AP activity at same spot in Hong Kong.

 

Please forgive my poor English as I am a Chinese from Hong Kong.

 

Thanks again !

Edited by sampson, 02 June 2015 - 01:22 PM.

[patdut63fromFr]

Hello Myzsot,

 

First of all, your app is nice and i commend you work. I love the idea to have guiding capabilities on nomad devices and a nice and homogen app. This would be great if you add control on camera and astrometry capacities on different tabs. But if you do that you will recreate iAstrohub.

So just a simple remark: why not working with Anat to build an Android App that would be part of iAstrohub instead of its current embedded html client ?

 

Patrick

[myzsot]

Hi sampson!

 

Thanks for the kind words.

To answer your questions: there is a file called hostapd.conf in the folder where the scripts are located. There you have two lines:

- ssid=StarsPi

- wpa_passphrase=raspberry

 

The script is copying this file to the correct location so if you change it here, it will applied as your settings.

Clear skies!

 

 

The first public version of StarsPi is available on the Play Store: link

You can find the installation instructions on my blog here.

Looking forward to hearing your opinion!

 

Hi Zsolt Nagy,

Thank you very much for your effort !!!!

 

I have tried to install the modified Lin guider using your installation script. However, the script fail to find my Edimax EW-7811Un wifi dongle with RTL8188CUS chip and the process was stopped. I tried to delete the scripts (line 1 to line 8) of the "setup ap.sh" and run it again. Everthing was fine then and I got it work. My phone is LG Optimus.

 

It would be appreciated if the SSID and Pass could be changed in order to avoid confusion if two or more persons who were using your app nearby. It is very common that more than 5 persons get together for AP activity at same spot in Hong Kong.

 

Please forgive my poor English as I am a Chinese from Hong Kong.

 

Thanks again !

 

[tango13]

Hi Zsolt,

 

congratulations on your awesome project, really well done!

I'll follow its developments with great interest.

 

Thank you very much.

 

Ciao,

Piero

[myzsot]

Hi Patrick,

I understand your point of view, however the two projects are quite different in my opinion:
- iAstroHub is a complete solution with a lot of integrated functionalities
- StarsPi was mainly created to be an alternative for an expensive autoguider

The next version will contain DSLR control and dithering functionalities which means it will have all the necessary functionalities for an autoguider.

Hope you will like it!

 

Hello Myzsot,

 

First of all, your app is nice and i commend you work. I love the idea to have guiding capabilities on nomad devices and a nice and homogen app. This would be great if you add control on camera and astrometry capacities on different tabs. But if you do that you will recreate iAstrohub.

So just a simple remark: why not working with Anat to build an Android App that would be part of iAstrohub instead of its current embedded html client ?

 

Patrick

[myzsot]

Hi Piero,

 

I'm glad you like it!

The next version will come with some goodies like DSLR control and dithering as I mentioned before.

Ideas of improvement, of course, are welcome!

 

Hi Zsolt,

 

congratulations on your awesome project, really well done!

I'll follow its developments with great interest.

 

Thank you very much.

 

Ciao,

Piero

[Husbyggarn]

Very interesting! I'd rather have a pi out by the mount all night than a whole laptop.

DSLR control? do you mean AP functions like live-view, timer, settings, etc?

Since i don't have goto i use plate solving to center the targets, i wonder how fast/slow plate solving would be on a pi2...

[myzsot]

Hi Husbyggarn,

 

DSLR control will be remote shutter control in the first phase: this means you can set the number of frames, the exposure length, the pause between them and the ISO of course. The live view will be much trickier, I thought about a shoot and download system to help you in the framing and focusing. Another idea would be an additional button which temporarily sets the highest ISO value, 30 sec exposure and shoot. We can call it frame and focus button or fast preview etc.After you have the 30 sec frame it will download on the phone and revert to your original settings which you normally use for taking pictures...

As I mentioned before, this project was mainly built for replacing the expensive standalone guiders. I'm not planning in the near future to introduce plate solving as a functionality. I hope you will still try it and enjoy its features!

Very interesting! I'd rather have a pi out by the mount all night than a whole laptop.

DSLR control? do you mean AP functions like live-view, timer, settings, etc?

Since i don't have goto i use plate solving to center the targets, i wonder how fast/slow plate solving would be on a pi2...

[Husbyggarn]

 

Hi Husbyggarn,

....

 

Thanks for your answer!

Understood!

Live view and plate solving is not needed when the camera just snaps photos all night long and i see the benefit if a rpi could handle the guiding and dslr schedule instead of a laptop.

[sampson]

Hi Zsolt,

I found that the lin guider would restore the default setting after rebooting the pi. I have to input all the parameters again after starting up the system. 

I don't know whether I am the only person having such problem. 

[myzsot]

Hi Sampson!

 

No, this is not your fault, I need to update the lin_guider package: when you hit the shut down command the settings are triggered to be written on the disk, afterwards the Pi shuts down. I did some bad programming there so the file is not written on the disk, that's why you loose the settings. I did correct this on my local version but forgot to put it on the drive. I will post it asap and leave a comment when it's done.

 

Btw, did you have any problem with the guiding performance?

[sampson]

Hi Sampson!

 

No, this is not your fault, I need to update the lin_guider package: when you hit the shut down command the settings are triggered to be written on the disk, afterwards the Pi shuts down. I did some bad programming there so the file is not written on the disk, that's why you loose the settings. I did correct this on my local version but forgot to put it on the drive. I will post it asap and leave a comment when it's done.

 

Btw, did you have any problem with the guiding performance?

Hi Zsolt,

Thank you for your reply. I am just a newbie for AP and have never used guiding program  . I 've just started to learn autoguiding and I wanted autoguiding with a light and little device since I don't have a car. Raspberry Pi would be the best and cheapest solution for me 

I am sorry that I have not yet to test StarsPi since the setting would be lost after rebooting the system and there is no way to reset the driver in the field. I have tried to install x11vnc for trouble shooting in the field but the vnc server can not be connected after installing StarsPi   .

 

I have many questions about guiding and I need to learn. Here might not be a good place for me to ask silly questions about autoguiding  . BTW, you have done a good job 

 

Sampson

Edited by sampson, 26 June 2015 - 10:30 PM.