Find a star with HMC5883

Hy I would use a HMC5883L with an arduino To aim stars.

The pb i have is To Know How can i convert the axys values To have the azimut and the declinaison

Thanks.

What accuracy are you expecting?

The HMC5883L will tell you the direction of North. You will need additional information to find stars.

Hy

Thanks for your answers.

So first, for jremington :

I need in degrees the north and declinaison position.

Second for aarg The values wil be compare with a software (Stellarium) how know where are the stars.

Stellarium give to my arduino Azimut and déclinaison The HMC give in realtime azimut and declinaison of my telescope

Arduino make the difference and correct the telescop's position in realtime with steppers.

Thanks

I don’t think this is ever going to be accurate enough to line up on a star so it’s in the viewfinder and track it (for long exposure?). Usually systems like this need lining up on certain guide stars so they can then calculate the stepper motor steps needed to point to a known point in the sky and stay there.

For tracking, other approaches are to use a webcam in the eyepiece and using image processing determine the object/earths movement and adjust steppers to keep the tracked object in the viewfinder. This usually involves a laptop but I have wondered if it could also be done using a Pixy camera and an arduino.

Riva: For tracking, other approaches are to use a webcam in the eyepiece and using image processing determine the object/earths movement and adjust steppers to keep the tracked object in the viewfinder. This usually involves a laptop but I have wondered if it could also be done using a Pixy camera and an arduino.

Could a sensor from an optical mouse used for tracking?

jperrio: Second for aarg The values wil be compare with a software (Stellarium) how know where are the stars. Stellarium give to my arduino Azimut and déclinaison The HMC give in realtime azimut and declinaison of my telescope

Great, but the accuracy is an issue. You never answered to that problem.

To locate stars, you need to know the star’s right ascension and declination, your latitude and longitude, the time of day and be able to accurately set the azimuth and altitude of the telescope.

Thanks

The Software have my altitude, Longitude and Lattitude

It give me the azimut and declinaison to go in real time

I just look for a solution to read my telescop's position.

I think that HMC 5883 can do that

I don't know how calculate North when declinaison is > 0 degrees

Thks

Whandall: Could a sensor from an optical mouse used for tracking?

Quite possibly but I have never seen or used one.

I don't know how calculate North when declinaison is > 0 degrees

What do you mean by this? The compass will tell you your [u]azimuth[/u], relative to magnetic North.

You should be using a rotary encoder for this. The only trick is finding a good mounting point for it on your telescope.

When the sensor is horizontal i havé the North but when i put an angle the value is different

Keep the sensor horizontal.

Good idea but when you look at stars you have To look the sky. So you aren't horizontal. And i would receive 2 datas. The azimuts and the declinaison.

I thought that somebody already do that

The base or platform of the telescope does not need to be tilted to look at the stars. That is where you put the compass.

You need an accelerometer to measure tilt (declination).

Thanks for this clear answer

I hoped that hmc5883l could do it