<p>If the camera is accurately fixed, the declination (Dec) never changes. The only thing that changes is the Right Ascension (RA). You can get the Dec and RA from astometry.net for any photo of known date and time, then calculate the RA for another date and time by knowing the RA increases at a rate of 24 hours RA in 23 hours 56 minutes 4.091 seconds of time.</p>
<p>You can check new photos periodically on astrometry.net to make sure the camera setup is the same.</p>

CC BY-SA 4.0
2022-02-13T21:14:51.943Z
2022-02-13T21:14:51.943Z
JohnHoltz
<p>I operate a meteor camera from a fixed location with a known elevation, FOV, and I can work out its sidereal time. On a good night, it takes a large number of images of the sky (fits files).</p>
<p>I can send these to astrometry.net to find out what my camera was viewing at that time but I was wondering if there was a website that can predict what my camera be pointing at on a particular night so I can stack the images to see if I can catch the event.</p>
<p>Or is there a way of calculating what RA and dec I have at a particular time?</p>
<p>The location of the camera, which has a fixed location and elevation, is</p>
<ul>
<li>latitude: 51.07 ;  longitude: -1.34 ;</li>
</ul>
<p>The camera's field of view is ;</p>
<ul>
<li>Approx. horizontal Field-of-view in degrees fov_w: 40 ;
Approx.</li>
<li>vertical Field-of-view in degrees fov_h: 20
or approximately 150 degrees.</li>
<li>The camera's height is 87 m above sea level and has an elevation of 130 degrees from horizontal.</li>
</ul>
<p>I have some coding experience so would not be adverse to python coding if this ultimately gives a better solution.</p>
<p>The Muskegon site, <a href="http://www.stargazing.net/mas/al_az.htm" rel="nofollow noreferrer">http://www.stargazing.net/mas/al_az.htm</a>,  is comprehensive but does not provide the full solution regarding FoV and potential targets.</p>

CC BY-SA 4.0
2022-02-12T20:22:19.800Z
I understand that your camera has a fixed direction.  That is it has a fixed alt and azimuth.   Converting alt, az and time to RA, dec is a pretty standard operation. There are already answers here.  Can you confirm that your camera is fixed, relative to the ground?  Or even tell us the longitude, latitude, alt and az of the camera
James K
CC BY-SA 4.0
2022-02-12T20:23:58.267Z
Here's one calculator,  http://www.stargazing.net/mas/al_az.htm  If that doesn't do what you want, please clarify.
James K
CC BY-SA 4.0
2022-02-12T22:48:41.983Z
@JamesK OP has a bunch of images each with same alt/az but different times and dates. I think they'd like to *batch process* the times and dates to get RA/Dec values, then select a subset that might contain an event, then go back and look at those. I think a spreadsheet would be one way, the OP just needs the equation that takes alt/az/lat/lon/time/date and spits out RA/Dec values.
uhoh
CC BY-SA 4.0
2022-02-12T22:51:09.850Z
[Skyfield](https://rhodesmill.org/skyfield/) could spit out alt/az from RA/Dec/lat/lon/time/date I suppose then one can search for alt/az values that are within the camera's FOV. It all depends on the OP's preference. @ColinNichols are you interested in a Python solution?
uhoh
CC BY-SA 4.0
2022-02-12T23:54:14.123Z
There's probably a duplicate somewhere, if this is asking for alt-az to ra-dec conversion...  However I'd rather hear from the OP. They specifically ask for a "website" and so not a python solution (but perhaps python would work for them)  As you say, it depends on the OP, and them clarifying the question.
James K
CC BY-SA 4.0
2022-02-13T14:49:39.177Z
@JamesK "Or is there a way of calculating what RA and dec I have at a particular time?"
uhoh
CC BY-SA 4.0
2022-02-13T21:42:15.247Z
I've added the information in the answer to the question
James K
<amateur-observing>
Where is my camera pointing
Colin Nichols
# Where is my camera pointing

(Asked by: username_0 on 2022-02-12)

I operate a meteor camera from a fixed location with a known elevation, FOV, and I can work out its sidereal time. On a good night, it takes a large number of images of the sky (fits files).

I can send these to astrometry.net to find out what my camera was viewing at that time but I was wondering if there was a website that can predict what my camera be pointing at on a particular night so I can stack the images to see if I can catch the event.

Or is there a way of calculating what RA and dec I have at a particular time?

The location of the camera, which has a fixed location and elevation, is

* latitude: 51.07 ; longitude: -1.34 ;

The camera's field of view is ;

* Approx. horizontal Field-of-view in degrees fov\_w: 40 ;
  Approx.
* vertical Field-of-view in degrees fov\_h: 20
  or approximately 150 degrees.
* The camera's height is 87 m above sea level and has an elevation of 130 degrees from horizontal.

I have some coding experience so would not be adverse to python coding if this ultimately gives a better solution.

The Muskegon site, <http://www.stargazing.net/mas/al_az.htm>, is comprehensive but does not provide the full solution regarding FoV and potential targets.

**Tags:** amateur-observing

> **Comments:**
> **username_1**: I understand that your camera has a fixed direction.  That is it has a fixed alt and azimuth.   Converting alt, az and time to RA, dec is a pretty standard operation. There are already answers here.  Can you confirm that your camera is fixed, relative to the ground?  Or even tell us the longitude, latitude, alt and az of the camera  
> **username_1**: Here's one calculator,  http://www.stargazing.net/mas/al_az.htm  If that doesn't do what you want, please clarify.  
> **username_2**: @username_1 OP has a bunch of images each with same alt/az but different times and dates. I think they'd like to *batch process* the times and dates to get RA/Dec values, then select a subset that might contain an event, then go back and look at those. I think a spreadsheet would be one way, the OP just needs the equation that takes alt/az/lat/lon/time/date and spits out RA/Dec values.  
> **username_2**: [Skyfield](https://rhodesmill.org/skyfield/) could spit out alt/az from RA/Dec/lat/lon/time/date I suppose then one can search for alt/az values that are within the camera's FOV. It all depends on the OP's preference. @username_0 are you interested in a Python solution?  
> **username_1**: There's probably a duplicate somewhere, if this is asking for alt-az to ra-dec conversion...  However I'd rather hear from the OP. They specifically ask for a "website" and so not a python solution (but perhaps python would work for them)  As you say, it depends on the OP, and them clarifying the question.  
> **username_2**: @username_1 "Or is there a way of calculating what RA and dec I have at a particular time?"  
> **username_1**: I've added the information in the answer to the question  

---

## 1 answers

### Answer by username_3 on 2022-02-13. Score: 4

If the camera is accurately fixed, the declination (Dec) never changes. The only thing that changes is the Right Ascension (RA). You can get the Dec and RA from astometry.net for any photo of known date and time, then calculate the RA for another date and time by knowing the RA increases at a rate of 24 hours RA in 23 hours 56 minutes 4.091 seconds of time.

You can check new photos periodically on astrometry.net to make sure the camera setup is the same.


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