a question for GOTO owners

[jonnydreads]

hi all,  on my nexstar 8se there is a setting called custom site, I have entered my longitude and latitude this afternoon into it, I've just powered up again probably around 2 hours after I inputted it and its saved, its saved under custom site.....

now am I right in thinking that you can buy a celestron gps system for this GOTO and if so what would you need one for if you know your longitude and latitude? 

 

many thanks jon 

[Gfamily]

Hi

I don't have a Celestron, but I think it's very likely to be the case.  Not only that,  your scope will be able to get the time from the GPS unit as well. 

However, it's worth pointing out that if you have a phone with GPS capability, it takes next to no time to get the details and enter them  manually.  

As I have a SkyWatcher scope I use the  SynScanInit App - which gives me the location and  time / date in the format MY handset needs. It may work for Celestron handsets too, you'd need to check. 

Hope this helps - you can save the money and spend it on an eyepiece or similar. 

[jonnydreads]

great advice thanks 

[Cosmic Geoff]

The GPS module will be more useful if you transport the scope to a distant site, where forgetting to change the lat/long or forgetting to change it back on your return could get annoying. 

[jonnydreads]

Ye good point 

[Carbon Brush]

I think we sometimes forget the precision (or lack of) of location that we need to tell a mount.

A portable or temporary setup is bound to have small north/level setting errors. Then there are mount tracking accuracy considerations.

Then (not picking on any mount in particular) there are factors like atmospheric refraction that may, or may not be accounted for in the goto software.
I believe this can account for about 0.5deg, or a moon diameter, from zenith to horizon. The actual figure being temperature and moisture dependent.

When going to a remote site, it is usually a planned outing. This allows the lat/long to be entered before leaving home.
Many goto 'boxes' have the facility to store multiple sites.
Even if it is an unplanned stop on a car journey, your car satnav may give you a lat/long.

I can see the benefit of exactly entering lat/long, site altitude, atmospheric pressure, temperature, moisture content, if the goto kit is up to the job, and you want to time (for example) an occultation to the second to submit data for research. A lot of ifs and buts in there.

For general temporary viewing just setting the mount somewhere near is good enough.

A one degree error in long is basically asking am I in Nottingham, or in the wash? Am I in Ipswich or Cambridge?
Given that huge error represents  only 2 moon diameters, it is obvious that getting a lat/long just somewhere nearby is going to get the object in a low power eyepiece.

If you want spot on tracking at high magnification after locating a target, that is why imagers use guiding.

You may have got the impression I won't be buying a GPS add-on for a mount anytime soon!

Hope this helps, David.

[DS24]

It seems like the GPS unit would just be a waste of money because you can just simply enter in the coordinates manually by looking on your smartphone and since the GPS unit only enters it in automatically for you and not much more than that it sounds like it's a lot to spend to just not have to push a few buttons

[cletrac1922]

On ‎11‎/‎02‎/‎2019 at 03:43, Gfamily said:

Hi

I don't have a Celestron, but I think it's very likely to be the case.  Not only that,  your scope will be able to get the time from the GPS unit as well. 

However, it's worth pointing out that if you have a phone with GPS capability, it takes next to no time to get the details and enter them  manually.  

As I have a SkyWatcher scope I use the  SynScanInit App - which gives me the location and  time / date in the format MY handset needs. It may work for Celestron handsets too, you'd need to check. 

Hope this helps - you can save the money and spend it on an eyepiece or similar. 

 

I also have the SW SynScan Wi-Fi adaptor, and best thing since sliced bread

There is also a Wi-Fi unit for Celestron scopes, and the APP is called Sky Portal

Not sure if will work with the SynScan Wi-Fi adaptor

Not had a chance to try

John

 

[DS24]

I think the Wi-Fi module is for the Celestron mount not the actual scope because I often read that in descriptions and it sounds very confusing because it sounds like you plug it into the actual telescope