GPS

[Colinlp]

How much will say a steel pier tube affect the GPS on my CPC? Will any effect be related to direct line of sight signal interference or proximity?

[Earl]

do you move about frequently to use the gear?

Once you have your coords its not of much use as most mounts remember the location anyhow, and have a few sites normally to so if your home and darksite at the most thats covered too, you can google map your locaton i belive, or even mobile phone.

[perfrej]

Just line of sight, and at your latitude the number of satellites is good. You may experience some multi-path losses from reflections, but I wouldn't worry about it.

/per

[Colinlp]

It's for an observatory pier, just some steel ducting to use as a form and the reinforcing steel.

[D4N]

It won't matter anyway as the degradation of the position due to multipath will be far less than the accuracy of the position in the first place unless you are using a differential GPS system.

If you have a modern smartphone you should find that it's A-GPS is more accurate than your standard GPS anyway. It uses the cel network to improve the position and also uses the GLONASS satellites in addition to NAVSTAR to give improved accuracy (correct for iPhone 4S and up).

Sent from my iPad using Tapatalk

[perfrej]

Just a note on AGPS... It is just for speeding up time to first fix and does nothing for accuracy. You can see it as a quick "hint" to the GNSS engine as to where it is on the planet.

As for having Glonass, and perhaps even Bei Dou and Galileo, is really more about getting reliable fixes than accuracy. In the end it is down to the mathematical model of the atmosphere in the receiver. DGPS is the most important factor for good GPS accuracy. My boat GNSS receiver, for example, has a good atmospere model and RTCM diff receiver, which taken together yield about 15 cm of accuracy most of the time and never above 0.5 m. DGPS via EGNOS/WAAS is much less efficient at improving accuracy.

If you REALLy want to know where your pier is you can employ a GNSS receiver with RTK (real-time kinematics). This will give you about half a centimetre of accuracy under normal conditions

The only reason I can think of to use anything better than an iPhone GNSS is because you really need to know the altitude - or just because it is fun...

/per