GPS Recommendation?

[MichaelW]

Hi, I am looking to invest in a GPS system for ground-based photogrammetry to incorporate into my Agisoft workflow and I would like to get some recommendations.

I know about the Trimble GeoExplorer, of course, and it's a heavy investment at the moment for me, but I would be very happy to get some recommendations in case there are others.

Thanks!

[Dave Martin]

Michael - I think it might help if you could give an idea of the type of environment you'll be working in and the level of accuracy you're seeking.

Dave

[MichaelW]

Hi Dave,

Generally, I am dealing with historic buildings and archaeological sites. Some are in complete condition, some are decayed severely.

I am looking for accuracy that one can obtain accurate measurements of the sites for planning. Obviously, I'd like for it to be within centimeters of accuracy but I know that's a huge investment that I do not know if I can afford at this point.

[Kiesel]

Hello Michael,

do you know these systems one in 2 m and one in 15 centimer accuracy?:

http://www.redcatch.at/3d-image-vector/

When I remember right www.geobit.es has also a system. Perhaps user/member GEOBIT can give some insights?

Karsten

[tuffi]

Are you sure that for your jobs isn't better a total station and maybe a old GPS for absolute coordinate for example Leica 530? (I know Leica system but i'm sure that you can find a good used instrument also from other company)

[ArchaeoloGIS]

I am looking into those https://emlid.com/shop/reach-rtk-kit/. For archaelogy most of the time a total station is better.

[MichaelW]

A total station would be super helpful, I agree, but unfortunately, I have neither the storage, nor time to devote to learning it fully (I only have a basic knowledge of it), whereas I am much better equipped for GPS data and GIS analysis. Because I will primarily be dealing with historic buildings and not necessarily archaeological sites, I am not as worried about the lack of a total station.

The Emlid open source hardware looks particularly interesting! I appreciate all the recommendations so far.

[frank.stremke]

hi
especialy with buildings a total station is much better since with standing wals you get all kind of problems with gps..
also you can get a used total station for a good price everywhere.
preferably one which can survey without reflector this will give you nice accuraccy and a solid workflow.
as for gps i work with the leica 530 and iam hapy with it
frank

[ArchaeoloGIS]

L1 only RTK or static will not give you any good near buildings and in urban environment. Even dual channel systems will suffer, only newest triple channel systems can probably do it in obstructed conditions. For example javad systems or newest leica gs 16/15(novatel board) and similar specs topcon or trimble. They cost a leg and liver unfortunately. For more affordable l1/l2 system google spectra precision and CHC, for ultra low cost try https://www.swiftnav.com/piksi.html. L1/L2 or L1/L2/L5 will be always better then only L1 receiver. Total stations are really cheap now, you can find second hand TS for 3000/4000$ or even cheaper and combined it with L1 static measurement for relative position. Most total stations are very easy to learn if there is basic knowledge about how they work. Most new colleges in archaeology with some basic are ready to go after first day with minimal guidance so nothing to be incommode really.