Fieldwork was brought in for today's survey. It was in the county, but I didn't have a control point nearby, that is unusual. Kinda of a blank spot. Also didn't have any section corners within 2 miles of the section in question, also unusual. The crew chief set up, started autonomous, downloaded the base, clicked on OPUS and RTX. RTX worked flawlessly, nothing from OPUS. It was just a test for OPUS. Should be up by Thursday, that's what my inside the beltway guy is telling me. We shall see.
In my opinion you get better results from RTX
Fieldwork was brought in for today's survey. It was in the county, but I didn't have a control point nearby, that is unusual. Kinda of a blank spot. Also didn't have any section corners within 2 miles of the section in question, also unusual. The crew chief set up, started autonomous, downloaded the base, clicked on OPUS and RTX. RTX worked flawlessly, nothing from OPUS. It was just a test for OPUS. Should be up by Thursday, that's what my inside the beltway guy is telling me. We shall see.
send it off to the Trimble center point. Online processing service. I hardly see a difference between it and OPUS from same data set.
I believe that OPUS is still a GPS only service, whereas most other services use all of the GNSS constellations.
OPUS did have a GNSS subsciption and processed data using the GNSS constellation until shortly before the government shutdown.
Historic boundaries and conservation efforts.
OPUS did have a GNSS subsciption and processed data using the GNSS constellation until shortly before the government shutdown.
There has been a lot of talk about adding GNSS to CORS downloadables, and I think that some of the stations have that. But OPUS, for now, is still GPS only.
The Beta has been GNSS for at least a year.
OPUS did have a GNSS subsciption and processed data using the GNSS constellation until shortly before the government shutdown.
There has been a lot of talk about adding GNSS to CORS downloadables, and I think that some of the stations have that. But OPUS, for now, is still GPS only.
You are correct OPUS only process GPS data only even if other constellations are in the file. The Beta version as @john-hamilton states will process GNSS. And has done so for about a year now. They have just not transitioned it from BETA to the real version yet.
@olemanriver this point is moot since the government shutdown, however. there was a "beta" version of OPUS which processed GNSS data and later in the "real" version.
Historic boundaries and conservation efforts.
@olemanriver this point is moot since the government shutdown, however. there was a "beta" version of OPUS which processed GNSS data and later in the "real" version.
If that changed I didn’t catch it. The real site still states only GPS as of today. But maybe they have not updated the opus main page but who knows.
For now, actual OPUS is GPS only.
I wonder how much value adding other constellations to a 2+ hour observation brings to the table. I've always thought that a GPS L1-fixed (or iono-free for long baselines) solution was the gold standard. I haven't done any testing of this; has anyone here done any comparisons?
I wonder how much value adding other constellations to a 2+ hour observation brings to the table. I've always thought that a GPS L1-fixed (or iono-free for long baselines) solution was the gold standard. I haven't done any testing of this; has anyone here done any comparisons?
one word TIME. Each satellite has an atomic frequency standard each satellites atomic frequency standard has its own clock drifts. More satellites mor bands translates to better solving for TIME. Now that can also go the other way as we know we monitor the GPS 24/7 how well others monitor theirs is a different story we know this historically from GLONASS as it’s not as good a system globally as GPS . How well they move or relate time to one system is the other. Think of it from an historical standpoint. Latitude was always pretty easy to solve for. Longitude all revolved around TIME. Of course other things like sat geometry low says bad on horizon why solving for time. Now we can navigate by stars because we can solve for time more precisely. And accurately.
It's not because of the government shutdown... It's (GNSS model) a Beta on and off thing until it's ready for primetime. So GPS as usual.
https://rpls.com/forums/strictly-surveying/opus-beta/#post-588376
@olemanriver A nod to Albert Einstein, who without his theories of General and Specific Relativity, where the satellite's atomic clock slows down due to the speed of their orbit, while also accelerating because of low gravity, with our correcting for this, none of it would be possible.
Just because I'm paranoid, doesn't mean they aren't out to get me.
@olemanriver A nod to Albert Einstein, who without his theories of General and Specific Relativity, where the satellite's atomic clock slows down due to the speed of their orbit, while also accelerating because of low gravity, with our correcting for this, none of it would be possible.
When I was at the government I was scolded my first few weeks from those with PHD’s that using the verbiage of atomic clocks was not acceptable. lol. As I grew in knowledge and how things worked. Rubidium vs maser vs cesium on some are very precise short term some long term etc. and all the math that went into to computations to solve for all the drifts at the monitoring stations as well as the satellites themselves which all goes back to the precise ephemeris. So much information pummeled into my pea brain. I have to give credit to those men and women though they were patient with me to help me gain some understanding. I wish I had a 1/4 of the knowledge they did. Same for Einstein. Good grief some of those folks were just brilliant. I mean they had no calculator no computer no slide rule. They surely had a handle on things. I do have one thing in common with Einstein we both are dyslexic. But that’s about it.
Well you need dual frequency (atmospheric correction) for longer baselines for the highest accuracy after a few km. Sure at 5 km it's not much, at 50 km it is.
More sats are better. For those of us doing "GPS" back in the late 80's, early 90's 6 sats were good, but a lot of time 6 well distributed sats weren't available. Now with 4 Global constellations they are. Is there an improvement. Oh yea. Even NGS mentions this as a reason for a multi-constellation solution. Not so much better for a 20 hour solution in a good GNSS environment, but for 2 or 3 hours in not so good conditions? Yes. It's simple math with sat availability potential. Have I seen it over the last ~40 years? Yes.
I wonder how much value adding other constellations to a 2+ hour observation brings to the table. I've always thought that a GPS L1-fixed (or iono-free for long baselines) solution was the gold standard. I haven't done any testing of this; has anyone here done any comparisons?
I had a job one of our other offices did. The base set up was in a very questionable area. They logged about 4hrs of data. It was sent off to OPUS. OPUS could not resolve it very well at all. So I went and grabbed the rinex data from several of the CORS including the ones that were used by OPUS still not a very good solution. So next I went to the NRTK provider who had some of their stations in the NGS CORS grabbed the same data set just with full constellation data. And bam it came in quite nice. Sent the data off to Trimble center point rtx through TBC and it matched my baseline processing very well as my extra check.