I have a job for panel points, they are spread out over a large area.
So I get with the people doing the flight and they want to use the local CORS station, makes sense to me.
We also agree that we will use NAVD88 and Geoid12b (those three things might not work all that well together but I didn't go into that).
It's a whole different ball game from what we used to do, only 5 panels spread out over a 25 mile corridor with two of them clustered together.
So I set up on the office base, tie into bench marks and the CORS. From the bench 2 miles west of the office to the office point it processes within .01' of record. Processing from the CORS I'm 0.10' low to the bench and .08' low to the office, pretty good and very consistent.
So I think I'll just go ahead and throw out the office file to OPUS, it comes back .19' low. HUH? How can it be any different than the result from the local CORS? After all if you adjust won't you give more weight to the point closest?
Looking at the report; OPUS didn't even use it, they used one point 150 miles south, one 130 miles NW and one I don't really know much about the third point but it looks even farther away also to the NW. The local CORS is about 5-6 miles from the office, I know the data is available on the CORS site, after all I used it. Anyway, just another reason I don't like OPUS for elevation control.
Resubmit to OPUS and request the 3 closest CORS stations you want used with extended data. Redo with the next 3 and then again. Now break your file up and resubmit several to OPUS-RS with extended data. Now consider the differences.
If it is good elevations you want your observations should be twice the minimum. I can usually meet that criteria with multiple OPUS-RS files.
Are you sure all your data is 12B?
Comparing your office processing to OPUS it is necessary to verify that all antenna parameters used are the same.
BTW, for the last few years my closest CORS is used by OPUS/OPUS-RS in only 10% of the automatic solutions.
Just because data is there does not mean it is all good. I trust OPUS to do a better data check than I do.
Paul in PA
Paul in PA, post: 451692, member: 236 wrote: Resubmit to OPUS and request the 3 closest CORS stations you want used with extended data. Redo with the next 3 and then again. Now break your file up and resubmit several to OPUS-RS with extended data. Now consider the differences.
If it is good elevations you want your observations should be twice the minimum. I can usually meet that criteria with multiple OPUS-RS files.
Are you sure all your data is 12B?
Comparing your office processing to OPUS it is necessary to verify that all antenna parameters used are the same.
BTW, for the last few years my closest CORS is used by OPUS/OPUS-RS in only 10% of the automatic solutions.
Just because data is there does not mean it is all good. I trust OPUS to do a better data check than I do.
Paul in PA
Nah
I don't need OPUS, I was just checking to see if it could come up with any kind of decent number, that didn't happen. Although, .19' is better than it used to be.
