I am looking at getting a new total station for our deformation surveys. We currently use a Trimble S6 HP 1"/1 mm, but it is now 11 years old and recently a part failed on the job so it is in the shop for repair. I would keep it as a backup or maybe use two instruments on some jobs since we shoot every point from at least two different setups. (that might not be manageable).
The S9 HP is what I would get. I asked for a quote on the most accurate model (0.5"). This model versus a similarly equipped 1" instrument costs $10,000 more. Since the majority of our observations are less than 250 m, and 0.5" at that distance is 0.6 mm, I find it hard to justify the extra cost. Of course there is part of me that wants to get the most accurate model possible.
Our survey designs rely more on the accuracy of the EDM than the angular accuracy.
I think the 0.5" would only be an advantage on longer shots, which, because of GPS are seldom done anymore.
And as you well know, just because the gun is 0.5" doesn't mean you get 0.5" results. You would have to setting up on concrete piers with sun and wind screening to really get those sort of results. That might be a possiblity in permanent automated monitoring setups, not so much in normal practice.
That is true. The fine lock is spec'd at better than 1 mm at 300 m, so it is not like we would be doing any manual pointing.
The tradeoff in the S9 line is long range DR versus high precision EDM. We definitely need the high precision EDM, but the long range DR would be nice to have for other types of surveys. I bought a Trimble M3 (non robotic) mainly for that reason in case we need a longer range DR capability. Also because it is smaller and lighter for traveling or backpacking. But we have a TX8 scanner, we use that for topo's rather than a total station (usually supplemented by a few total station shots), so the total station is mostly used for deformation surveys and some traversing.
It is amazing to me that the S6 is still going strong after 11 years. And when we do a deformation survey it gets used constantly all day. We still use the same 2006 batteries, they last a little bit less than when new, but not much. We replaced the compensators once, and now the auto focus is being replaced or repaired. Nothing else has gone wrong over 11 years.
I have a Leica T3000 (angles only) if I ever need 0.5 second capability. And a Wild T3. Probably only would ever be used for astro observations.
If you're willing to look at other brands too, ask for a quote for Leica TS60 - though it's not significant, you would get a bit better EDM accuracy.
I would certainly like to consider a Leica, but at this point I would have to get a new data collector, learn new menus, etc. Getting to be too old to change! 0.6 mm versus 0.8 mm (ISO) is probably not significant. I can't easily measure T and P to the accuracy required to get that when I am outside. Maybe inside, but not on a dam with sun, wind, etc.
As I said, I am very impressed with the longevity of the S6 that we use. I do have issues with Trimble, mainly the proprietary aspect of all of their survey equipment. As a programmer, I like to write my own software, but the details are closely guarded. I do know a lot about the .dat file format, but nothing more recent (.job, .tgd. .T02, etc).
During the 1972 presidential election I saw some graffiti that I think is appropriate (Richard "tricky dicky" Nixon was a candidate for re-election):
"Why change d*cks in the middle of a screw, vote for Nixon in '72"
So even though I am not totally happy with Trimble, it is excellent equipment, and it is what I am familiar with.
I once heard they took all the new Trimble instruments and bench tested them and based on the statistical pointing results of each instrument they divided them into 5 second guns or 1 second guns (?) I don't know if it is true or where I heard it but I always thought if I ever needed that tight of results I would just do more rounds in those instances. Jp
I had heard that as well for various manufacturers.
I actually went on a tour of the factory near Stockholm in 2008 where they make the S6. Very interesting. They also were making the GX scanner there.
The old S6 is bullet proof and the new S7 is even better. We are still using 10+ year old batteries in the S7.
The R8 batteries fail much sooner.
