In the process of learning the limitations of the S6. Phenomenal gun I have to say, but like everything, it's has it's limitations. Today was fairly warm for Alaska, in the mid to high 70's, bit of heat shimmer, our back sight was out about 1600'. We had the gun set on Autolock for the back sight prism (a 62mm SECO) when it started jumping all over the place, lock, no lock, lock, no lock, bouncing around up and down. Couldn't measure rounds to a fly point for making a critical tie so had to bag it for the day. I talked with the dealer rep who said we were right on the edge of the range for a passive prism. I occasionally need to make shots considerably longer. Anyone know what the solution is? I'm using a multitrack on the rod, but do I need to look into another multitrack (or other active prism) for the backsight? Suggestions?
Thanks in advance. Cheers! Willy.
We used the same 360 prism for front and back sights. I mean the same physical one.
I don't know for sure but we got a 1300' shot one day trying to save another setup and we got a little talking to back at the office about pushing our luck with a shot that long. Being new to the S6 I asked about distance shots and was told we were pushing it at 1300'. That was probably 6 summers ago and VERY hot that week - around 105(f) for several days. Rare for these parts.
No one showed me any specs on reliable distance shots. I'm just passing on what I was told.
For comparison, my Leica TCRA1102plus had some trouble one 100° day locking onto a standard 62mm backsight a half-mile away. It eventually got the shot, but it took half a minute or so to lock. On cooler days half a mile isn't a problem for a 62mm backsight, and I routinely go 1500 feet to a miniprism backsight.
Tracking a moving prism at half a mile would be harder, and probably not worth the effort.
Just turn off autolock - you can go way further to the same prism with manual
I agree with Jim; just turn off Autolock. Here in South Louisiana the humidity and heat shimmer make anything over about 1200' pretty tough. I was running a traverse last winter with a backsight that was 2,176' and had to turn Autolock off; it's been my experience that 1400' - 1600' is typically about the limit.
We use the S3 here in Texas, we have heat waves here year round so forget 1600' shots, but as two above me said, no autolock. We have found, even using the Trimble Multitrack prism that autolock causes a lot of issues at a distance. Good luck!
The "lock - no lock" thing has happened to me as well. Maddening, isn't it? Turned the gun in to servicing and they said the laser was out of adjustment. When the gun was returned I didn't have any more trouble like that. ::shrug::
> Just turn off autolock
That works great, unless you're running robotic and need to turn sets to the rover, which is my normal mode of operation.
Only problem with turning off the Autolock is it makes turning rounds (doubling angles) a bit dicey when the gun can't lock onto the backsight. I did take a number of shots with it off, including one that turned out to be 0.8' off, making me not trust it for control type stuff. I've got my personal Topcon gun in the truck and I think I may just need to break it out for this kind of situation, just blows if I'm working solo.
Zapper, gun is brand new. It darn well better not have the laser out of alignment already. I'm going back out to see if making the long shots in cool of morning makes any difference. Was curious if using another multitrack prism for the back sight would be a potential solution or just a waste of money. (BigE, I'm not running the same physical prism back and forth if I read that right! ;-))
Thanks for replies and TGIF.
Willy out.
I wouldn't use the active prism as a backsight, 360 prisms have pointing error. In fact, for control, I wouldn't use a 360 prism for the backsight OR foresight.
If you turn rounds (automated rounds, that is) and sight the backsight with Autolock off, the instrument will stop on the backsight every time and the data collector will prompt you to check the pointing.
There's no way an S6 should ever have 0.8' error in a control point; I've turned hundreds of angle sets with them and they're always smack on.
To clarify Lee it was a topo sideshot and not rounds. It occurred when I first started having trouble with autolock on the back sight. I was checking into and old point and missed by enough to make me want to reshoot it.
Gotcha. It's easy to field calibrate the tilt sensor, Hz collimation and V indexing, and tracker collimation, just set up a prism with a target plate at 300' or so. I don't recommend trying to do the trunnion axis tilt yourself though, leave that one to the service guys. If the Autolock collimation is out you'll see error like that.
