I've been reviewing this thread on using a digital level:
https://surveyorconnect.com/index.php?mode=thread&id=293219
Forgive me if this is a dumb question, but:
Is a total station a legitimate substitute for a digital level, as long as the vertical datum is checked and set to zero?
Nothing like a digital level. It doesn't read the codes on a bar-code rod like a digital level.
But it can be a reasonable substitute for a plain old automatic level if you take the average of both faces.
rfc, Seeking Enough Knowledge To Be Dangerous
It is a shame if he does not seek any knowledge on "what not to do".
Paul in PA
rfc, Seeking Enough Knowledge To Be Dangerous
> It is a shame if he does not seek any knowledge on "what not to do".
>
> Paul in PA
Actually, I meant the original question to be regarding an auto level, not a digital level, and probably did not make it clear that the question was in relationship to layout, not a running a level traverse.
If used from a single occupation, and observing a level rod at various locations within sight, I'm not sure why it wouldn't be a satisfactory way to quickly compare elevations in the field (compared to using a prism target).
But in any case, I'm not sure what you mean by "dangerous". I seek out (and have learned), what not to do all the time.
rfc, Seeking Enough Knowledge To Be Dangerous
Can't remember when I last used my Wild level.
Total Station is used in all setout and odd levelling jobs.
I haven't found any issues and often run closed loop level and horizontal traverses using forced centering and targets.
We adopted that as standard soon after Total Stations came into use.
The obvious advantages of a level are cheaper, quicker in some cases.
Overall I'd use total station in preference.
There's obvious caveats to all this. Accuracies required, type of survey.
I'm talking generally.
when used the right way, a total station could be used as a leveling instrument. look for prior posts by and about both charlie glover and jesse kozlowski. they have tested and made reports about the feasibility of this. fascinating possibility
> when used the right way, a total station could be used as a leveling instrument. look for prior posts by and about both charlie glover and jesse kozlowski. they have tested and made reports about the feasibility of this. fascinating possibility
Wow. Those guys are something else. Are they still around? Jim Frame mentioned a report written by Kozlowski in a 2010 post whose link was broken, but I did a google search and think I found it. Fascinating indeed.
When I asked the question, I was thinking very close work; construction layout (Not 70 km!) This is a whole other world.
Using a TS as leveling instrument
Well, since I started the thread, I feel privileged to hijack it somewhat...
In this thread:
https://surveyorconnect.com/index.php?mode=thread&id=202444
Kent said:
>That being the case, assuming that you have a total station that can measure zenith angles with a standard error of 3 seconds or better as the mean of both faces and can take care of the basics like determining the target heights, the critical part of the work will be the target and the quality of seeing along the line. Ideally, you'll want to use a target that you point the telescope at with much less uncertainty than the standard error of the zenith angle measurement. As for the seeing, that will vary by time of day and other factors such as cloud cover and the nature of the surface.
Is it reasonable to expect that whatever accuracy of a total station is determined in the horizontal circle, is likely applicable to the vertical glass as well?
Expect 50 % Vertical Versus Circular At Best
The farther one gets from the instrument, the greater the vertical information varies from a simplistic formula.
Refraction being one cause.
Curvature of the earth another.
More importantly, horizontal angles are determined based on a full circle of measured increments. Even if the full vertical circle has equal increments, the plumb azimuth is determined by a separate device with greater error.
"Dangerous" the most important part of education is knowing what you cannot do.
Asking questions can only get you so far, especially if you do not know all the questions that need to be asked.
Paul in PA
Using a TS as leveling instrument
rfc, the topic has been covered pretty well here over the years. The short answer is yes, as long as you follow good procedures - just like a normal level. Play around with your own equipment until you're satisfied.
Me, I've been running levels with my 3 second robot for years. I use it for virtually all my construction staking, and have had good results.
For a level run, balance your shots to under 600 ft or so, try and keep your zenith kinda close to as level as possible (that's just me), shoot them direct and reverse and split it. I never use the data collector, just old fashioned BS & FS. I don't carry an HI and always leave my rod height the same.
For on site staking, keep your perimeter control intact and check it as needed. Like normal, always re-stake a previously set stake (from a different setup) for another check.
It's slower to use and more awkward than a level.
rfc, Seeking Enough Knowledge To Be Dangerous
:good:
> You may want to brush up on Total Staion errors
Isn't it unfortunate to make a spelling mistake when we provide advice to our pears... 😉
> > You may want to brush up on Total Staion errors
>
> Isn't it unfortunate to make a spelling mistake when we provide advice to our pears... 😉
1. I clicked right through to the link and never gave the spelling a second thought.:-)
2. I've never been referred to as a "pear", but if you meant "peer", then I take it as a huge compliment!:-D
I really think he meant "pear"....... as your questions clearly show your true colors.
[sarcasm]Is their a keetle around hear?[/sarcasm];-)
A total station is being used as a level everytime I use it for topographic surveys.
A level is an instrument that gets elevation readings of survey points. This is what a total station is doing every time it takes a reading using a prism or in reflectorless mode.
It just depends on your needs. I get closures of 2-3 cm for <5 total station control points in a loop. For me that is more accuracy than what I need for making a toopographic map whose contour interval is 1 m.
I don't use a total station for construction grade layout because they usually want accuracies in the <1-2 cm level. For this type of work I use a digital level to transfer elevations across a construction site.
Results of a Two Peg Test
> A total station is being used as a level every time I use it for topographic surveys.
> A level is an instrument that gets elevation readings of survey points. This is what a total station is doing every time it takes a reading using a prism or in reflectorless mode.
> It just depends on your needs. I get closures of 2-3 cm for <5 total station control points in a loop. For me that is more accuracy than what I need for making a toopographic map whose contour interval is 1 m.
>
> I don't use a total station for construction grade layout because they usually want accuracies in the <1-2 cm level. For this type of work I use a digital level to transfer elevations across a construction site.
I just ran a Two Peg Test. With single faces only,(two sets), my delta is .014'. Meaning both faces, and doing two sets gets me .012', which seems in line, if not a bit better than your 2-3cm for 5 set-ups.
For construction though, on a small project, if there are only one or two setups, and one used the available horizontal control for each, wouldn't that come well within what "they" (the "construction folks"?), want?
