Loyal
wouldn't the picture you showed be an adjustable-height tripod?
The one above that is a tripod where you can't change the height.
Loyal
YES...
That particular SECO Model allows for 3 “fixed” height setups (1.5, 1.8, & 2.0 meters). My older (cheaper) SECO, is like Jim's photo above (2.0m only).
I REALLY like the “variable” HI models, and wish that I had bought another one when I had the chance a few years ago (Brand new in box w/ soft case for $350).
Loyal
gps measure up ''Every Time As Well As Always''
:good: :good: :good:
Pretty Amazing........
:good: :good: :good:
Baffling, isn't it?
Loyal
You got a great deal, I paid between $750 and $900 per for our adjustable fixed height tripods. The real problem with these is centering, the damn bubble seems to go out of adjustment if you look at it wrong. We spent more time adjusting them on every set up that seemed worth it so I went back to goo old tripods and the Leica tape hook. I only break them out when a contract requires them.
Loyal
I had one of those at my previous job. I don't remember the 1.8m stop; I think it only had 1.5 and 2.0 meter stops. It has a pin you put through the lower pole to prevent slipping.
My experience with that tripod was the same. I couldn't keep the bubble in adjustment and it was difficult to set up; a big gangly aluminum thing that likes to bind up. If the monument doesn't have a dimple then the point would slip off. I stopped using it and started using tripod/tribrach and measuring the antenna heights.
John
Yeah, they are pretty sensitive.
I arraigned for my main client (County Surveyor) to buy two of them (same price), and we/they now use them exclusively for the RTK Base Station setup. We average about 9 hours on each base, with 3+ occupations spread over a month or two (we have 14 spread over 9 months on one of them), all processed through OPUS and LSA'd together for a pretty tight Base position. I find the horizontal “repeats to be about 5mm or LESS between setups, and that ain't too bad all things considered.
Loyal
Pretty Amazing........
I dunno guys...
SOP for me has been to measure the HI on EVERY setup (Total Station or GPS) since I stopped “chaining.” It was never [so much] about “elevations” in the “control” sense, it was about getting GOOD horizontal measurements.
I routinely run into Survey Crews traversing around the Mountains that not only DON'T measure HIs, they don't record vertical angles (unless the data collector does it for them), DON'T have a barometer or thermometer, and appear to still believe that the Earth is a flat plane with bumps (hills/mountains) on it. In most cases, even the guys that have ALL of the actual field data (HIs, verticals, etc.) often IGNORE all of that when they solve/adjust their traverses.
Most surveyors that I run into using GPS are the in the Calibration/Localization Society, and I guess that works “okay” for their purposes (or at least they THINK it does).
The more things change, the more they stay the same...
Loyal
Pretty Amazing........
The original Post was with regard to what effect not recording the HT would have on the measurements. Not whether it should be SOP or Not.
Somehow it got totally hijacked into using proper field procedures when that wasn't the question.
It seems that reading comprehension should be offered as PDHs:-)
Loyal
They are sure easier to set up than those huge fix-height things. We messed with those for a big height-mod. survey and, while being nice and tall, they weren't very versitile.
The one you show can adjust and you can set the height at a stop. Much nicer.
Pretty Amazing........
Most of the time I don't need elevations; I just never differentiated between horizontal-only "boundary" projects and other projects which required elevations such as topography and staking.
I adjust all projects in 3D partly because most involve at least some static observations. I do know my elevations aren't necessarily highly accurate unless I take steps to make them highly accurate.
I have heard in person several times from other Surveyors that this is a "Boundary-only" project therefore we don't need good heights. I disagree, the mountainous nature of our work suggests that we should be concerned about heights. If we are doing a Lot survey down in the valley then it doesn't make much difference but I measure heights anyway.
Pretty Amazing........
It's a discussion forum. The discussion will go where it leads.
It doesn't have to do with reading comprehension or hijacking. If you throw something out, expect it to get discussed.
I've had this discussion in person too. I just don't get it, what is so hard about measuring a height? You brought it up which brings the obvious question, "why do you feel it is such a burden to take 5 seconds and measure a height." I mean why bother to center the instrument over the point, that takes a lot longer?
Pretty Amazing........
> Most of the time I don't need elevations; I just never differentiated between horizontal-only "boundary" projects and other projects which required elevations such as topography and staking.
>
> I adjust all projects in 3D partly because most involve at least some static observations. I do know my elevations aren't necessarily highly accurate unless I take steps to make them highly accurate.
>
> I have heard in person several times from other Surveyors that this is a "Boundary-only" project therefore we don't need good heights. I disagree, the mountainous nature of our work suggests that we should be concerned about heights. If we are doing a Lot survey down in the valley then it doesn't make much difference but I measure heights anyway.
In this day and age a 3D survey whether it be with a total station or GPS is a no brainer.
Unless you're using a transit with stadia or some other primitive technique it shouldn't take that much longer (the occasional 15-20 secs. to change rod heights etc.), so it would make sense to do it whether you need it or not.
But I'm not sure that was the original intention of this thread.
Ralph
Pretty Amazing........
Surprising how often you (or the client) later wishes you had some good elevations. How much longer does it really take to carry elevations. As I said before, if you sometimes do need elevations it is so much safer to get into the habit of always carrying them.
Pretty Amazing........
> I just don't get it, what is so hard about measuring a height? You brought it up which brings the obvious question, "why do you feel it is such a burden to take 5 seconds and measure a height." I mean why bother to center the instrument over the point, that takes a lot longer?
It looks to me like you do get it. There are some people who are all about cutting costs and time is money. If they can save 5 seconds a set up, 20 set ups a day, 5 days a week, 52 weeks a year......If you do the math, you've saved a lot of money over the years.
To me, compromise has never saved me money. In fact I've seen it cost money.
Dugger
Pretty Amazing........
I just don't get it, what is so hard about measuring a height? You brought it up which brings the obvious question, "why do you feel it is such a burden to take 5 seconds and measure a height." I mean why bother to center the instrument over the point, that takes a lot longer?
I bought it up???
This was obviously posted by someone using a pseudo name, I wouldn't be surprised if that same person came back under his real name to flame himself.
Ralph
Loyal
> The original Post was with regard to what effect not recording the HT would have on the measurements. Not whether it should be SOP or Not.
>
> Somehow it got totally hijacked into using proper field procedures when that wasn't the question.
>
> It seems that reading comprehension should be offered as PDHs:-)
I didn't mean anything by the above post, it was intended as a joke. I have a great deal of respect for you and all you've contributed to these forums. I've learned a lot from you.
Thanks for being you:-)
Ralph
Loyal
> They are sure easier to set up than those huge fix-height things. We messed with those for a big height-mod. survey and, while being nice and tall, they weren't very versitile.
I find the "huge fix-height things" very easy to set up, and have taught dozens of newbies -- mostly public agency staff pressed into service for height mod projects -- to do so in just a few minutes. They require a lot of lay-down space for transport, but I designed the box in my truck to accommodate the 4 that I own.
Ralph
No problem-o buddy, and thanks for the kind words.
Like Dave indicated, these types of threads DO tend to evolve somewhat, and sometimes that when the really good stuff happens...
Loyal
Loyal
> adjustable fixed height tripods.
You have to love the way we talk.
What was it Yogi said? No one goes there anymore because its too crowded.