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Might have to take the plunge and get into GPS Station Surveys  

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squowse
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You might find that you can do what you need with a manual total station. Can get a good one for £2000 secondhand.

Reflectorless shots for the buildings, walls etc; and get a bipod or similar for spot levels. Bit of walking back and forth but might not be too bad for small surveys. Can be used for setting-out as well. On a clear site it's easy to use reflectors etc; for one man non-robotic operation.

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chris mills
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I'd partly agree with Squowse -but working by yourself with a manual total station isn't easy of you want to get topo over the whole site. For each shot where a ground level is needed you would have to move the target, go back to the instrument and observe.  If you can afford it you are much better off with a robotic unit.

Remember that with a total station you can run the control into the building and fix a number of points to help tie up your internal taped measurements - saving a huge amount of time in old buildings where nothing is quite straight. A traverse down each corridor and a couple of shots into some rooms make everything a lot easier (assuming you aren't going to splash out on a scanner!)

The only benefit you might get from GPS for your sort of work is that you could establish the site reference point onto OS datum easily, without running to the nearest benchmark, but I suspect most of yours are to a local datum anyway.

Without any survey experience don't buy off the internet - you need a dealer support for the gear and if you buy through a dealer you can be assured that spares and service will be available for some years. (Christ Lambrecht is probably getting rid of his R6s for the same reason that ours will be replaced - Trimble have stopped providing spares for the early ones).

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Norman Oklahoma
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GPS doesn't work under trees or near buildings. And be very sceptical if you are in these conditions and the controller assures you that everything is fine and accurate.

I'd like to temper that remark somewhat. GNSS will work, more or less, under some tree cover and near buildings - to a degree, at least. But the coordinate quality will be degraded and it will quit returning positions altogether when the obstructions are enough. Which doesn't have to be all that much.

A common misconception is that the base collects satellite data and transmits it to the rover. Not so. Both base and rover need to be collecting data from common satellites to get positions. When the data at either becomes to noisy, or the number of common satellites drops below the minimum, fix is lost.      

Without any survey experience don't buy off the internet - you need a dealer support for the gear and if you buy through a dealer you can be assured that spares and service will be available for some years. 

I think that is very good advise.

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ChrisA
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Sorry for the delay all, it's Friday night and I finally got round to responding, it's been a long week, though I actually managed almost a whole day off today, that was nice!

Sireath - Thank you for that, really kind. I think it will be frustrating at first and there's no doubt a lot of time will be used up getting things set up. I've probably said in a previous post, but I'm only doing this because the local surveyors don't really like small jobs and understandably have to price them similar to a medium/large sized job. It's often an issue that I want the information for greater accuracy and more useful drawings, but the client isn't prepared to pay for it. It'll no doubt take some time, but hopefully time I can gradually recover over...ummm, time.

Squowse - Funnily enough the unit I saw, that I thought would get me under trees (using a GPS system) has been confirmed as not working as expected - and by all people, the seller! Quite honest of them and glad I've got your comments to confirm this.

Thank you very much for clarifying my confusion, I'm so sorry to you and everyone for writing these seemingly silly questions, but over on this side of the pond there's very little information. Understandable of course, as I have knowledge about how I perform my work, and I'm unlikely to give that up for free, for fear of creating more competition!

About the idea of a £2k manual total station, I'll a little restricted on have a second pair of hands at conveniently short notice, so for times sake, a Robotic Total Station would be best...just not the best for my wallet. On the bright side, at least any borrowing interest will be tax deductible...but it's still my actual money that's being spent! Thanks again for your comments, it truly is invaluable.

Chris Mills - I think you're right re the Robotic unit, despite the cost increase. That also sounds superb that I can connect it with internal measures. You're right again re local datum sufficing, I'm not carrying out any large scale builds, normally just a house, or two at most, and mainly extensions to existing buildings.

Quite right about buying off the internet, I'm looking for local outlets first, but nationwide for general cost research. Oddly one has admitted that they can supply me with a Robotic Total station, however it's very old and parts would be difficult to attain if there were problems...quite honest for a body that wishes to sell something. That's a really useful headsup about Trimble, I'm sure that's a real disappointment for many. Thank you again!

Norman Oklahoma - Really appreciate you weighing in, I was under the (wrong) impression that the base need only to be in clear line of sight to sats, and then knows the position of the rover. From the outset I've respected and appreciated that this isn't an area you can casually drop by, and everyone here has indirectly conveyed that, quite rightly.

Thank you Norman, really invaluable info.

True Corner - Quite right, it is a much smaller area, however we have Ordnance Survey to thank for preliminary plans of every corner of the UK (as it's quite small, it was relatively easy). These are generally used to illustrate the extents of the ownership boundary, I would happily upload one as a sample if anyone is curious.

Chris Mills - Following on from your later comments, I've been involved in land purchases and despite the accuracy available to us, we still refer to the old Land Registry plans as 'gospel'. Clients assume that precise drawings are required, but often the revision of an old 1:1250 scale plan is sufficient and actually the only acceptable format. It's a funny country isn't it.

You're also right about the UK having a greater quantity of property owners, I think Germany is the highest in Europe, that's partly due to property not being used so much as an income source. That does need to be confirmed though, as I'm only going on memory.

Chris Mills - Sorry, just noticed you're in this country, hello! Couldn't agree with you more, I've dealt with party issues and it's just a specialist area. In principle, say in a terrace, you own half of the wall. That's simple enough isn't it, but like you say, in situations where the boundary is more vague, clients and owners will only end up lining the pockets of the legal beagles to fight out disputes. It's a strange world...or rather country.

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Dave Karoly
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The base should be as open as possible. Base and rover need common satellites so if the rover is marginal it may work if the base has a lot more satellites available.

U.S. boundary law is like U.K. boundary law with an inadequate scientific element thrown in to make it interesting. Much of the U.S. is arid and larger tracts so it doesn't lend itself as well to walls and hedges.

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True Corner
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Posted by: Dave Karoly

The base should be as open as possible. Base and rover need common satellites so if the rover is marginal it may work if the base has a lot more satellites available.

U.S. boundary law is like U.K. boundary law with an inadequate scientific element thrown in to make it interesting. Much of the U.S. is arid and larger tracts so it doesn't lend itself as well to walls and hedges.

Prescriptive rights don't exist in the UK.  Buying land in the UK is totally different than the US.

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