Remember that with this level of accuracy cleanliness is absolutely vital. You certainly won't be running km. length lines across muddy fields. More l...
@jim-frame Only too true. You need a small bit on the iron AND a steady hand. Don't try it unless yuo are confident. I shan't ask how you managed to ...
@bill93 Don't mix up precision and accuracy. Even on a 30m. sight you can get quite large variations in refraction. Just with the ray passing very cl...
Whoops - meant 0.4KM!
@mightymoe All depends on the site and if you can drive it. Some of the quarries it used to take me all day to walk can be done in less than an hours...
@andrewm Yes,for that type of work we expect 1-2cm. accuracy in height - plan accuracy for that type of work isn't so iimportant. Of course, since yo...
@mightymoe Guess that drone figure is a "mathematical" achievement, rather than a practical one. To check it on the ground every reading taken would ...
@stlsurveyor if the boards need to stay down for a while, rather than just for the day, then the 18 inch boards stand up better to wind, etc. than 2 ...
@stlsurveyor In the early days when we tested various options we tried 8 inch targets: they did work but not as well as the larger ones. With the Son...
40 acres is a small experiment. The difficulty with a much smaller site is that there wouldn't be much room for the software to make errors, so you wo...
@bill93 Visually I find it better to "see" the chequer board, but using both Pix4D and Photoscan results seem to favour the cross. I guess it is beca...
A few general points to bear in mind. GSD is not the same as accuracy. I'm assuming that you are using the boards to check the "accuracy", so you ar...
@paul-in-pa Agreed. The first thing we do when returning to the office is to download the instrument data and PRINT IT OUT. Paper is much more durabl...
It might be a case (pardon the pun!) of damp instruments not being taken out to dry. If they are damp then any dirt on the packing gets transferred to...
Welcome, Newcastle Northern Ireland from Newcastle England. You'll find it interesting seeing the perspectives from all around the world
I dril a 3mm. hole in the concrete and then hammer in a 4mm. stailnless steel machine bolt, with countersunk crosshead. The threads cut into the concr...
When this section of road was built back in the 80's the contract was in two sections - north and south of the junction. The designs for each were bas...
From your description of the mud it sounds as though "load spreading" would do the trick.?ÿ I've made up a triangular frame of 4"x2" with triangular p...
Looks very good. I've used a cheaper method for years. I had a series of "probes made up - flat bars of length 0.5, 1, 1.5 metres with a standard 5/8...
@bill93 I think he did - I've re-celled those with replacement SLA's. My own version with Li-On is much, much lighter but the SLA are much, much chea...