TOPOGRAPHIC SURVEYS

Have a review question that states that when performing a topographic survey on a 1/2 acre rectangular piece of land that a radial-total station survey would be more appropriate than a Grid survey or photogrammetry. Does anyone know why? And also, any reference that indicates under which circumstance a grid would be appropriate? Which circumstances a radial would be appropriate? Photogrammetry would be appropriate?

Thanks

Off the top of my head, I can answer regarding the photogrammetry......this one would be used for lage areas of land (probably in the range of several hundred acres if not more), which would make it cost-efficient to be taking photographs from an airplane. A half acre piece of land is around 22,000 square feet.---wouldn't be worthwhile to rent a plane and pilot to take a picture of this....would be much more economical to measure from the ground.

Sometimes with these types of problems, it helps simplify the problem if you can immediately determine what kind of scale of land you are dealing with-->this will usually rule out an option right from the beginning.

Bigwolf said:

Off the top of my head, I can answer regarding the photogrammetry......this one would be used for lage areas of land (probably in the range of several hundred acres if not more), which would make it cost-efficient to be taking photographs from an airplane. A half acre piece of land is around 22,000 square feet.---wouldn't be worthwhile to rent a plane and pilot to take a picture of this....would be much more economical to measure from the ground.Sometimes with these types of problems, it helps simplify the problem if you can immediately determine what kind of scale of land you are dealing with-->this will usually rule out an option right from the beginning.

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Thanks Bigwolf. I agree with you. I was able to rule out Photogrammetry. I was stumped between the grid and radial. I guessed grid and the answer was radial. I'm not sure why though.

ARJ said:

Have a review question that states that when performing a topographic survey on a 1/2 acre rectangular piece of land that a radial-total station survey would be more appropriate than a Grid survey or photogrammetry. Does anyone know why? And also, any reference that indicates under which circumstance a grid would be appropriate? Which circumstances a radial would be appropriate? Photogrammetry would be appropriate?
Thanks

Click to expand...

With a total station, radial survey clearly is more efficient that grid. This is because you can set up the total station at one known corner and walk around with the prism to collect data of any point/object within the total station range. You don't have to lay out grids when using a total station.

Thanks again relieved. I really appreciate your help.