I got confused on a survey question

You really have to read that question carefully to get what they are asking. It reminds me of many questions on the FS and PS tests in that sense. Perhaps it could be asked better, but maybe a test of reading comprehension was intended.

I tried and carefully re-read the question before i made the comment, and here's where i'm getting confused. The way I read this question is this is a standard level setup where the level is placed equidistant between points and a backsight and foresight is taken.
If the backsight reading were 3.90' and the foresight reading were 4.25', does that change the answer ?

Thanks though. I understand what you're getting at.

Think of it this way: You've set up the level in a standard setup as you described above. You take a reading on the benchmark and get 3.90'. The new point you need to set is supposed to be 2.00' lower but instead of moving the target up the rod to 5.90' you catch a brain cramp and only move it to 5.70'. This leaves the target 0.20' low, but what does it do to the height of the point you just set?

Edit: The key is to realize that you are "staking" a target elevation not determining the difference between two existing points.

Sounds like they are referring to a rotary level where you would clamp the receiver to the rod. Clamping the receiver 0.2' too low would produce an error of 0.2' too high. But if I were using an autolevel or digital level and clamped the rod 0.2' lower than the crows foot I put on the wall, it would produce an error of 0.2' too low. I am a surveyor and don't use rotary levels so I got this question wrong...

I go with .2 too high.

.2 too high

I think they are referring to a Lenker rod but how would you know?

I can't read their mind.

Dave Karoly, post: 420367, member: 94 wrote: I think they are referring to a Lenker rod but how would you know?

I can't read their mind.

That was a thought I had until Mark mentioned reading the question carefully (which I thought I did). And it mentions 'if the rod was clamped 0.2' too low from the correct setting for the point reading only' which doesn't occur since you set the Lenker rod at the benchmark.

The rest of the question asks 'by how much would the point's elevation be in error'. The point's elevation wouldn't be in error, what elevation you think it is could be in error, but that depends on if you were using a Philly or Frisco rod, and further depend on what part of the rod you read. You could make a case there was no error depending on your backsight and foresight readings.

That's a pretty poorly written question...... The way I read it is it's a standard philly rod that's not fully extended when the clamp is tightened.....it doesn't mention rod face, target, laser indicator, or anything... it says the rod is clamped 0.2 lower for just this single shot. that eliminates 1. no error.
The shot is taken 0.2' too high on the rod giving a LOWER elevation (HI-FS= elevation) that the true elevation of the point; therefore the you nmust try and deduce the final portion of the question.... do they mean is the erroneously determined elevation higher or lower that the points true elevation? Or do they mean is the true elevation higher or lower than the elevation as erroneously determined? I'd go with 4. 0.2 lower ...... just because I get the sense that's what they're failing at attempting to ask.... not GET OFF MY LAWN!

The fair part of the CST test comes at the end of the day. The examinee has to submit the answers on time, but the proctor has to wait for examinees to write 'challenges' to questions after the submission time. A panel meets later to review these challenges to decide: 1 to give credit for a badly written question and a best response to it, and 2 to eliminate or re-write the question for the future.