Does hot weather affect the precision of digital leveling? Recently a crew ran a peg test on a digital level in the afternoon. The level exceeded maximum tolerance. The next morning it was within tolerance.
Were they shooting through heat waves?
Does hot weather affect the precision of digital leveling?
Somewhat. But not dramatically in my experience. Heat shimmer affects range more than accuracy.
The thing with digital levels is that the reading error is so small that the stability of the turning point becomes the critical source of error. Also, if you took the instrument from the air conditioned office out to the hot afternoon sun, and didn't allow time for the instrument to acclimatize, the readings may be in error.
The Leica manuals say to shade for peg and maybe for precise work, an addition with the new LS models; shading was not mentioned in the old DNA manuals.
*From offhand memory only.*
Field Dog the answer to your question is YES.
Look at chapter 3 of Electronic Surveying Instruments, A Review of Principles,
problems and Procedures by J.M. Rueger