The Pole Height is limited to 6,4 m in Emlid Flow. I have customers that want to measure down in deep man holes, and sometimes up to 25 meters. Why do we have the limitaions at 6,4M? Can EMLID change this?
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I would like to input negative heights as well
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@rolf Interesting question, I will await the answer
thanks
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This doesn’t solve your exact problem, (and Emlid probably will not entertain that very long pole height request for good reason) but seems Emlid Flow needs an Invert measurement mode?
I.e. like Microsurvey Fieldgenius has:
I guess a work around is duplicate the reference point that was normally measured with the receiver, manually measure down into the hole (invert) and subtract that from the manually created point’s elevation for your manual Invert Point.
I am sure Emlid will add to their very long and exausting road map : / “Are we there yet? Are we there yet?”
It would REALLY REALLY be ideal if Emlid would just hit this hard in WARP SPEED and just implement as many as all the features Fieldgenius has had for MANY years now. I mean these are standard features all survey software have. Emlid has that ecosystem and needs to solidify that.
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Hi Tim,
Can you explain why a longer pole wouldn’t solve my problem? It’s not me requesting this, it’s a customer, a contractor. They want simple solutions. How would you measure the depth of a 14 meter manhole? With EMLID Flow in the field? And we have several customers maskin the same question.
Chers Rolf
Measuring deep manholes is easy. I measure from the rim with a Leica Disto D8. I think the deepest I’ve measured is about 12’. Measure then subtract from the rim elevation and you have an invert.
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I’ll let Emlid explain that to ya 
Good 
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Its easy yes if you have a Disto. But this is a contractor who would have less gear to carry, sure they can afford a Disto.
Why complicate things?
Hmmmm? Carry a 25m pole everywhere or a handheld EDM (some are dirt cheap if funds are insufficient) or better yet, because who doesn’t own a tape measure???
As suggested in the thread, this is standard procedure for inverts and a STANDARD feature in professional survey software.
True, it’s not what they do often. And normally they just need a bit longer than the current limitation.
They have telescopic poles already. Those holes are often filled with water. This is a contractor who do horizontal and vertical drilling among other work tasks. I have explained all alternatives that pops up here and have access to Disto, can sell it. I am just explaining what the customer asks for. Why can’t EMLID extend the pole height limitation a bit?
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Having surveyed manholes for decades, I agree with the above posters here that said
"Get the elevation of the rim/cover and then measure down to the inverts in and out with whatever method is easiest [Disto, tape, etc].
[@EBE111057 , @timd1971 , ]
I learned early on not to stick the rod into a flowing sewer manhole invert 
Typically, it is easier to measure with a tape than with a rod/pole due to the fact that inverts are not always accessible on the full inside of the manhole structure.
Just my humble opinion.
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We understand the OP’s frustration… but ultimately, besides the practicality of a 25m rod with a receiver dangling at the top of it (or even not so long), that the reasoning for the limit is something Emlid can only provide.
Personally, gonna stick with a tape (if filled with water, debris etc) or a handheld EDM. If need be, can drop a long pole down, mark it, pull it out and measure along the pole manually horizontally on the ground.
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Regardless of bubble the vertical angle uncertainty over 25m is going to play havoc with any horizontal position accuracy, let alone potential vertical height blunders resulting from where extensions may or may not be locked.
Assuming in this case they are primarily interested in depth, are they intending to try and pull out all 25m as locked to validate the length measurement? If it doesn’t bend in half while doing so, then it’s probably to heavy and bulky to use in the first place.
The idea seems to defeat the original positioning purpose. Otherwise as Bryan said, they should use the right tool for the job.
For what it’s worth Trimble limit the configurable antenna height in my NetR9 from 0 to a max of +4m.
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Ah screw it… it’s OVERKILL…
this is what you need and call it a day… 
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Hi @rolf
The pole height is fixed at 6.4m to ensure the best possible accuracy for our devices. However, I can see how this can be a helpful feature, so I’ve passed it to our development team.
As @timd1971 mentions, as an alternative solution, you can measure a point on the surface and then use a tool to calculate the exact z level. You can do this in Emlid Flow with the Traverse tool. You need to select the measured point, give 0 for Direction and 2D Distance, and set the Height Difference. After that, you can save it as a new point with the correct height.
@gredwards, can you please elaborate on why you would need negative heights?
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i would like negative target heights to enable direct measurement of LAT vs AHD heights when dealing with the sea level datum is below MSL datum
@csaba.galli , this works well