topic LIDAR Scaleing in Civil 3D Forum

LIDAR Scaleing

Anonymous — Sat, 25 Jun 2016 17:17:32 GMT

Two Questions:

1. How do I go about converting LIDAR files from metric to English.

2. If I create a new surface and the bring in the LIDAR info I need into the surface can the LIDAR Files then be deleted?

Both questions are for Vrs 2015

Dave Z.

Re: LIDAR Scaleing

Pointdump — Sat, 25 Jun 2016 18:21:09 GMT

Dave Z,

Depends. In what format are they? LAS, LAZ, zLAS, ASCII? Best to post 'em. If the Forum won't accept that format, zip them up.

Dave

Re: LIDAR Scaleing

Anonymous — Sat, 25 Jun 2016 18:38:41 GMT

LAS Zone 14-15 NAD 83

I can't get the zip file to attach

Re: LIDAR Scaleing

Pointdump — Sat, 25 Jun 2016 18:54:47 GMT

Dave Z,

What size is your LAS file? The Forum will accept up to 75 MB. Zipping should work. How is it hanging up?

"Zone 14-15 NAD 83"

Is that UTM83-14 or UTM83-15?

Dave S

Re: LIDAR Scaleing

Anonymous — Sat, 25 Jun 2016 19:25:01 GMT

I have no clue. I will get on the kansas usgs site and see what I can find

Re: LIDAR Scaleing

Pointdump — Sat, 25 Jun 2016 19:46:17 GMT

Dave Z,

When you create your point cloud database (bringing in your LAS file), you specify the drawing's Coordinate System and the Point Cloud's Coordinate System. It should transform automatically. With data we can test.

Dave S

Re: LIDAR Scaleing

Anonymous — Sat, 25 Jun 2016 19:59:32 GMT

Ok the site has
Projection data: UTM zones 14-15/Nad 83
I have created the point cloud. Can the Coord system be changed. Or do I need to start over?

Re: LIDAR Scaleing

Anonymous — Sat, 25 Jun 2016 20:02:24 GMT

What is going on with this site. I didn't mark it as excepted

Re: LIDAR Scaleing

Anonymous — Sat, 25 Jun 2016 22:39:59 GMT

Ok no mater what coordinate zone I use my lidar point elevations are still showing in Meters and not in feet. They need to be in Feet.......ggrrrrrr.

AutoCAD needs to add a conversion process in the program.

PS The US switch back to Imperial several years back. Why is metric still being used.

dave z.

Re: LIDAR Scaleing

Pointdump — Sat, 25 Jun 2016 22:59:18 GMT

Dave Z,

"Why is metric still being used."

Dunno. But even if the US went metric tomorrow, there would still be a LOT of drawings and data out there using different units and Coordinate Systems.

I still think C3D will transform that data automatically. Please post your data.

Dave S

Re: LIDAR Scaleing

Anonymous — Sat, 25 Jun 2016 23:11:43 GMT

The las file is over 600mb. Will try and zip the file or see if i can do just a small part in the morning

Re: LIDAR Scaleing

Pointdump — Sat, 25 Jun 2016 23:35:23 GMT

Dave Z,

600MB? That's a serious LiDAR point cloud! Is it the ENTIRE state of Kansas? Are the points classified? Link please.

You'll need some tools to chop that up, something like LAStools:

https://rapidlasso.com/lastools/

Dave S

Re: LIDAR Scaleing

Anonymous — Sun, 26 Jun 2016 00:37:24 GMT

It's what they call a panel. Which their site says is 5000m sq.
I will try and post link to their site

Re: LIDAR Scaleing

Pointdump — Sun, 26 Jun 2016 08:53:01 GMT

Dave Z,

I played with some Minnesota Data in UTM83-15 Meters this morning(LAS file attached) and Civil 3D does indeed handle the elevation conversion from Metric to Feet. I assigned one drawing UTM83-15 Meters and one UTM83-15 Survey Feet. Here's the results:

Dave S

Re: LIDAR Scaleing

Anonymous — Sun, 26 Jun 2016 13:29:48 GMT

Ok Got it to Work this time. It is now readying the elevations in feet as shown on your images above. Not sure what was going on I didn't do anything different. Unless something cleared its self when I shut down the system for the night and restarted this morning.

Ok so now to get the elevations to read correctly. (Say 1500) I Take 427.277x3.2808=1500.00. Then 1500.00-472.277=1,027.723

Then adjusting the surface up 1,027.723 to get correct datum elevations.

Re: LIDAR Scaleing

Pointdump — Sun, 26 Jun 2016 15:11:11 GMT

Dave Z,

"Take 427.277x3.2808=1500.00. Then 1500.00-472.277=1,027.723
Then adjusting the surface up 1,027.723 to get correct datum elevations."

What happened? Wrong vertical Datum? Why do you have to adjust them?

Dave S

Re: LIDAR Scaleing

Anonymous — Sun, 26 Jun 2016 16:21:48 GMT

Dave

Take a look at your last image above and note the min. & Max elevations.

When I adjust the surface base on your last post the datum elevations read as normal.

Also when I hover over the surface the datums read correctly.

Thanks for all the help. Really appreciate it. Watch for my new post...coming soon.

Dave Z.