Magnet Tools (again)

I've never been a fan of their software. I do still like their total stations but not as much as I used to. Can you make the switch to a different software?

I honestly think that's our only option. We are considering a return to Carlson for data collection and StarNet for processing and adjustment.
It is my understanding Carlson has made a few changes that make it friendly for the GPS / Least Squares crowd. I've always loved StarNet but we need a newer version. 5.0 doesn't play well in Win7 64 bit...

Magnet projections with grid to ground scale factors work for well for me. I've only used the original state plane projections installed in software. From reading your other threads, I believe you are using a custom projection, and there may lie the problem. Also I work on grid, and have the software reduce my ground distances to grid coordinates. That appears to be another difference in how we work.

If you want to work on ground, then I think there is no need for a scale factor.

What software and procedures are your peers using, to accomplish your needs?

Lee Green

I'm like Leegreen, I also almost always work on grid. If I'm adding shots with a total station, I just let the data collector convert the distances to grid distances. If I'm doing a boundary survey and need ground distances I just do that work in Cad. If I'm in the field and need a ground distance, which isn't very often, I usually just do the math in my head but I also work in an area where the scale factor is pretty close to 1.

The actual problem you are having with Magnet I can't help you with since I'm still using TDS.

In Magnet no need to calc grid to ground distances in your head.

When scale factor is toggled on, and proper scale is set. You will see both grid and ground distances in the Inverse report.

Example from Magnet Field 2.7.1
From Point 20
To Point 550
Ground Results:
Bearing N56°08'05"E
HDist 3761.064 USft
dNorth 2095.825 USft
dEast 3122.999 USft
dHeight -2258.515 USft
Grade(Slope) -60.050 %
Slope distance 4387.082 USft
Grid Results:
Bearing N56°08'05"E
HDist 3760.438 USft
dNorth 2095.476 USft
dEast 3122.479 USft
dHeight -2258.515 USft
Grade(Slope) -60.060 %
Slope distance 4386.546 USft
Geodetic Bearing N55°47'59"E
Geodetic Dist 3760.745 USft

Also when you manually enter distances in cogo on Magnet. You can click on the distance type to select whether you wish to enter a GRID distance or a GROUND distance.

Here is GRID distance, see yellow highlighted button.

Here is GROUND distance, after click on the yellow highlighted button.

When working in State Plane we enter 1/CAF to generate nominal ground coordinates. These are needed by the crew to determine which positions need more data or QC. This has been part of my work flow for decades and Topcon claims it works. When working in my custom projections we cannot get the software to generate coordinates from total station data without checking the box and setting scale to 1.
The issue we have is that Magnet Field and Tools randomly change the hand entered parameters and scale from a point in the job. It also assigns coordinates of 0,0 to the point, effectively translating the job to another continent.

Sounds like you are using scale factor as not intended for design in Magnet. Your process is backwards.

You can NOT work from ground to grid that way. Not sure how you've done it for all this time.

I don't know anyone working like that. Are you sure others in your area use this method?

EDM use ground distances, all coordinates are grid. GNSS are reduced to grid coordinates also.

There is NOT ground coordinate system. It would be an assumed coordinate.

You are certainly outside the box.

Maybe Kent can help you......

Lee,
Precomputing parameters for grid to ground has several advantages. I can check distortions over my project area, maintain simple parameters for computing ground values and have legacy data or precalcs on datum before leaving the office. The option to enter the inverse of the CAF ( incorrectly called scale factor) is there to accommodate hand entry of a precomputed value.
While my way certainly isn't the only one, it is efficient and produces excellent results. It is repeatable and more than sufficient for the task at hand. I prefer not to allow Magnet to handle computing the parameters as it is often grossly incorrect.
As for 'how I've gotten by with it', that's simple. I do good work and make money. This method isn't my only bag of tricks. Some projects require technically correct reduction of the total station data, including application of the minor corrections we generally ignore. The difference is too small to be concerned with on a 2 acre parcel.
The measuremnent part of Surveying is about choosing the right tool and using it the right way for the job. I have learned and developed a wide variety of combinations over the years. I can compute and express what I've done and how well I've done it. Tell me how that is wrong...

Sounds like you have good reason, this is not something I'm familiar with. You must be working in area with large scale factors and much elevation change.

Have you tried logging a support ticket with TopconTotalCare.com?

Topcon support is difficult to get to. Have to go through your dealer, let them exhaust their efforts. Then be persistent that the dealer logs a ticket with Topcon and get proper support.

It's a PITA, but does get things done. TopconTotalCare.com get's your questions to Topcon directly.

Lee Green

The CAF where we work runs between .1 and .3 feet in 1000. Using the 1/CSF in the scale factor setting can bring that distortion down to less than 0.01 per 1000' over an area 1 township in size. My custom LDPs are about the same.
I have started several tickets, all leading to the same end. If there is any communication at all it's a message stating they consider it resolved. I finally requested an appointment with my vendor to review other software options. Suddenly they are all ears.
If I don't see progress this week I'll be posting a review of the newest StarNet soon.

Have you tried creating a custom projection with the same parameters as the state plane zone you are working in and using 1/CAF there? Also my guess is that your software does not allow you to apply the 1/CAF to total station data in a custom projection because total station data is already at ground. Can you apply the CAF in a SP zone to get grid? I dont use magnet so not sure how helpful this is.

Most of our custom projections use the same central meridian and latitude of origin as the zone they are in. The scale factor is based on the horizontal center and mean elevation factor of the township. The formula is 1/CSF * scale reduction = projection scale factor. Even these will not process total station data in Tools without setting a scale factor of 1.
When we are in State Plane the field software usually uses the CAF properly until it decides to change it. That is one feature i can do without...