Output Scale Factor

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Larry H

Output Scale Factor

Post by Larry H » Wed Jul 02, 2003 10:48 am

I am working in UTM co-ordinates and want to publish ground distances. When I toggle on the Output scale factor I can view the ground distance but MSCAD labels the line with the grid distance. Is there a way around this?

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Location: Peterborough, Ontario, Canada

Post by rwhatman » Wed Jul 02, 2003 2:35 pm

The only way I know is that you have to change your UTM grid
co-ordinates to ground co-ordinates. MSCad just gives you the distances
as they are are and not what you want to change it to.

You can edit every distance, but that would be a pain.

You make a copy of the plan and change it to ground and copy the distances back the Grid plan.

Both sound painful.

Or you can do what I do and keep it simple.

I take my ground plan and move and rotate it into UTM.

All my distances are ground and yet have UTM co-ordintes.

Yes they are NOT Grid co-ordintes. You can't have it both ways.
The scale factor is so little that it make not much difference over
short distance.

I would set up two Control points that are on the plan that are grid.

I move the plan to one co-ordinte and rotate to the other point.

Now my plan is in UTM and all the distances will be ground and my bearings grid.

That how I do it.

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Darcy Detlor
Site Admin
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Location: West Kelowna, BC

Use the Distance Labeling Scale Factor

Post by Darcy Detlor » Wed Jul 02, 2003 6:35 pm

Hi there,

We built in a special scale factor option that can be used for exactly this problem. The scale factor is under the MicroSurvey -> MicroSurvey Defaults -> Distances menu item. On the right side there is a edit field labeled "Scale Factor:". The default is 1, but if you put in a value it will be multiplied by the distance before the label is applied.
Darcy Detlor,
MicroSurvey Software Inc.

Posts: 299
Joined: Sun Nov 10, 2002 6:41 am
Location: Peterborough, Ontario, Canada

Post by rwhatman » Wed Jul 02, 2003 7:13 pm

Hi Darcy

Yea I knew about that one. Its OK if your wanting to say
put feet distances on a metric plan.

I may be wrong, but in UTM co-ordintes, the x and the y have two different
scales and every point also has a different scale. You have to apply each
scale fator to each points x, y then if you subtract you get Ground Distance between them.

Now maybe the distance scale factor might be close enough.

As you know I have been wrong a lot.

Just another thought.

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Joined: Sun Nov 10, 2002 6:41 am
Location: Peterborough, Ontario, Canada

Post by rwhatman » Thu Jul 03, 2003 3:04 am

OK, I was not quite right. Example:
Here is a small sample of UTM83-17 points
Each point has its own scale factor.
I have not been able to view Grid Distance because of this.
I have had to convert each point thats on the grid to get the distance.
Or would I use the Scale Factor at the Centre Meridian. I my case, scale 0.9996 would be right.

Site Scale Elevation
ID Site Descriptor Convergence Factor Factor

1 0034 099940034 - 0 00.000 1.00015337 0.99997211

2 0507 - 0 00.000 1.00014992 0.99996796

3 0033 099940033 - 0 00.000 1.00014782 0.99996456

4 0201 001963021 - 0 00.000 1.00016909 0.99996587

5 0508 - 0 00.000 1.00014841 0.99996767

6 0510 - 0 00.000 1.00013861 0.99996195

7 0509 - 0 00.000 1.00013961 0.99996276

8 0512 - 0 00.000 1.00014896 0.99996647

9 0511 - 0 00.000 1.00014809 0.99996766

Glen Cameron
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Joined: Fri Nov 08, 2002 12:18 pm
Location: Corbeil, Ontario, Canada


Post by Glen Cameron » Thu Jul 03, 2003 11:37 am

When dealing with UTM coordinates and labling the distance between two points, the scale factor to be used is normally the average factor between the two points or a local scale factor. When working over longer distances, a single factor for the entire job may not be possible.

Glen W. Cameron, C.E.T.
City of North Bay, Ontario

George Huppert

input/ output scale factor

Post by George Huppert » Mon Jul 07, 2003 5:00 am

Just a word of caution, if using grid co-ordinates and output scale factor,if doing a radial stakeout, don't use the radial stakeout icon, it does not apply the s/f. The perpendicular offset does not apply the scale factor.

Glenn Deegan

Distance output scale factor

Post by Glenn Deegan » Wed Jul 16, 2003 3:31 am

I use this feature regularly to annotate survey plans with ground distances from a UTM data base. This feature works fine for lines including short lines in a table. Unfortunatately it does not work for arcs connecting the lines in the table. Can you possibly fix this problem?

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