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Proportion between pixels and meters? post and replies

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How can I view the meters per pixel?
Noel Colon
1 Posts

Dear Douglas,

I would like to know if there is a way to find out the exact number of meters per pixel on Tracker after using the calibration stick, since it's part of the data required for my physichs assignment.

I believe I could calculate so by dividing, for example, the difference between the x position in meters and the x pixel on two different tracking points, but I do not know how accurate it would be.

Thank you for making this great software and assisting us since 2009.

Noel.


Replies to How can I view the meters per pixel?

Re: How can I view the meters per pixel? -
Douglas Brown Avatar
Douglas Brown
450 Posts

Hi Noel,

Yes, you can get that number exactly as you described: (x1 - x2) / (pixelx1 - pixelx2).

It's overkill and meaningless to report that number to super high precision because of the uncertainties when marking points. But if you do want to see the full-precision values just select the rows of interest in a table, right click the table and choose Copy Selected Cells|Full Precision.  Then paste into a text document or spreadsheet to see the values.  Doug


> I would like to know if there is a
> way to find out the exact number of meters per pixel
> on Tracker after using the calibration stick.
>  
> I believe I could calculate so by dividing, for
> example, the difference between the x position in
> meters and the x pixel on two different tracking points,
> but I do not know how accurate it would be.



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