# error in online reference?

https://support.pix4d.com/hc/en-us/articles/203576115-Relation-between-the-Printing-Scale-and-the-GSD#gsc.tab=0

say:

Example:  When the orthomosaic is printed in scale 1:200, it means that 1 cm in paper represents 200 cm in reality.

The printing scale indicates the acceptable error that a printed orthomosaic can have. The acceptable error is based on the smallest difference that a human can distinguish at a drawing, which in a scale 1:1 is about 0.25 mm. This error should be multiplied by the printing scale in order to calculate the acceptable error that a printed orthomosaic should have.

Example: For a printing scale 1:200 the acceptable error is 0.25 * 200 mm = 50 mm = 5 cm.

in the beginning say 200 cm but in the end say 200 mm…so the calc is wrong…i think…

Hi Marco,

I think that these are two different examples. the first shows the principle of printing scales, so with a scale of 1:200, 1cm corresponds to 200cm. and the second is to show the acceptable error you can have in your printing with a scale of 1:200. the acceptable error in a scale 1:1 is  0.25mm so for 1:200 it is 0.25mm * 200. This is used in the next example in order to know what GSD to choose for a project.

Hope it helps!