Automatic scaling of Tracing Image?

[pridbor]

I have imported a known-sized image using the tracing image function, and find that it seems to have been scaled by a factor of 3!?

I would have assumed that it would be imported on a scale of 1:1 and that it would be for me to change scale if I so desired, or where do I go wrong here?

 

[Ken226]

How is the image sized? What type of file?

I believe .jpg, .BMP and .png type files each use a different standard, based on pixels. Alibre probably does not know how many pixels per inch the image file type uses, and assumes a blanket number.

Unless it's a CAD type file that has dimensions associated, you'll usually have to use Alibre's trace image scaling tool to scale it to size .

 

[pridbor]

I just drew a rectangle with known sides and scanned it to a jpg file. I checked it using px/inch and in a photo App where it appeared to be correct.

To be honest I just printed the same image and the same thing happened about 3 times the dimensions. You are probably right that I have to re-scale.

I need to play around a bit more with this feature.

Thanks

 

[Ken226]

I just drew a rectangle with known sides and scanned it to a jpg file. I checked it using px/inch and in a photo App where it appeared to be correct.

To be honest I just printed the same image and the same thing happened about 3 times the dimensions. You are probably right that I have to re-scale.

I need to play around a bit more with this feature.

Thanks

Alibre's trace image scaling tool is pretty quick and easy once you use it a few times.

 

[HaroldL]

If you are going to scan images you might employ the method described by @ReedMikel in this post.

 

[pridbor]

Thanks, Harold for the referenced link, a very clever method!

Preben