Lightroom Export image sizing question

[Rand47]

At our photo club meeting last night, I was asked a question about LR's image sizing function in the Export dialog.  I can "size" an image by dimensions in inches, and at what resolution I desire.  Assuming that I'm "up-sampling" while doing this, what "method" is being employed by LR in doing the up-sampling?  I had no idea!  (Big surprise - NOT).  Any of you know?  Is it the same as the print module is using when doing an "on the fly" resolution increase based on image size on the paper?  Or, is it using one of the image size up-sampling options available in Photoshop?  Or is it something else unique to Lightroom?

I'd like to be able to provide an accurate answer for the "troops" in the club.

Rand

[digitaldog]

LR uses a very good adaptive Bicubic interpolation in a linear color space. It isn't identical to PS! Interpolation up or down can also be combined with a few output sharpening options based on the pixel dimensions too!
Now ACR within Photoshop operates like LR in the above respect.

[Rand47]

LR uses a very good adaptive Bicubic interpolation in a linear color space. It isn't identical to PS! Interpolation up or down can also be combined with a few output sharpening options based on the pixel dimensions too!
Now ACR within Photoshop operates like LR in the above respect.

Andrew,

Thanks so very much!!!  You da man...

Rand