DRK-1 Dark Eye Probe

[kresty]

That's about what I was guessing just from the video - "softball size" is what I was thinking - which looking up on the 'net seems to have a circumference of 12" (why do they specify circumference?) So about 3.8" diameter. So I guess we're in the same ballpark.

It's hard to get excited about the Wookiepedia entry without a source, and, as you mentioned, they didn't say what bit was being measured. Interesting, they link to the IM droid in Tokyo Star Tours - that one's clearly similar, but the "skid/fingers" on the lower sides differ. (I mean, lots of stuff differs, but those look like they should've been the same as the CG DRK1 model.)

[kresty]

Ok, I'm reconsidering...

It's on https://starwarsscreencaps.com/star-wars...e-1999/34/ and https://starwarsscreencaps.com/star-wars...e-1999/36/ and
https://starwarsscreencaps.com/star-wars...e-1999/50/

In that last set its occluded by Darth Maul's hood so it's further from the camera, yet it's about the size of his head:

DRK-1 Behind Darth Maul
Here the Dark Eye Probe is behind Darth Maul's hood - so further from the camera, yet still appears about head sized.

And again here in town (second link above) it goes behind a humanoid head - again about head sized:

DRK-1 Occluded
This shot makes the DRK-1 appear head-sized or bigger.  It's behind the humanoid character in town.

Not a great shot in that last, and I don't have the disc right in front of me, but it seems like he's substantially bigger than I'd thought.  

That would be more in line with a .3m (almost 12") height excluding the antenna.  Maybe including the cameras.  50th percentile human head is about 9" from bottom of chin to top of head - but Darth Maul has extra stuff to make his head taller, and the other -whatever-it-is- is wearing a helmet.  50th percentile widths of heads are 6".

So a .3m main body height might be plausible.  I suspect, however, that someone pulled it out of thin air when writing specs for a book or something, so I'm not sure that's very accurate.  Maybe including the lower camera?

I think 9" is probably close to the lower bound.