Can White Balancing be turned OFF with the a900/a8

It could be that the OP had no reason other than curiosity for asking. It seems an odd question from a vacuum, but maybe more reasonable coming from a film photographer, where the white balance is fixed by the medium itself and not a point of discussion until printing... (or, rarely, developing, if you're using alternative film developing methods).

However, at the risk of helping other people who might have a similar question and either don't know why they're asking it or can't put their reason into words, here is one reason one might want to turn off WB altogether, or develop a workaround for WB issues: the JPEG previews are unsatisfying, because they do not well represent whatever's captured in the RAW file. I'm assuming here that the questioner is shooting RAW, because, well, RAW is 100% the first way to deal with WB issues.

Can the WB be turned off? No. But.

One option would be to (try to) ignore the JPEG preview or turn off the display and just pray things come out ok -- i.e. operate it like a film camera. Voila. Problem solved, unless you don't trust the camera or the settings you chose and therefore want to see a visual representation of the exposure captured (wherefore digital photography). When you're shooting the stars at a dark sky site, you want to do this - you don't want your display lighting up after every interval shot, annoying your neighbors and ruining your night vision while you gaze at the stars. Seriously.

Another option is to (try to) ignore the JPEG preview and only look at the histogram (assuming you've gotten used to histogram data and the peculiarities/behavior of the body you are working with, and can visualize how you might adjust the final image in postprocessing - kind of a leap, no?).

Another option is to use the Intelligent Preview function (since we're talking about A900/A850 here), to preview the results of different WB settings.

Another option is to set a custom WB or a preset WB -- e.g. neutral/daylight/5000k -- OR just set the camera to B&W (as has been suggested) -- and again ignore the JPEG output and focus mainly on light/shadow exposure.

Another option is to carry a neutral grey card or a color calibration card, and use that tool to set a custom WB when in challenging lighting.

UniWB answers my question. Thanks for mentioning it.

Jonas A-R wrote: You’re welcome. I think you would have gotten the answer quicker if you had explained why you wanted to turn off wb.

Yep and we did ask.