S log 3 looking white

S-log3 is at times problematic, due to yes, the potential noise floor issues. What is needed is more perhaps of a precise exposure than a "brighter" exposure. You do have to make sure your shadows are lit within the capability of the camera to handle between "middle gray" and dark-ish but still detailed. Or that dark-ish/detailed area will be very noisy.

So making sure the scene contrast is within camera capabilities is possibly the thing to worry about when shooting with S-log3. That gets you the best of all possible results. Decent noise and shadow levels, and plenty of sofly rolled off highlights.

The camera makers design and "sculpt" their log encoding for correctly exposed scenes. It will not help to over or under expose the recorded image... either way you lose data.

Yes, some on YouTube suggest that by "over-exposing" everything ...including log files ... you get Nirvana somehow. The advice is worth exactly what you paid for it.

I have had 40 year of professional imaging ... getting the parts of the image you are most concerned with properly place in the capture media's (film or digital) recordable range is the only way to get the better quality image. Period.

And now, I work for/with/teach pro colorists ... so I spend most of my online and at-event time with them. Some rather noted ones too. They are totally disgusted with most of the Youtube garbage on "properly exposing X!"

Paraphrasing a common comment from Walter Volpatto, ' ... at least the directors and DOPs I work with know how to use a light meter, a field monitor, and test images so I don't have to mess with that crud ... '

And most colorists are totally down with that sentiment.

You want an image with the key parts well above the noise floor, but not to the point you clip highlights. Which often means you need to have supplemental lighting to control the depth of shadows so you can also protect the highlights.

That's ... how it works. Properly.

I dont use s log 3 but shooting over exposed does not sound right to me.