Shot advise. Scaling out to act as camera ascent

[Lee M]

I have a shot that requires a camera to move down a slider on lets say a 25 degree angle to get a closeup of the subject (birds eye) BUT THEN it is supposed to ascent straight upwards on a 90 degree angle preferably in the same shot. Obviously it would be difficult to do this on the slider. Now I am pondering if I kept the slider flat and high up towards the roof instead of having it tilt downwards then I can scale in and out of the subject by recording in 6k and editing in 1080p.

Is this common for this type of shot? I am assuming I would not lose any quality since its essentially cropping the 6k footage to 1080p and then scaling back to 6k. I guess my main concern is it not appearing obvious to the viewer that the camera is not actually moving downwards/upwards. Was actually hoping to do the final editing in 4k but I am guessing these scene would require it to be in 1080 to not lose quality. Perhaps I should borrow an 8K helium for this shot so I can keep everything in 4K?

Any advice would be great.

 

[Todd T]

I would shoot a few scenes of the birds eye view at various "heights" and use them as a matte for the slider shot. that way you can scale things down to simulate the ascent.
Take a look at this video as an example: