Now for the second bit - - -
How many times do I have to state that I did NOT write using F/3.4 at 129mm?
How many times do I have to draw your attention to what was written - - - which was;
"SECONDLY ----- Z O O M the lens so that you can get to F/3.4 and then F R A M E the image the same and make a second shot."
So that means after you take the first shot at 129mm you
zoom the lens UNTIL F/3.4 is available to use - - - that might be at whatever focal length it is - it is the Focal Length where F/3.4 becomes available.
AND then you FRAME the IMAGE the same size.
SO you end up with TWO shots: ONE at 129mm shot at F/5.8 and a second at whatever Focal Length, shot at F/3.4.
And again that is what the majority of this thread is all about . . . the fact that the Focal Length - doesn't matter if the shots are FRAMED the same size.
WW