The position of the target icon itself doesn't make a difference with the jump, but sometimes I found it easier to get the jump direction, timing and/or landing right with a different camera angle (for that particular jump I had the camera straight ahead, IIRC).
A gamepad might make it easier to jump, if you have one, or just a remapping of the keys. For example, from the topic
Sinister Cavern (spoilers):
Changed my "key" commands for the jumping, and it was a lot easier... Now, after I "play" with the chest for a bit....
I move via the "arrow" keys.. I made the " / " key for jumping.....I use my left hand middle 3 fingers to move via the arrows and the little finger reaches the " / " easily.. The mouse does the rest..I've set my "hot" keys to the number pad...so everything can be done, quite easily with the left hand, all in one general area..
I left the Journal, Map and so forth, set the way they were..
Here is a link for a
YouTube video of someone doing this section, or a
longer video (in German), if you think it might help to see it being done.
