Importance of horizontal vs vertical RF alignment

How important is correct vertical alignment for an rf to achieve correct focus?
My Agfa Optima 1535 was correctly aligned vertically, but not horizontally so at infinity the horizontal alignment never lined up (looking at the moon for closest to real infinity that i have). This resulted in images that would back focus i.e. the camera hit focus behind my intended point.
I can adjust the rf so that it is aligned correctly in the horizontal axis, but this has knocked off the vertical alignment. While this is annoying, does it actually matter as long as the horizontal alignment is correct? I have a test roll of film in it right now to check.
I have a Leica 50mm DR with the incorrect goggles for close focus (there were two types). That cause the same alignment issues when using the goggles, but as long as I align it correctly on the horizontal axis, the focus is correct in the image.

(question also asked on RFF)

I think as long as the vertical alignment doesn't bother you (to much) it doesn't matter. Horizontal is what really counts. My Canon P is very easy to adjust both vert and horizontal.

Agreed. It is not such a big deal as long as it does not bother you. One of my Canonets has this issue and it hasn't caused any harm. The only case when I think it might be an issue is if you're trying to align the spot with a diagonal line (maybe?).

For me both have to be fine. One affects image sharpness, another affects visibility. If image is not collided vertically, it is kind of blurry to me.

Both are required for critical focus. Set the vertical alignment first, then set the horizontal alignment. Vertical misalignment will cause an error in rangefinder accuracy as distance increases from the "zero-crossing" where the rangefinder measures the correct distance. Think of the vertical misalignment creating a different slope for rangefinder coincidence versus distance.

With a slower lens, the error in focus might be covered by DOF. Some mechanisms are more sensitive to errors than others. The Vitessa drove me nuts. Worst rangefinder mechanism ever made.

BrianVS said:

Both are required for critical focus. Set the vertical alignment first, then set the horizontal alignment. Vertical misalignment will cause an error in rangefinder accuracy as distance increases from the "zero-crossing" where the rangefinder measures the correct distance. Think of the vertical misalignment creating a different slope for rangefinder coincidence versus distance..

Click to expand...

Yup. Found that out with my last roll in the camera...

I feel your pain- I learned about this in the original Nikon SP and Retina IIIS repair manuals. I've done this on the Retina IIIS, SP, S3, S2, Canon IIF, Canon P, and others. It's not hard on any of those. On the Vitessa, HARD!!!