The pattern in the first photo looks to be centered pretty well. The second one is just a tad bit "high" on the valve - biased towards the intake ports. Both patterns look awfully "wide" to me. Compare them to the photo I'll attach that shows the contact pattern on my most recent build.
Use those light checking springs and the adjustable pushrod and do an experiment: Mark the top of valve like you have been, make sure the lifter and adjustable pushrod is on the cam base circle (zero lift). Back off the adjustable pushrod so that you know it's way too short. Set the rocker onto the stud, start the nut but leave it completely loose for now, and looking at it from the side so that you can get a good view of exactly where the rocker tip is touching the valve, move the rocker up or down on the stud so that it touches the valve as close to the exact center as you can get it. Hold the rocker in that position and finger tighten the rocker nut down to meet the rocker. Now, continuing to hold things like they are (the pushrod should still be way loose at this point) --- lengthen the pushrod until it seats in to the rocker and takes the slack out. If you did everything right, at this point everything should be snug, all the slack taken out of the pushrod->rocker->valve, and the rocker should be touching the valve dead center on the valve stem. Now "run it through" and see what kind of pattern you get. It'll probably be slightly biased off center - that's ok - what we're doing is establishing a base line starting point to work from. Make some sort of mark, count turns, whatever --- so that you know exactly where this setting is on the adjustable pushrod so that you can come back to it any time you want to.
Now clean every thing up, remove the parts, and LENGTHEN the pushrod by exactly two turns, and make another test pattern. Did it get better or worse? If it's worse, then go back to your baseline setting and then SHORTEN the pushrod by two turns --- better or worse than your baseline pattern? What we're doing here is trying to figure out if "pushrod nirvana" is to be found with a length that is longer than our base line or shorter. Once you know that, then start over - go back to the base line and start running patterns in whatever direction that is that looked better than your baseline (longer or shorter) but making smaller changes - lengthening (or shortening if that's the right direction) by only one turn, or even a half turn --- until you get as close as you possibly can to patterns that look like the ones in my picture.
Here's a couple of tricks that should help you get a better and more readable pattern. I already mentioned holding the valve so that it can't turn. Another thing that helps, is every so often as the valve is opening and closing, stop and 'wiggle' the rocker arm back and forth side to side across the top of the valve. What you're doing is wiping some of the ink off so that the pattern will be more obvious when you next remove the rocker to look at it. In fact, now that I think about it --- it's worth installing a rocker at the baseline length and then doing that 'wiggle' thing to make a marking - then take the rocker off and looking at the pattern without turning the engine over at all --- just to see if your baseline setting really does have it centered and also to see how wide the contact patch is that the rocker makes with the valve. That patch might be 'wider' just from the contour of the rocker tip.
Feel free to holler or PM me if you want to if none of this makes sense. Maybe we can link up or something and I can help walk you through it.
Yes, it's tedious, time consuming, and you may have to make multiple tests at the same settings to get confidence that what you're seeing is correct. However getting this right is important and it's worth the effort.
Good luck --- let me know how it goes.