ABS ripple

Picture?

Picture attached. Look inside of the white lens cap. The wavy pattern is always perpendicular to path of printhead. I did not play with tension arm, because went from 1.73 to 1.73 fillament.

Any ideas?
Thanks ahead.

EDIT:
I am printing on kapton on the mirror with hairspray. The kapton is well attached to mirror, no bubble etc on capton itself. 90 C bed Temp.

Not an expert, but looks like what I get on first layers, where I'm intentionally overextruding (but it sorts itself out on later layers). Perhaps, in addition to adjusting diameter, run some calibration cubes and adjust extrusion multiplier for new filament? .6 sounds large, but if its between your extreme values, it happens in my case (as recommendation goes, trim extreme values from sample and average remaining diameter measurements).

Edit: also, my guess is that nozzle diameter does not matter, you should take error relative to filament diameter (you want the same length of filament to push through the same volume of plastic.. and that would vary in proportion to diameter of filament, independent of nozzle diameter)?

Edit2: If problem was due to severe filament diameter variation, I'd guess you should see issues on vertical walls too, but those look fairly reasonable as far as I can see (whereas mostly consistent over extrusion will affect dimensions, but not cause ripples on small surface areas). Hopefully one of the experts will refute/validate my guesses here. Just my 2c.

I can confirm that it can be the extrusion setting. I'm just posting to help others who might be seeing this thread as they diagnose. It's been driving me crazy. I had been getting beautiful prints and then all of a sudden I start getting extremely severe ripples on the first layer. It seemed to be ok on subsequent layers. I've attached a photo of prints. The lower right photo is of my corrected print using an extrusion setting of 92% instead of 100%.

So, I'm just confirming the good thread above and hope it helps someone else.