Waist is 526mm from the second lens, L3.
| (mm) | Current Layout |
| L3 | 0 |
| BS2 | 120 |
| M9 | 130 |
| WFS1 | 123 |
| L3 to WFS1 total | 373 |
| L3 | 0 |
| BS2 | 120 |
| BS3 | 302 |
| M10 | 142 |
| WFS2 | 115 |
| L3 to WFS2 total | 679 |
| diff | 306 |
| Rayleigh length | 153 |
| waist from L3 | 526 |
IMC WFS.
Also just to clarify, these are measurements I took from the IOT2L table this morning.