Generally, there are three methods I use to figure out if the hops are ready:
Feel: do they feel papery, springy? I know this is hard to describe, but they shouldn't feel "wet". When you squish them, they should sound rustle. Gently part the cones. Do you see lots of yellow powder and is the powder golden?
Color: A little browning is good IMO.
Smell: This is probably the biggest one. Young hops tend to smell like garlic and onions. When it closer to the time I expect to harvest, I will smell the cones daily. You really do start to notice a difference! Over time, the garlic dissipates and you start to get the characteristics of the hop (citrus, tea, earthy, hay, grassy)
Those look good though