Do these look ready ?

The last pic looks like some foxtailing going on, new growth starting from a more mature bud, usually caused by heat stress or light being too close.
What type of lights being used? How close are they to canopy? What's the temps and humidity in the room?

 

What Are Marijuana Foxtails? Is Foxtailing on Buds Good or Bad? | Grow Weed Easy

 

Looking good mate! The distance, temps and humidity look pretty good to me, yellowing of the leaves towards the end of maturity is totally normal. They actually look pretty damn close, but there's no way for sure without looking at the trichomes with a loupe or microscope really imo. That third pic looks like all the calyxes are standing straight up still, which would be a sign there not mature yet. But I'm just a noobie as well, so I'm sure there's some more veteran growers that know better than I. Lol How many weeks since switch to 12/12 and what strain?
Check out this link, some great info on harvesting.
When is the Best Time to Harvest Marijuana Buds? (For Highest Potency) | Grow Weed Easy

 

My first grow, just going into week 9 from switch to 12/12 today.

 

I'm in the same boat as you mate, I'm just entering week 9 and are wondering the same as you, mine are mostly clear still and will post some pics later when I get home.
Yours seem to be getting a little cloudy with some clear, it's hard to tell sometimes I'm thinking. I was always told to look at the trichomes in the buds more than the sugar leaves, they tend to turn a little quicker. If you're like me, I'm going for the more uppity buzz, not couch lock, so not many turning amber.
Check that link I posted on harvesting, there's some good pics showing the difference between clear and cloudy.
How many weeks at 12/12? What strain? Sativa, Indica? Hybrid?

 

U are so right on the heat stress. If ur pistols all turn red and receded and u don't have amber than it wont. Take a nug that looks done dry it and sample for thc not taste. Do u have a loop. If thrics are milky at least u will be ok. Does it have the smell? That also gives u an idea if it's ready enough

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yep i agree with @Papa Puff just take a small bud dry it quickly over a day or two then try it ,,the taste wont be as good as its not been slow dried and cured ,,but it will give you a high/stone thats not really affected by drying quick ,,,if you like the high and stone flush,,,mac,,

 

hi there so you liked the sample you took off the plant ,,,now just think how tasty ,and how the high/stone is going to be after you flush and dry then cure for a month or so ,,,it'll be great ,just take your time drying and curing,,mac,,

 

Right on

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