A cm of fine, black compost--lots of biological activity--would also help it. A bit less feeding needed that way, too.

I agree with above. The lawn just needs a little love. It looks very compacted so giving it fertilizer, compost or even water is pointless - it can't peculate down to the roots. A spiked aerator would be useful for this or a pitch fork to poke holes into the ground. This action would send water, air, fertilizer & compost to the roots - and food for the earthworms that will do this back braking work for you.

Sorry, I wasn't complete enough: I was figuring on compost right after spiking.

Thanks for all the replies the last 2mornings have been very frosty so I will get the fork out hopefully at the w/end and sieve some multi purpose compost over it weather permitting