Brown spots on potato leaves???

Thanks for the suggestions, its really appreciated. 

I have given them a feed with Magnesium in it, just in case.  Also I have been removing leaves as they appear incase its blight.  Although the once overflowing very healthy plants are looking rather sparse now.

Went out for a leaf inspection this morning and saw a uniformly green capsid bug on there!!  In one day, about 20 leaves have spots on them and I am worried about removing anymore leaves especially since this was a blight precaution.  However if it is blight then I would continue the removal to stop any spread.

Would capsid bug damage be this severe so quickly?  Thats alot of leaf damage for one day.  If it's possible this is only capsid bug damage, I presume I stop removing infected leaves and spray a bug killer?

I read they like especially like fuschias but mine are ok.

I thought the leaves in the picture were bronzed and thought of spotted wilt virus

The whole section of stem seems to get the spots one day and the spots increase in size and number as the days progress. 

The colour tinge on the leaves is due to a fungicide I put on them for blight, maybe a vain attempt at trying to save them.  This container has 4 tubers in whose leaves are all infected with these spots.  If I leave the leaves on, they go like the picture above but if I remove them, no leaves will remain on the plant.

On the other side of the garden two more containers have started displaying brown spots on leaves but are not spreading as quickly as this container has.

I was thinking of leaving this container alone and seeing what develops to see if anyone recognises what is going on to save this from happening next year.  Is this a good idea or should I just kill this plant off to help contain the spread (although its already got my other tubers!)??

An update    Kept on with the plants regardless of the brown spots.  Have now harvested one container.  Some of the potatoes have like a scab on them.  Does this give a clue as to what is going on? 

Common scab, it's errrm, quite common.

Here's what the RHS have to say.

http://apps.rhs.org.uk/advicesearch/Profile.aspx?pid=230

It doesn't - the two are unconnected.