Today I did something silly.
I thought I'd try the Tamron-F 1.4 TC on the bigma.
When I got to the park I found the Black-shouldered Kite in a low tree about 10 metres from the path.
The auto-focus wouldn't work and the viewfinder was so dark I couldn't see to focus manually.
So I had to take the TC off and stuff it in my pocket, I didn't take any caps.
But that wasn't the silly thing, it was that I didn't test it at home first.
Anyway, with the K3 and Bigma alone, a 100% crop.
The DA*300 + TC would have been a better choice.