Lens, body or me

Here’s a couple from the Ulster Grand prix, last weekend. Billed as the fastest racing in the world. Lots of pics of part bikes only as I struggled to get them in shot. Processed with DPP and not cropped.

This was taken as the bikes were approaching at a considerable speed. I was close enough to have reached out to touch them. Not really the safest, but quite exciting, or perhaps scary would be more appropriate.

Canon 500D, 1/2500. F5.0, ISO 800. Single point servo AF, centred on the no.5 helmet. EF-S55-250mm at 131mm.

And this was taken from the inside of a corner. Again, pretty close and the speed was considerable and I tried panning. This was later on and the light had faded a bit. Canon 500D, 1/1600. F5.0, ISO 800. Single point servo AF, centred on the petrol tank.. EF-S55-250mm at 55mm.

Any thoughts on how I could improve?