Very early stage of blossom end rot (BER). only the skin is affected. Will be slightly thickened but, typically, the flesh below is fine.

See the link below -

Here is a link that might be useful: the FAQ w/ info re BER

This post was edited by jean001a on Sun, Aug 24, 14 at 20:07

probably stink bug damage, not BER.

Not stinkbug. Early BER.

See link -

Here is a link that might be useful: stink bug damage

This post was edited by jean001a on Mon, Aug 25, 14 at 2:27

BER on tomato fruit
see link from Cornell -

Notice in the image on that page, the center fruit in the 2nd row.

Here is a link that might be useful: BER

This post was edited by jean001a on Mon, Aug 25, 14 at 2:32

More variations on BER
see link -

Here is a link that might be useful: variations on BER

Thanks. I do believe it is early BER since it only occurs on the blossom end and I have found some with full BER. I will have to condition my soil better for next year.

Blossom End Rot (BER) generally initiates from the point of blossom. That point is like human belly button. When the fruit cannot close and seal it, air and with it bacteria get in there and start rotting.

see a typical BER in this image.