Project 6: fitting the frame to the subject

I decided to use a jar for this project. I was having problems trying come up with suitable subject.
My first photograph was taken without too much thinking about it. The othe threephotographs I took more care over.

1st photograph
ISO 200, f/3.5, 1/20 sec.
18mm.

2nd photograph
ISO 200, f/5, 1/20 sec,
40mm.

3rd photograph
ISO 200,f/5.6, 1/20 sec.
48mm.

4th photograph
ISO 200, f/5.6, 1/20 sec,
55mm

I liked the 2nd and 3rd photograph the best. The 4th photograph just filled the frame too much for my liking.