Owner contribution
I have always liked travelling light with just a camera and single lens so when I recently purchase a Tamron 70-300mm VC lens I required something a bit larger than my lowepro tlz 20 holster bag. The problem is that the lens is 15cm long alone so would need quite a deep shoulder/holster bag. The ideal candidate looked like the Think Tank Photo Holster 20 bag. It can be extended to accommodate not only this lens but also the hood attached. So I have the best of both worlds, a medium sized shoulder/holster or an larger one for the longer lenses. Overall a very nice bag at a reasonable price considering its quality. It feels very well put together with strong materials and parts. There`s ample room for most cameras and lenses and with the extendable "pop down" section with a spare divider makes it useful to carry not only longer but also 2 small/medium sized lenses aswell. It does perhaps have a slightly boxy, ungainly feel especially when used as a holster and extended. But I guess that`s to be expected for a holster of this size. I`ve used 1 body 1 lens holster/shoulder bags from Lowepro, Tamrac, Crumpler and M-Rock. But I havent come across one that is as well constructed and designed as the Think Tank Holster 20 bag. Fully recommended!
What works
Strong materials, extendable base, soft dividers, small pockets for storage. Smart design.
Room for improvement
Slightly boxy , awkward feel when used as holster and extended.

