I went along to the special exhibition at the National History Museum this morning. I think it was well worth the entrance fee (5 quid plus 1.50 booking fee). They sell tickets against a time slot but once you are inside you can stay as long as you like. I got a ticket for the 10.00am slot, the first of the day, and spent about an hour and half there. It is hot and humid so you have to wait for your lenses to de-mist. There is a maze as part of the exhibit, but you can skip that if you want (I did). The other advantage about getting there before 10.00am on a Sunday morning is that there is plenty of free parking in the streets by the museum. Of course if you do not want to drive, South Kensington tube station is right by the museum as well. The exhibition goes on until mid-August.
BTW - when I got out I soaking wet from sweat

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They do not allow flash photography so you really need a sunny day as sunlight is the main source of light. I opted for ISO800 but even then I could have done with more light as f2.8 is quite often too shallow a DoF.
Anyway, here are some of my better shots taken using my Sigma 150mm and D300. There are a loads more on my flickr site
HERE
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15) One of the front of the museum taken with the Nikon 50mm 1.4
Click on any picture for a larger version.