The importance of doing your homework cannot be underestimated. I visited my client for a September Sikh wedding yesterday and, in addition to discussing their requirements, we also checked out locations for the group shots and the temple itself. In particular I was able to check out the lighting in the temple, clarify where I was allowed to stand & ask whether flash was permissible. In short I’m allowed to go where I want to provided that I do not turn my back on the Holy Scriptures and I can use flash and “whatever else I need”. I can even go onto the raised area with the Scriptures, provided that I remove my socks. I have to confess that I found the whole thing quite refreshing! In terms of the temple, there’s highly polished marble everywhere (it’s the largest Sikh temple in Europe) including the ceiling (a fairly neutral grey / brown). This would suggest that bounced flash could be pretty effective with less light loss than normal. I took a point & shoot to check likely exposure. 1/10th @ ISO 50 f2.8 was the typical worst case scenario. This equates to 1/40th @ f4 ISO 400 or 1/80th @ f4 ISO 800. I see two options here. I can use my 18-70 f3.5-4.5 or 28-105 f3.5-4.5 on a D80 (for a bit more reach) together with bounced flash, and shoot at around f4, or I can use the Tamron 17-50mm f2.8 at f2.8 without flash, but at the expense of reach in certain situations. Suggestions / advice welcome!