Mix and Match

OK – its official, just tested it, it works. I was wondering if a Nikon SB-20 (or 28 for that matter would work on a Canon G15)
Why you may ask? Have you seen the Canon 580ex mounted on a Canon G15?

OK, here is the Canon G11 with the 580EX II, the G15 is slightly smaller than the G11! I would guess that the Canon 580EX II is at least 3x larger than the G15. That is why I wanted to try a Nikon SB-20 – much smaller flash. Couple of things here – I wanted a hot shoe flash that was smaller, and that I could bounce and swivel – well at least bounce. Most flashes that do this are certainly bigger than the G15. The second part to this is that I didn’t want to fry my brand new G15! I have used my SB-20 and SB-24 and SB-28 on my Canon 40D and 50Ds, and the research I found showed that the Nikon flashes seemed to work on previous G models…so I went for it.
Works like a charm. Just set the camera on M, and dial in 1/125 and F/4 @ ISO100, then set the Nikon SB-20 at f/4 and ISO100 and shoot away. The shots were properly exposed, as I expected.
Keep in mind that the Nikon SB-20 is about 1/2 the height of a Canon 580EX flash. Here are some dimensions…
Canon G15: 1.6 x 4.2 x 3 inches
Canon 580ex II: 3 x 5.3 x 4.5 inches (directed forward as per Canon’s specs)
Canon 580ex II: 3 x 7.5 x 2 inches (directed up for a ceiling bounce)
Nikon SB-20: 2.8 x 4.3 x 2.7 inches

Here is a Nikon SB-20, it has an odd head on it, but through the cylindrical mechanism it can bounce at a six different angles (-7, 0, 45,60,75, and 90 degrees) and has 3 diffusions/focus designs in the plastic to change the light dispersion pattern from wide to normal to narrow (28mm, to 35mm, to 85mm). If you lay the flash on its back, it is about the same footprint as the Canon G15, but twice as thick. Much better size match!
A little info about the SB-20, it has a guide number of 100 at ISO100 (in feet). This flash can be found for $50-$60 on EBay. Suggested Canon compatible options for the G15 include the Canon 90ex and the 270ex. The 90ex has a guide number of 30, and retails for about $125. It cannot bounce. The Canon 270ex has a guide number of 89 and retails for about $160.00, the 270ex does bounce. If you don’t mind a little less than full auto / ETTL (may require some thinking) then you can get a small powerful flash for 2-3 times less.
So far, very happy with the new Canon G15 – what fun!