The big kahuna in my camera arsenal is the Canon 5D Mark III packing 23 megapixels and 14 stops of range. It’s a beautiful pro camera that shoots to both SD and CF cards and sports advanced control functions and other features as well as superb noise handling into very high ISO ranges.
The other item that is almost always attached to the 5D Mark III when I don’t need a flash is my Canon GP-E2 GPS receiver. The GPS unit is very quick to acquire signal, establish a location down to within a couple meters, indicate shooting direction with the built in compass and automatically set the date and time in the camera so it is always precise.
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Canon 5D Mark III
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Left View
The battery grip visible in this photo is the Vello BG-C9 battery grip. I would argue that Vello is the best non-brand accessory manufacturer I've ever used. Their prices are reasonable but their products are excellent and robust!
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Rear Profile View
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Canon GP-E2 GPS Receiver
Here's the GP-E2 in all its glory, the unit is accurate down to within a meter or two and also packs a compass so you know what direction your looking when you take your photo. The best feature in my opinion is that it automatically sets the date and time in the camera so it's always accurate right down to the second.
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LCD Panel
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LCD Screen & Controls
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Manfrotto Tripod, Three Position Head & Camera