Before the mark IV, there was the mark III (now both cameras), before that there was the 6D, and even earlier than that there was the Nikon D3s and the Nikon D700 already on the first shot, DDs are wider and stretch better, functioning ISO is higher, exposure metering is more accurate, and there is no need in changing.
Canon EOS 60D: 18MP CMOS Digital SLR Camera Body - Your Next Photography Companion
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Discontinued Canon EOS 7D Digital SLR 📷 Camera Body Only with 18 MP CMOS Sensor
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Nikon D5100 Digital SLR Camera with 18-55mm VR Lens - High Resolution 16.2MP
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Revamped Sony Alpha a6000 Mirrorless Digital Camera: 24.3MP SLR Camera with 3.0-Inch LCD and Power Zoom Lens
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