III. NEW AND IMPROVED DESIGN FEATURES 15Data Loss ProtectionReliability and DurabilityEase of OperationOne can select either the CF card or the SD card for recording. When the card becomesfull, one switches to the other card. This is not an automatic process so you will knowyou’re now on your “reserve tank.”The intelligent display of the number of remaining shots displayed on the top LCD panelis based on the memory card that has fewer frames left.The red LED memory card access lamp blinks while data is being written to or read fromthe memory cards. Error warnings are displayed on the top LCD panel, in the viewfinderand on the LCD monitor. The shutter release locks. A menu setting permits separatecard formatting. Shooting is possible with only the SD card inserted.Of interest to untold thousands of photographers, even if the memory card slot cover isopened by mistake, the EOS-1Ds Mark II and the EOS-1D Mark II prevent data erasing.Writing resumes when the cover is closed.The Canon EOS-1Ds Mark II continues the tradition, begun in 1971 with the Canon F-1SLR, of reserving the “1” series designation for cameras which represent state-of-the-artruggedness and durability. The use of magnesium alloy is continued for the top, frontand rear covers, the memory card slot cover and the chassis. The mirror box is amachined aluminum die-casting. The dust-proofing and waterproofing seals have beenimproved. There are nearly 100 environmental seal points on the EOS-1Ds Mark II body.L-series lenses add an additional seal at the lens/body interface. Shutter durability hasbeen increased from 150,000 cycles on the 1D, the 1Ds, and the EOS 1v film camera, to200,000 cycles, as on the 1D Mark II. Additionally, the flash accessory shoe has beenstrengthened to reflect the service conditions that the 1Ds Mark II may face.In response to users who had trouble operating the 1D memory card slot cover knobwith gloves on, the shape of the knob handle has been changed on the 1Ds Mark II andthe 1D Mark II. A recess has been created under the handle.Some commonly used functions have been made more accessible than they were on the1Ds. JPEG, RAW and RAW + JPEG can be selected in a single operation and manual colortemperature settings can be adjusted directly with the WB button and the main dial