What is 15r error message for Nikon D300? - Nikon D300 Digital Camera

If you turn the camera off and then back on and the mirror is up. The camera needs service.

Is this preventing you from shooting? Normally the r-number merely indicates how many additional shots you can take in the current burst before the buffer fills. It's strictly informational, and should not disrupt your shooting (until the number drops to zero and the buffer fills, at which time the camera will slow down while it transfers the pictures from the buffer to the memory card).

Turn the aperture ring on the lens to its smallest setting (largest f/number) and then forget it's there. You can control the aperture from the camera body, the same way as on lenses without an aperture ring.

You didn't specify which Sigma 70-300mm lens (Sigma has at least five different versions, and I'm not referring to the lens mount), but from the error message I assume the lens has an aperture ring. Turn the aperture ring to its smallest setting (largest f/number) and lock it in place. Control the aperture from the camera, the same way as on a lens without an aperture ring.

If the lens doesn't have an aperture ring, please reply to this post specifying the exact model of the lens. That's all of the numbers and letters around the 70-300mm, like AF, DGO, f/4.5, etc.

CHA error message means that the memory card is unusable. You should format the card by inserting it in a card reader or try another card.

Let me know if you need more help,
Sai.

Were the pictures shot in "raw" format?

try the last card you had in it before this problem occurred sometime the processor in the camera doesn't realize the disk is gone sort of like your computer once it starts reading a disk and you remove it half way threw the load. Well usually before yu can go any further on the computer you must put the **** back in and close the program out. This issue is usually case on cameras when the disk is removed before the camera is turned off.

Hello,
Download Nikon D300 English user manual from Nikon Support.
Regards,

Did you update Adobe Camera Raw when you got your D300? The D300 shoots in a newer version of NEF.

Yes, all D300 makes this noise when the sensor is being cleaned.