Sounds like you may have exceeded the camera's shutter speeds at the high end. However, in manual mode it still should have taken the picture.

When in manual mode the camera will insert into the EXIF data the difference between what it meters and what you picked for exposure.

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Joseph K
Seattle, WA, USA

D700, D200, D70S, 24-70mm f/2.8, VR 70-200mm f/2.8 II,
50mm f/1.4 D, 70-300mm f/4.5-5.6 VR, 18-70mm f/3.5-4.5 DX