Originally posted by gwoodward If I use my 55-300mm DA APS-C lens on the K1 in Crop or Auto Mode the image fills the sensor
In crop mode the whole of the sensor is not used, only an aps-c-sized portion of it. That portion has 16MP
Originally posted by gwoodward It seems to me that if I were to use the lens in Full Frame mode then crop afterwards, I will get the full detail of the 32 (36MP) megapixel sensor in the cropped image rather than 15mp
If you crop in PP your final image MP count will depend on how much you crop. If you crop to the same size as the aps-c mode image would have given you, you still only end up with 16MP.
Think of it this way...... The magnification of the lens is identical in both modes. Let us say there is a house in the centre of your scene. That house may cover 5MP on the sensor. It makes no difference whether you use FF or aps-c mode, the house will still be covering 5MP