last night I took some night sky shots, and I've noticed that with long exposure times [15s;30s] the time it took to store the images in the camera memory card (jpeg) took roughly as long?
Whilst the file size is fairly small at 1 to 3MB / file.
Any idea why this is?
iso were between 200 and 800.
EDIT: thank you for pointing out the Long Exposure Noise Reduction functionality, this indeed explains the extra time taken after the true exposure.
Noise reduction will be automatically activated when noise is detected in any exposure over one second. Noise reduction is subtractive, so after the initial exposure, a second exposure of identical length is made with the shutter closed. Noise from the second exposure is subtracted from the first image leaving a pristine, noise-free image. The only downside is the exposure takes twice as long.