Originally posted by MJKoski It does not skip anything if I select minimum delay between the exposures in the options. I just set number of photos and I get that number of photos with any exposure time up to 30 seconds. Setting a delay of 1s or more is guaranteed to mess star trail stack so I have to use that minimum option. That is very nice but the minimum delay is not consistent - it sometimes causes multisecond delay - and star trail stacks do not form 100% perfect trails. Possibility to use longer than 30 seconds per exposure would make things easier for storage space as well. I would prefer 60s x 60 stack instead of 30s x 120 stack.
I use "minimum" for stacked star trails but have not seem any evidence of variations -- certainly nothing like a occasional multisecond delay. That said, the minimum delay would vary if the SD card wasn't perfectly consistent in how long it took to write each image. An unreliable card or one that had not been formatted prior to the series might show variations in writing time. Or if the images vary in amount of detail due to clouds, light painting, etc., then shot-to-shot write times would vary and the minimum time would vary.
The overall point, though, is that there's no easy way for Pentax to force a consistent minimum because the minimum is at the mercy of the SD card.