I guess it's a primeval thing, to go out to seek and find at night, who knows? :lol: Seriously, the main reason is to search and items when there is least traffic and more chance of finding something, before the possibility of other detectorists finding dropped item in the early morning or the following day. There are less distractions, allowing me to concentrate purely on target tones, I also find it a good release, a form of relaxation if you wish.
When detecting with the Ace 250, I am looking more for recent drops and the odd item regurgitated by the erosion of the beach. Since the detection of objects is limited with the Ace in wet sand, I mainly concentrate on dry sand and damp sand down to the low tide mark, reducing the sensitivity down to about third to cope with the salt, hence dropping depth capabilities down to only several inches in depth in the wet sand. No real need for a pinpointer in wet sand, just use the scoop, recheck the hole to ensure the target has been removed, then use the pinpointer to rummage through the excavated sand. As you may know, the pinpointer, when used in wet holes with collapsing sand, tends to false on all the salt water, hence making the pinpointer near useless.
On the other hand, when I take the Infinium out, I purely go down at times of low tide at night, exposing the sand bars, gullys and ripple strips, prime ground for a PI detector to find those deep heavy objects that are unable to be detected by the Ace. Also low tides on a full moon tend to be significantly lower than at other times, alowing access to ripple strips that are usually obscured by water. Another plus is the moonlight, which enables excellent vision when working the beach, with resultant shadows making it easy to grid up sections of the beach and cover every square inch.
As I do contract work, I can afford to spend extended times out at night, allowing for a sleep in the next day,and to attend to other duties during daylight hours. I am also a bit of a night owl, so late nights don't faze me.
As for identifying targets in wet sand using the Infinium, same deal as the Ace, pinpoint the target with the detector, use the sand scoop to dig on and around the target area, recheck the hole and excavated sand for the target, and keep scooping if it is not located. I have learnt to pinpoint pretty good with the Infinium now, and also going by the strength of the signal, I generally get a good idea of the likely depth to the target, something you learn after digging many a target, both good and bad. So I basically stay out of the surf at night and purely stick to tidal flats. Also having a fully water proof detector allows you to pretty much drop it anywhere when digging targets or having to accidentally drop it in the water.
I usually arrive as the tide is on its way out, allowing a decent window of opportunity to cover some ground. When the tide does come in, it usually does so pretty quickly, then I tend to venture from the tidal flats, up the low tide line, and cover the dry sand, gridding up the beach to ensure I don't miss anything.
I could image it would be a completely different scenario down Victor way, with rocky flats to deal with, and many trip and other present hazards (crabs etc) vs nice clean sand to dig through.