Andaman Sea Blackwater

Barmaglot_07 wrote:

gokhankuzu wrote:

TTL is useless in those dives, focus light or torchlight will mislead TTL.

On the opposite, TTL is quite useful when you're dealing with subjects that can be translucent (need lots of light) or reflective (need just a little light), and you have no time to play with the settings.

TTL is good, but your focus lights and other all light must be turned off when flash firing, otherwise, it will be overexposed. For real TTL you have to use sony flashes in the housing with full electrical connection.

But this is a night dive and the f value is definitely wrong and also iso value. You should take the photo the moment you focus on it. f8- max f11 and iso 100 will give you incomparably better results than f25 and 800.

As I said, prove me wrong. Hop over to Florida, go on a blackwater dive or three - plenty of operators running them there, - then post your images taken at f/8 and ISO 100. My experience is that without extra DoF buffer afforded by small apertures, subjects will move out of focus during the fraction of a second it takes to pull the trigger, lens aperture to stop down, and optionally the strobes to fire a TTL metering pre-flash. Consecutively, a small aperture at base ISO values ends up needing more light output than the strobes can supply, hence the increase in ISO. My setting of 800 was indeed somewhat higher than needed, as I had misremembered a certain feature of my camera - for me, using a Sony A6300, the optimal ISO value is 400.

You don't need an extra dof. The dof of f8 is even too much for the objects in your photos. You will only shoot the moment you focus on it. No waiting, you have to hunt the image. The moment the object moves out of focus, the dof does not capture it in the right focus. This thinking is wrong. Even if it stays in DOF, the object cannot come out clearly. You are there, try it and see for yourself and say I did, look what happened.