Difference between strobe and in built flash?

[SeaHound]

Hi,

Just getting into underwater photography. Can anyone please explain the difference between in built flash and exteral strobe light?

 

[jeraldjcook]

The main difference is strength. An external strobe is many, many times more powerful than the internal flash. Water sucks up light and the internal flash is good for only a couple of feet. There are other benefits, but that's the main difference.

 

[alcina]

An external strobe gives you a great deal of flexibility.

The most beneficial thing with an external strobe is the ability to move it. This is how you reduce backscatter in your images and create better lighting of your subject.

Extra power and controllable power are also benefits.

 

[oly5050user]

Alcina said it all..

 

[Kim]

If you shine a torch at a mirror in the dark you have a chance of reflecting the light back into your own eyes and blinding yourself. That's like backscatter. When a flash source is close to the lens it can reflect directly back from particles in the water (that we normally don't even see) and the picture ends up with loads of round blobs of white light of varying intensities depending on how much light was reflected back.
By using a strobe positioned off to one side, away from the lens, the reflected light path bounces clear of the camera lens so you don't get those spots...the backscatter. There is a bit of a learning curve involved with strobes though...... how much power to use.....aiming them correctly. If you have a system that can directly connect ettl through the casing between camera and strobe - like the Ikelites do - then the power settings become automatic. You still need to point them at the right place though.

If you ONLY have an internal flash....getting very close tends to reduce backscatter, but some cameras have issues with shadow as well, if the case blocks the internal flash in part of the area.

 

[D_B]

Kim has a good discription

I'll try another
take a flashlight in a dark room, and pound on some furniture and watch the dust in the light beam, hold flashlight in front of you and now think of taking a picture through that of what your light is shinining on (the wall) .. you would have all sorts of dots in front of the subject ~ backscatter
now hold flashlight at arms length out to your side and illuminate the same spot, now the dots are all off to the side and only dark is between you and the subject ~ no/less backscatter

 

[SeaHound]

Makes sense! If someone is getting into u/w photography. Do you guys think it would be a good idea to start with a strobe or to perfect technique with built in flash and then buy a strobe?

 

[RonFrank]

Internal flashes have a number of issues.

They drain the camera batteries.

They cause redeye (topside) and Backscatter (UW).

They are generally inadequate for shooting at a reasonable aperture, and ISO.

They can not be positioned.

The only upside of built in flashes is that they will allow one to use the camera's flash TTL capabilities.

I would suggest that an external flash is the best option even for a new UW photographer.

Now for the tricky part! Which one?

 

[oly5050user]

Makes sense! If someone is getting into u/w photography. Do you guys think it would be a good idea to start with a strobe or to perfect technique with built in flash and then buy a strobe?

Why waste time, go straight into a strobe and wide angle lens..

 

[Nocturnal Lights]

What kind of camera/housing setup do you have?