TTL or manual

I'm still vary new at underwater photography and have found when switching my Ikelite housing from TTL to manual with the camera set to AV the shutter speed defaults to 1/200 with strobe set to manual at full-1/2 power my pics are amazing. only adjusting the aperture between 16-22 for macro this works grate for small fish darting fish in and around the reef not that one would need such a fast speed for those fast moving nudie.

It has taken me a while to learn this trick I was always using my camera/strobe on TTL and what happens is with the right exposure and camera set to AV the shutter speeed was to slow.

so I would like to know what most people shoot TTL or manual for macro/wide angle and why??

I use a Nikon D80 in an Ikelite housing and I am just getting used to having TTL again.

Not familiar with the Canon but it sounds like with the flash set to manual the shutter is set to the flash sync speed but when the flash is set to TTL the shutter speed is set to expose the background with the available light.

For macro I'm using the flash on TTL, the camera on manual so I can select a suitable shutter speed to expose the background or black it out as I wish. I set the metering to spot so that the flash exposure is only exposing for the subject and not trying to light the background as well, as it can tend to do on matrix metering. TTL handles this type of shooting very well.

For wideangle I'm going to experiment with TTL but it's likely I'll revert to manual for some, possibly all shots. With wideangle it's probable that you're trying to expose using available light and just using the flash to light something of interest near the camera. TTL doesn't always get this right as it can overexpose the subject while trying to light the background. For wideangle I've played around with P mode on the camera and matrix metering to expose the whole scene while manual flash picks out my main subject. This was on a D70 without TTL so as I say I'll give TTL a go to see well it works on wideangle.

Hi Indoman and welcome to Wetpixel.

It's important to understand that there are two meters in your camera. The exposure meter and the flash meter. When your camera is set in Av mode, the camera uses the exposure meter to set the shutter speed.

When you connect a flash, the camera comes from the factory set up to default to 1/200th (the fastest SS you can use w/ flash connected). You can go into the Custom Functions on the camera and there are two choices, 1-default to 1/200th or 2-not default to 1/200th). If you take it off 1/200th then the camera in Av mode uses the EXPOSURE METER to set the shutter speed.

Now - what does the flash meter do? When you have an eTTL flash attached and use eTTL the flash meter tells the flash what power to use. The flash meter, TTL, etc has nothing to do with the shutter speed. All you need to know here is that the maximum shutter speed you can achieve is called the flash sync speed and is 1/200th on the most of the Canon DSLRs I believe.

Cheers

James

Thanks James/kenbyrne.

For your replys. I'm shooting the canon 400D and haven't seen the option to turn off the default 1/200 in AV this might be something offered in the higher in SLR I will look again just to be sure.

thanks Don.

No, it's definitely offered Don. Keep looking.

Cheers

James

on my 20D, it's Custom function 3, choice between automatic (0) and 1/250 (1). according to a pdf 400D manual I could find it was the same (but then 1/200), it's on page 104.

Your right cerianthus it was listed under custom functions thanks.