Does "TTL" mean fire away?

Hi!

i need to know what "TTL" means? Does it mean that when i shoot in Manual mode, no matter what apeture i set, the strobe would just fire the correct intensity of light? thus meaning that i would never get a under exposed picture?

thanks

Most say TTL means "through the lens" but technically it mean Thyristor Thyristor Load" thanks to an explanation by Marty Snyderman. Your analogy is correct. If you have a TTL camera and a strobe that talks to your camera that is also TTL, and you have a TTL sync cord, you can shoot on manual and set the strobe on TTL. You, in theory, will get good exposures. But don't let that fool you. You can get way off exposures with TTL depending on certain instances. High reflectivity, hi absorption, ambient light trickery, strobe position, etc. Also, if the subject is too close and the strobe cannot deliver low enough light to expose the subject properly, you would end up over overexposed. Conversely, if you have the strobes too far away from the subject, the strobes can give you a full dump and not deliver enough light, thus you are underexposed. You need to either change shutter or aperature of adjust your strobe to subject distance accordingly.

So, technically your definition is correct with some exceptions. In Wide angle getting good ttl pictures is an absolute art. It's better to shoot in full manual on Wide angle because the ambient light, primarily, fools the TTL into shutting off or staying on too long, thus over or under exposing.

Joe

I love to take "seascapes" with wide-angle and fisheye lenses. I have never got good results from TTL strobes, and have never worried that TTL function has been difficult or impossible with most housed DSLRs and mainstream underwater strobes.

I bracket strobe exposure from fixed positions with Inon strobes that have multiple power settings, but are small enough that I can handle two on long arms without awkwardness. Sometimes the lower power settings, that can't be achieved in TTL when there is open water in the frame, give the most dramatic images.

My friends tell me that TTL works wonderfully in macro photography, but as far as I can see it's difficult to get a really new, exciting macro image because so many have been taken and published in the past.

TTL used to work quite well on the Nikonos system, where you could fool the sensor by changing the set film speed; again, underexposing the TTL (by over-estimating the film speed) often produced the most exciting images with a 15mm lens.

Can someone take up this discussion by adding their experience with TTL in macro photography, to balance my thoughts?

Tim

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