Do you TTL or Manually Set your Strobes?

[Larry C]

I always enjoy your technical insight, Ron. Knowing nothing about how the camera does what it does often makes it difficult to make accurate changes. Thanks for your usual enlightenment.

 

[mddolson]

I have an Olymous c-750, Ikelite housing and Nikonos sb-105 strobe.
This arrangement only allows for manual operation, since the preflash triggers the strobe otherwise. Covering the preflash triffer and quelsh contacts on the hot shoe allows manual operation, with an otherwise non-digital strobe.

I use the histogram meter function to adjust the exposure.

Mike D

 

[louisianadiver]

Like many others, I use TTL for macro almost all of the time. I go manual for wide angle almost all of the time. I've come up with an ISO speed, f-stop, and strobe power for a good exposure from a distance of 3 feet, and I either shoot from 3 feet or vary from there. I set my shutter speed to get the background color I want. I've found that "auto" modes create a background/ambient exposure that is too light for my taste, not to mention that TTL can burn out small subjects. -Clay

 

[Larry C]

not to mention that TTL can burn out small subjects. -Clay

Especially if they are on sand or other white background, or are highly reflective. I've blown out so many Lemon Dorids I can't count them all.

 

[Wolverine]

I use manual all the time, but that is probably because my current setup (and my future one I suspect) would not have TTL. Personally, because I bracket anyway, the manual mode seems to work. For WA shots, I think manual is the only way to go. As for macro shots, I bracket at least 3 shots with different apertures to get a proper exposure.

 

[f3nikon]

I've found that "auto" modes create a background/ambient exposure that is too light for my taste, not to mention that TTL can burn out small subjects. -Clay

That’s because small subjects (open backgrounds) do not reflect enough light back to the TTL sensor on the camera to tell the camera to tell the strobe to turn off. Not a problem in manual light control, we just open or close the aperture to control the exposure, vary consistent results every time. You can “trick” the camera for a darker background/ambient in “auto” mode by adjusting the exposure compensation dial to a darker setting.

 

[f3nikon]

I use manual all the time, but that is probably because my current setup (and my future one I suspect) would not have TTL. Personally, because I bracket anyway, the manual mode seems to work. For WA shots, I think manual is the only way to go. As for macro shots, I bracket at least 3 shots with different apertures to get a proper exposure.

Thats one way to control ones destiny, total light control and not relying on the subject being too light or too small or too far or too close. TTL was a bigger help when using film cameras, where there was no instant feedback via the LCD screen, as with digital cameras. TTL is not the magic bullet.

 

[f3nikon]

Especially if they are on sand or other white background, or are highly reflective. I've blown out so many Lemon Dorids I can't count them all.

Just curious if you "blown out so many Lemon Dorids" why didnt you switch to manual mode to correct the problem? Are you sure your TTL system is working? Because if your TTL system is working and you are using it within its range, light or high reflective subjects should tell the sensor to tell the camera to tell the strobe to turn off much sooner...yeilding Under Exposed images.

To check if your TTL system is working properly, set your camera and strobe to "TTL" mode, now manually set the shutter speed to about 1/60 or 1/125 of a second. Starting from the lowest aperture of maybe f2.8 take a flash photo of a flat subject about 2.5 feet away, at each of the aperture settings F2.8, F4.0, F5.6 etc.

In a working TTL system, each one of those images should have the exact same exposure as the next, this is because as the aperture opening gets smaller the TTL sensor is getting less light and is telling the camera to tell the strobe to pump out more light to correct for the lack of light! So much for light control, just leave your fate with TTL and let Photoshop take care of the rest.

 

[Larry C]

I think a bigger issue is strobe aim and distance from subject. Most of my best macro subjects are in holes, behind kelp or on rocks among other rocks. Positioning the strobes and getting the camera close enough to the subject without either putting the strobe behind a rock or right on top of the subject can be a challenge, but that's another thread entirely. With the sea lemons, I'll get a shadow on one end and a small blown out patch with the rest of the picture well lit.

 

[RonFrank]

I always enjoy your technical insight, Ron. Knowing nothing about how the camera does what it does often makes it difficult to make accurate changes. Thanks for your usual enlightenment.

Thanks, Larry! :blush:

Glad to hear someone reads this dribble! :lol: