I'm using a TTL studio light and would like to trigger one of my manual studio flashes to use as a hair light. The problem is, the manual light is set to slave mode and is firing on one of the TTL pre-flashes (in other words, too early).

Is there anything I can do to sort this without buying a specialist receiver?

  • \$\begingroup\$ Use a cable for the hair light instead. \$\endgroup\$ Commented Dec 28, 2016 at 8:28

2 Answers 2


If your manual flash has a second (or third) slave mode, often called "S2" (or "S3"), that will ignore the first pre-flash from your TTL flash you can set it to "S2" (or "S3") and see if that solves your problem. A few manual flashes will have an adjustable delay that can be used to do the same thing. If your manual flash has neither of these capabilities then your only other option without buying anything else is to use the TTL flash in manual mode so that it does not emit a pre-flash.

In general manual flash is preferred over TTL flash for studio work because it can be more consistently applied from shot to shot.

Your subject may be wearing dark clothing and have a very light complexion. The same subject may then change into a lighter outfit. If you're using TTL flash then the TTL system is going to alter the output to make the lighter outfit the same brightness as the darker one which will cause the subjects skin tones to be exposed darker as well. Or you may have two or more models with lighter or darker skin tones and clothing. The way you arrange them in the frame will change the way the TTL system calculates exposure and your results will not look consistent.

The preflash from a TTL system, particularly if multiple groups are used, could also close your subjects pupils down which is often not desirable.

TTL flash is really intended for situations where the photographer doesn't have as much control over every aspect of the lighting, of the subjects, and of the situation. A party, for instance, where people are moving around in dim light and where the shooting distances are changing rapidly from shot-to-shot.

  • 1
    \$\begingroup\$ You have answered the question in your first paragraph but all of the other information has nothing to do with the original question. The part about closing the subject's pupils is also false. Could you either remove the unnecessary information or provide a reference for the pupils point and on balance, the reasons why you might use TTL studio light, e.g. fast moving subjects, outdoor use, HSS (low aperture or high shutter use). \$\endgroup\$
    – connersz
    Commented Dec 16, 2016 at 22:50
  • \$\begingroup\$ There's around 3/16 sec. latency before the pupil even begins to constrict, and that's much longer than the (usually unnoticeable) delay between preflash and flash unless you're using a long exposure and second curtain sync. Other than the 2nd curtain sync case, it seems unlikely that preflash will affect anybody's pupils. \$\endgroup\$
    – Caleb
    Commented May 16, 2017 at 22:51
  • \$\begingroup\$ @Caleb Maybe with a single flash group. But have you ever seen the pre-flashes from the Canon E-TTL system when multiple groups are being used? The various metering flashes and communication pulses to each group can take well over 3/16 second in total. Look at the diagram with this answer \$\endgroup\$
    – Michael C
    Commented May 16, 2017 at 23:02

Is there anything I can do to sort this without buying a specialist receiver?

Depends on your definition of "specialist". :) If you mean any radio receiver, then you're probably out of luck. If you mean a TTL radio trigger, then you might be able to.

It's unlikely that your manual studio strobe has a way of ignoring the pre-flash with its optical slave, particularly if it's older or lower-cost. TTL in studio strobes is pretty damn new. And unless you're willing to take it out of TTL, you're going to have that metering preflash.

But, if you're using Phottix Odin IIs with your Indra 360 as your TTL studio strobe [as you stated in a previous question], then you could probably just hook a manual-only Strato II receiver up to the manual studio strobe and you could trip it with your Odin II transmitter.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.