Is it time to dump manual flash?

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@giffenk What camera setting would change that it would know it was shooting manual strobe power vs ttl, is forced flash not still set?


Jumping in here and speaking as an Olympus shooter with S&S YS-01 strobe: I set the strobe on the camera to 1/64 power and the YS-01 set to non-TTL mode then dial up/down the strobes power setting. I always take my first shot into a mirror to make sure the on-camera flash is popped up and my strobe is set correctly (pre-flash or no pre-flash). Camera set to Manual, f/8 at 1/125 and adjust the strobe power by trial, error, experience. Note that it is easy to change to TTL mode by changing the YS-01 to TTL and setting camera flash to forced with camera still in Manual, f/8, 1/125.

I forgot to mention that I am using an Oly Pen E-PL1 camera.
 
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@gstrek Ohhh, so it sounds like the preferred method of shooting strobes manual is to switch from forced flash on the camera into (looking at the tg-4 manual) the SLV mode for the flash, assuming in SLV the flash will always fire based on the ec adjustment.

That would explain a difference in delay between ttl and manual with a fo, thanks!
 
@giffenk What camera setting would change that it would know it was shooting manual strobe power vs ttl, is forced flash not still set?
None. You are correct in that when using an optical slave via a fibre optic cable (or no cable - we did that in the old days) the camera has no knowledge of what mode you have set your strobe(s) to. The camera actually does not even know that your strobe(s) exist.

Hence my (way too cryptic!) response that any "TTL delay" is solely caused by the camera.

When you put your camera in TTL mode it will force a (or several) preflash before the main flash. This preflash sequence takes extra time before the picture is taken.

This preflash delay is annoying as it leads to missed fish - similar to the "shutter lag" problem with many P&S cameras around 10 years ago.
 
I just sold a pair of Inon D2000s and replaced them with a pair of Sea&Sea YS-03's. Now, I have a much smaller package, but no option except TTL. I guess I'll see if I like or regret my decision after my next trip.
I started my scuba photo life using a full auto system: Sea & Sea DX1G and a pair of matching S&S YS110 strobes linked by fibre cable. Using everything on "auto" and "ttl" (photo for dummies) the rig worked perfectly in about 90% of situations. It consistently failed in about 10% of situations.

One of the failure modes was shallow (15 feet) sand bottoms on a bright day. It always super over exposed and gave me pink sand. The other consistent failure mode was night macro: i either got black pics or white pics. It took multiple dive trips to finally figure out the behaviour of the system. At first it seemed to be inconsistent random failures but after a few trips it turned out to be very consistent.

I eventually went manual - with wired sync cables. (there were lots of rumors that the built in optical slave trigger circuit on the YS110 was not very good...)

Back to the OPs original question: Should I dump TTL?
YES! - if your camera / strobe combo is not capable of taking the pics you want. But it will take time and many brain cells to answer the question.
 
... Using everything on "auto" and "ttl" (photo for dummies) ...

Interesting that you would infer that divers/photographers who do things differently than you currently do are "dummies".
 
Interesting that you would infer that divers/photographers who do things differently than you currently do are "dummies".
I meant "dummies" as in "no decisions required" as opposed to "not capable of making decisions".

This contrasts with "no decisions allowed". I have a tiny fully automatic canon that i jam in my bcd pocket. It does not allow making any decisions since it only has fully auto modes. My divebuddy loves this one for taking happy snaps of fish for id purposes. She points the camera and presses the button. No decisions required.

I was lucky with my first rig in that it supported fully auto and fully manual. I started at fully auto, discovered that i was unhappy with some of the decisions it was making and then graduated to making all of my own decisions in fully manual mode.
 
With respect to TTL pre-flash timing consider the following scope capture which is derived from a E-M1 mk II with FL-LM3 on camera, triggering a YS-D2. The scope is measuring the output of a phototransistor sensing the output of the YS-D2. You can see three pulses where the first two are the pre-flashes followed by the actual illumination flash. The horizontal axis is 25 mS/division, where main flash occurs a little over 75 mS after the first pre-flash. Note the vertical axis is arbitrary and related the intensity of the light at the phototransistor.

The first pre-flash occurs almost immediately after the shutter is released. The second scope capture shows a signal from the camera to the FL-LM3 where you can see the similarity to the output of the YS-D2. Note the two captures should not be closely compared as they were not captured with identical camera settings, nor at the same time. I only included it for interest.


TEK0000 2.JPG


TEK0009.JPG
 
hi VSC very interesting. Where have I gone wrong? Reading your chart (1st) it looks like the total time is closer to 50ms, where are you measuring from and to? I am assuming the firing starts at 'ready' point. Are you measuring to final light output at the point of the final arrow?

Anyway, 0.075 of a sec is a lot less than SMoore's article suggested 0.16 or 0.28.

So it must be the automatic camera settings that are causing lost shots of fast moving fish etc. Does this suggest using S setting at say >1/100 to ensure the speed is always capable of freezing most action?
 
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