Hi All, I just came back from a trip to the Philippines (amazing btw) and I was upset that my setup E-PL3 + 2 x YS-01 was unable to shoot faster than 5 sec between shots.
the main reason is that I'm using TTL, so the internal flash of the camera needs to recharge fully every time, so after thinking on many solutions, I manage to get a good working solution to shoot as fast as 1 sec between shots without loosing the TTL, on the way, I managed to save battery life of the camera, and some will say even reduce the chance of fogging since the internal flash is not heating the housing.
So, how did I do it? simply, we all know that we don't really need the internal flash, just the external strobes, we need the internal flash to signal the TTL, that's all, so I just lowered the flash to 1/10 of its power.
I'll give a small explanation to those who don't know how the flash works, if you do want and you just want to see the MOD jump ahead.
Ok, so I'll try to simplify all the technical details so some of the things here will be not 100% correct, but just close enough.
We have the flash bulb, to activate it we need power, the main problem is that to get to such a strong intensity we need strong power, and we only have a small battery in the camera, so we will use a simple device called capacitor, capacitors are devices that holds energy, so to "fill up" the capacitor with energy, takes time, the bigger the capacitor the longer the time it takes to fill it with energy, so all I had to do is replace the big capacitor with a small one, that's all. now my flash is very week (we had a 102uF capacitor, I used 10uF so 1/10 the strength [yeah yeah I know it is not linear but still you get the idea]).
I'm using the E-PL3 that uses the same flash system as the OMD and other PEN units, but I believe it can be done to any flash.
Full Flash before the mod:
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Full Flash after the mod:
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our flash is FL-LM1 or the FL-LM2. if you disconnect it from the camera, you will see there are two small bolts, when you open them up, you can see the whole flash system, there are two capacitors, one is the triggering (small one, can get to 4000v) and the second one, the one that we are interested in is the big one, 330v 102uf.
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BEFORE YOU TOUCH IT! the capacitor is charged! that means it has 330v in it, be careful, you should discharge it first (how? if you don't know better not to do it ).
so you can see all you need to do is take a new capacitor, solder it to the same wires with the same connectivity, and you are done, I've checked few capacitors before I ended up with this one - 350V 10uF, (No need to go higher - 10uF works 100% I get green light on my strobes every shot) I've tried also 1uF, it was too weak, you could see the flash firing, but couldn't get TTL to work 100%, so I guess you can find a better value between 10-1 but I'm happy with the 10uF.
Old capacitor Vs New capacitor (smaller one is the new one)
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So now I bought a new flash on ebay, and I have one for "land" use (not modified) and one for underwater use. Total price of the mod, 0.5$ capacitor + 35$ used FL-LM1 total 35.5$!
I can only give you one more tip, if you buy a new flash, buy in a different color (if you have silver camera, buy black and vice versa), so you could differentiate between them .