simonknee

Some more pics of the adapter in situ... First the 50mm macro snout! You can see the control knob is nicely placed. The adapter is the correct length to allow full extension (close focus) of this lens. The gearing works correctly to allow manual focus but with the 50mm only allows fine adjustment since the oly gear has end stops. Fine for photos since AF can do most of the work but I shall need to come up with a custom gear for video. (n.b. it takes several full rotations to focus the 50mm infinity to close - and it is velocity sensitive too but you don't get much speed up on the knob) On with the dome - it actually goes on a few more mm than this pic shows and closes up the gap you see here. But then you have to re-adjust the petals and I couldn't be bothered for this little shoot From above The lovely 8mm sitting where it should Now the 11-22mm with "customised" (draught excluder) gear from a 7-14mm. A bit tricky to assemble as the knob has to stay in it's pulled out position. But it all works as it shold which means the even larger 7-14mm would fit in this rig too. With dome and per-02 extender. I do not think this is at the nodal point at all and need to get a per-01 instead. However there is no vignetting from the dome so it is worth testing in the water. And finally the lovely leak light showing I am leak free Simon

Look what arrived for me in the post today... Thanks Alex, I'll let you know how it goes (not in the water for a couple of months mind you) Also got the replacement vacuum indicator bits - doesn't look to hard to swap at all. Includes two spare LED in case you break the existing one getting it out which is a thoughtful touch. Simon

Testing of resistance mod: (my erratic exposure above F16 was down to the erratic closing of the aperture blades on my 50f2, I am now testing with my 11-22 @22mm as it is a happy snapper at all apertures) So in an effort to increase the resistance of the tube (and use less power) I added some resistance. I soldered in a 1ohm 5watt wirewound directly to the anode of the tube (pic later). The flash still worked but this made little difference to recharge times. There is plenty of power going through here which soon destroyed a 10ohm 1W carbon resistor (nice internal explosions). So digging about in the component drawers I settled on a 6R8 (that's 6.8ohms) 22W wire wound resistor. I will try and do the maths on what is a suitable wattage later - suffice to say please be careful if you try this, no fires please. When testing in the housing with a pair of Sea&Sea this shaved 1/3 off the recharge time compared to an original FL-LM2. However reviewing the images from my resistive flash showed that as the aperture got smaller the exposure got brighter (tried another lens to confirm) AT F10 exposure was the matched, at F22 it was approximately 1 stop brighter using the resistive flash. I guess the mod upsets the pre-flash a bit and causes the EM-1 to think it needs more light. So I stopped down the flash (on the EM-1) to match exposure and of course recharge time was even quicker. The camera was able to keep up with the recharge of the S&S (YS110a & DS-01) on a dining room table test at least. This is a double-edged sword for me since though it appears predictable it means there is more to remember to adjust which isn't really the ethos of TTL. Though adjusting flash exposure at the camera is much easier than in manual on each of the strobes. Onwards and sideways Simon EDIT: As to this mod upsetting the pre-flash I did notice that the light produced by the flash dropped away more dramatically than the original as you moved down the full, 1/2, 1/4, 1/8 ... flash settings (tested on it's own out of housing). The resistor mod does appear to adversely affect shorter flash times (perhaps it causes a tiny start delay?). This does mean that there may be issues with short flash durations even in the housing - only UW testing will tell if these shorter durations are even needed.

Yes they do Karen, however the base of the ball also has the screw threads that the upper support bracket (silver metal in the pictures) attach to. With out this the handles are not as stable - it's not that bad though about 5mm flex if you push, I would be happy to use. So may want to ask Nauticam if there is an alternative top piece for the handles. The screw thread is large M8 I think but don't quote me on that. Simon

Screws are all underneath sticky tape. Flip the flash up and remove the bit of tape. You will find the ones you need to take the top cover off. Sent from my Nexus 4 using Tapatalk

OK I was able to do some testing even with the >F16 fault. These are the original tube (large) and a tube from a Nokia phone. EM-1 in Nauticam NA-EM1 housing optically firing a Sea&Sea YS-01 Setting the camera to F14 and shooting the same test scene YS-01 lights green to show TTL. Pictures expose the same with either bulb. But the nokia tube is draining the battery MORE! It takes three blinks of the flash icon on the LCD for the original tube. Yet four blinks for the smaller Nokia. In both cases the YS-01 recharges in under a second but it is taking 3-4 seconds for the FL-LM2. Ho hum - to be fair I have no specs on the nokia tube other than it's size. Worth a punt mind. Simon

So a smaller tube arrived and I put it in. I think it was faster. However testing of recharge time was curtailed by a bigger issue. With my 50mmf2 attached as soon as I go smaller than F16 on my EM-1 the FL-LM2 gets unreliable and more often than not completely over exposes. Perhaps I have damaged my FL-LM2 so I need to buy another before I can reach any conclusions... EDIT: I put the original tube back in and the problem is without any UW strobe or housing. Plus I did a full reset in case I had mucked up a setting. The flash/camera might have had this problem from day one so glad I've been fiddling and spotted this since it would have made shooting underwater very haphazard.

I opened up the rest of the flash at the weekend and I suspect that the complex little circuit precludes reverse engineering. It is a double sided pcb with a bunch of surface mount stuff. I could not find one of the two 10-pin SMD packages when I searched online. Personally I think modding a circuit that already does the job as Olympus intended is the best route. I am going down the other track and have ordered a spare xenon for a mobile phone camera (Nokia 6022) to see if it is lower power. Simon

What are your thoughts on how to implement LED trigger/quench since the voltages floating around are not exactly suitable to say the least! Simon

Possibly Bart, though I am aware that adding resistance to any part of a working circuit without a proper understanding of what the designers intended might just render it useless. I too wonder about led, from a quick Google hunt it seems that there is success as a trigger but not as a ttl. Retro fitting a lower output xenon is another option. Not sure how to source such a thing mind. Most suppliers of xenon tubes want to advertise how bright theirs are! Sent from my Nexus 4 using Tapatalk

Hi, Just picked up on this and it is a very interesting idea. I have a hunch that when you use a flash-specific capacitor you may no longer get the results we desire. I think that the reason this is working is that the standard-grade capacitors you are using have a slower maximum discharge speed due to higher internal resistance. This is causing reduced flash intensity and so allowing the same duration of flash for less power as the standard size capacitor. With a proper high-speed flash capacitor you will not be able to achieve this any more. Lets see if your next test bears this out or not. My concern is that if this is the case and you need to use standard-grade capacitors to achieve this effect then you run the risk of overheating the capacitors as they are really designed for use in power supply smoothing applications not high-speed discharge. However this makes me wonder if there is an alternative mod we could do using the standard capacitor but increasing the series resistance slightly. Have you tried this on your test bed? EDIT - though this would limit the charging speed too so not a great idea Simon

Wow Phil! Can't wait to get this stuff wet. What is a SAGA +15 C/U lens? Simon

Thanks Phil, I cannot find an EM-5 settings link - not searching with the correct words perhaps - and that EM-5 thread is pretty big now! Didn't know about the wedge - that's a great idea from Nauticam - but now you raise the spectre that I'll forget to fit the flash ;-) If you get a chance would you please see how deep you can set an custom WB on a white card. I know you don't use it but I used to love shooting like this with a Canon compact back in the day. Also have you tried the UW WB setting? Any thoughts on what it does? Simon PS I know that much of this is redundant if you shoot RAW and do PP but I find nothing satisfies like getting a great jpeg shot in camera (I still capture RAW+JPEG anyway).

Since I have no water to play in I thought I might as well trawl the menus of the EM-1 looking for UW specific/useful settings and options. WB Underwater preset - anybody know what this actually does as the manual is very shy at explaining this mode. Is it a modified AutoWB or is it a fixed temp (if so Oly don't specifiy a colour temp in the manual's chart) One Touch WB - needs some thought as to which button is best for this since you have to be able to hold it whilst triggering the shutter and your other hand is probably holding a white card. How blue (or if you prefer, red) will it go before you get a "WB NG Retry" message is to be seen. Settings menu items of note (I'll update this as I find more): Menu A AEL/AFL (as Phil uses) choose mode 3 for S-AF (and C-AF or MF) to separate focusing onto the rear lever. AF Illuminat. - OFF or there may be a nice red internal glow! Face Priority - OFF Menu B Buttons One Touch WB - useful for available light photography Underwater Mode - handy if you did not raise the flash before loading the EM-1 into the housing since it forces it to fire in the down position. However it also presets the WB, ISO Exposure Compensation & Flash compensation and worse it locks the setting of Aperture & Shutter & Picture Mode. This makes it pretty inflexible but might save a dive since I see no other way to get a down position flash to fire. Menu D Live View Boost - ON to remove the effects of exposure compensation. Very useful for full manual shooting. Menu F Exposure + Flash - ON makes the exposure compensation dial vary flash intensity at same time. Menu G WB Auto Keep Warm Colour - OFF though it might be worth experimenting Flash+WB - OFF so that the WB you set, such as Cloudy, is not overridden in flash mode Menu J EVF Auto Switch - OFF otherwise the proximity of the case means the EVF is always active. Menu K Touch Screen Settings - OFF might as well be off. Anybody have any more? Did anybody do a similar exercise for the EM-5 (a camera I have not owned)? MySets a bit of a pain to setup but worth it. I am currently making Myset 3 a flash setup and Myset 4 an available light one (and as I write this I realise I should do a separate wide angle and a macro MySet too). MySet 3 Flash: Buttons: Fn1 - not sure yet - Preview Fn2 - Focus Home Rec - Record Front - Myset 4 (then can easily drop to available light mode and back) Arrows - Focus Point Select (though could use these for direct access to flash mode) Baseline Values (note): S-AF F8.0 (for macro shooting in A priority) ISO 200 WB Cloudy Manual Flash adjusted to 1/64 (for use when setting flashed manually) but flash mode then set to TTL note: before I store the MySet I am also pre-setting some default values which makes it easier to get back to a baseline after fiddling. Myset 4 Available Light: Buttons: Fn1 - One Touch WB - seems easiest to hold in conjunction with shutter release Fn2 - Focus Home Rec - Record Front - not sure Arrows - Focus Point Select Baseline Values: S-AF F3.5 (I tend to shoot in A priority mode) ISO Auto (max ISO1600) WB Custom 1 (note) Flash OFF note: If the custom WB works well underwater there are 4 memories available which would allow settings for, say, 4/8/12/16 meters to be made on the descent. Then these could be recalled as you rise back up so no scaring fish with the white card! The reason I like all this is that I have often plopped into the ocean to find I have forgotten to optimise one or more of the settings and then spend the descent fiddling with the camera when I should be paying attention to other things - surroundings, conditions, perhaps even my buddy. Also as the dive profile brings you shallower I like to try available light shooting alongside flash but there usually too many things to alter and you forget something or miss the opportunity. With the EM-1 these issues could be a thing of the past! Simon EDITTED on 9-1-14 with myset info

I think you should go for settings menu "A" AF/MF, then choose (right arrow) AEL/AFL setting, then choose (right arrow) S-AF, finally set this to "mode 3" and press OK. (Normally you would have this set to mode 1) Simon