Hey guys,

I've been wanting to switch from using onboard flash on my 7D to a flash trigger for a while. Not only can I never use burst mode, but sometimes when I take several photos in quick succession, the built in flash will take 5-10 seconds to recharge which leaves me dead in the water right when I want to be taking photos.

The obvious solution would be to purchase a hot shoe flash trigger. However, there are two issues:

• I don't think Aquatica made a flash trigger for this camera/housing combo

• I probably wouldn't pay $500 for one even if they did

I think I have two options, the first being to find an off the shelf product that will accomplish what I need, kind of like this: https://www.amazon.com/Godox-Flash-iM30-Mini-Full-Power/dp/B0DGKGQ4FH

The issue with this is that the only products I can find are actually true flashes, not LEDs. Their recycle times are probably the same or worse than my camera. I can't believe I'm saying this, but I wish I could buy a mislabeled camera flash that is actually just an LED strobe. Of course, it'd still need to somehow fit inside the housing, but I imagine I could take it apart and make it work. This would be the simplest option. I could probably buy another flash trigger and take it apart to fit my setup, but again, they cost hundreds of dollars.

The second would be to try and build my own. I only use manual, never TTL, so I don't need complex electronics. I just need two LEDs to light up when the hot shoe fires, ideally with decent battery life. I am no electrical engineer, but I imagine this is relatively easy to accomplish. I'd then just need to make a small plastic or aluminum housing for the board/battery and either position the LEDs right under the bulkheads, or have the LED bulbs on wires that attach directly to the bulkheads. Please correct me if I'm underestimating the complexity of flash triggers.

Has anyone attempted to make a flash trigger? Open to all suggestions. I'm sure I haven't thought of all the ways to get around this problem.

I use the little accesory flash that comes with my OM-1 and I set it at 1/64 power which seems to be more than adequate to use. Do you have the option to set flash power in the camera menus? Looks like it can be set to manual and as low as 1/128 power which should recycle very quickly.

Also if you are looking at manual triggers, these generally only have the center contact and the shoe to complete the circuit, so and any model trigger will work on your hotshoe, the difference being only achieving alignment of the LEDs with the fibre optic ports. There are a few ready built manual triggers sold out there which should work with your 7D, you would be looking for a model with the LEDs on wires to mount in your fibre optic ports. Still pricey at around the $200-250 mark.

The circuit itself is simple in principle but finding the right LEDs might be a challenge. This post on th old wetpixel discusses :

https://wetpixel.com/forums/index.php?/topic/62410-the-ultimate-diy-led-trigger-olympus/&tab=comments#comment-429772

You may not be able to read it unless you sign in though. It links to this post:

https://www.instructables.com/LED-Strobe-Trigger-for-Olympus-OM-D-E-M1-Mark-II/

You would have to adapt it to using circuit board to build and source a hotshoe and the right parts of course. The biggest issue is finding LEDs which will work and not burn out. You need quite high power LEDs to reliably trigger strobes.

Thanks Chris! Didn't see this until now. My camera flash is already set to the lowest setting and while the recycle time isn't terrible, it will give a prolonged BUSY message and lock the shutter when the flash is used too many times successively. I wonder if maybe a fresh Canon battery would help with that.

I wish I had a Wetpixel account so I could see the post you linked. Thanks for linking the article; it seems to be exactly the guide I was looking for. Good point about the LEDs themselves. This is exactly the type of insight I was looking for to convince me I'm not saving money/time trying to hotwire something myself. I think you're right that the best option for me is to buy a manual flash trigger and position the LEDs correctly in my housing. The Sea&Sea, Fantasea, and TRT options are relatively inexpensive and the LEDs are already on wires.

2 hours ago, sammycheez said:

Thanks Chris! Didn't see this until now. My camera flash is already set to the lowest setting and while the recycle time isn't terrible, it will give a prolonged BUSY message and lock the shutter when the flash is used too many times successively. I wonder if maybe a fresh Canon battery would help with that.

I wish I had a Wetpixel account so I could see the post you linked. Thanks for linking the article; it seems to be exactly the guide I was looking for. Good point about the LEDs themselves. This is exactly the type of insight I was looking for to convince me I'm not saving money/time trying to hotwire something myself. I think you're right that the best option for me is to buy a manual flash trigger and position the LEDs correctly in my housing. The Sea&Sea, Fantasea, and TRT options are relatively inexpensive and the LEDs are already on wires.

I think unless you have experience in electronics, probably best to buy something. Any trigger that only has the large centre contact should work for you. You didn't say which flash you wanted to trigger, manual triggering is usually problem free, but if you are triggering a known difficult strobe like a YS-D2 you would want to be sure the trigger put out enough light. An additional possibility would be to use electrical sync cords if that is an option with your strobes, though you would then be maintaining the additional o-rings and dealing with the usual sync cord issues.

I'm currently using Inon Z240/Z330s but am working on upgrading to HF-1s. I've used electronic sync cords before and never had an issue, but I definitely prefer fiber optic. It'd be cheaper for me to just get a flash trigger than to switch over as well.