Synchronising pop-up and external flash

[Sam-D]

Has anyone had any success with simultaneous use of an onboard pop-up flash and an external radio triggered flash?

The kit that I am playing with is a Canon 40D and its onboard flash, a Cactus V4 transmitter connected via a PC lead to the 40D’s PC socket and a Canon 430EX plugged into a V4 receiver.

My aim is to use the 430 as the key and the pop-up as fill. I have tried a combination of settings to try and overcome the problems of things like pre-flash, but so far no luck. So, can any of you ‘flash’ gurus end my frustration with a natty answer as to how I can get the pop-up and 430 to sync.

Thank you.
Sam-D

 

[classcams]

As the pop up is pointing to where the lens points, I can`t see it as a fill in.

 

[planetf1]

The answer for your first sentance is yes, easy. However this was with a Nikon D90 + SB600 which have wireless support out of the box (very useful). Can choose which flash is used, or both & change power of each whilst still controlled by cameras automatic metering.

Sorry I can't help with your canon question

Just posting this for the benefit of others -- it's a feature worth thinking about when looking at cameras.

 

[who?]

When you say that you've tried various settings, what shutter speeds were you using? I would check that you were not too fast. I would expect that there would be a slight delay in the remote firing, so I would start at a shutter speed that I know works with the remote - say 1/200?

I cant see that they have to fire at exactly the same time, just that they booth need to fire in the time that the shutter is open. What's the sync speed on a 40D? I would use a speed slower than that to start with and if you are still missing both then slow down until I got both. Then decide if I was happy with the resulting options and how that leaves you with the apertures you want.

 

[fletch5]

hi sam-d, not sure what problems your having. ie preflash... if your using radio triggers, it wont affect the 430

the only problem i can think of is if the builtin flash wont fire while the sync port is in use, in which case an optical slave would be the way to go.

unless it is a power problem with the built in adjusting when you dont want it to. i think one of the menus in cam lets you set the power of the flash in that instance

 

[david1701]

As the pop up is pointing to where the lens points, I can`t see it as a fill in.

erm, on axis fill

the pop up won't fire with a plug in the sync port (as pointed out above) so an optical slave will be the kittykat (also as mentioned above)

the problem will be I don't think the pop up has a manual mode though this will be worth checking

if all that works fine it will also change relative power in manual as you move the camera though with fill this is unlikely to be a major issue

 

[Sam-D]

Has anyone had any success with simultaneous use of an onboard pop-up flash and an external radio triggered flash?

The kit that I am playing with is a Canon 40D and its onboard flash, a Cactus V4 transmitter connected via a PC lead to the 40D’s PC socket and a Canon 430EX plugged into a V4 receiver.

My aim is to use the 430 as the key and the pop-up as fill. I have tried a combination of settings to try and overcome the problems of things like pre-flash, but so far no luck. So, can any of you ‘flash’ gurus end my frustration with a natty answer as to how I can get the pop-up and 430 to sync.

Thank you.
Sam-D

First of all - Many thanks to those who replied to my original post.

After several evenings of messing about, I have finally found a way of firing a 40D’s pop-up flash in sync with a 430EX mounted on a Cactus V4.

So, if anyone else fancies a go then this is how yer do it....

Set camera on manual

Activate pop-up flash

Plug radio transmitter into camera pc socket

Mount flashgun on receiver

Switch on and set slave switch to ‘off ‘

Push mode button to select ‘M’ and then set flash power

Push zoom button and select

Meter/guess your flashgun exposure and set camera accordingly

OK – You’re now ready to start shooting...

Line up the shot and push the * button (Flash Exposure Lock) to pre flash pop-up and flashgun, then recheck your composition a take the shot.

JOB DONE!

If the viewfinder information display ‘times out’ before you take the shot then the Flash Exposure Lock will need to be reset. To avoid this happening keep your finger on the * button and the viewfinder info display will stay active, so you can happily wait to ‘capture the moment’. Keeping the * button pressed also allowing you to continue taking further shots without having to go through the pre flash.

The pop-up flash exposure compensation is still operational, so by cranking it down, say – 2 stops, it’s acting as a fill and also provides those handy catch-lights.

If you are shooting in dark locations pre-flash may fire to assist autofocus. If this is annoying or distracting then go into the menu and find C.Fn111-5 (halfway down orange coloured menu) and set to disable.

If the 430’s power save is a problem, (kicks in after 90 seconds of flash inactivity) there is a menu option to disable it.

During my experimentation, I also discovered a handy way of using a remote radioed flash in very dark locations where you need some sort of focus assist, but you don’t want pre-flash. However, this technique does not allow you to use the pop-up simultaneously....

What you do is switch the flashgun to slave, hold the mode button down for 2 or 3 seconds until the ‘M’ flashes and now set the flash strength and zoom as usual. You will see that the AF assist beam flashes continuously. This not only gives you your focus aid, but also makes it a doddle lining up your flash onto the subject and it’s really quite indispensable if you are working with an assistant who is mobile with the flashgun, stalking your subjects and trying to maintain the flash aim in busy and crowded situations.

Happy flashing.
Sam-D