# Canon flash question



## JanS (Apr 14, 2004)

I bought the Canon 420EX speedlite for my Powershot G2 (which is the flash they recommend for that camera), but I can't seem to get it to work correctly.

When it's mounted on the camera it washes the photos out terribly (read almost pure white) even though I have the settings where they are supposed to be according to the book.
When I use it as a slave flash it works great.

I've tried cleaning the contacts, but that didn't help either.

I really hate to have this semi-expensive piece of equipment sitting here doing nothing....

Any ideas?
Thanks!


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## BigFoot (Jan 3, 2005)

when photographing a aquarium it is best to have no flash or a delayed flash imo


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## JanS (Apr 14, 2004)

Thanks for the reply Bigfoot.

Sometimes it's nice to have a bounce flash, or whatever in certain situations.

Anyone have any ideas why it is doing what it is? 

PS, obviously this is a "bump".... ;-)


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## Aaron (Feb 12, 2004)

I'm no expert, but I will give this one a shot (since I too have a 420ex and I kinda sorta got it figured out) First things first, what are you shooting? your aquarium? Are you talking about glare off the glass? If this is the case, you will need to change the angle of light coming from the flash in a way it does not reflect straight back at the camera. This could be done by shooting the tank at an angle, bouncing the flash off a card, or putting the flash on an arm or bracket, coupled with an off shoe flash cord to the side or above the camera. When using my flash, I will always shoot with an arm because it allows me to square up right in front of the glass, giving me a distortion free shot. (shooting tanks at an angle will screw with the focus and give off all sorts of distortion)
I could go on, but before I do, can you give some background on how you are using the flash? ie shooting modes, flash settings, aperture/ shutterspeed etc.


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## niko (Jan 28, 2004)

Jan,

Under normal circumstances any flash has a maximum as well as minimum working distance. If the camera and the flash are working properly then the camera simply can't find the correct exposure because the light from the flash is too strong.

You have the following options to try to get normal exposed images:

*Move the flash away from the subject.*
I'd say that is your best bet.
You will need a cable to move the flash away and not rely on the "slave" functionality. With the Canon 420EX getting a correct exposure for a macro picture maybe a bit trickier that I'd like to think. The flash doesn't have a setting that fires it at constant power. It will always try to adjust itself by communicating with the camera. Still moving the flash away from the subject will probably result in good pictures.

*Reduce the power of the flash burst.* 
Unfortunatelly from what I see online the Canon 420EX does not have a way to reduce the light. Consult the manual and I'd be happy to hear I was wrong.

*Trick the camera into going off at full power.* 
Basically this is tricking the flash into firing at a constant power - its maximum that is. With such a powerful flash that is a total loss of battery life but unfortunatelly if I understand the info correctly the flash doesn't give you a way to set the power.

There are 2 ways to do trick the flash to fire at maximum power:
--1. Simply block the flash head (head only, nothing else) with a white material (fabric, plastic..). 
The flash will still get instructions from the camera but it will try to provide as much light as possible (meaning maximum power) because the white material will lower the light output. 
--2. Use a neutral density filter on the camera lens.
These filters come in a few densities. They reduce the amount of light that enters the lens. By using such a filter you maybe able to take correctly exposed pictures with the camera and flash very close to the subject. The problem with your flash in particular is that it's very powerful and even the darkest neutral density filter may still be too weak to reduce the flash light to an acceptable level.

Try moving the flash away first  Let us know how it worked.

--Nikolay


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## glenhead (Jan 29, 2005)

Here I go traipsing out on a limb again...

Is there a way to choose your metering "scope"? On my A2E and Elan II, there are three different metering settings - spot, center-weighted, and average. The three settings go progressively wider - if I shoot the tank with center-weighted metering, the lower-flash-level things in the back get averaged in with the higher-level things closer to the flash, and it washes out more frequently. With spot metering, the flash quenches based on what's in the much smaller center spot, and I get a better result on what I'm actually trying to get photographed (though the other things in the frame may be underexposed). I'm watching eBay for an off-camera shoe cord to give that a try. Right now I have an OmniBounce sort-of umbrella thingy that really helps with diffusion, and I think that separating the bounced and diffused flash farther from the camera may help even more.

Don't know if these new high-falutin' digital thingies do the same thing as my archaic film camera, but you young whipper-snappers may be able to figure something out. ;-)


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## gpodio (Feb 4, 2004)

Jan, what settings are you using on your camera when you get these washed out results? In general, most cameras can't correctly meter close shots and particular lighting situations such as our tanks, specially with external flashes. Used as a fill-in or slave flash works well but when it's mounted on the camera itself even my 20D won't meter correctly and greatly overexposures the shot. I find I usually need to manually reduce the flash intensity along with speeding up the shutter speed to get it right. Obviously this requires to use the manual mode of the camera.

Hope that helps
Giancarlo Podio


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## JanS (Apr 14, 2004)

Thanks for all the tips - I can't believe I completely missed that there were new replies..... :-s 

I'll try some of the things you guys mentioned and let you know how it goes.

It's been a while since I've played with it, but I tried nearly every setting and mode I could think of with the same results every time. Even a photo taken across the room of things other than the tanks comes out completely washed out.
I do have the LumiQuest softbox, and that does help a bit, so maybe some of the above suggestions will work (fingers crossed).


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## pescadero (Mar 29, 2005)

Try searching the Canon Talk forum at Digital Photograpy Review. There are a lot of folks there using the same camera and flash.

http://forums.dpreview.com/forums/forum.asp?forum=1010


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