Diffuser Dilemma

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R.Y.K. LEE

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Ray
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Hi everyone,

I am new to using flash in my photography as I normally shoot ambient light. I have got myself a 430ex II to use with my new 7D and was wondering how can I "improve" the quality of light I can get out of it?

I have seen so many different diffusers but can't seem to decide on one. These are the ones I considered.

- Sto-fen type diffuser (3 colours - blue/yellow/white)
- White bounce card with velcro strap (matt side/gloss side)
- Material sock/bulb-like thing :D
- Gary Fong Lightsphere type (4 colour domes - yellow,blue,orange,white)

Also noticed some for pop-up flash too.

Do you guys use diffusers on your flash guns? If yes, then which ones, in your experience, works the best? Thanks in advance.

Ray.
 
With a little bit of effort and learning, good flash technique will transform your pictures :)

It's important to understand how these diffuser things work. Basically they all diffuse the flash which means they redirect it in various directions, or usually all around. The light then bounces back from the surroundings, mainly the ceiling, which then becomes a much greater surface area so the light is a lot softer. In addition, some light will go directly from the flash to the subject.

In this way, if you balance things up properly, you will have most of the light coming down nice and soft from the ceiling, plus a bit of direct fill-in that lifts shadows from under eyes and chins, and puts a sparkle in the eyes. It's a great combination - called bounce/fill - but without reflective surrounding for the light to bounce off, these attachments do virtually nothing. For example if you use a Stofen outdoors, all you are doing is squirting light into nowhere, wasting power, and gaining absolutely nothing. By the same token, they are all highly dependent on the surroundings and TBH they are all much of a muchness. For example, don't believe all the marketing guff that Mr Fong puts out, he is very economical with the truth ;)

I use two flash diffusers - a Stofen because it so easy, cheap and robust. Get a white one. Most of the time, it works very well - except outside.

Which is why I really like the Lumiquest Quik Bounce which is about £40 http://www.lumiquest.com/products/quik-bounce.htm When used outside or where there are no bounce surfaces, you still get a useful amount of softening (because it makes the flash bigger) but it doesn't waste any light blasting away behind you like some others.

Then when you want to do bounce-fill, you have a lot of control with the little trap-doors and you can vary it still further by zooming the flash head. In that way, you can get the right bounce-fill ratio even with quite high ceilings etc. Plus you can flip it vertical or horizontal in, erm, a flash.

Finally, get a CTO gel, which is light orange. When shooting in normal room light, it adjusts the colour of the flash to match the ambient for correct colour. You can even use the cellophane wrapper from a box of Quality Street and get a half decent result ;)

Shoot in E-TTL - it's a doddle and works a treat. Learn how to further adjust the ambient and flash exposures by shooting in Av with +/- compensation on both the camera (which adjusts the ambient background level with shutter speed) and the gun (which adjusts the flash output power). Use it in daylight too, for straight fill when shooting into the light. Looks great. Engage HSS high speed sync and the camera sorts out any x-sync problems. There is so much you can do with a bit of experience and technique. I could go on... :D
 
Last edited:
HoppyUK said:
With a little bit of effort and learning, good flash technique will transform your pictures :)

It's important to understand how these diffuser things work. Basically they all diffuse the flash which means they redirect it in various directions, or usually all around. The light then bounces back from the surroundings, mainly the ceiling, which then becomes a much greater surface area so the light is a lot softer. In addition, some light will go directly from the flash to the subject.

In this way, if you balance things up properly, you will have most of the light coming down nice and soft from the ceiling, plus a bit of direct fill-in that lifts shadows from under eyes and chins, and puts a sparkle in the eyes. It's a great combination - called bounce/fill - but without reflective surrounding for the light to bounce off, these attachments do virtually nothing. For example if you use a Stofen outdoors, all you are doing is squirting light into nowhere, wasting power, and gaining absolutely nothing. By the same token, they are all highly dependent on the surroundings and TBH they are all much of a muchness. For example, don't believe all the marketing guff that Mr Fong puts out, he is very economical with the truth ;)

I use two flash diffusers - a Stofen because it so easy, cheap and robust. Get a white one. Most of the time, it works very well - except outside.

Which is why I really like the Lumiquest Quik Bounce which is about £40 http://www.lumiquest.com/products/quik-bounce.htm When used outside or where there are no bounce surfaces, you still get a useful amount of softening (because it makes the flash bigger) but it doesn't waste any light blasting away behind you like some others.

Then when you want to do bounce-fill, you have a lot of control with the little trap-doors and you can vary it still further by zooming the flash head. In that way, you can get the right bounce-fill ratio even with quite high ceilings etc. Plus you can flip it vertical or horizontal in, erm, a flash.

Finally, get a CTO gel, which is light orange. When shooting in normal room light, it adjusts the colour of the flash to match the ambient for correct colour. You can even use the cellophane wrapper from a box of Quality Street and get a half decent result ;)

Shoot in E-TTL - it's a doddle and works a treat. Learn how to further adjust the ambient and flash exposures by shooting in Av with +/- compensation on both the camera (which adjusts the ambient background level with shutter speed) and the gun (which adjusts the flash output power). Use it in daylight too, for straight fill when shooting into the light. Looks great. Engage HSS high speed sync and the camera sorts out any x-sync problems. There is so much you can do with a bit of experience and technique. I could go on... :D
Click to expand...

Thank you! :) That explains alot. I got the impression from Gary Fong that his Lightsphere can be used to bounce with no dome, then bounced with the dome attached, then bounced forwards with his "chrome dome" haha :D Now that I checked his prices too, I understand how much of what he says can erely be a sales pitch.

Another question would be that in AV mode to control ambient light, is there the risk of the shutter speed getting quite low? What sort of shutter speed and iso should I be looking to aim for when shooting flash indoors?
 
R.Y.K. LEE said:
Thank you! :) That explains alot. I got the impression from Gary Fong that his Lightsphere can be used to bounce with no dome, then bounced with the dome attached, then bounced forwards with his "chrome dome" haha :D Now that I checked his prices too, I understand how much of what he says can erely be a sales pitch.

Another question would be that in AV mode to control ambient light, is there the risk of the shutter speed getting quite low? What sort of shutter speed and iso should I be looking to aim for when shooting flash indoors?
Click to expand...

G Fong's kit works, and works well TBH. But it's big and cumbersome and expensive and looks ridiculous. Whereas that Lumiquest Quik Bounce only looks slightly ridiculous and folds away flat, plus it's more controllable and doesn't waste any light. (You need something big to soften the light direct from the flash head, so looking a bit daft is unavoidable really - you should see me with a 30in brolly stuck to the camera! :eek:)

Yes, if you shoot on Av then the shutter speed will go as long as it needs to match the ambient. How low is too low depends on subject movement and also movement in the background. Your judgement call, but I'm happy to run down to 1/15sec or so for social situations.

If it's getting longer than that, I switch to Manual to lock it at that level but know that if the ambient needs lower still then it will go dark. If that's unacceptable, then lower the f/number or raise the ISO. In practise, if you're using bounce-fill in a normal kind of room, the bounce light fills quite a wide area so the influence of the ambient light is less. Always keep a close eye on the LCD and monitor things. The biggest variable is usually the direct light part of the flash which is very sensitive to distance (inverse square law) which is where E-TTL is so beneficial.

At the other end of the scale, shooting outside in daylight, the shutter speed will often want to rise above the x-sync max, which is where HSS is such a brilliant invention. It's mostly fully automated so you just switch it on and forget it, but check your camera and flash handbooks to see how they interact. This is where the efficiency of the Lumiquest really pays off, as the HSS modes uses tons of power and you can't afford to have light blasting out of the back into nowhere.

BandyQuill said:
this is of interest to me, you say AV mode, when i focus on the subject it doesnt seem to change the shutter speed to be faster to cope with the flash and i just get a slow shutter speed :confused:
Click to expand...

In Av, the shutter speed will track the ambient light level as it would normally. The flash output is then moderated to balance it. With Canon, there's a custom function that will lock the shutter speed in Av to the max x-sync speed whenever the flash is on. But the backlground will probably go pretty dark.

Or you can switch to P in which case the camera will allow the shutter speed to drop to 1/60sec to match the ambient light, but not any further to minimise possible movement blur. It decides for you that a darker background is preferable to a blurred one.

Manual gives you total control of course, but in that mode you are not making best use of the camera's automation which is so useful in this kind of situation where you are basically trying to balance two different exposures (flash and ambient light) in social situations that are often quite fluid and generally distracting.

That why I use Av (I think most people do, most of the time) and keep and eye on the LCD, the shutter speed, and the flash/ambient balance. That way it's really easy to keep on top of things and adjust everything pretty much with the +/- compensation controls on both the camera and the flash, which work independently to moderate the flash and ambient exposure levels.
 
I use the Lambency 'clone' works great for me, except for looking a bit of a Dick - no change there then -(Apologies to all the Richards out there).

Not used the Whale tail version which looks horrendous.

Folk normally post at this point about cut down milk cartons and such like.

I think there is a site for a betterbouncecard which started life as a DIY thing but now has developed into something he sells.
 
BandyQuill said:
how do you set the custom functions, just had a look on my lunch and i cant see any of them that relate to setting the AV shutter speed :S
Click to expand...

Av mode can only set the aperture, and the shutter speed sets itself depending on amount of light that is available. I think the other setting is in the custom functions/flash. I had a look too and it said flash sync - auto - 1/200, 1/60, auto - 1/200 fixed. Is that the setting that we are talking about, or am I barking up the wrong tree?

I noticed that when I attach my external flash in manual mode, the camera has given me these values - shutter 1/60, xx aperture (I set mine to as wide as possible), and even in auto ISO, the ISO is on fixed 400. Is this normal?
 
john-oh said:
I use the Lambency 'clone' works great for me, except for looking a bit of a Dick - no change there then -(Apologies to all the Richards out there).

Not used the Whale tail version which looks horrendous.

Folk normally post at this point about cut down milk cartons and such like.

I think there is a site for a betterbouncecard which started life as a DIY thing but now has developed into something he sells.
Click to expand...

What's the best way to use this type of diffuser? Is it strictly "point straight up and dome/no dome" or is there other ways to use it. I've checked out the Lumiquest that was mentioned earlier in this post and it bounces off its own white backing. I don't understand how the bounce effect works on the sphere type. Does the light just spill 360, and wouldn't the attached dome just bounce the light right back down into the flash itself?
 
I tend to use the settings here :


quickreferencecard.jpg
quickreferencecard.jpg




Should be possible to print this out as a 4*6
It's down to experimentation really.
 
john-oh said:
I tend to use the settings here :


quickreferencecard.jpg
quickreferencecard.jpg




Should be possible to print this out as a 4*6
It's down to experimentation really.
Click to expand...

That's brilliant John, much appreciated! :) I've saved the image, will take a closer look tonight.
 
By the way, is the settings a rough guideline to both the clear and the cloud dome?
 
You need a bit of knowledge and experience to get the most out of any of these accessories.

There is no 'right way' to use a diffuser. They are all basically the same, but work slightly differently. The thing to remember is that they all depend on the surroundings to do the bounce-fill thing, and it is the bounce element of that which provides the most benefit. There is a 'best way' to use them, but that varies according to the situation, the variables that you can control, and the effect you want.

Flash is not like regular picture taking. With normal ambient light shooting you work with whatever nature has provided, but with any kind of artificial light you need to both create the light, and then shape it and control it as best you can. It is a key skill, very much down the the photographer. Anyone that knows what they are doing will be able to create almost identical effects with pretty much any of the many diffusers available on the market - it's not the device, but who's using it and how they adapt it to the surroundings and the subject.

Three fundamentals you need to know:
a) The bigger the light (relative to the subject) the softer the shadows. The sun is a huge light source, but it is a long way off so, relative to us down here, it is small and casts harsh, dark shadows. But when it is diffused through cloud on an overcast day, the cloud cover becomes the light source and that is huge, all around us, and shadows are very soft or almost non-existant. It's the same with flash - small gun, small light area, harsh shadows. Bounce it from or through a brolly, or off the ceiling, and that then becomes the light source and is obviously very much bigger and therefore softer. But move that brolly further away, the light becomes relatively smaller and the shadows get harder again, like the sun.
b) Brightness falls away rapidly over distance. It's the inverse square law which says that if you double the distance, the brightness is reduced to one quarter - that's two stops. So, if you have a person 1m away who is correctly exposed, then somebody else just 2m away will be two stops darker, and another 2m behind them will be another two stops down - four stops total difference. So over a range of just 1-4m, the range of brightness will go from correct exposure to almost darkness. You can use that to your advantage but if you try and fight it, such as trying to recover the under exposed areas in post processing, you will lose heavily.
c) The angle of incidence equals the angle of reflection. That is, light bounces off a flat surface at the same angle that it strikes it - like a snooker ball bouncing of the cushion. That is vital knowledge when you are bouncing light off the ceiling or a wall, or positioning a reflector.

That maybe sounds simple, but when you mix them all up together in different situations, the permutations are endless and it takes experience and judgement to get the best result. There is no shortcut, and no single device used in a certain way that will always be perfect. As a starting point, it might be an idea to just get a simple Stofen and use that. It will work pretty well in many situations and will deliver a decent result without much need for experienced input. Then look at what you've got, work out what's happening, and how you might do it better :thumbs:
 
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