Flash Diffusion Question

[Spinners]

When shooting with my new strobe kit, i find i burn the subjects alot. I use my meter in non-cable mode, take a reading, and set the camera to that reading.. i then step the flash down about .5 or 1 whole stop (if the subjects are above normal reflectance) this however does not seem to solve the burning issue all the time.

I can only drop the flash so many stops. In alot of articles i have been reading i notice people using diffusers over there flashes.. so my question.. finally..

are diffusers the equivalent of stepping down flash, or do they do something more magical. ? Any suggestions would be great.

[Pekka]

Diffusers distributes light to a wider area (from wider source area) so shadows get little softer .

The flash has to output more power (metering does not know if diffuser is on or not) so essentially amount of light does not reduce, it's just not as harsh. With diffuser flash does not reach as far so diffusers are good for relatively close distances only.

If you burn subjects a lot then you may need to practice some ETTL FEL stuff, or just take care that subject does not reflect excessively (e.g. when doing portraits use powder on men, too :))

[Spinners]

Well i was shooting a bride and groom that let me take some shots of them with my new kit. I was not using my 420EX flash, only my external setup. So E-TTL cannot be used (at least to my knowledge.)

I also find histograms, not very reliable is flash situations. Especially since your going to have a darker background. So you really dont know what your getting till u upload it. (or did i miss something)

[Yance]

Ideally you should have a handheld incident meter. What in-camera metering are you using? I think your camera should have a spot mode so you can center it on a face or zoom in on the face of someone and meter it that way. Flesh tones are generall a little brighter than 18% unless they aren't caucasian. So stop down approx 2/3 of a stop after metering a caucasian skin tone. Generall with a hand-held meter I go with the incident reading.

If your flashes are still too bright when set to minimum power you may want to consider either moving them farther away or using a neutral density gel on the lights. Using an umbrella or bouncing the lights as opposed to direct flash will also reduce the output.

[Spinners]

I was using an incident meter. I was metering F8 at 1/60. I then stepped my flash down 1.5. Still burned them. Not their skin, but the brides dress. Blows my mind, because i can step my 420EX down a half step for handheld shots. works fine. Probly apples to oranges though.

I dont suppose the camera sends any thing about exposure to the external lights? They are truly dumb lights right?

[Spinners]

As for 2/3 of a stop.. you mean using the external flash system right? i can tell my external flash system to step down up to 4 stops.. or do you mean actually change my physical f stop? if thats the case, how do i get 2/3 of F8?

[daveh]

spinners wrote:
if thats the case, how do i get 2/3 of F8?

F10.

You have a 10D right? In that case, set the custom function that selects 1/3 stops (default is 1/2) and dial 2 clicks past F8.

[Spinners]

daveh,

are you implying that i should adjust the flash by a stop, but actually change my aperature?

[Spinners]

I meant shouldnt adjust my flash a stop.. :)

[Spinners]

i have to stop thinking of things after i post.. i thought Fstops were based on your lense? i dont recall seeing F10 as an option. i think u just lost me, or i lost myself, sigh... :(

[daveh]

Um, well you can do either or both. It's up to you. The point is to create the kind of image that you want. I was just answering a technical question which is much easier.

I'm sure your lens does f10 (though you haven't told me what it is.) Try it.

[Spinners]

I will check my lenses out tonight and see if it has f10. I shoot with a canon 24-28mm and a sigma 28-300mm. Not very fond of the sigma. but it performs ok.

All this leads me to another question. Proper shooting height? Know of any good books that talk about it? or any online resources. Non of the books i've read so far really touch on proper picture height.

[Yance]

You should be able to set the camera to adjust in increments of 1/3 stop. Hell my G1 even is set for it! Really a third of a stop doesn't make too much difference so go for a full stop if you want. The thing with the brightness of the bride's dress is very difficult. Most dresses are satin which reflects even more light back. If you are shooting wide, override the zoom setting of the on-camera flash and set it to manual. Zoom it to 70mm and aim it towards the faces. Don't give the dress the same amount of light as the faces or it will always be overly bright. And the same with the Novatrons - gobo them so they don't light the dress. You should get enough spill to keep them from being dark.

Proper shooting height??? There is no such thing. If you are talking about portraiture it will actually vary. You want to adjust the angle to be flattering. Don't shoot to emphasize flabby necks or bald spots or look up someone's nose. Especially where a bride is concerned, if you show too much body fat you will probably die a painful death. If possible try various heights with different people to determine the most flattering view. It comes with practice. A general rule of thumb is eye level but that doesn't always work.

[Spinners]

Gulp... thanks for the tips yance.. how do i use gobos with my novatrons.. i have them up high with the umbrella doohickies. should i not be shooting that way?

[daveh]

You can use a fancy schmancy, "photographic clamp", or you can use duct tape, or anything in between. Whatever works.

[Yance]

Sorry, I guess flag is probably the correct terminology. You can use anything to block the light from hitting where you don't want it. A black card of some sort is typically used and yeah it can be duct-taped to another light stand or anything in between the light and the subject. Lowel makes plenty of light stand attachments, flexishafts and smaller flags. To get all of the light shaping accessories needed can be expensive so you may want to just improvise.