Advise sought for "darkening with light" technique

[kilkenny]

Hi catchlight,

I did read up on the inverse square law, what i took away from it was that intensity of light doubles up if the distance is halved. ;p it does help me but i need more practise i guess. I already read up on guide number as recommended by YSLEE and i think its a mathematical intepretation of inverse square law for flash so tt helped a bit more.

Hi jonkk,

Lovely examples. Tks, especially love the one on cheryl. Can i check if all the photographs was achieve using off camera flash? Tks.

Hi YSLEE,

Thanks. The tip was great. I am using a D90 and the guide number for the internal flash is 12 metres. However the rating is for ISO100 which D90 does not have and i always shoot at ISO200, does tt half the guide number?

Thanks all for the reply and advise.

Cheers,
kilkenny

 

[catchlights]

are you shooting with the built in flash on TTL mode?

 

[kilkenny]

yupz.

cheers,
kilkenny

 

[catchlights]

ok, since your subject is part of a black background, and the black assort light, so the camera meter tell the flash to output more light, and at the same time will open up the aperture or shutter speed if you are not on camera manual exposure mode.

the results? subject overexposure and black background turn gray.

suggestion: go and read this book before you keep trying trying and trying and still not sure what went wrong.

 

[kilkenny]

Hi catchlight,

Thanks for the tip. Will try to source out the book or find more online materials on exposure. Actually i am not on auto mode, i have tried out shutter priority, aperture priority and manual mode. However on all occasion my subject is just infront of the backdrop as i am working in space constraint. ;p

Thanks for the effort to clarify my doubts so far. Will read more and try to understand where i went wrong! :sweat:

Tks.

cheers,
kilkenny

 

[jonkk]

UNDERSTANDING EXPOSURE BY BRYAN PETERSON IS A GREAT BOOK.
A must read for all those starting photography. Also by him,
LEARNING TO SEE CREATIVELY.

Check those out.

And yes, all were photographed using off-axis flash lighting.

 

[jonkk]

Thanks for the kind words mate

Anyways - if you're using on-camera flash.. you can still achieve the effect of killing the ambient light. However, you will have hard light with harsh shadows. A suggestion is to try use available light, such as shooting a person in the shade, with the main light coming from the outdoors. If it's not bright enough, use the on-camera flash to fill.

 

[kilkenny]

Noted!

Nvr tried using ambient light yet, have been experimenting in a dark room with no ambient light :think: figured taking something out of the equation would be a shortcut method but thanks for highlighting that i need off camera flash.

Even i got a studio light but it still is being triggered by the in built flash from my D90 which does cast harsher light on the subject. hahaah

no time to experiment these few days hahaha have to wait till wkend :cry:

tks all.

cheers,
kilkenny

 

[catchlights]

you can achieved the black background effect with your built in flash, but the lighting effect from the built in flash is flat, very flat, very very flat, the portrait will be like what Ang Moh photographers always describe as "deer caught in car head light" or "shooting in the cave".

if this is what you want, just make sure the distance of your camera to your subject, same or greater then the distance from your subject to the black velvet cloth, set your shutter speed at max sync speed, set flash on manual mode, shoot a couple of photos, adjust the flash output till you get correct exposure on your subject FACE, the background will be completely black out.

 

[catchlights]

btw, you miss out the "s" in my nick. without the "s", that is another person.

 

[kilkenny]

"deer caught in car head light"

i like this expression ahhaah very adequate :thumbsup:

set your shutter speed at max sync speed

Your saying this means that there is no way i can get around the maximum shutter speed of 1/200? is there any way to override it? cos even if i get a SB600, it need to be triggered by the internal flash so my shutter speed will still be that? Any advise? Tks.

btw, you miss out the "s" in my nick. without the "s", that is another person.

hahaha sorry for missing out on this detail

cheers,
kilkenny

 

[catchlights]

...........................



Your saying this means that there is no way i can get around the maximum shutter speed of 1/200? is there any way to override it? cos even if i get a SB600, it need to be triggered by the internal flash so my shutter speed will still be that? Any advise? Tks.

..............

since you only want the subject lit by your flash, and not to let the ambient light affect your images, you can increase your shutter to max sync speed, don't need to dim down/black out the room unless it is extremely bright.

anyway, the max sync speed for D90 is 1/250s, I think to set up off camera lighting or off camera lighting, it is too complicated for you at this stage.

you need to brush up your basic knowledge on photography first, before you want to do something more advance.

hope this help.

 

[kilkenny]

since you only want the subject lit by your flash, and not to let the ambient light affect your images, you can increase your shutter to max sync speed, don't need to dim down/black out the room unless it is extremely bright.

anyway, the max sync speed for D90 is 1/250s, I think to set up off camera lighting or off camera lighting, it is too complicated for you at this stage.

you need to brush up your basic knowledge on photography first, before you want to do something more advance.

hope this help.

Roger! learning is part of the fun too.

cheers,
kilkenny

__________________

 

[YSLee]

Dude,

Judging by your question to me you still don't really understand how the formula for GN works.

I'm feeling generous today so I'm going to spoonfeed you a little.

GN is affected the following way:

For every stop in aperture from f/1.0, divide or multiply the number by a factor of 1.4.

For every stop in ISO from the stated ISO, double or halve the number

When do you double or halve? Well, a flash generates light, and the above two settings change the effects of light on the final exposure, so a flash is more effective when...?