Correct way to use Omni Bounce diffuser?

[satz24]

hi all

I recently bought an 'imitation' omni-bounce type diffuser to use on my Nikon SB600 flash.

This is the type that sits firmly on the end of the flash head.

WHen I use this diffuser I'm finding that the photos I take (indoors) are too bright (and too 'white') and the shadows are more harsh.

I have the flash head tilted forward just slightly from vertical.

Even when I use the WB setting for 'flash', the photos turn out too white and too bright.

I thought shadows and light should be better with the diffuser?

Am I using it wrongly? Do I need to use a different flash-head angle, and/or change camera settings?

many thanks


Satz

[FilterFunk]

http://www.stofen.com/FAQ/index.htm
it should work like the original stofen. just my 0.02..

[calebk]

Originally Posted by satz24 hi all I recently bought an 'imitation' omni-bounce type diffuser to use on my Nikon SB600 flash. This is the type that sits firmly on the end of the flash head. WHen I use this diffuser I'm finding that the photos I take (indoors) are too bright (and too 'white') and the shadows are more harsh. I have the flash head tilted forward just slightly from vertical. Even when I use the WB setting for 'flash', the photos turn out too white and too bright. I thought shadows and light should be better with the diffuser? Am I using it wrongly? Do I need to use a different flash-head angle, and/or change camera settings? many thanks Satz

If I'm not wrong, yours is the kind that doesn't pop out a little to spread the light all around right? That's why it's not getting diffused.

[satz24]

mine's exactly like this:

http://cgi.ebay.com.au/Brand-New-Fla...QQcmdZViewItem


except, of course, for Nikon SB600


thanks

satz

[catchlights]

the Omni Bounce is to tilt 60° when use in indoor, Omni Bounce itself does not soften the light, it spread the light into omni direction, so the light bounce up, left and right before reach the subjects, and the subjects have softer light and shadows.

please note that you flash will use up more power when using omnibounce, but TTL will take care of exposure, and you need to use bigger f-stop or go close to prevent underexpose due to out of range of flash power.

WB has nothing to do with exposure.

[satz24]

what I have found is almost the opposite...

when I am using the diffuser, the shadows are stronger...and the light is harsher and brighter (without any adjustment to camera)

The light is also whiter / colder!

[catchlights]

Originally Posted by satz24 what I have found is almost the opposite... when I am using the diffuser, the shadows are stronger...and the light is harsher and brighter (without any adjustment to camera) The light is also whiter / colder!

compare to what?
direct flash?
ceiling bounce?
bounce card?

the material of your "'imitation' omni-bounce type diffuser" will have effect on the WB, it is just like a filter for the flash, changes the color of the light.

[satz24]

hi


Quote: satz24
what I have found is almost the opposite...

when I am using the diffuser, the shadows are stronger...and the light is harsher and brighter (without any adjustment to camera)

The light is also whiter / colder!



....in comparison to 'bare' flash (without any addon) bounced at same angle (45deg and also approx 80 deg)

how does one correctly do a white balance for a flash? I can't use a WB card


thanks

[catchlights]

Originally Posted by satz24 hi Quote: satz24 what I have found is almost the opposite... when I am using the diffuser, the shadows are stronger...and the light is harsher and brighter (without any adjustment to camera) The light is also whiter / colder! ....in comparison to 'bare' flash (without any addon) bounced at same angle (45deg and also approx 80 deg) how does one correctly do a white balance for a flash? I can't use a WB card thanks

when you use it bare, bounce at a angle, all the light will hit the ceiling before it reach the subject, the color of the ceiling will affect the color, even the ceiling is white or neutral color, ceiling bounce will yield a warmer color compare to direct flash.

but if you use the omnibounce, some of the light travel direct to the subjects, since the light travel direct are stronger, so the colder/neutral color of the light is dominating.

[satz24]

thanks for that info, "catchlights"


I guess the only way to accurately WB (on my D50) using the omnibounce, is using PS?

cheers

satz

[calebk]

Originally Posted by satz24 thanks for that info, "catchlights" I guess the only way to accurately WB (on my D50) using the omnibounce, is using PS? cheers satz

Leave it on AWB I guess, or shoot RAW.

[scann]

just a question..newbie here...does the external flash 'knows' that the angle the flash is tilted at? And even if it does, things do change if we attach a bounce card or a omni bounce. How do we compensate ? Thanks!

[ExplorerZ]

Originally Posted by scann just a question..newbie here...does the external flash 'knows' that the angle the flash is tilted at? And even if it does, things do change if we attach a bounce card or a omni bounce. How do we compensate ? Thanks!

under "perfect" TTL, you don have to compensate...

[catchlights]

Originally Posted by satz24 thanks for that info, "catchlights" I guess the only way to accurately WB (on my D50) using the omnibounce, is using PS? cheers satz

you're welcomed.

agreed with calebk, you may adjust + or - to fine tune the auto WB to your taste.

[catchlights]

Originally Posted by scann just a question..newbie here...does the external flash 'knows' that the angle the flash is tilted at? And even if it does, things do change if we attach a bounce card or a omni bounce. How do we compensate ? Thanks!

you need not to compensate if you are shooting in flash auto or TTL mode, the flash and camera will do the calculation for you.
however, since you are using bounce card or a omni bounce, the effective range of the flash has been shorten, so you may need to get closer to your subject or using bigger aperture or higher ISO to compensate the lost for flash power.
hope this in not too confusing.

[scann]

Originally Posted by catchlights you need not to compensate if you are shooting in flash auto or TTL mode, the flash and camera will do the calculation for you. however, since you are using bounce card or a omni bounce, the effective range of the flash has been shorten, so you may need to get closer to your subject or using bigger aperture or higher ISO to compensate the lost for flash power. hope this in not too confusing.

thanks! does that mean the flash and the camera knows how high the ceiling will be if for example i point the flash right up at the ceiling?
does that mean when i use a bounce card, i will not be able to use auto mode for the camera since all calculations wil be done automatically?what i normally do is to turn my camera to manual mode and set the shutter speed or aperture so that the picture is slightly over exposed by one or two 'bars' (when u look through the camera if you know what i mean). Is that correct? I think i am more confusing. thanks again!

[ExplorerZ]

Originally Posted by scann thanks! does that mean the flash and the camera knows how high the ceiling will be if for example i point the flash right up at the ceiling? does that mean when i use a bounce card, i will not be able to use auto mode for the camera since all calculations wil be done automatically?what i normally do is to turn my camera to manual mode and set the shutter speed or aperture so that the picture is slightly over exposed by one or two 'bars' (when u look through the camera if you know what i mean). Is that correct? I think i am more confusing. thanks again!

eh, with flash you set your EV to overexpose?
shouldn't it be underexpose? else you gonna end up with a overexposed image with/without flash...

[catchlights]

Originally Posted by scann thanks! does that mean the flash and the camera knows how high the ceiling will be if for example i point the flash right up at the ceiling? does that mean when i use a bounce card, i will not be able to use auto mode for the camera since all calculations wil be done automatically?

no, in flash auto mode or ttl mode, the sensor (in flash when you are on flash auto mode, in camera when you are in ttl mode) read the flash light discharge from the flash till it reach a predetermine value and cut it off, hence the flash given a "correct" exposure.

so the flash does not know how far is the distance which the light has travel. but since you use bounce device on flash, the flash power cut down significantly, your flash have to work harder to get the same amount of exposure. in short, the range of the flash is reduce.

sometime, i see people take a shot with flash, image turn out to be underexpose, instead of open up aperture, up ISO or go closer, they use + compensation on flash!!

the flash has already deliver max power liao, still underexpose. add + compensation will not make the flash deliver more power than max!!

Originally Posted by scann what i normally do is to turn my camera to manual mode and set the shutter speed or aperture so that the picture is slightly over exposed by one or two 'bars' (when u look through the camera if you know what i mean). Is that correct? I think i am more confusing. thanks again!

this is not the right way, you set your ambient over exposed by one or two 'bar', means you are overexpose the image by 1/3 ~2/3 stops, with or without flash, you images are already overexposed. (unless your camera meter is bias or you alway meter on the highlight instead on the subject, or you want to archive a effect by overexpose it)

[scann]

hmm...since you mentioned that by using a bounce card or omni bounce would reduce the flash power since light is dispersed, the picture would be underexposed since the flash would 'think' that it is correct. By over exposing one or two 'bars' wouldn't it brighten up the picture back to the correct exposure? I mean the above scenario is used only for bounce cards or omni bounce.
if without using any bounce cards, then the flash would correctly expose pictures right? Thanks again!

[catchlights]

Originally Posted by scann hmm...since you mentioned that by using a bounce card or omni bounce would reduce the flash power since light is dispersed, the picture would be underexposed since the flash would 'think' that it is correct. By over exposing one or two 'bars' wouldn't it brighten up the picture back to the correct exposure? I mean the above scenario is used only for bounce cards or omni bounce. if without using any bounce cards, then the flash would correctly expose pictures right? Thanks again!

when you using auto or ttl mode on flash, the output of flash light is variable.
for example, you want to flash to deliver flash light at the exposure of f8, as long you stay with 1.5m ~15m, the flash will give you f8, cos the sensor read the exposure on the subject and output enough amount of light to reach f8.
but if you use bounce device on flash, the flash will still give you f8, but instead of 15m, maybe cut down to 8m, so as long you still within the "new" working range, you are safe.