omnibounce straight on?


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Jun 20, 2006
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#1
hey all,

why do I see some pros using omnibounce strsight on? I thought should use it 45degrees? How does using omnibouce straight on helps?
 

fireframe

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Dec 5, 2003
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#2
why do I see some pros using omnibounce strsight on? I thought should use it 45degrees? How does using omnibouce straight on helps?
If the ceiling is not low enough for the light to bounce back, using it angled might mean you don't have enough light to get your shot. Straight-on may not look that good, but you get your shot. ;)
 

catchlights

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Sep 27, 2004
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#6
Sorry, i dun understand.

if you are outdoor, there is no way to bounce the light, hence can only fire straight on mah
if you are shooting bugs, omnibounce may enlarge the flash from tiny pointed light source to a bigger one, so may soften the light a litter,

but you are shooting humen or whatwhoever bigger subjects, since no way to bounce, hence no point of shooting it with omnibounce straight on, some people still attach the omnibounce on the flash, maybe they have no place to keep it, or know that the flash still deliver sufficient flash light.
 

ioriroger

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Oct 12, 2005
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#7
i leave my omnibounce 90deg most of all the time.;p(i do not push omni all the way in i leave it more than a half out) when shooting indoor or outdoor(potrait)

coz i found that it can forward more softer light & fill the whole smaller room wit light too;p
. snaping photo just part of my hobby;) sorry if i'm done wrong in this way coz i'm not a exp photographer, i also want to know wat is the better way to using omni bounce. cheer!

 

Aug 9, 2006
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#8
From stofen site, it says:


"Q: Why must I tilt the flash head to 45 degrees?

A: In Non TTL models this is necessary to avoid under exposure caused by light from the Omni hitting the external auto sensor of the flash. In TTL models it gives a better feathering wrap around of the light in the range from close to about 15 feet from the subject. Beyond that point with TTL we find straight on works OK for you. "
 

zac08

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#9
From stofen site, it says:


"Q: Why must I tilt the flash head to 45 degrees?

A: In Non TTL models this is necessary to avoid under exposure caused by light from the Omni hitting the external auto sensor of the flash. In TTL models it gives a better feathering wrap around of the light in the range from close to about 15 feet from the subject. Beyond that point with TTL we find straight on works OK for you. "
Correct. With a TTL system, the flash actually knows when there is enough light reaching the subject and you can actually point the flash (with a Omnibounce) directly at the subject.

Else if we point it at 45° or 90°, there would be even more light loss when there is nothing (low ceiling or wall) to bounce from.

Normally, I'll also dial in a negative exposure (-0.7 to -1.7) for the flash to get a more even lighting. ;)
 

varf

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#10
Correct. With a TTL system, the flash actually knows when there is enough light reaching the subject and you can actually point the flash (with a Omnibounce) directly at the subject.

Else if we point it at 45° or 90°, there would be even more light loss when there is nothing (low ceiling or wall) to bounce from.

Normally, I'll also dial in a negative exposure (-0.7 to -1.7) for the flash to get a more even lighting. ;)
i apologize if this sounds rude, but your statements are more confusing than the explanation you just quoted.
 

zac08

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Feb 21, 2005
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#11
i apologize if this sounds rude, but your statements are more confusing than the explanation you just quoted.
Ok... let's try this.

At 45° and 90° both are directed more or less to the ceiling (best situation would be if the ceiling is about 3m/9ft or so). This would allow for the flash to bounce off the ceiling and reach the subject in front of the camera. Note that this only works if there is a ceiling low enuff and does not change the colour of the picture (a different coloured ceiling may induce colour cast on the subject)

With a TTL system, the flash knows when there is enough light directed on the subject, be it 45°, 90° or direct head on. Only difference is that the glare from the head on flash may be a lil too harsh on the subjects. This is why we experiment with bounce flash lighting (with bounce cards, LSPJ's, Omnibounce, and so on...) But these lose power when we try to bounce it off a VERY high ceiling or if the ceiling is dark and absorbs light. As such, you can opt to try to use it direct (and hope that the diffused lighting is low enough for the situation)

So for my personal usage, if I can't bounce it off any ceilings or walls. I'd use it head-on and dial in a -ev setting to compensate for the harsh glare. Hope this would be more satisfactory and clearer. ;)
 

unseen

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Dec 14, 2004
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#12
i apologize if this sounds rude, but your statements are more confusing than the explanation you just quoted.
Er.. look at it this way.. non ttl flash works by sensing if there's enough flash output, sense and adjusted by an external sensor.

Simply put, if you use omni bounce, your flash is redistributed in all areas, including downwards to where the sensor detecting preflash. When that happens, the sensor would be fooled to think that the flash is too bright (i.e. too much of the preflash was reflected though in actual fact it's leaked light from the flash), so it'll reduce the amount of flash. End up your flash is underexposed.

ETTL/iTTL works differently, it sends out a preflash. With the preflash, the camera takes in the scene through the lens and calculates if the amount of flash should be increased or decreased accordingly. Regardless of the modifier you put to your flash, the camera will send out the proper amount of flash to expose your subject properly. you NEVER need to adjust your flash just because you're using a diffuser etc, coz we're using TTL, not a sensor to calculate the flash..

That's why it doesn't matter at all which ever way you point your flash if you're using an omni bounce. it's just going to end up being a square box of light. point up it's going to be higher, point direct it's going to be lower.
 

user111

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Jul 27, 2004
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#13
just throw away the omnibounce and use direct flash:thumbsup: :thumbsup: :thumbsup:
 

laimg

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Jun 6, 2006
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#14
Asked and searched around for answer b4, and decided that
omnibounce is good also outdoor, if
1) stand within 3 m from the subject.
2) big aperture (like F 2.8 or wider) prevent over-blown faces by reducing flash output.
3) using wide prime/zoom
With 17-55mm 2.8 zoom being popular, I think omnibounce has its place in your cam bag.


just throw away the omnibounce and use direct flash:thumbsup: :thumbsup: :thumbsup:
 

varf

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#16
With a TTL system, the flash knows when there is enough light directed on the subject, be it 45°, 90° or direct head on.
ETTL/iTTL works differently, it sends out a preflash. With the preflash, the camera takes in the scene through the lens and calculates if the amount of flash should be increased or decreased accordingly. Regardless of the modifier you put to your flash, the camera will send out the proper amount of flash to expose your subject properly. you NEVER need to adjust your flash just because you're using a diffuser etc, coz we're using TTL, not a sensor to calculate the flash..
i understand the thrust of your explanations regarding the placement of the omnibounce/light modifier, but have to disagree with the semantics.

in a TTL system, it is not the flash but the sensor in the body that "knows when there is enough light".

for thyristor-based flashes, the situation with the omnibounce pointed straight ahead is explained very concisely by Sto-fen as quoted by canongrapherL's earlier response. the follow-up explanation from zac08 about TTL is somewhat superfluous and misleading.

TTL systems (or E-TTL or other variants) will also be affected by unwanted light cast from the light modifier(s) as long as the evaluating sensor can see it.
 

zac08

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Feb 21, 2005
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#17
TTL means thru the lens... And the sensor for this is on the camera.
and the flash will get the information from the camera thru the electronic contacts.

I apologise for not making this clear as I had mistakenly thought that the reader would have understood about the TTL system.

And my statement was on the choice of using it head on rather than bouncing on nothing esp in outdoors or places with very high ceiling.
 

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