Flash compensation after diffusing it


Status
Not open for further replies.

yeocolin

New Member
May 2, 2003
816
0
0
41
Singapore
www.flickr.com
Hi,
I understand many of us use Stofen Omnibounce or a white card as a diffuser instead of using the flash directly on our subjects to prevent a 'wash-out' effect.

May I know what is the flash compensation you use after diffusing in indoor/low light situation. Please also specify how do you do your diffusing, since the different modes of diffusing flash means different degree of light loss.

Thanks.
 

yeocolin

New Member
May 2, 2003
816
0
0
41
Singapore
www.flickr.com
I'm using TTL.

Some flash units have wide angle adaptors. I know mine has. How do they serve as a diffusor?
 

NiVleK

New Member
May 15, 2003
824
0
0
Jurong West
daddy.nivlek.per.sg
If you are using ETTL flashes, it should be all automatic. A preflash b4 the main flash measures the amount of flash to fire. Compensation should not be neccessary unless the reading is screwed up.
 

clive

Senior Member
Oct 9, 2002
2,536
0
0
Visit site
for indoor lowlight events i simply mount the omnibounce and tilt/or shoot straight and set -1 n 1/3 flash comp
 

showtime

New Member
May 2, 2003
984
0
0
42
Singapore
Visit site
yeocolin said:
I'm using TTL.

Some flash units have wide angle adaptors. I know mine has. How do they serve as a diffusor?
since you are using ttl, there is no need to compensate... the flash will compensate it for you.
 

jimtong

Senior Member
May 8, 2002
1,544
0
36
Singapore
jimmyto.ng
if you are using digital cam. The best is to review the photo then adjust the flash accordingly to suit your taste.
 

showtime

New Member
May 2, 2003
984
0
0
42
Singapore
Visit site
you mean to preview it on the lcd and make your judgement on flash accuracy based on that? i dont think thats a good idea beacuse the lcd on the camera is not accurate enough for one to make such a decision.
 

yeocolin

New Member
May 2, 2003
816
0
0
41
Singapore
www.flickr.com

jimtong

Senior Member
May 8, 2002
1,544
0
36
Singapore
jimmyto.ng
showtime said:
you mean to preview it on the lcd and make your judgement on flash accuracy based on that? i dont think thats a good idea beacuse the lcd on the camera is not accurate enough for one to make such a decision.
yes but at least you can differentiate whether you have a underexpose pict by looking at the histogram.

the tools is there, use it. Better then nothing.
 

mervlam

Senior Member
Apr 26, 2002
2,279
0
36
Visit site
clive said:
for indoor lowlight events i simply mount the omnibounce and tilt/or shoot straight and set -1 n 1/3 flash comp
really depends on the kind of event and the space around it.... doesn't work for all situations
 

ST1100

Senior Member
Jun 18, 2003
1,784
0
36
Singapore, Bedok
showtime said:
you mean to preview it on the lcd and make your judgement on flash accuracy based on that? i dont think thats a good idea beacuse the lcd on the camera is not accurate enough for one to make such a decision.
The review in this context is not so much for judging exposure but for how accurate the flash is, typically, how strongly/accurately lit the foreground (flash subject) is wrt to the entire picture. The histogram is not as helpful in this case bcoz it carries the data of the entire scene mixed in.

You can still guess which spike in the histogram corresponds to the main subject, but it's hit and miss guesswork when there are multiple spikes, or worse, no spikes.

Despite its inaccuracy, i would say that using the lcd review is (usually) more useful than the histogram is judging flash accuracy, unless your flash intention is to light the entire scene (ie no background, eg newspaper pinned on wall).
 

TME

Senior Member
Jan 19, 2002
6,579
0
0
44
Clementi
Whether u compensate or not even with TTL also depends on how contained an area your subject is in.... just shooting last week in a small dining room and rather dim (tungsten warm light), and I bounced the flash off the ceiling (ceiling about 12-15 feet high, flash head almost vertical) and my shots were very well-exposed (no hotspots)but the whole shot's lighting became like white lighting rather than the warm tungsten light... in this case, me thinks the space was small and the flash was very powerful and so the entire space (read background, foreground) was lit by the flash... not unpleasant but kinda lost the atmosphere....
 

weg

New Member
Jul 10, 2002
660
0
0
40
WSSS
www.kelvinseow.com
i've noticed on my sigma 500dg super that whenever i use omnibounce or lumiquest, i have to have -1Ev flash compensation to get the same results as flash without any attachment and 0 flash compensation.

Rather puzzled by it since i tot eTTL shld factor in the omnibounce,,,..
 

HOCL

Member
Jan 30, 2002
492
0
16
NE
Visit site
I thot iTTL shd do that too ... my experience was the opposite ... shooting at home with SB800 requires +1EV with the diffuser ... :(
 

TME

Senior Member
Jan 19, 2002
6,579
0
0
44
Clementi
Your flash might not be very compatible with the camera body especially the Sigma... or the calibration of the TTL sensor is off. Other factors may be the reflectance and colour of the background, etc and the metering mode of the camera.
 

djork

New Member
Jul 14, 2002
1,157
0
0
Hong Kong, Pokfulam
Visit site
HOCL said:
I thot iTTL shd do that too ... my experience was the opposite ... shooting at home with SB800 requires +1EV with the diffuser ... :(

hey you're not alone. i realised the 550 on the 300d needs +1EV for my needs too.
 

nightwolf75

Moderator
Staff member
Dec 18, 2003
17,926
30
48
really MORE diaper changes
weg said:
i've noticed on my sigma 500dg super that whenever i use omnibounce or lumiquest, i have to have -1Ev flash compensation to get the same results as flash without any attachment and 0 flash compensation.

Rather puzzled by it since i tot eTTL shld factor in the omnibounce,,,..
u using 300D? on my 300D, i need to +1EV when using the bounce with my sigma 500DG Super. or else my pics will be under. i suppose if u are using the canon EX 550 flashes, it will not have the problem.
 

Status
Not open for further replies.