Early morning ramblings about CLS

[chanjyj]

Went to an exercise corner just now, after hearing so many wonderful tales about Nikon CLS system, eg. 12 Sb-800s and an Iceberg, I decided to try my hand out at it and ditch studio strobes for a change... BAH

Seemed like I was either doing something wrong, or the SB-800 couldn't match up to a strobe at TWO FEET. I was really disappointed. Looking back at the million pictures I took, seems like the light spilled downwards instead of forwards when using an umbrella.

The umbrella was opaque-translucent (not the sole shoot through kind), but the distance to target was 2 feet. Very close, for those of you people who are not used to the metric system.

Disappointing night. I was hoping to ditch my strobes for the lighter weight CLS system, for SMALL shoots. Seems like I may not be able to do that anymore. Sad.

[sulhan]

Hiee...

Look slike you have used a translucent umbrella hoping to get a diffused reflectivity?
Hmm...I may be wrong here...but if you want to use an umbrella ..a translucent one ...here,
you would probabaly use it with the umbrella facing the other way round then the umbrella surface will glow....

From your setup, about ~2/3 of the light would have gone to space .......refracting through the translucent brolly...leaving 1/3 reflecting to the subject.

If you want to use the umbrella that position, then it should probabaly be an opaque white or Silver one i guess...

[chanjyj]

Originally Posted by sulhan Hiee... Look slike you have used a translucent umbrella hoping to get a diffused reflectivity? Hmm...I may be wrong here...but if you want to use an umbrella ..a translucent one ...here, you would probabaly use it with the umbrella facing the other way round then the umbrella surface will glow.... From your setup, about ~2/3 of the light would have gone to space .......refracting through the translucent brolly...leaving 1/3 reflecting to the subject. If you want to use the umbrella that position, then it should probabaly be an opaque white or Silver one i guess...

No. My umbrella is not a shoot thru umbrella. It is the opaque white one. Seems like the SB-800 firing at full power is able to light up the umbrella pretty darn well.

But that wasn't really my point... why was the light falling downwards instead of forwards? Translucent or not, the power cannot be that bad until the light falls off beyond 1 metre!

[psychobiologist]

your umbrella is translucent.. good for softening harsh flashes, but not for maximal output given your pitch dark conditions.

many diffusers cause light loss anyway, but in a scenario like this needing good even flash than a concentrated region, try a big bounce card. its just like shooting in an enclosed room at 12mm head-on flash, vignetting at the sides unless flash is diffused with a light sphere, or an omnibounce with a couple stops increment in flash ouput

[sulhan]

Ok...heres some thing that my help explain what i'm thinking...





hope this helps...sketching at 2am...

Your Opaque may not be opaque enough...there seem to be quite a glow!!!....an indicator of strong refraction...

[dankar]

Your umbrella is definitely a white shoot-through. So much of your light generated by your flash is lost. Get a convertible umbrella, you get the option of shoot-through and bounce.

My pairs of SB800 have replaced my studio strobes for certain assignments. I have a softbox (Photoflex LiteDome xs Kit 1) that is meant for my SB800, the other SB800 is fired directly at a white board for diffusion (normal A1 size cardboard).

Gone are the days when my strobes and all the supporting equipment have to be lunge along. Easier on the back and neck.

[chanjyj]

hot damn! if my this umbrella is considered translucent, then my other one must be transparent

Anyway feeling less mad after a night's sleep
think this umbrella can be used for indoor shots-A giant bounce card if you wish-much of the light shoots through the umbrella and hits the ceiling, the other half bounces forward

[chanjyj]

Originally Posted by sulhan Ok...heres some thing that my help explain what i'm thinking... hope this helps...sketching at 2am... Your Opaque may not be opaque enough...there seem to be quite a glow!!!....an indicator of strong refraction...

Wow.. you drew these yourself? thanks!

thinking of it maybe the reason I have of the light falling downwards (as per first illustration) is that my studio strobes are mounted closer to the centre of the umbrella, hence the light is thrown further.

when the SB-800 is mounted, the light is further away from the centre of the umbrella (as illustrated) thus the weird light angle. Hmm

[dankar]

Originally Posted by chanjyj hot damn! if my this umbrella is considered translucent, then my other one must be transparent Anyway feeling less mad after a night's sleep think this umbrella can be used for indoor shots-A giant bounce card if you wish-much of the light shoots through the umbrella and hits the ceiling, the other half bounces forward

Due to the miserly low guide number on our SB flash unit as compared to the studio strobe, you would want to maximize the available light with a bounce, softbox or direct, instead of a shot-through umbrella.

Hope this help.

[chanjyj]

Originally Posted by dankar Due to the miserly low guide number on our SB flash unit as compared to the studio strobe, you would want to maximize the available light with a bounce, softbox or direct, instead of a shot-through umbrella. Hope this help.

In essence, my Sb-800s cannot replace my studio strobes

Back to lugging my 500W stobes, stands, umbrellas and soft boxes around.

[catchlights]

Originally Posted by chanjyj In essence, my Sb-800s cannot replace my studio strobes Back to lugging my 500W stobes, stands, umbrellas and soft boxes around.

how can a hotshoe mount flash be more powerful than a 500ws stobe??

[chanjyj]

Originally Posted by catchlights how can a hotshoe mount flash be more powerful than a 500ws stobe??

When you are shooting closer than 3 feet, I would have thought it could.

[ExplorerZ]

Originally Posted by chanjyj When you are shooting closer than 3 feet, I would have thought it could.

the distance from the photo definitely looks more than 3feet to me.

[catchlights]

Originally Posted by chanjyj When you are shooting closer than 3 feet, I would have thought it could.

still, a strobe will be more powerful than a hotshoe flash for that distance,
for hotshoe flash, you may get f22,
and a strobe, you get f90.

[b18]

Originally Posted by catchlights how can a hotshoe mount flash be more powerful than a 500ws stobe??

1 SB-800 have around the same power as a 250Ws flash unit.
If you want 2, just tie 2 of them with a rubber band or gaffer tape.

and make sure you do not cover the sensor

[chanjyj]

Originally Posted by b18 1 SB-800 have around the same power as a 250Ws flash unit. If you want 2, just tie 2 of them with a rubber band or gaffer tape. and make sure you do not cover the sensor

Cannot be lah.. I think the most 80-100ws.

[hacknet]

btw, what iso and what aperture?

i've been quite happy shooting in pretty dark places at iso800 with my 50 1.8 wide open.

[chanjyj]

Originally Posted by hacknet btw, what iso and what aperture? i've been quite happy shooting in pretty dark places at iso800 with my 50 1.8 wide open.

Because you are using ambient light-I am planning to use this setup for small scale night shoots, rather than carry studio strobes around. looks like I'll hve to scrap the idea because 1. SB-800 simply not powerful enough 2. Sb-800 does not sit directly near the centre of the umbrella, so the light angle is rather weird.

[dankar]

Originally Posted by chanjyj Because you are using ambient light-I am planning to use this setup for small scale night shoots, rather than carry studio strobes around. looks like I'll hve to scrap the idea because 1. SB-800 simply not powerful enough 2. Sb-800 does not sit directly near the centre of the umbrella, so the light angle is rather weird.

Why not try this?
- Two or more SB800s off-camera should help with the 'lack of light'
- Position a non shoot-through umbrella angle slightly higher to compensate for the light spread coverage and also to help channel 100% of the light back to the subject
- Mount the SB flash head straight instead of 90 degrees, that would allow the centering of your flash unit to umbrella

My 2-cents worth. I am sure your neck and back would appreciate the lighten load...

[chanjyj]

Originally Posted by dankar Why not try this? - Two or more SB800s off-camera should help with the 'lack of light' - Position a non shoot-through umbrella angle slightly higher to compensate for the light spread coverage and also to help channel 100% of the light back to the subject - Mount the SB flash head straight instead of 90 degrees, that would allow the centering of your flash unit to umbrella My 2-cents worth. I am sure your neck and back would appreciate the lighten load...

I did think of using my reflective umbrellas, but hesitated because worried that light would be very harsh, almost like a direct flash. But never mind about that.

How to mount straight instead of 90 degrees? I am currently using the nikon SB-800/RC-1 flash mount that came with the flashgun, which I attach to the tripod.