Help first time bracket shoot and all overexposed

Mitchell

I just shot my first event with my new flash bracket and new SC-29 cable. Oddly, all of my photos were overexposed by about 1 stop.:scratch This was one of those scenarios where I kept checking the screen for highlights. While nothing was blinking on my LCD, most of the faces were blown when I opened them on ACR. Fortunately, I shot in RAW and salvaged all of the photos.

I'm just trying to understand where things went wrong. I've shot many events like this before in manual and kept the flash on camera in ttl. Any thoughts why this would have occured?

Straight ooc



After pp


Another

This was shot at ISO 500, f5.6, 200

SOC



After pp


<!-- / message --><!-- sig -->

aktse

I know this is a really, really dumb question.

Since you shot in TTL, did you check the FEC? Was it at +1 over where you wanted it? Knowing you, it's probably exactly where you wanted it to be.

Qarik

hmm in these 2 shots there is a lot of black clothing which may be effecting overall tonality and the metering. The flash may have been compensating for that. Do you have examples where someone is not wearing black?

Also..direct (diffused) flash? tsk tsk!

Wil Davis

I'm with Qarik; I think the black is messing things up. Also, why use a SC29 cord? I can't remember your main gear, but if it's Nikon, use wireless remote CLS; have the speedlite on the bracket as the main (group A), and use the built in flash on the camera as Commander and also as the fill (group ; meter for the background, and let the CLS sort out the flash, and tweak until good.

All the other stuff you post is just about perfect, so what gives? (I think we should be told! )



- Wil

Second Thoughts: SB600 can't be used as commander, but if you're using it on the bracket, it doesn't need to be Commander. If your camera is a D70, it can only send out flash data on Ch 3 Group A; need more detailed list of your gear to be of further help…

ziggy53

3 questions:

1) How was the flash head oriented, up with a flash modifier?

2) What lens was used?

3) Did ACR show completely unrecoverable areas in the skin tones?

Mitchell

Wil Davis wrote:

I'm with Qarik; I think the black is messing things up. Also, why use a SC29 cord? I can't remember your main gear, but if it's Nikon, use wireless remote CLS; have the speedlite on the bracket as the main (group A), and use the built in flash on the camera as Commander and also as the fill (group ; meter for the background, and let the CLS sort out the flash, and tweak until good.

All the other stuff you post is just about perfect, so what gives? (I think we should be told! )



- Wil

Second Thoughts: SB600 can't be used as commander, but if you're using it on the bracket, it doesn't need to be Commander. If your camera is a D70, it can only send out flash data on Ch 3 Group A; need more detailed list of your gear to be of further help…

I'm a newbie with a bracket, but I'm pretty experienced with CLS. Why would you suggest I fire my flash wireless on my bracket? This makes no sense to me when I have an sc-29 cable. I'm not talking about a flash mounted on a separate light stand or pole. It's on a Stroboframe bracket. Who would use a wireless setup for this?? I do have an SU800, but it seems to me that my cable should provide me with ittl performance.

Mitchell

ziggy53 wrote:

3 questions:

1) How was the flash head oriented, up with a flash modifier?

2) What lens was used?

3) Did ACR show completely unrecoverable areas in the skin tones?

1. Flash head was directed upwards 30 degrees.

2. Lens used was a Nikkor 28-70mm, f2.8 on a Nikon D700. SB800 and SC-29 cable was used.

3. I'm not sure what you mean by "unrecoverable". When I open ACR, the faces are red (showing blown highlights). When I reduce the exposure in ACR, these blown areas revert to a normally appearing image.

Mitchell

Qarik wrote:

hmm in these 2 shots there is a lot of black clothing which may be effecting overall tonality and the metering. The flash may have been compensating for that. Do you have examples where someone is not wearing black?

Also..direct (diffused) flash? tsk tsk!

Yes, many folks were wearing black, but it occured in people not wearing dark colors. The classes I've taken on ittl all stress to put the focus reticle on the face and allow the ittl to do it's thing to regulate flash output. You are correct that if you put the reticle on black clothing, the ittl will overexpose facial skin. I carefully placed the reticle on the face for these shots.

I'm beginning to wonder if my cord is defective.

Here's an example with lighter clothing.

SOC


After pp

ziggy53

Mitchell wrote:

1. Flash head was directed upwards 30 degrees.

2. Lens used was a Nikkor 28-70mm, f2.8 on a Nikon D700. SB800 and SC-29 cable was used.

3. I'm not sure what you mean by "unrecoverable". When I open ACR, the faces are red (showing blown highlights). When I reduce the exposure in ACR, these blown areas revert to a normally appearing image.

When you direct a flash other than forward, it changes the geometry and, in Nikon, Matrix 3D metering cannot work correctly to modulate flash output according to distance information provided by the autofocus and lens.

I do believe that the 28-70mm zoom you have can provide the distance information, so that's not a problem.

I suggest the following starting settings in ACR:

Basic:
Start with Exposure at zero adjustment.
Start with Contrast at -20.
Use Brightness to adjust basic skin tones.
Use the Recovery, but not more than +30 adjustment.

Tone Curve: - "Point" tab - Pull down the Highlight dot until the brightest skin tones comply.

If these things work and if the skin tones look fairly natural then I suspect you are within a "normal" and correct exposure. If the skin tones will not correct at these settings then you need to add some minus flash exposure compensation to your other settings on the camera. As long as the results are consistent, it is nothing to worry about.

Another possible thing to try is using Center-Weighted or Spot metering modes, but then you might have to apply a positive flash exposure compensation if reading off of Caucasian faces.

Wil Davis

Mitchell wrote:

I'm a newbie with a bracket, but I'm pretty experienced with CLS. Why would you suggest I fire my flash wireless on my bracket? This makes no sense to me when I have an sc-29 cable. I'm not talking about a flash mounted on a separate light stand or pole. It's on a Stroboframe bracket. Who would use a wireless setup for this?? I do have an SU800, but it seems to me that my cable should provide me with ittl performance.

OK three points:

1) Mounting the SC-29 in the hot-shoe of the body prevents using the built-in pop-up flash thus preventing use of the body as Commander, or use of the pop-up flash for fill or catch-lights

2) Less clutter to carry around and fewer dangly things getting in the way etc.

3) I was under the impression that the SC-29 (which I've had for years, but have never used since discovering how to use wireless CLS), was for use on those bodies which didn't allow wireless


- Wil

Mitchell

Wil, you use your pop up flash as a controller when using a flash bracket like a stroboframe bracket?

I've never seen that done. Wouldn't the cable be a more reliable way to fire the flash on the bracket?

Wil Davis

Mitchell wrote:

Wil, you use your pop up flash as a controller when using a flash bracket like a stroboframe bracket?

Yes.

I've never seen that done. Wouldn't the cable be a more reliable way to fire the flash on the bracket?

Well, I've never had a problem with the pop-up being Commander. It works even when the bracket is flipped 180º and the sensor on the speedlight is facing away from the camera. If you don't need the fill/accents then set the Commander to "--".

Try it and see if it works for you

- Wil

Qarik

uhh..no need for the commander mode when you have a cord. That makes no sense.

Mitchell, I would suggest go straight matrix metering. You flash is partially bouncing and partially direct which maybe confusing the spot metering. I am 90% sure this will fix your exposure issue. If you want to explore WHY the over exposure is occuring..try moving the flash head so it is straight on direct or completely bounced while in spot meterign mode. I *think* the metering is getting confused becasue it is partially both right now. Btw was your flash diffused?

Wil Davis

Qarik wrote:

uhh..no need for the commander mode when you have a cord. That makes no sense.

…snip

Well, I would argue: "…no need for the cord when you have commander mode. That makes no sense."

After all, why keep a dog and bark yourself?



- Wil

Qarik

Wil Davis wrote:

Well, I would argue: "…no need for the cord when you have commander mode. That makes no sense."

After all, why keep a dog and bark yourself?



- Wil

Because the cord works guaranteed and the preflash may at time effect your exposure. With the commander you are not guaranteed to fire your flash every time (it happens). Also what if you have another photographer in the room? Your preflash may be effecting his or vice versa. *shrug*

Wil Davis

Qarik wrote:

…Also what if you have another photographer in the room? Your preflash may be effecting his or vice versa. *shrug*

Use a different† channel.



- Wil

† up to 4, if there are more than four photographers in the same room all using CLS wireless, then I might consider using an SC-29

jeffreaux2

Mitchell....this may apply to you....maybe...

One of my now and again assistants for weddings uses a bracket and cord for her flash/camera. Once, she experienced severe over exposure using this set up. I took her rig apart and mounted the flash in the shoe and ETTL worked fine. I reassembled it all and it worked fine. My conclusion was a faulty connection...somewhere.....something just not quite making up. I have also experienced identical scenario with a loosely attatched STE2 transmitter. This...of course is the behavior with Canon gear.

My belief is that when the flash isn't EXACTLY connected correctly it reverts to Manual exposure values. In other words...no ETTL...TTL or whatever Nikons equivilent is.

ziggy53

jeffreaux2 wrote:

Mitchell....this may apply to you....maybe...

One of my now and again assistants for weddings uses a bracket and cord for her flash/camera. Once, she experienced severe over exposure using this set up. I took her rig apart and mounted the flash in the shoe and ETTL worked fine. I reassembled it all and it worked fine. My conclusion was a faulty connection...somewhere.....something just not quite making up. I have also experienced identical scenario with a loosely attatched STE2 transmitter. This...of course is the behavior with Canon gear.

My belief is that when the flash isn't EXACTLY connected correctly it reverts to Manual exposure values. In other words...no ETTL...TTL or whatever Nikons equivilent is.

I've experienced that as well, but the flash reverted to full output, ... all the time and every time. Mitchell is just getting consistent apparent extra exposure.

Good thought however.

ziggy53

Mitch, this is just another hunch. Do you have another RAW converter to try?

Wil Davis

There was a thread a while ago somewhere on this board which referred to Russell MacDonald's blog.

The context was there being an anomaly between how Nikon documented the behaviour of their TTL/TTL-BL system, and how it actually worked.

I wonder if this link might be of any use to you?

HTH -
- Wil

PS: This one might have the answer to you original problem (see blog entry for March 8th, 2009 2:52 p.m.)

Scott_Quier

Mitch, just some random thoughts:

• Check that the cord is not damaged. My first thought would be to remove the cord from the flash and camera and do a continuity check of all the contacts. Simple job with any cheap (or expensive - if you don't have one, this might be a good excuse to get one ) multimeter.
  
  
• I almost always Expose to the Right, knowing that I'll be dialing it back down in post (and I ALWAYS shoot RAW).
  
  
• ACR showing the red blown highlights indicates you blew the red channel. If your camera allows for it (and I think most Nikon cameras do), it might be instructive to display the three-channel histogram rather than the luminosity histogram.
  
  
• Blinkies on the LCD are a good indication that you've blown all three channels but not, necessarily, any one channel. The corollary to that is, "Just because you don't have blinkies doesn't mean that you've not blown a channel." The image on the LCD will lie to you every time and is reliable only for checking composition of the shot. I would use only the histogram for checking exposure .... and even that's not a perfect solution but it's better than relying on the LCD image.
  
  
• There might not be anything wrong with your camera. I work under the assumption that the computer in the camera is stupid. It tries hard and usually gets close, but it's almost never perfect ... so I check the histogram, make adjustments and move one. That gets the job done.
  
  
• Once you've verified your equipment, it might be instructive to do a couple or three test shots using something like a Digital Calibration Target. This tool will create a nice three-spiked histogram when the target fills the frame and you have proper exposure - easy stuff. Anyway, something like this may help you come to better understand the way your flash works with your camera in the configuration you were using.

I don't know if any of this helped ... but I tried

time2smile

I have a D90 and D50 and two SC29 and two SC17, SB600. Ive shortened one SC17 for a bracket... I have not run into this with either setup.
Are you in BL mode?
Have you tried the FV lock instead of the preflash, it usually gives me better results. With either speedlight on or off camera.

The reason you do not wireless the flash on a bracket is because you can not guarantee line of sight when you rotate. Sure you may get lucky some of the time. But....

time2smile

This speaks of your issues, by the way how is it without the cord?

http://nikonclspracticalguide.blogspot.com/2008/01/ttl-flash-metering-system-not-ttl-bl.html

Wil Davis

time2smile wrote:

This speaks of your issues, by the way how is it without the cord?

http://nikonclspracticalguide.blogspot.com/2008/01/ttl-flash-metering-system-not-ttl-bl.html

…is there an echo in here? …echo in here …in here? …here? …? ? ? †

- Wil

† see post #20

time2smile

Wil Davis wrote:

…is there an echo in here? …echo in here …in here? …here? …? ? ? †

- Wil

† see post #20

My Bad, sorry I don't usually hit the underline links, and I cant seem to read the names either...

Mitchell

Wil Davis wrote:

I'm with Qarik; I think the black is messing things up. Also, why use a SC29 cord? I can't remember your main gear, but if it's Nikon, use wireless remote CLS; have the speedlite on the bracket as the main (group A), and use the built in flash on the camera as Commander and also as the fill (group ; meter for the background, and let the CLS sort out the flash, and tweak until good.

All the other stuff you post is just about perfect, so what gives? (I think we should be told! )



- Wil

Wil, I confess that I thought it wouldn't work. Actually, I wanted it to not work. But in the end, I put the SB800 on the bracket and fired it wirelessly from the pop up commander, and it worked like a charm. Fired my flash every time despite my efforts to get the flash to not "see" the commander.

More importantly, the ttl worked perfectly.

Here's one of my son SOOC. Exposure is right on the money!!

Wil Davis

Glad it worked out!



- Wil

Mitchell

Now I need to find a cold shoe for my bracket.

Wil Davis

If by "cold shoe" you mean one that won't short any of the contacts on the bottom of the flash, then just use a small piece cut from a polythene bag to act as a barrier over the base of the flash (sort of like a prophylactic). In fact, I think the flash-shoe on my Stroboframe is made of plastic (from what I remember).

- Wil

Edit: Just checked and the shoe on my Stroboframe is black anodized aluminium, and is stepped so that the electrical contacts on a mounted speed-light won't be shorted by the metal.

time2smile

Way to go Will, I'm going to try it myself over the weekend.

Ebay sells plenty of those little flash holders that have the screw to tighten on the side, usually sold with brackets. Of course I cant seem to find one when I look for it. Will search later, they have a cut out in them so they don't sort the contacts.

time2smile

Here one, there are much cheaper one out there.

http://cgi.ebay.com/Stroboframe-Hot-Shoe-Flash-to-Bracket-Mount-300-SHO-NEW_W0QQitemZ200415241357QQcmdZViewItemQQptZCamera_Flash_Accessories?hash=item2ea9ade48d