Strobes BB - 2nd Attempt

MDalby · February 5, 2011

Well, I made some adjustments and the shadows are reduced and the lighting isn't as harsh BUT I got a new set of problems.

I tried a different lens and shot with my 70-200mm f2.8 rather than my 50 mm 1.4 prime.

In my last attempt, I was getting very clear images but lots of shadows.

Tonights game was at another gym. The lighting was not as nice as our home gym. I clamped the strobes much higher in the gym and there was improvement in the shadows. but I am getting blurring/ghosts in my images. It doesn't look like the flash was freezing the motion like it did the prior attempt.

Image 1A:

Image 1B:

Image 1Exif:

Image 2A:

Image 2B:

Any tips are appreciated. I feel things took a couple of steps back tonight.

Zerodog · February 5, 2011

The blur is from your shutter speed. Can you use high speed sync with your flash setup?

MDalby · February 5, 2011

I used the same shutter speed in my 2nd attempts as I did in my 1st shots and I had no blur in the 1st shots. I think 1/250 is my max shutter speed. I also understood that the high speed sync wouldn't really improve things.

Thanks

MDalby · February 5, 2011

Zerodog,

I found this post by Sean that I think explains the sync speed and flashes best.

http://www.dgrin.com/showthread.php?p=1468304&highlight=trigger#post1468304

donek wrote: »

shot with ebay triggers and 4 bounced speedlights (3 SB-800, 1 SB-28).

This topic has been covered many times. High speed sync is completely unnecessary. Expensive triggers aren't necessary unless you are in a very large arena (probably not even then) or shooting where many other photographers are shooting at the same time...

The simplest explanation of why high speed sync isn't required is something everyone here has likely experienced. Think of your flash as a strobe similar to the one you see on dance floors. Your eyes are open far longer than any shutter and for some reason the dancers appear to be stopping. Your flashes burst of light is far shorter than your shutter speed when not set to high speed sync. As long as the camera interprets the ambient light as very dark (2 stops underexposed) and your flash power is adequate to compensate for your 2 stop underexposure, the flash will stop the action even at a shutter speed of 1/60th. Using high sync speed on your flash actually lengthens the duration of your flashes light burst in order to compensate for the time it takes to open and close the louvers in your camera. As a result you get far less power from the flash, requiring more battery power and longer recycle times.

So... It looks like my issue is that, "the camera [DID NOT] interpret the ambient light as very dark (2 stops underexposed) and your flash power is adequate to compensate for your 2 stop underexposure, the flash will stop the action even at a shutter speed."

Again, it looks like I just don't have my settings correct. I obviously don't understand the way to determine ambient light and the correct stops to go back to have the correct fill from the flashes. I need someone to get out the big crayons and the wide lined paper and spell it out for me.

AMBIENT LIGHT
What I did is I switched my mode to Aperture Priority to get a meter reading without any flash. If I remember correctly this is what the settings were during my test shots: ISO 1250, f/2.8, 1/320, focal length 78mm.

CAMERA SETTINGS W/FLASH
I then backed down my SS to what I think is my max sync speed. The camera settings with the flashes were at ISO to 1250, f/2.8, 1/250, f 70mm.

FLASH SETTINGS
My flash settings were at 1/8 power, ISO 1250, f/2.8, 70mm, No Standby, Zoom off.

What should I have done? I changed my lens to my 70-200mm f2.8. What aperture do you shoot at with your 200 2.8 for basketball? Do you shoot at f/3.5 or 4?

Thoughts?

jbakerphoto · February 5, 2011

Your letting to much ambient light in. You want the flash to stop the action. It cannot do this if you are using it as fill. So I would try dropping the iso to like 800.

Dreadnote · February 5, 2011

This sounds like the same problem I am trying to work out. I am just a rookie but this is what I tried:

Set meter to matrix metering.
Pick max shutter sync speed.
Aperture at 2.8 unless you think you can get away with a smaller one.
Dial ISO up or down until the meter indicates 2-3 stops below ambient.

At this point, if I understand things correctly, the only way to change the ambient to flash ratio (w/ shutter at max sync and aperture wide open) is to lower your ISO and increase power to your flash. So I think in your case I'd bump the flashes to 1/4 power and drop the ISO until you are balanced at 2-3 stops under ambient. Hobby over at strobist.com http://strobist.blogspot.com/2006/04/on-assignment-prep-basketball.html in his on-assignment piece in low lit gyms stated that he used 1/2 power:

The flashes are going to be set on manual at about half power. If the lights are typical sodium vapors or florescent (it'll almost certainly be one of the two) set your camera on florescent and green your flashes. It'll get you pretty close in either case. And besides, the ambient is only acting as fill.

Set the flashes to the 50mm zoom setting. You want a balance of coverage angle and ability to throw the light. You may be able to get away with a 70mm flash zoom setting for more efficiency. But you will have to experiment.

Aim the lights to a point about ten feet in the air above the top of the key.
The strobes should give you a pretty honest f/2.8 at your highest synch speed at ASA 640. If they are hot, turn down your ASA. If dark, vice versa.

Of course I'm still working this out for myself, so here is my attempt at it. It will no doubt involve a lot less walking back and forth once Pocket Wizard really ships the miniTT5-nikon and miniTT1-nikon that they supposedly already shipped.

:

MDalby · February 5, 2011

OK, I went into my home gym today and I think with the readings I am getting I can shoot with the following settings on Tuesday night.

I am planning on using my 70-200 f/2.8 lens
ISO either 320 or 400
f/3.2 or 3.5
1/250

I think this will freeze the motion that I was missing last night.

MD

Toshido · February 6, 2011

MDalby wrote: »

Zerodog,

I found this post by Sean that I think explains the sync speed and flashes best.

http://www.dgrin.com/showthread.php?p=1468304&highlight=trigger#post1468304

So... It looks like my issue is that, "the camera [DID NOT] interpret the ambient light as very dark (2 stops underexposed) and your flash power is adequate to compensate for your 2 stop underexposure, the flash will stop the action even at a shutter speed."

Again, it looks like I just don't have my settings correct. I obviously don't understand the way to determine ambient light and the correct stops to go back to have the correct fill from the flashes. I need someone to get out the big crayons and the wide lined paper and spell it out for me.

AMBIENT LIGHT
What I did is I switched my mode to Aperture Priority to get a meter reading without any flash. If I remember correctly this is what the settings were during my test shots: ISO 1250, f/2.8, 1/320, focal length 78mm.

CAMERA SETTINGS W/FLASH
I then backed down my SS to what I think is my max sync speed. The camera settings with the flashes were at ISO to 1250, f/2.8, 1/250, f 70mm.

FLASH SETTINGS
My flash settings were at 1/8 power, ISO 1250, f/2.8, 70mm, No Standby, Zoom off.

What should I have done? I changed my lens to my 70-200mm f2.8. What aperture do you shoot at with your 200 2.8 for basketball? Do you shoot at f/3.5 or 4?

Thoughts?

Sounds like to me that you want to set the camera to underexpose by 2 stops with ambient light and light the subject with just the flashes.

All other things equal you slowed the SS to 1/250 which actually overexposed the ambient by 1/3 stop. So you were going in the wrong direction with your exposure.

So if I was trying what you are doing I would have tried shooting at 1/200 (I don't trust my cheap triggers at 1/250) which would overexpose my ambient by 2/3 stops. Drop my ISO to 400 which would drop exposure 1 1/3 stops leaving me underexposed by 2/3 stops. Then stop down the lens to f/4 for another stop of underexposure to ambient for a total of 1 2/3 stops underexposed.
Of course assuming you have enough flash power to illuminate at ISO 400 F/4.

Now I am still learning flashes and manual exposure with them so I may be WAY off in my thinking and if so hopefully someone will correct me.

Also using HSS, if available to you in this case would be more about killing ambient light then stopping motion.

Dreadnote · February 6, 2011

So if I was trying what you are doing I would have tried shooting at 1/200 (I don't trust my cheap triggers at 1/250) which would overexpose my ambient by 2/3 stops. Drop my ISO to 400 which would drop exposure 1 1/3 stops leaving me underexposed by 2/3 stops. Then stop down the lens to f/4 for another stop of underexposure to ambient for a total of 1 2/3 stops underexposed.

Based on what I've seen that is not underexposing the ambient enough. You want to underexpose by two or three full stops (ie. bring ISO from 1600 to 400) not by 2/3 or 1 2/3 stops.

My home gym has ambient levels at ISO 3200, f2.8, 1/320. The pic I posted above was shot at ISO 800, f2.8, 1/320 with the flash dialed in appropriately.

Toshido · February 6, 2011

Dreadnote wrote: »

Based on what I've seen that is not underexposing the ambient enough. You want to underexpose by two or three full stops (ie. bring ISO from 1600 to 400) not by 2/3 or 1 2/3 stops.

My home gym has ambient levels at ISO 3200, f2.8, 1/320. The pic I posted above was shot at ISO 800, f2.8, 1/320 with the flash dialed in appropriately.

But good my math was right. 1 2/3 stops under is still better then 1/3 over...

Strobes BB - 2nd Attempt

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