12,800 ISO noise looks different with flash

Dave Black was speaking at a seminar about using his Nikon Speedlight SB900 flashes instead of his Studio heads to light a basketball court and an ice rink.

I was on the edge of my seat absorbing what he was talking about.  I didn't go out and buy more SB900 flashes and use them instead of my strobes for one reason, clients were not paying for sports coverage as in years past.

But what I was listening to was some of the reasons it was working for Dave Black.

First, by just having his strobes just a little over ambient light level he was able to get better color and avoid the problem with sodium vapor lights. Dynamic range under flash is the greatest light spectrum. Dave Black was shooting his flash just enough over the ambient to affect the color and help shift it to the 5000º Kelvin range.

Sodium vapor lights flicker and when you are shooting above 1/100 shutter speed you can get color shifts to all or just a band through a photo.

Another thing of shooting with the Nikon Speedlights was the ability to shoot at just about any shutter speed.  So in ice hockey Dave was able to freeze the puck by shooting at 1/2000.  The basketball was sharper as well for his basketball.

Available Light only (Nikon D3S, ISO 12,800, f/5.6, 1/40, 28-300mm)

I began to experiment with using strobes with high ISO since then and found some things that it benefits other than just for sports.

I shot here the same photo three different ways. I have the statue lit by window light.  I shot it with nothing but the window light and any bounce back fill is just from the room.  I shot it at ISO 12,800.

As you can see the highlights look good and it is in the shadows that you will notice more noise. 

Fill Flash set -3.0 (Nikon D3S, ISO 12,800, f/5.6, 1/30, 28-300mm)

By putting my SB900 with the dome on the camera and just bounce flashing I was able to get a little different results.  I underexposed the flash by -3 stops.  I did this by adjusting the setting on the back of the flash.

As you can see the shadows are now not totally black as in the first photo.

Then I shot also one more photo with the flash at a normal setting which gave me a lot more light.  This wipes out the shadow detail completely.  However, since I am using it in rear sync mode it was still complementing the window light and not over powering it.

Fill Flash normal setting (Nikon D3S, ISO 12,800, f/5.6, 1/20, 28-300mm)

You really need to zoom in to see some of the noise issues with each photo.The place the noise shows up the most is in the green in the background.  You can see a lot of noise the more it is in the shadow.

Available Light only (Nikon D3S, ISO 12,800, f/5.6, 1/40, 28-300mm)

Fill Flash set -3.0 (Nikon D3S, ISO 12,800, f/5.6, 1/30, 28-300mm)

As you add more fill light (-3 stops) the noise diminishes a great deal.

Fill Flash normal setting (Nikon D3S, ISO 12,800, f/5.6, 1/20, 28-300mm)

What I noticed is when you add Nikon Speedlights to high ISO photos like these shot at 12,800 ISO noise diminishes. 

Less Flash output at High ISO

When you raise the ISO setting on your camera, every stop you raise it the flash only needs to put out half as much light as it did.  If you leave a Nikon D3S on auto ISO and the lowest ISO is 200, then the minute you put on your flash and turn it on the ISO will drop to 200.

You will need to manually set your ISO to the high ISO you desire.  Here I chose ISO 12,800.

The amount of light needed by the flash to put out at this setting is 7 stops less than at 200.  This also means your flash can increase it's distance of throw by 7 times as well.  This means if your flash only would work at 10 feet at f/4 and ISO 200 you can now get f/4 at 640 feet away at ISO 12,800.

Color Temperature affects noise

I have found from my experience that whenever you shoot with flash you have the greatest dynamic range.  Therefore the noise is less with flash than say incandescent, fluorescent or sodium vapor light. 

Slow and Rear Shutter setting 

On the Nikon system, when you have the flash balance with the existing light then the flash only needs to do a little work, because it is complementing the light not being the primary light.

Why do I shoot with Nikon?

The Canon speedlight system is similar to the Nikon TTL Speedlight system.  You can use Slow and Rear Shutter settings, BUT the higher you go with the shutter speed the flash gets darker and not as consistent as the Nikon system.

My point is if you want to shoot with shutter speeds of 1/8000 with your speedlights, then you better have the Nikon.