Help Shooting in High School gym!

[ElCapitan]

I have recently started photographing basketball games at my old High School. I am using a Canon 5D MkII, Canon 70-200 f/2.8L II, and a monopod. The settings I am using are ISO 4000, 1/640 shutter speed, f/2.8 and a custom WB. Oh, and I am shooting in RAW.

The problem I am running into is that for some reason I can shoot 3 consecutive shots of a person standing still, and the lighting and WB may look different for each of them. Nobody else is shooting flash in the gym. The lights don't appear to be changing. So what is causing this? One shot may have very pale skin and look bright, while the other may have redder skin and look a little bit darker. I know it isn't my camera as I don't have this problem at any other time. Just in the gym. Is this common and just something you have to deal with?

The problem is going through RAW on every single shot. Rather than going in and giving every image the same WB and roughly the same exposure and color saturation and luminance settings, I have to go through most of them individually, and even then I have to go through most photos as PSDs in PS and work on the color balance and levels.

[autofocus]

...using flash?

[ElCapitan]

Originally Posted by autofocus

...using flash?

I wasn't using a flash, and I didn't notice anyone in the stands using a flash. Everyone I noticed taking pictures were not using flash, though it could have been they only used flash when I was focused on the player, though i never noticed any flashes while looking through the viewfinder.

[ravncat]

Fluorescent lights usually flicker at about double the frequency of the electrical current used, so an entire cycle will take between 1/100 and 1/120 second. During the cycles the light's intensity and color temperature tend to change. Since you're using a shutter speed faster than 1/100th, you are probably seeing these phenomena.

For sports photography indoors you may have to consider flash options. Very short exposures (down to 1/4000th or so) can be had with HSS flashes. If you're shooting raw you can try to compensate, but that's going to be tricky during the color transition.

the lights are essentially blinking different colors during your exposures. More annoying is that different fluorescent lights are usually on different circuits, so they can be out of phase by 180 degrees, and if they are not installed with the same temperature color bulbs in all the fixtures color differences in a cycle will be even greater.

This is made even worse by the rolling shutter above a given speed (usually around 1/200. This means that only a portion of the image sensor is exposed to the scene at any moment and if the light changes during the exposure, the color temperature change will only affect a portion of the image sensor.

You have a few options:

* Decrease the speed so you get at least one full cycle of light (1/60th in the US, 1/50th elsewhere) per exposure
* Overpower the local lights with flash (which also has limitations above the 1/200 sync exposure, but high end flashes can take care of this for you)
* Take a lot of raw photos and note areas where color references can be used to white balance the photos in post-processing for those shots where the color doesn't change mid-exposure

[autofocus]

Just thought that rapid firing shots using flash could have caused the problem..(cycles flash to quickly not allowing full charge between shots)...but that's not your problem...and an odd one at that

[autofocus]

Originally Posted by ravncat

Fluorescent lights usually flicker at about double the frequency of the electrical current used, so an entire cycle will take between 1/100 and 1/120 second. During the cycles the light's intensity and color temperature tend to change. Since you're using a shutter speed faster than 1/100th, you are probably seeing these phenomena.

For sports photography indoors you may have to consider flash options. Very short exposures (down to 1/4000th or so) can be had with HSS flashes. If you're shooting raw you can try to compensate, but that's going to be tricky during the color transition.

the lights are essentially blinking different colors during your exposures. More annoying is that different fluorescent lights are usually on different circuits, so they can be out of phase by 180 degrees, and if they are not installed with the same temperature color bulbs in all the fixtures color differences in a cycle will be even greater.

This is made even worse by the rolling shutter above a given speed (usually around 1/200. This means that only a portion of the image sensor is exposed to the scene at any moment and if the light changes during the exposure, the color temperature change will only affect a portion of the image sensor.

You have a few options:

* Decrease the speed so you get at least one full cycle of light (1/60th in the US, 1/50th elsewhere) per exposure
* Overpower the local lights with flash (which also has limitations above the 1/200 sync exposure, but high end flashes can take care of this for you)
* Take a lot of raw photos and note areas where color references can be used to white balance the photos in post-processing for those shots where the color doesn't change mid-exposure

Aha..an answer, thanks for the scientific explanation Ravncat

[ElCapitan]

That does explain a lot. That was my initial guess, though I had no idea of the exact reason behind it. Well that is a shame, as I will not be able to use a flash at the HS games.

After my first round of rejects, I have 404 photos. I'd like to knock it down down to 250-300 but it's tough to determine rejects after a certain point.

[lputman]

Consider shooting a series to use WB from post. For instance if you are using some type of gray card or other tool, shoot it multiple times so you catch the cycling lights and you can then match up in post for WB. Otherwise, you'd have to use your own lighting to overcome the cycling.

[zona5101]

Lori has a good idea. You could then create a series of presets in Lightroom for each lighting condition then use a single click to fix the wb in post.

[GTAltman]

Originally Posted by lputman

Consider shooting a series to use WB from post. For instance if you are using some type of gray card or other tool, shoot it multiple times so you catch the cycling lights and you can then match up in post for WB. Otherwise, you'd have to use your own lighting to overcome the cycling.

Lori,

How many shots would be necessary? 5? 10?

Thanks.
Gary