I’m trying to shoot continuous movement indoor im Sport Mode. The room is well lit but the photos come out with drastically varying lighting so some photos in the sequence are well lit while others are very dark. Any suggestions of how to fix this?
Most probably, this is due to the lighting and its continuous pulses.
The problem images [...] have usually been captured under fluorescent or gym/arena lighting and a short exposure was often used. Shooting action sports with a fast frame rate is most frequently the source – most of these images will appear properly exposed but an intermittent dark image glaringly appears.
The cause of this problem is usually not the camera, but the light themselves. [...] The more intermittent the light output, the more likely that your very short exposure may be timed to coincide with that light's low cycle. And the result is a dark image.
A great option is to strobe the venue. Securely mount [...] strobe lights in the venue's ceiling and fire them remotely [...]. This lighting technique promises the best-possible full-spectrum lighting.
The option that many [...] take is to simply deal with the conditions. Shoot in RAW and select an exposure that does not result in blown highlights when the lights are under full output.
The arguably best solution, however, is to get a fairly recent camera that features an anti-ficker-mode (such as the EOS 7D Mark II):
When enabled [...], Flicker Mode adjusts the shutter release timing very slightly so that the dim cycle of the lighting is avoided. In single shot mode, the shutter release lag time is matched to the light flicker cycle's maximum output. In continuous shooting mode, the shutter lag and the frame rate are both altered for peak light output capture. In my tests [...], the frame rate was reduced by 1-2 fps and shutter lag can be affected, making the camera feel slightly less responsive.
Any suggestions of how to fix this?
- Replace the lighting with a type that does not flicker at the rate of the cycle of the alternating current powering the lights.
- Use shutter times longer than one-half full cycle of the flickering lights. For countries where alternating current is 50Hz, that would be 1/100 second. For countries with 60Hz AC, that would be 1/120 second.
- Use a camera that has a "flicker reduction" feature that syncs the release of the shutter with the peak in the cycle of the lights' oscillation.
The variability you are seeing in your photos is due to the way many types of lighting convert alternating current into light. Although they look constant and steady state to our eyes, in reality they are flickering with the oscillations in the alternating current supplying them with electricity.
When shooting under any kind of flickering lighting, including fluorescent, each frame can have different brightness and color as the lights get brighter and dimmer due to the alternating current powering them. They tend to be bluer and fuller spectrum when at the brightest peak and browner and much more limited spectrum when at the dimmest part of the cycle. If you are using a shutter time shorter than half of the frequency of the current powering the lights, the color and brightness will change from the top to the bottom of the frame as the slit between the curtains of your focal plane shutter transits across the imaging sensor. The shorter the shutter time, and thus the narrower the slit between the first and second shutter curtains, the more pronounced this effect will be from one side of the frame to the other. Even with an electronic shutter you will see the effect with CMOS sensors, which scan across a sensor sequentially.
There are a few DSLRs now on the market that use the light meter to detect the timing of flickering lights and time the shutter to open when the lights are peaking. This allows the photo to capture the image as the light is at both its brightest and fullest spectrum. Since the shutter opens at the brightest point in the cycle, it allows shorter shutter times for the same ISO and aperture settings. This can be quite an advantage when shooting sports under flickering lights. It also allows more uniformity from one frame to the next which simplifies the post processing workload.
The accepted answer to Lots of noise in my hockey pictures. What am I doing wrong? gives a few tips on how to shoot, and process, sports taken under such flickering lighting.
It's not sports or indoors, but Should I use a 24-105 or a 70-200 lens for photographing a high school marching band? covers basically the same thing: shooting action under relatively dim flickering lighting. The accepted answer delves into a lot besides just lens selection.
For more related reading here at Photography SE, please see:
Why are my football action shots blurry?
How to edit photos shot in fluorescent light
Is there a low light picture quality difference between 50mm 1.8 G and 85mm 1.8 G Nikon?
This answer to Color matching Product
I had the same issue when shooting my son's gymnastics meets and my daughter's soccer matches (outdoors, under lights). I learned (here, I believe) that I should turn off Auto White Balance, and instead select a fluorescent or tungsten balance (or use a meter to determine & enter the value in K).
While it still left some dark images on occasion (especially on high school soccer pitches which were horribly lit), it fixed most of the issues I had and it also fixed the weird color shifts that happened from frame to frame.