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Fresno, TX 77455-1505
ph: 281-778-1486
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April 2016 - This month's newsletter focuses on photographing birds in flight using manual mode settings and discusses when to use manual versus aperture priority. It includes images of Blue-footed Boobies from the Galapagos.
Blue-footed Booby photographed January 2016, San Cristobal Island, Galapagos. Canon 5D3 500F4, 1/6400 F5.6, iso 800, Av mode, evaluative metering at 0. I didn't adjust the exposure, brightness, contrast etc of the shots in this newsletter to show exactly how the exposure came out of the camera. This shot is obviously not a very good shot unless I was going for a silhouette. The image is underexposed by a couple of stops. With the very light sky background the camera overcompensated as it's trying to turn the image into a medium tone, thereby making everything way too dark. I shoot in aperture priority most of the time as I find it's the fastest way to change settings and get my shot the vast majority of the time. In this case I may have been shooting something on the ground, saw the booby and just started shooting without adjusting my settings. But the resulting few images are a good example of why if you are shooting birds in flight in consistent light, it's typically better to shoot in manual mode.
Blue-footed Booby, Canon 5D3 500F4 1/4000 F6.3, iso 800, Av mode, evaluative metering at 0. This shot is from the same diving sequence. The exposure is a little better here but still quite dark. Here with the pattern metering (matrix for Nikon users) the metering is picking up some of the green backgroound so the bird is not quite so dark. But it's still underexposed by a full stop or more.
Blue-footed Booby, Canon 5D3 500F4 1/1000 F5.6, iso 800, Av mode, evaluative metering at 0. In this image the background is only the green hillside so the evaluative exposure is much lighter as it's not trying to turn something very light into a medium tone. In fact you could argue that this is a touch too bright. So going from the first image at 1/6400 to this image at 1/1000 we have a change of 2.7 stops of exposure, a huge change. One way to compensate for changes in the background when shooting in aperture priority is to dial in positive or negative exposure compensation but with a bird moving very fast like this you don't have time to dial in a large amount of compensation like you would have needed here. Also note that as the bird gets against a darker background you lose shutter speed, 1/1000 is not quite fast enough to stop this speeding bullet as it dives. If on the other hand I had dialed in +2.0 positive exposure compensation to get the booby light enough against that bright sky, it would have been way overexposed when it passed through the medium tone green background and the shutter speed would have been very slow, the image would have been a blur. So how do we handle this situation? The best way if the light is consistent is to photograph in manual mode.
Blue-footed Booby photographed January 2016, San Cristobal Island, Galapagos. Canon 5D3 500F4 1/2000 F5.6, iso 800, manual mode. The light brightened a little bit after the previous image. We were in bright overcast conditions and I took a meter reading off of the light gray sky. I figured I needed to add a little bit more than 1 stop of light to the evaluative metering reading that the camera was giving. So the camera metered this at 1/5000, adding 1.3 stops of light got me to 1/2000 at F5.6, iso 800 so that is what I set my manual exposure to. Note that if you weren't getting a fast enough shutter speed at the correct exposure then you would want to increase your iso if you kept your aperture setting steady. Honestly I think 1/2000 is a little bit slow for this shot and if I did it over I probably would have gone to 1/2500 with an iso of 1000.
Blue-footed Booby, Canon 5D3 500F4 1/2000 F5.6, iso 800, manual exposure. Now with the manual exposure set the shutter speed doesn't change as the bird flies from the bright sky area into the medium toned green background and as long as the light is consistent than you get the same exposure on the bird in both frames. Now if the light had been for example sunny on the bright sky and the area in front of this green hillside covered in shade you wouldn't want to shoot manual because the light wouldn't be consistent from one shot to the next.
Blue-footed Booby, Canon 5D3 500F4 1/2000 F5.6, iso 800, manual exposure. This is one of the take off shots after the booby had hit the water from the previous two frames shown. The lighting that is hitting the water was the same and the exposure on the bird is similar. Another way to have metered this series would be to take an evaluative reading off of the bright water, I find this is pretty close to a medium tone usually so you wouldn't have to add the 1.3 stops of light to whatever the camera was reading (Here I think the camera would have read this about 1/2000 at F5.6 and iso 800). Of course you want to check your histogram after a series to see how your manual settings are working out.
Blue-footed Booby, Canon 5D3 500F4 1/2000 F5.6 iso 800, manual mode. This image was taken about 20 minutes after the previous 3 images. The solitary booby landed on a rock quite near us and we were able to photograph it sitting and preening for quite a while. The lighting quality hadn't changed from the previous 3 shots so the manual exposure that I had set still worked well. It was really nice to have this bird up close, it was the same spot where I had photographed a pair of Blue-footed Boobies up close in good light the previous year in the late afternoon. We had to wait an hour or so before this one stopped fishing and landed on his preening perch. I think most of the participants thought it wouldn't happen when the bird was fishing so it was a good lesson in patience and a reminder that birds and animals often repeat behaviors and return to their favorite spots at certain times of day.
Blue-footed Booby, San Cristobal Island, Galapagos. Canon 5D3 500F4 1/2000 F7.1, iso 800, manual exposure. This image was taken about 5 minutes after the previous image. During that period of time the sun had come out from behind some clounds and lit up the booby. I didn't want to blow out the whites in this brighter light so I decreased the exposure by stopping down from F5.6 to F7.1. When shooting in manual mode you always need to pay attention to the lighting and if it changes adjust your exposure, checking your histogram after doing so. So if you are photographing birds in flight in consistent light, especially against changing backgrounds shooting in manual mode is the way to go.
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PO Box 1505
Fresno, TX 77455-1505
ph: 281-778-1486
nchappel