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Message: <blockquote data-quote="tdodd" data-source="post: 1194275" data-attributes="member: 55450">You've just explained to yourself why manual exposure is such a great tool. If you have a dark bird in the shot you want it to remain looking dark. You do not want autoexposure to decide for you that it would look much nicer at 18% grey. It's exactly the same with a light coloured bird. It should look light in the photo. Again, you don't want autoexposure to decide you're going to get an 18% grey bird whether you like it or not. What you really want in the scene is a grey bird (18% grey preferably) that you can use to set your exposure accurately. Then black birds will stay black, white birds will stay white and grey bird will stay grey. All other colours and shades will end up exactly where they belong. If you are not fortunate enough to have an 18% grey bird handy then you can use an 18% grey card and set the exposure from that. It will be just as effective as an 18% grey bird. Alternatively, meter off your palm (so long as it is in the same light as the birds) and set the exposure about +1 to +1 1/3 stops above the centre of the meter. Your palm does not tan and so can be used throughout the year as a fake grey card. Because your palm is paler (more reflective) than a real grey card you will need to dial the exposure in a bit over the zero to compensate. +1 to +1 1/3 will probably be about right, but you can test by trial and error exactly what works best for your skin and your camera. This is no different to shooting grooms in black tuxedos and brides in white dresses. The exposure should be set according to the incident light falling upon the subject, not the reflected light coming off it. Black tux, white dress, it doesn't matter - the exposure should be the same for both - you still want the skin tones and background to match from one photo to the next. Weddings togs use manual exposure all the time. But with in camera metering you have to make do with reflected light, and if the subject metered is anything other than 18% grey in luminosity then you will need to dial in some EC one way or the other to compensate. That all seems a bit like hard (guess)work to me. Manual keeps things really simple, once you have the exposure set correctly. Metering off grass is perfect, if the grass and the bird(s) are both enjoying the same lighting. If the grass is in bright sunshine and the birds are flying in the shadows of trees (or vice versa) then you'll have to find something else to meter off. If the bird is in shade then meter off some grass in the shade. If the bird is lit by open sky or direct sunlight then find some grass that is lit the same way. Grass does differ in tone, so you may have to manually choose to "overexpose" a bit or "underexpose" a bit. That's fair enough. If you're shoting in a snow scene you'll have to "overexpose" quite a lot, because all that bright white snow will cause the camera's metering to want to dim it down to 18% grey. Of course, you actually want the snow to be captured as brilliant (but not overexposed!) white. If you shoot with autoexposure you will likely need to dial in a couple of stops of +EC to tell the camera you want the whites kept white. Apart from the tone of the bird altering, which should not change your exposure settings in any way, the exact same thing goes for the background, which will most likely dominate the meter reading more than the bird in any case. If a bird is flying level with the top of the treeline, sometimes against a blue sky, sometimes against the dark trees, you don't want the exposure to keep bobbing up and down with the bird. If the bird is lit constantly then the exposure for the bird should not change at all, regardless of what the background is doing. Suppose the bird is flying over ground and heading for a lake, with bright specular reflections all over it. Should the exposure for the bird suddenly change simply because we have a new, brighter background? I don't believe so. The bird may get a bit of extra light underneath, but the top of the bird, where the light originates from, will be getting no more and no less light than before. You want to fix the exposure for the bird. Nothing else. You'll only come unstuck with manual exposure if the light changes (clouds rolling in and out again) or the bird is ducking and diving in and out of shade. You can then choose whether to adjust your manual settings to suit the new conditions or take your chances with auto exposure of some kind, and manual exposure compensation. If all else fails, and your are struggling with metering, for whatever reason, try the good old manual fallback of the SUNNY 16 RULE. It's all explained here - <a href="http://medfmt.8k.com/mf/sunny.html" target="_blank">http://medfmt.8k.com/mf/sunny.html</a>. You can, of course trade off shutter speed, aperture and ISO to maintain the correct overall exposure and get the shutter speed you need to control motion and the aperture you need to conrol DOF. So, for example, in sunny conditions, instead of f/16, 100 ISO, 1/100 you might choose f/8, 400 ISO, 1/1600 for the same exposure. I've attached six images I just shot, in the sunshine, to demonstrate the differing results from different metering/exposure approaches. I left the camera on a tripod for each shot, to replicate each composition perfectly. Top left - using the sunny 16 rule, this was shot at f/8, 400 ISO, 1/1600. There is almost nothing in the picture that is pure white or highly reflective. Using DPP to assess how much headroom I have before clipping I'd say I had 2/3 stop of spare headroom. That would be my safe margin to hold details for anything bright white, like a white bird, for example. If I'd stuck a sheet of white A4 in the scene it should have been near the top of the scale but, hopefully, unclipped. Top centre - Av mode, pattern/evaluative metering. Still at f/8 and 400 ISO, the camera picked 1/1000 as my shutter speed. Spookily, the exposure is bang on and exposed beautifully to the right (I only shoot raw). If I increase the exposure by even 1/6 stop in DPP I see highlights get blown on some window frame in the distance. Top right - AV mode, partial metering. Still at f/8 and 400 ISO, the camera picked 1/2000 as my shutter speed. Clearly the brightness of the wall of the house is pushing my exposure down a bit. The picture looks underexposed. Sure enough, I can push the exposure up by a full stop in DPP before my highlight clipping indicators appear. Bottom left - Av mode, spot metering. At f/8 and 400 ISO once more, the camera has picked 1/3200 as my shutter speed. The spot meter was totally over the bightest part of the wall. Now the image is severely underexposed. In DPP I can push it 1.5 stops brighter to see just the barest hint of clipping. This is clearly down to bad metering technique, but it shows how susceptible the meter is to being pointed at the wrong thing. Tracking a bird with spot metering?.... a tough chalenge indeed. Bottom centre - Av mode, CWA metering. At f/8 and 400 ISO, the camera picked 1/1250 as the shutter speed. That's a third of a stop brighter than my sunny 16 manual exposure. Pretty much perfect for this scene - I can only add 1/6 stop in DPP before getting the clipping warning. Bottom right - Back to manual mode with the sunny 16 exposure setting. I used partial metering to meter the centre of my palm to see what the meter thought of it. The meter indicated that I was overexposing by between 1 stop and 1 1/3 stops. We know that the sunny 16 exposure does not overexpose so my palm was "lying" when it told the camera it was overexposed. I basically now know that my palm is about 1 1/3 stops brighter than 18% grey in the eyes of my camera. That means that if ever I need to set a manual exposure but have nothing reliable to meter off, all I need to do is meter my palm in the same light conditions as the scene/subject and make sure the needle is pointing at +1 to +1 1/3 stops overexposed.</blockquote>

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