I have been sent a PM and in a nutshell it asks why, when we have the same camera, for birds in flight shots do my images look clean and their images exhibit unacceptable noise at high ISO. There are four reasons I can think of to answer here, rather than respond by PM:
I shoot in RAW, as do the majority of you, but I have found that although it is helpful to manipulate the shooting parameters with your RAW converter, dragging the sliders too much degrades the image and introduces quite a lot of noise. Therefore to maximize image quality, you need to nail the exposure in camera.
The example I was given was for a bird in flight, sometimes with landscape as the background and sometimes sky and this was continuously changing, so Auto ISO was chosen. I haven’t had much luck with auto ISO – yes it keeps your chosen shutter and aperture by altering the ISO to suit, but by doing this it exposes for the overall brightness of the scene, rather than just the subject. The subject will come out OK if the background is landscape, but rather dark against a bright sky. You may well get better results on spot metering, but that is rather a small target to continuously keep tracked by the spot meter and in my experience, being slightly off target, you can end up metering for the sky.
I use manual exposure, metering for an 18% grey scale, skin tones, or grass, whichever is convenient. I will set the shutter speed (usually between 1/1,000sec to 1/2,000sec) then set the aperture (on my f4 lens between f5.6 to f8) then dial in the ISO to give me those settings. With luck ISO400, but in practice anywhere up to ISO3,200 and sometimes even ISO6,400. Because I have set the exposure for 18%, skin, or grass, that should give me a good exposure for the bird, regardless of whether it is against the landscape or the sky. After all, it is the bird that I want to nail the exposure for and if the sky burns out a little, so be it. The downside of this method is that I have only set the exposure for those lighting conditions and if the light intensity changes, I need to be aware of it and alter the manual exposure to suit. A bit scary when you first use it, but after a while you don’t need to re-meter, just flick the ISO up or down to suit.
Post processing I use DPP. I have used other products, but DPP is relatively quick, fairly simple and developed exclusively for the Canon RAW file, so it doesn’t need to be a compromise to deal with numerous camera makes. Nothing too radical here though, just do the minimum necessary and don’t work those sliders too much. The more you use them, the more noise you introduce.
Next is the final polish in Photoshop, or whatever editing program you use. If you have used high ISO’s of maybe 3200, or 6400, there will inevitably be some noise. You will have minimized the amount by nailing the exposure and limiting any alterations in your RAW editing, but there will still be some, especially noticeable in flat areas of the same colour, such as the sky. It will probably not be all that noticeable in the subject bird, because that generally has a lot of detail, which masks the effects of digital noise. However, if you apply noise reduction globally to the whole shot, it has the unfortunate effect of softening everything, including the bird. So, I make a selection of the subject and make a new layer of it, then revert to the background layer and apply noise reduction to that. Again, not too much, as little as you can get away with. If you need more, I often try an alternative of adding some Gaussian Blur, but just 0.5 to 1.0 pixel. If you overdo the burr, it can give a Moire effect, which is quite unsightly. Noise reduction will have slightly softened the sky/background areas, but as the subject bird is on a layer above, it is still sharp and carries a lot of detail.
There are three elements to what we refer to as noise – Luminance, Chrominance and JPEG artifacts. The artifacts are a result of over processing, are the most unsightly and need to be avoided. Chrominence is the unusual coloured pixels, usually magenta and cyan in light areas and green and red in shadow areas. Luminence is more described as a grain effect and tends to be more acceptable, as long as it is not combined with obvious Chrominance. I use a little correction for Luminance, a bit more for Chrominance and avoid any previous over processing to keep artifacts at bay. You will need to experiment with these settings to see what is acceptable for you.
If you need to add a “little” sharpening to the bird on the top layer, no problem, but again, don’t overdo it. Size, crop, flatten image and output in your normal format and you should end up with some clean, quality images.
I strive to spend as much time taking the images and as little time playing with them on the computer, but sometimes conditions are against you and you have to use the tools available to you to get it right. The secret is to nail the exposure and from then on, do as little as you dare, rather than as much as you can.
Hope that helps and I welcome your thoughts and suggestions.
- The gremlins are in my system and I am unable to answer PM’s at the moment.
- There is no short easy answer and I need to go into more detail than a PM warrants.
- There may be other members that could benefit from my thoughts.
- There may well be better ways than mine and I could benefit from other member’s experience.
I shoot in RAW, as do the majority of you, but I have found that although it is helpful to manipulate the shooting parameters with your RAW converter, dragging the sliders too much degrades the image and introduces quite a lot of noise. Therefore to maximize image quality, you need to nail the exposure in camera.
The example I was given was for a bird in flight, sometimes with landscape as the background and sometimes sky and this was continuously changing, so Auto ISO was chosen. I haven’t had much luck with auto ISO – yes it keeps your chosen shutter and aperture by altering the ISO to suit, but by doing this it exposes for the overall brightness of the scene, rather than just the subject. The subject will come out OK if the background is landscape, but rather dark against a bright sky. You may well get better results on spot metering, but that is rather a small target to continuously keep tracked by the spot meter and in my experience, being slightly off target, you can end up metering for the sky.
I use manual exposure, metering for an 18% grey scale, skin tones, or grass, whichever is convenient. I will set the shutter speed (usually between 1/1,000sec to 1/2,000sec) then set the aperture (on my f4 lens between f5.6 to f8) then dial in the ISO to give me those settings. With luck ISO400, but in practice anywhere up to ISO3,200 and sometimes even ISO6,400. Because I have set the exposure for 18%, skin, or grass, that should give me a good exposure for the bird, regardless of whether it is against the landscape or the sky. After all, it is the bird that I want to nail the exposure for and if the sky burns out a little, so be it. The downside of this method is that I have only set the exposure for those lighting conditions and if the light intensity changes, I need to be aware of it and alter the manual exposure to suit. A bit scary when you first use it, but after a while you don’t need to re-meter, just flick the ISO up or down to suit.
Post processing I use DPP. I have used other products, but DPP is relatively quick, fairly simple and developed exclusively for the Canon RAW file, so it doesn’t need to be a compromise to deal with numerous camera makes. Nothing too radical here though, just do the minimum necessary and don’t work those sliders too much. The more you use them, the more noise you introduce.
Next is the final polish in Photoshop, or whatever editing program you use. If you have used high ISO’s of maybe 3200, or 6400, there will inevitably be some noise. You will have minimized the amount by nailing the exposure and limiting any alterations in your RAW editing, but there will still be some, especially noticeable in flat areas of the same colour, such as the sky. It will probably not be all that noticeable in the subject bird, because that generally has a lot of detail, which masks the effects of digital noise. However, if you apply noise reduction globally to the whole shot, it has the unfortunate effect of softening everything, including the bird. So, I make a selection of the subject and make a new layer of it, then revert to the background layer and apply noise reduction to that. Again, not too much, as little as you can get away with. If you need more, I often try an alternative of adding some Gaussian Blur, but just 0.5 to 1.0 pixel. If you overdo the burr, it can give a Moire effect, which is quite unsightly. Noise reduction will have slightly softened the sky/background areas, but as the subject bird is on a layer above, it is still sharp and carries a lot of detail.
There are three elements to what we refer to as noise – Luminance, Chrominance and JPEG artifacts. The artifacts are a result of over processing, are the most unsightly and need to be avoided. Chrominence is the unusual coloured pixels, usually magenta and cyan in light areas and green and red in shadow areas. Luminence is more described as a grain effect and tends to be more acceptable, as long as it is not combined with obvious Chrominance. I use a little correction for Luminance, a bit more for Chrominance and avoid any previous over processing to keep artifacts at bay. You will need to experiment with these settings to see what is acceptable for you.
If you need to add a “little” sharpening to the bird on the top layer, no problem, but again, don’t overdo it. Size, crop, flatten image and output in your normal format and you should end up with some clean, quality images.
I strive to spend as much time taking the images and as little time playing with them on the computer, but sometimes conditions are against you and you have to use the tools available to you to get it right. The secret is to nail the exposure and from then on, do as little as you dare, rather than as much as you can.
Hope that helps and I welcome your thoughts and suggestions.
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