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    Getting Clean Images

    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:

    1. The gremlins are in my system and I am unable to answer PM’s at the moment.
    2. There is no short easy answer and I need to go into more detail than a PM warrants.
    3. There may be other members that could benefit from my thoughts.
    4. 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.
    Colin

    #2
    Re: Getting Clean Images

    That’s a very good ‘write-up’ Colin....thanks for taking the time....I’ve been thinking of making more use of DPP recently so this has been the straw that has persuaded me to not just rely on LR for everything.
    Rather than layers the mask feature in LR avoids sharpening where you might not want it....and similarly for noise reduction I think (I’m away from my computer so cant check that......either that or use a brush for selective noise reduction.
    (I have layers phobia by the way!)
    Brian Vickers LRPS

    brianvickersphotography.com

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      #3
      Re: Getting Clean Images

      Excellent write up Colin

      Tom

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        #4
        Re: Getting Clean Images

        Excellent Colin. I also use DPP, and yes spend as little time playing around on the computer - what I see in the view finder, is what you get.
        Trev

        Equipment - According to the wife more than a Camera Shop got

        Flickr:
        https://www.flickr.com/photos/trevb2639/

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          #5
          Re: Getting Clean Images

          Nice write up. I am pleased to find that I do much the same, with as much processing as possible done in DPP and only resorting to Affinity if I need to do some selective processing with masks/layers. The latest DPP does do selections now but not very well, IMO.
          Chris
          80D - 10-18 IS STM - 15-85 IS USM - 55-250 IS STM - 50 f/1.8 STM - 100-400L IS II USM - 100 f/2.8L Macro - 1.4x III

          Comment


            #6
            Re: Getting Clean Images

            This is an excellent piece by Colin C, worth reading more than once.

            "Nail the Exposure" - drummed into me by my late father with his separate exposure meter and 25 & 50 ASA (ISO) slide films. I've never forgotten that.
            Bob


            EOS 6D mkII, EOS 6D, BG-E13 Grip, EOS 30 (Film), EOS M5, EF-M 22mm f2.0, EF-M 18-150mm, 35mm f2.0 IS, 50mm f1.8 STM, 17-40 f4 L, 24-105 f4 L IS, 70-200f4 L IS, 430EX II, 270EX II, Manfrotto 190XDB +496RC2 tripod, Op Tech straps & Think Tank bags.

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              #7
              Re: Getting Clean Images

              "Nail the Exposure" - drummed into me by my late father with his separate exposure meter and 25 & 50 ASA (ISO) slide films.
              Even more important with slide film Bob. A third of a stop would make all the difference as there was no latitude for error, unlike film.
              Colin

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                #8
                Re: Getting Clean Images

                Good info Colin
                Hanging on in quiet desperation is the English way

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                  #9
                  Re: Getting Clean Images

                  Ha, thanks Colin, only just seen this, very informative, I must give manual a try for BIF, have never used it for the reason mentioned, the Barn Owls constantly move from a sky background to having dark hedges behind them and before I had changed the ISO they would have moved again.
                  I think this is particularly problematical with my regular pair because they virtually always hunt in the field adjacent to their roost, which has dark thorn hedges on 3 sides and is only partially open on the 4th side where I am able to stand.

                  I do have PS6 but have just never been able to get my head around it, haven't the faintest idea about Layers, I will just have to bite the bullet and sit and watch some tutorials.

                  Thanks again and watch this space for some manual shots, my problem is most certainly 'in camera'

                  Paul

                  Comment


                    #10
                    Re: Getting Clean Images

                    Great write up Colin , I too shoot manual but with auto ISO when it is likely my subject will be moving against different backgrounds but as you say it does not always give the best results and I find the camera usually plays safe choosing a higher ISO than the scene probably needs . I am interested in your method of setting exposure at 18% against a fairly neutral background hopefully always give you a decent exposure of the subject irrespective of the background . Could you please elaborate on the process you adopt to set this up as I am unsure of exactly you achieve this ?
                    Steve ( LSINWP )
                    1DX, and 7D2 ,500mmf4mkii, 300mmf2.8, 400mm f5.6 , 100mm - 400mmmk2 ,70-200mm f2.8 ,24-105mm f4, 100mm f2.8 macro , 1.4x converter, 2x converter and a big dose of luck !!

                    Comment


                      #11
                      Re: Getting Clean Images

                      Excellent write up, thank you Colin.

                      I've not been out much over recent years with the camera and have lost my touch and this has reminded me of the things that I used to do but have since forgotten. I must get out more often and start practicing again and maybe I will start enjoying my photography again.
                      I have only taken a little under 1500 photos since buying my 7D markII 15 months ago and that was mainly two trips to Slimbridge, once in January 2018 & again in October 2018.
                      Canon EOS R6 Mark II, Canon RF 100-500mm f4.5-7.1L, Canon RF 24-105mm f4L
                      Please note: I do not have or use Photoshop

                      flickr

                      Comment


                        #12
                        Re: Getting Clean Images

                        Originally posted by Hereford_EOS View Post
                        Excellent write up, thank you Colin.

                        I've not been out much over recent years with the camera and have lost my touch and this has reminded me of the things that I used to do but have since forgotten. I must get out more often and start practicing again and maybe I will start enjoying my photography again.
                        I have only taken a little under 1500 photos since buying my 7D markII 15 months ago and that was mainly two trips to Slimbridge, once in January 2018 & again in October 2018.
                        Good to hear from you again. You never forget!

                        Hope you can get out soon.
                        Bob


                        EOS 6D mkII, EOS 6D, BG-E13 Grip, EOS 30 (Film), EOS M5, EF-M 22mm f2.0, EF-M 18-150mm, 35mm f2.0 IS, 50mm f1.8 STM, 17-40 f4 L, 24-105 f4 L IS, 70-200f4 L IS, 430EX II, 270EX II, Manfrotto 190XDB +496RC2 tripod, Op Tech straps & Think Tank bags.

                        Comment


                          #13
                          Re: Getting Clean Images

                          mainly two trips to Slimbridge, once in January 2018 & again in October 2018.
                          We must organise a get together at Slimbridge again and make the invitation to all members that can make it. Perhaps we can drink a toast to Indiana Jones (AKA Nathaniel) while we are there and celebrate his first ever Kingfisher shot ............... of a carving of a Kingfisher!
                          Colin

                          Comment


                            #14
                            Re: Getting Clean Images

                            Did you see my question Colin ?
                            Steve ( LSINWP )
                            1DX, and 7D2 ,500mmf4mkii, 300mmf2.8, 400mm f5.6 , 100mm - 400mmmk2 ,70-200mm f2.8 ,24-105mm f4, 100mm f2.8 macro , 1.4x converter, 2x converter and a big dose of luck !!

                            Comment


                              #15
                              Re: Getting Clean Images

                              Originally posted by colin C View Post
                              We must organise a get together at Slimbridge again and make the invitation to all members that can make it. Perhaps we can drink a toast to Indiana Jones (AKA Nathaniel) while we are there and celebrate his first ever Kingfisher shot ............... of a carving of a Kingfisher!
                              That would be good
                              Canon EOS R6 Mark II, Canon RF 100-500mm f4.5-7.1L, Canon RF 24-105mm f4L
                              Please note: I do not have or use Photoshop

                              flickr

                              Comment

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