Getting off Auto

After reading of a Minsmere volunteer’s walkabout with another guide learning about their camera and getting off the Auto setting, I found myself thinking the answers weren’t quite as simple as perhaps people think.  So I thought it might be interesting to talk a little bit about cameras and the various modes.    Besides, it's been a while since we had a techie conversation so I thought I'd let free my inner geek :-)  I use Canon kit, so will tend to use Canon terms, but the principles apply whatever camera you’re using.

The most basic setting on a DSLR (and I’m talking DSLR, again, because that’s what I’m using) is the full Auto mode (the “green box” on a Canon).  Avoid this one like the plague, it leaves absolutely everything up to the camera, including whether or not to use the flash.  Since the pop-up flash built into a camera is a pretty weak beast, only really designed for use over short distances and with “normal” lenses, it won’t help a bit for most telephoto photography out of a hide.  It’ll also annoy other hide users :-)  Exposure compensation isn’t available in this mode either, so it’s very limiting.

P (or Program) is the mode to use if you want the benefits of full auto but with some measure of control.  The camera chooses the aperture and shutter speed that it feels is the best compromise, based on the lens.  It will automatically give you higher shutter speeds for longer lenses (which is important), but will allow you to “shift” the programme as well, giving you some creative control (ie you may be happy to drop the shutter speed to get a smaller aperture and greater depth of field).  Crucially, exposure compensation is available in this mode as well and that’s something particularly useful with birds in flight (where you can end up with silhouettes against a perfectly exposed sky if you’re not careful).  You can also fix the ISO if you wish in P mode, although in general I’d suggest leaving it in Auto unless you’re particularly fussy, modern cameras handle high ISOs well and you’re better off getting used to everything else on the camera before getting too hung up on ISO.

Once you get away from the relatively simple world of green box and P, you enter the murky world of Shutter Priority (Tv) and Aperture Priority (Av).  Actually, these are still automatic modes, but you get the chance to specifically choose shutter speed or aperture, the camera working out what the corresponding other settings should be to get a perfectly exposed shot.  So when do you use which mode?  Entirely up to you.  There’s no correct answer, like much in photography, but Canon give you the options, so it’s worth thinking about which mode is the most suitable before you take a picture.

Many photographers will swear by Av – controlling the aperture, and hence the depth of field (DoF - how much of the picture is in focus) is the most important thing they will tell you.  Well, let’s be contentious.  Nope, frequently that’s nonsense when you’re pointing the lens at a bird, especially if you’ve spent the money on some high quality glass.  To understand why, you need to understand exactly WHAT DoF you’re going to get when you press the shutter button.  The DoF depends on a number of things, principally the sensor size, lens focal length, aperture and distance to the subject.  If you take that staple of birding lenses, the 400mm, on a crop sensor camera like the Canon 7D at a distance of 30ft (which is pretty close when you’re in a hide) you get a depth of field, wide open f/5.6, of just over 4 inches.  I’ve checked some pictures I’ve taken of a kingfisher and the exif tells me they’re at more like 60ft, giving a DoF of over 8 inches.  That’s more than enough to get a kingfisher in focus.  That 8” DoF may be problematic if you get a Marsh Harrier flying past, but guess what?  They’re normally out at 150ft or more, giving you a DoF around the 10ft mark (according to exif on my own pictures).

So why use Av?  Well, it does let you control the DoF, so any bird that is coming in close, especially if large, you’ll benefit from that control of the in-focus areas.  It’s also a good idea to close down the aperture of a lens a stop or so if possible as that will sharpen up the image you get (it benefits all lenses, but particularly ones at the budget end of the market).  Macro or close up shots will definitely need Av as the DoF can end up being a mm or two which is not very helpful.

A lot of the time however, you may find that Tv, shutter priority, is a more useful mode to use for birds – especially those in flight.  Holding a long telephoto lens still is difficult and camera shake is your enemy.  Stabilised lenses can help (IS in Canon-speak) but IS is useless for in-flight shots as you’re waving the camera around deliberately.  The only thing that will freeze the movement (of you and the bird) is a high shutter speed.  There’s a rule of thumb that says you should aim for 1/focal length, but that’s from the world of film (or full frame digital), so using a crop sensor camera, you should use 1/(focal length x crop multiplier).  Example, for that 400mm lens, on full frame, 1/400th sec is a good starting point, but on a crop sensor (like the 7D), aim for 1/400x1.6 or 1/640th sec as a minimum.  That’s for stationary stuff – for in-flight, go higher.  Yes, you may end up with a high-ISO shot, but noise can be dealt with, a blurred pic can’t be saved.

Finally there’s Manual.  That allows you to set both aperture and shutter speed yourself as you’d expect.  Purists will tell you to use this and learn how to use the camera “properly” but personally I don’t buy that.  Learn with whatever modes give you the most satisfaction, you’re meant to enjoy the photography, not find it a chore.  One place I do find manual useful – if I want to stop the lens down a little for sharpness AND maintain control over shutter speed as I’m after in-flight shots, I’ll often use manual with auto-ISO (yes, I know that sounds counter-intuitive).

I’ve realised this has ended up being rather a long waffle, so we’ll leave it there for now!

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Find me on Flickr / All about your camera - The Getting off Auto Index

  • I am a point and click kinda gal - but reading this post has encouraged me too look out the manual of my camera and learn how to use some of the functions.  Thanks.

  • In reply to Angie:

    Very good post Whistling Joe, were in the exif does it show the distance of the subject?

    7D here.

    Jim

    Jim

    My Pictures

  • In reply to James:

    Brilliant I have copied that and will digest at my leisure thanks WJ

  • In reply to James:

    James G said:

    Very good post Whistling Joe, were in the exif does it show the distance of the subject?

    7D here.

    Jim

    It doesn't work on every camera and lens combination, but if you open the full exif in Flickr, you'll see something like
    "Approximate Focus Distance - 98.3" (metres) from this pic
    and 19m on this one

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    Find me on Flickr / All about your camera - The Getting off Auto Index

  • In reply to Whistling Joe:

    Sadly it does not show in the 40D or 7D exif with any of my 5 canon lenses :(

    Jim

    Jim

    My Pictures

  • In reply to James:

    Interesting - the 7D with 100-400 works.  What lenses do you have?

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    Find me on Flickr / All about your camera - The Getting off Auto Index

  • In reply to Whistling Joe:

    I have the 60mm macro the 70-300 IS not the L lens the 300mm L an 400mm L Joe.

    EDIT

    And kit lens

    Jim

    Jim

    My Pictures

  • In reply to James:

    Hmm, interesting. I have both the 300mm f/4 and the 400mm f/5.6 (which are the ones you mean I assume). I'll need to search for images taken on the 7D with those lenses (the 300 is normally on Mrs WJ's 40D), but 40D and 300 definitely works, so it's strange you don't see it. Do you take jpg or RAW and post-process? Maybe that's the difference....

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    Find me on Flickr / All about your camera - The Getting off Auto Index

  • In reply to Whistling Joe:

    I will try with the 40D and 300mm Joe.

    I use Raw and post-process with Digital Photo Professional.

    Canon EF 70-200mm f4 L USM Lens

    Canon EF 300mm f4 L IS USM Lens

    Canon EF 400mm f5.6 L USM Lens

    Jim

    Jim

    My Pictures

  • In reply to James:

    File name IMG_0651.CR2

    File Size 24.0MB

    Camera Model Canon EOS 7D

    Firmware Firmware Version 2.0.3

    Shooting Date/Time 18/04/2014 07:06:05

    Author James Bennett

    Copyright Notice xxxxxxxxxxxxxxxxxxxxxx

    Owner's Name

    Shooting Mode Aperture-Priority AE

    Tv(Shutter Speed) 1/1600

    Av(Aperture Value) 4.5

    Metering Mode Partial Metering

    AE lock ON

    Exposure Compensation 0

    ISO Speed 400

    Auto ISO Speed OFF

    Lens EF300mm f/4L IS USM

    Focal Length 300.0mm

    Image Size 5184x3456

    Image Quality RAW

    Flash Off

    FE lock OFF

    White Balance Mode Auto

    AF Mode One-Shot AF

    AF area select mode Manual selection

    Picture Style User Defined 1(Standard)

    Sharpness 3

    Contrast 1

    Saturation 0

    Color tone 0

    Color Space sRGB

    Long exposure noise reduction 0:Off

    High ISO speed noise reduction 3:Disable

    Highlight tone priority 0:Disable

    Auto Lighting Optimizer Disable

    Peripheral illumination correction Enable

    Dust Delete Data No

    Drive Mode Low-speed continuous shooting

    Live View Shooting OFF

    Camera Body No. xxxxxxxxxxxx

    Comment

    Jim

    Jim

    My Pictures