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Thread: Question about telephoto lenses, aperture, etc

  1. #1
    FlyingSquirrel's Avatar
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    Question about telephoto lenses, aperture, etc

    I just got a Canon 400mm 5.6 L. What I am wondering is what kind of aperture I should be using for birds and wildlife. I don't understand how people can shoot wide open. Isn't that too shallow of a DOF to get any kind of good bird shots?

    I have also wondered this about the pro lenses that have max apertures of like 2.8. I don't understand how someone would pay so much for a crazy big fast lens like that- how can 2.8 be usable for wildlife? Why spend $10,000 for an insane lens that is so fast- do they really shoot at 2.8 so much? I may be missing something....

    In fact this just occurred to me...with a huge pro lens stopped down a bit, for example a 2.8 stopped down to 5.6 or 8 or something, would that aperture still be "bigger" and let more light in than my lens at the same aperture? Not sure if that makes sense.

    Thanks for any help

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    Re: Question about telephoto lenses, aperture, etc

    Matt, What you have to remember is the distance at wich the target will be. The further away the more shallow DOF you can get away with. A small bird up close you will suffer at less than F8. But for 20-30 yrds or more....wide open will most times work fine. Where you will have trouble is group shots that are semi close.

    I typically work from F8 up or down if needed. I find F8 is more times than not enough at close distance unless there is more than one bird. At further distances if I need more shutter speed I will open it up some as I will not need F8.
    Last edited by jeeperman; 6th February 2013 at 07:16 AM.

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    Re: Question about telephoto lenses, aperture, etc

    f5.6 at 25 feet you will have a 3" DOF so make sure your birds are skinny. Stop down to f8 and you get a gigantic 4.2" more or less - no problem for someone of your ability. Check it out for yourself http://www.dofmaster.com/dofjs.html

    Cheer up f5.6 at 100 yards DOF is about 37 feet. Go to Australia and take photographs of kangaroos.

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    Re: Question about telephoto lenses, aperture, etc

    Hi Matt,

    The 400mm f5.6 is a very good lens when wide open. On a crop camera it will be hard to tell the difference across the frame between wide open and stopped down to f8. I shoot this lens exclusively without a tripod. The lens is so light that a tripod is against the whole point of the lens: to shoot wildlife handheld.

    Take note that you will definitely notice any camera shake in your photos if you have too slow a shutter speed. This lens has no stabilisation and so you should stick to the 1/Effective Focal Length (EFL) rule. If you shoot in auto mode then your camera will do this for you. However if you like to set the exposure then use at least 1/400s for 35mm equivalent or 1/640s for a crop. Note that if you want to crop your image you are increasing the EFL. So you will need higher shutter speeds again or you will see blurring in the cropped image as it becomes enlarged.

    I have found that you will probably get more usable results if you shoot at twice 1/EFL. So on a crop camera you will need 1/1250s to allow for subject movement and some image cropping. With these sorts of shutter speeds shooting wide open becomes a necessity in order to keep the ISO low.

    As for depth of field, it should be enough if your focus is correct. To try out the depth of field try shooting something of a similar size to your intended target, e.g. try a coke can on a wall at 10 meters away to simulate a small bird. Stand at a 45 degree angle to the wall and you will see that the can is in focus and the wall nicely blurs out of focus before and after the can.

    Focussing perfectly is a situation where a camera with Auto-Focus Micro Adjustment (AFMA) is useful. You can tune the lens exactly to your camera. If you do not have this and have a high number of missed focus shots then you can get Canon to calibrate the lens and camera for you. But usually technique has a lot to do with it so concentrate on that:

    - Always brace yourself against a solid object if you can (e.g. a wall or tree). Otherwise sit/kneel down and brace against your own body
    - I like to brace the very end of the lens at the hood but experiment for yourself
    - Keep your shutter speed high, a grainy non-blurred shot from high ISO is better than a blurred shot
    - For moving subjects use continuous focus tracking
    - Take shots in burst of three or more as one will usually be better
    - For fixed subjects try and breath out slowly when taking the shot to steady yourself, like a sniper
    - Panning shots will be less prone to hand camera shake since the movement steadies your shaking

    You can test your own hand shake but taking about 5-10 shots of a flat wall target at each interval of a set of decreasing shutter speeds. Try shooting a piece of text or poster on a wall at 1/4000, 1/2000, 1/1000, 1/500, 1/250, 1/125, 1/60s, ..., good luck. See how many of the 5 shots were acceptable to you when inspected on the computer. It is good to keep in your head what is your 50% and 90% keeper rate. For example I at 1/EFL I am above 90%, and at 2/EFL I get a 50% keeper rate. But I can't shoot much slower without good support.

    You may want to invest in a different camera strap. For long lenses I use the lens tripod rind to attach to my strap and the camera-lens combination naturally hangs in a balanced upside down position. I use a Black Rapid strap but there are lots of similar ones so check them out.

    Also try the lens for close up shots. Get low to the ground and shoot a flower with the background at least the distance you are to the subject. You will be amazed at the subject isolation you can get with a telephoto lens. This holds true for all uses of telephotos. If the background is very far from the subject then it will really enhance the subject.

    Have fun with the new lens.

    Alex
    Last edited by herbert; 6th February 2013 at 11:38 AM.

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    Re: Question about telephoto lenses, aperture, etc

    Another way to stabilize the 400mm f/5.6L lens is to use a monopod. I like to use a tilt head when shooting with a monopod. When following action, I don't have the tilt head locked down but, leave it loose so I can efficiently follow that action. The monopod can still provide staibilty for your shots, even with the head fairly loose.

    When shooting still subjects using a monopod, I will often lock the tilt head. I will then use my left hand to hold the pod (with the strap around my wrist) while the other hand operates the camera.

    Shooting movng subjects, I keep the head fairly loose and use one hand on the lens and the other on the camera.

    It takes a bit of practice to learn this technique but it works just fine.

    I will still use the maximum speed commensurate with the ISO capability of my camera.

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    Re: Question about telephoto lenses, aperture, etc

    A wide open lens will never be as sharp as working around the mid point, Matt; and using the other extremity with very narrow apertures can also cause problems.

    However, this is less noticeable with better quality lenses. So a really good lens wide open may give better quality (excluding depth of focus issues) than a lower quality lens at it's 'sweet spot'.

    This review site gives test results for a wide range of lenses; and you will note that some of them give rather poor results at certain positions while others perform much more reliably.

    http://www.photozone.de/Reviews/overview

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    Re: Question about telephoto lenses, aperture, etc

    Quote Originally Posted by flyingSquirrel View Post
    I just got a Canon 400mm 5.6 L. What I am wondering is what kind of aperture I should be using for birds and wildlife. I don't understand how people can shoot wide open. Isn't that too shallow of a DOF to get any kind of good bird shots?...
    You tell me.

    Question about telephoto lenses, aperture, etc
    50D. EF 400mm f/5.6L USM. iso 400, f/5.6, 1/3200s. handheld.

    Question about telephoto lenses, aperture, etc
    XT. EF 400mm f/5.6L USM. iso 400, f/5.6, 1/4000s. handheld.

    [Zoo shot]
    Question about telephoto lenses, aperture, etc
    XT. EF 400mm f/5.6L USM. iso 400. f/5.6, 1/250s. monopod.



    As was said, subject distance also plays a big role in DoF and background blur.

    Because the 400/5.6L is unstabilized and pretty much as sharp at f/5.6 as it is at f/8 or f/11, I shoot with it wide open all the time, mostly to get shutter speeds up.

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    Re: Question about telephoto lenses, aperture, etc

    Matt, thank you for posting this. Very informative. Wow, Kathy your bird shots are gorgeous!
    Last edited by Brownbear; 7th February 2013 at 10:33 PM.

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    FlyingSquirrel's Avatar
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    Re: Question about telephoto lenses, aperture, etc

    It never ceases to amaze me how generous everyone on this forum is with their time, being so willing to share their knowledge and experience. I will one day return the favor when I have worthwhile information to give to others

    So, thank you to everyone that responded. The things that I've gleaned from your posts have been an immense help, and will no doubt set me on the proper path to learning this long lens.

    Here is a summary of the key points I've noted, among many:

    * to start, 1/800 - 1/1000 minimum ss is probably going to get me the most keepers
    * wide open is fine at a good distance (DOF calculators and general experience will help to know when to stop down, light conditions permitting)
    * if needed, use higher ISO because sharp and grainy is better than an out of focus reject
    * try a variety of shooting, support, and bracing techniques
    * experiment
    * practice practice practice
    * I am a sniper; the camera is an extension of my body, and my body is part of the earth

    I should note that my standards are extremely high, and if any photo at 100% is not super sharp, it will be trashed. Thus, I will not be disappointed or surprised to have 1% or less keeper rate to start, though I personally believe I can and will do better than that.

    I do still have one more question, which was in my original post. This is not really relevant nor will it help me in any way, other than allowing me to understand lenses a bit more. The question was:

    with a huge pro lens stopped down a bit, for example a 2.8 stopped down to 5.6 or 8 or something, would that aperture still be "bigger" and let more light in than my lens at the same aperture? So in other words, would the actual size of the 5.6 aperture on a 2.8 big glass be physically larger than my lenses' 5.6? I am talking about comparing the 5.6 opening between both lenses, NOT the relative sizes within each lens. (Again, I get that this doesn't matter, but I'm just curious)

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    pnodrog's Avatar
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    Re: Question about telephoto lenses, aperture, etc

    No, the aperture sizes at the same f stop for 400mm lenses will be identical regardless of the maximum aperture for each lens.

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    Re: Question about telephoto lenses, aperture, etc

    Some quick thoughts Matt,

    1. 1/800 to 1/1000 is great ... if you can get it, but you'll only get 1/800th on a sunny day - and only then if the bird is front lit ... so you're probably going to have to work the ISO a bit ... and that in turn has consequences for dynamic range, which bird shots can challenge a bit. So just be aware that the practice may not be as easy as the theory.

    2. A correct (3 pass minimum) sharpening workflow is just as critical as correct focus.

    3. Have a look around www.birdsasart.com for some good stuff.

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    inkista's Avatar
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    Re: Question about telephoto lenses, aperture, etc

    Quote Originally Posted by Christina S View Post
    Matt, thank you for posting this. Very informative. Wow, your bird shots are gorgeous!
    Um, if you meant Kathy then you're welcome and thanks!

    Quote Originally Posted by flyingSquirrel View Post
    * I am a sniper; the camera is an extension of my body, and my body is part of the earth
    You learn quickly, my young Padawan....

    A few additional technique thingies that can help (importance varies greatly on this list).

    • Shoot with both eyes open. Makes things a lot easier to have more than just the 3-degree FoV of the 400mm to scan your surroundings with, either to find the BiF, or for personal safety.
    • Master your burst modes: short controlled bursts. Understand how burst mode affects your autofocus in the different AF modes, and when your buffer's gonna be full.
    • Master your AF. Servo vs. One Shot. They're there for a reason. Know the difference and which is going to work and why. Also mess about with the different AF point settings to see if a single point, the whole matrix, or part of the matrix is what you need.
    • Master your metering modes. Center-weighted and spot metering are beloved of bird photographers because the sky often meters differently from the bird.
    • focus limit switches are there for a reason. If you want to speed up your AF lock, use the focus limit switch they put on the 400/5.6. Using the farther distance (smaller range) limits where the camera will "hunt" for AF and speeds up focus.
    • Back-button AF and Custom modes. If you haven't yet learned how to back-button AF, I'd highly recommend giving that a whirl, too. Removing the AF function from the shutter button and putting it on one of the back buttons (* or AF-ON) can really help with speed/precision. Also Custom modes can be useful. I have a 50D, which has a C1 and C2 on the mode dial. I've got C1 set up as my "birding mode": start in shutter priority 1/1000s, iso 400, high speed burst mode, center-weighted, back-button AF using the * button, etc. etc. That way, I can turn back-button AF on and off with a simple twist of the dial (on the 50D, it's two custom function settings together. If you have a 7D, though, probably not as much of a PITA).


    And on top of all that, with bird shots, field craft may actually be the most important skillz to get the shot. Knowing your subject and how to get close without disturbing your subject is probably the #1 factor to getting a good shot. 400mm, you will quickly find, is often not long enough. You're still going to be cropping. Just don't be that annoying photographer birders complain about.
    Last edited by inkista; 7th February 2013 at 05:48 PM.

  13. #13
    FlyingSquirrel's Avatar
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    Re: Question about telephoto lenses, aperture, etc

    Thank you, L.Paul, for answering my random question. It's nice to know the answer finally to satisfy my curiosity!

    Thank you Colin, for the tips. I figured it would not always be so easy When you refer to "3 Pass" sharpening, are you referring to sharpening at 3 different stages within the entire workflow? i.e. Capture, Creative/Normal, and Output?

    Thank you, Kathy. I am familiar with many of the additional tips you mentioned, and understand and have used many of these settings and techniques. There are some though, that I have not had much experience with (such as ADVANCED autofocus settings on the 7D). It is nice to be reminded of all of these things though, so I appreciate you mentioning everything, and it spurred me to review my 7D manual regarding AF settings and such. I do plan to have Custom (C1, C2, etc) dial modes set up for various subjects i.e. wildlife, macro, landscape

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    Re: Question about telephoto lenses, aperture, etc

    Quote Originally Posted by flyingSquirrel View Post
    Thank you Colin, for the tips. I figured it would not always be so easy When you refer to "3 Pass" sharpening, are you referring to sharpening at 3 different stages within the entire workflow? i.e. Capture, Creative/Normal, and Output?
    Yes - go to the head of the class!

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    Re: Question about telephoto lenses, aperture, etc

    I do not have a 400 so have not stepped in. Glad I did though, tons of top advice here.

    Just to reiterate - apart from all the shooting methods, camera usage, etc Kathy mentioned the key word ie FIELD CRAFT. Every bird is different even of the same species but they tend to have habits. Learn those and you should be good to go. Camera craft you need to master in the field.

    Start with bigger birds. BIFs start with gulls and ducks.

    One of the best free learning resources is here http://digitalbirdphotography.org/contents.html

    Best of luck.

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    PRSearls's Avatar
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    Re: Question about telephoto lenses, aperture, etc

    Bobo, thanks for the link to Digital Bird Photography. Real good information.

    Paul S

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    Re: Question about telephoto lenses, aperture, etc

    Indeed, Bobo, it's always nice to hear your input. That is a good link; I have already been reading it, started last week...soooo muuuuuch innfoooormmmattttioooon!!!!

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    Re: Question about telephoto lenses, aperture, etc

    One other good resource is Arthur Morris's site which Colin has already linked.

    He has ebooks specifically about the setting up of various cameras - I think has one one for the 7D, 5D3 and 1Dx. Not free though.

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    Re: Question about telephoto lenses, aperture, etc

    What you need to understand is that the aperture (f/No.) is actually the focal length of the lens divided by the diameter of the aperture so an aperture of say f/8 on a 200mm lens is physically 25mm in diameter. The same size 'hole' (25mm) on a 100mm lens would be f/4. Which is why zoom lenses have a range of maximum apertures depending in the actual focal length in use, the physical size of the aperture remains the same.

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    Re: Question about telephoto lenses, aperture, etc

    Quote Originally Posted by keith201 View Post
    What you need to understand is that the aperture (f/No.) is actually the focal length of the lens divided by the diameter of the aperture so an aperture of say f/8 on a 200mm lens is physically 25mm in diameter. The same size 'hole' (25mm) on a 100mm lens would be f/4. Which is why zoom lenses have a range of maximum apertures depending in the actual focal length in use, the physical size of the aperture remains the same.
    Unless you are shooting a constant aperture pro lens, where the maximum aperture is constant throughout the entire focal length of the lens.

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