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Thread: Another Robin

  1. #1
    BenPonti
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    Default Another Robin

    I'm still having problems with focusing using my 50D. This shot was taken using the 100-400mm lens but on my old 400D. Cropped of course, but I think it disproves a problem with the lens. Could it be the camera (50D) or me getting old!
    Comments more than welcome.

    TV 1/400
    AV 5.6
    Focal length 365mm
    Al Servo AF
    Drive mode: Continuous shooting

  2. #2
    Axel Hildebrandt
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    I like the head-on pose and open beak in this one. I would give it more room and wish the sun would have been behind you and would tone down the highlights more. Keep them coming!

  3. #3
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    Ditto Axel here
    TFS

  4. #4
    Publisher Arthur Morris's Avatar
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    Like the open mouth but there are huge problems here with the harsh filtered off angle light... The shadows are blocked up and the highlights are either way too bright or over-exposed. You need to find subjects that are evenly lit and learn to point your shadow right at the subject.
    BIRDS AS ART Blog: great info and lessons, lots of images with our legendary BAA educational Captions; we will not sell you junk. 30+ years of long lens experience/e-mail with gear questions.

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  5. #5
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    Nice shot, well timed. I imagine that view down its throat is the last view that many worms have.
    You mentioned a focusing problem with the 50d, have you been having the issues on all shots or just on long distance shots?

    Eric
    Faces of Nature Photography
    www.ericjvirkler.com

  6. #6
    BenPonti
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    Thanks for the comments. I take on board the advice re lighting and exposure though an not sure what 'point your shadow right at the subject' means exactly.
    As far as focusing issues are concerned with the combination of the 50D and 100-400mm lens - at the moment I'm concentrating on the birdtable in the garden, a distance of about 7mtrs.

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    Lifetime Member Stu Bowie's Avatar
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    Ben, with regards to focussing with the 100-400, are you changing your minimum focussing distance on the lens ( 2.5-6.5) Sometimes, you think the subject is further than the 6.5m, and it isnt, resulting in an OOF image. I often change between 2.5- 6.5 and 6.5 to infinity. Hope that helps.

  8. #8
    BenPonti
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    Hi Stuart. Are you referring to the switch on the lens barrel? If so, mine reads: 1.8m - infinity and 6.5m - infinity. I tend to keep on the 1.8 - infinity.

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    Publisher Arthur Morris's Avatar
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    Quote Originally Posted by BenPonti View Post
    Thanks for the comments. I take on board the advice re lighting and exposure though an not sure what 'point your shadow right at the subject' means exactly.
    As far as focusing issues are concerned with the combination of the 50D and 100-400mm lens - at the moment I'm concentrating on the birdtable in the garden, a distance of about 7mtrs.
    Point your shadow at the bird means that the sun should be coming right over the top of your head as you point the lens at the subject.

    Have you done any basic sharpness tests to make sure that the problem is with the camera or lens rather than with the operator?

    Respectfully.
    BIRDS AS ART Blog: great info and lessons, lots of images with our legendary BAA educational Captions; we will not sell you junk. 30+ years of long lens experience/e-mail with gear questions.

    BIRDS AS ART Online Store: we will not sell you junk. 35 years of long lens experience. Please e-mail with gear questions.

    Check out the new SONY e-Guide and videos that I did with Patrick Sparkman here. Ten percent discount for BPN members,

    E-mail me at samandmayasgrandpa@att.net.










  10. #10
    BenPonti
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    'basic sharpness tests ' - been trying to do different tests all week though suspect I'm doing something wrong. I downloaded quite detailed instructions re. the moire tests and think that in the past I may have been a little over zellous with the microadjustment. I'm now back to 0 or maybe +5 but will have to wait until the weather improves so I can get a reasonably fast shutter speed.

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    Publisher Arthur Morris's Avatar
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    A quick search of the BAA Bulletin Archives turned up the info below. Everyone should subscribe :) :) :) They are free and as you will see, loaded with great info.

    You can access the Bulletin Archives via the link on the home page at
    http://www.birdsasart.com. You can find all of Bulletin 289 here: http://www.birdsasart.com/bn289.htm

    SHARPNESS TESTING

    I receive several e-mails each week from folks who state that this camera does not focus properly or that that lens is not sharp. In 99% of the cases I am sure that operator error rather than equipment malfunction is the cause. That said, on rare occasion, folks using quality equipment from Canon of Nikon do experience real problems with focusing accuracy.

    If you are handholding, please do not complain about unsharp images. I was walking around in Sabine Woods late yesterday afternoon. It was cloudy dark. I was working at ISO 800 with shutter speeds of about 1/60th second and even slower at times. There were two folks walking around handholding 500 f/4 lenses; they might as well have gone fishing as there was no way that they could create a sharp image without a tripod in those conditions. It is best to work on a tripod at all times when using your longest lens (unless you are handholding for flight or for action).

    Another factor to consider is that most of the folks who write complaining of unsharp image are using cameras with 1.6X or 1.5X multiplier effects. They need to realize that these cameras multiply vibrations and movement caused by operator error by the square of the equivalent focal length!

    If you are using a tripod you need to check and note the shutter speeds of your unsharp images. I had one guy on an IPT complaining that none of his images were sharp. I checked his set-up and saw that he was working in near darkness at ISO 100 with shutter speeds in the 1/8 to 1/15 second range. Making sharp images with a long lens at such slow shutter speeds is simply not possible for most folks. When working at long effective focal lengths I am confident that I can make sharp images down to 1/60 second as long as I have time to lock the tripod head and provided that the bird does not move during the exposure. With the prime lenses alone, I can usually get down to 1/30 second. With the relatively new Canon 800mm lens and its new 4-stop IS system, I have made some sharp images at shutter speeds as slow as 1/6 sec.

    Below are two simple tests to determine if you have faulty equipment.

    #1: Tape a sheet of newspaper to a sunlit outdoor wall on a relatively still day. Make sure that it is as taped down as flat as possible. (A magazine cover with fine print or a plastic or cardboard test chart are of course better options.) Mount your telephoto rig on a tripod. Lock down the tripod and the lens collar. Make sure that you are beyond the minimum focusing distance of your lens and that the distance range switch (if your lens has one) is set to full. Make a few images at the wide open aperture using both One-Shot or AI Servo with Canon gear or Single (S) or Continuous (C) with Nikon. Then do the same thing at f/8. As long as the wall is sunlit you will have more than enough shutter speed to know that your focusing issues are not caused by too-slow shutter speeds. Now download your images and check them for accurate focusing. If all of the images are sharp, then you can be sure that your unsharp images were being caused by operator error.

    #2: Stand well off a somewhat busy road with the sun angled so that the approaching vehicles are coming right down sun angle. Use the wide open aperture and choose an ISO that results in shutter speeds greater than 1/2000 sec. Choose AI Servo (Canon) or Continuous (Nikon) and select the center AF sensor. As the cars approach, place the central sensor on the license plate and hold the shutter button down once focus is acquired. Even this simple task requires some practice so be sure to take lots of images. Download the images and sort them into two groups: sharp on the license plate and unsharp on the license plate. Now using an application that allows you to see the position of the active focusing sensor, in this case the central sensor, note the position of the sensor in the unsharp images. If the sensor is consistently on the license plate and the images are unsharp, then you likely have equipment problems. You can repeat this test with various camera bodies and various lenses in an effort to determine the cause of the problem. When you are pretty sure that you have an equipment problem it is best to send the gear to the manufacturer along with a CD of the test images.

    In most cases, folks will learn that their equipment is perfectly fine but that their poor sharpness techniques are the cause of the unsharp images. Do also realize the importance of subject movement. While working at the Cozad Ranch probably well more than half of my images were unsharp. This was due in most cases to subject movement. In other cases, the unsharp images were a result of the AF system being unable to maintain sharp focus on the tiny songbirds as they leaped off of their perches. It is important to understand and to realize the limitations of our equipment.
    BIRDS AS ART Blog: great info and lessons, lots of images with our legendary BAA educational Captions; we will not sell you junk. 30+ years of long lens experience/e-mail with gear questions.

    BIRDS AS ART Online Store: we will not sell you junk. 35 years of long lens experience. Please e-mail with gear questions.

    Check out the new SONY e-Guide and videos that I did with Patrick Sparkman here. Ten percent discount for BPN members,

    E-mail me at samandmayasgrandpa@att.net.










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