Hi all, I have a problem with my T6 and 55+250mm f4-5.6 IS STM lens. I acquire (or think I have) focus lock and even though the photos show the focus square is on the face of the Turkey Vulture the photo is blurred. IS is on and I am in AI servo with center weighted focus. The first photo Capture.jpg was taken at TV/1,000,AV/9,ISO 125 and 250mm. The second photo Capture2.jpg was taken at TV/1,250,AV/5.6,ISO160 250mm. I would appreciate any help.
I do not have an answer for you but a question, were you panning the shot of the Turkey Vulture? Maybe panning with this lens is a problem. I had a 70-300mm lens where the IS could be set to pan when shooting, never used it but presumably there is a difference to not panning. At the speeds you are using you could try upping them a bit (by using a higher ISO) and shoot with the IS off and see what you get. Sorry it is not much help but I'm sure someone here will be more help.
do you have links to the full sized, unedited pics? i use that same lens for my birds in flight, and it seems to work well for me. btw, i always pan with IS on with every camera and lens i've used with no issues.
Did you receive a focus confirmation beep? You also have cropped in quite a bit so the bird must have been quite small on the original image (the pixels and fringing are starting to show). Based on a rough estimate of what the original image size probably was, you may be just experiencing issues with the lens tracking focus on a small object. The lens may also be back focusing on the camera. (it is not uncommon for a lens to come slightly back or front focused. You can look up online how to test this. I think the first thing to do is do some more testing to make sure its tracking larger moving objects properly. For achieving focus the one thing to add to what Robert suggested is to make sure to track with the bird and get the focus beep and fire off a series while holding down the shutter and tracking birds flight. That will help with obtaining some of the images in focus when you are tracking a moving object. You may also want to consider a longer lens or adding a tele-converter if you want to get closer to birds.
my first guess was the bird was maybe very small in the frame and had been upsized too much, causing the loss of sharpness.
Thank you for all your replies. The two photos posted where cropped but not severely. I have my ISO on auto and I use manual mode with AF on. What is puzzling is that I get the beep and the green light and in Canon's digital photo professional it showed the focus point right on the head but yet there slightly out of focus,
I'm not sure I can help you with this struggle, but when I have some focus or else issues, I always consult FixThePhoto website, it's really useful one, totally recommend you)
I don't know a straight answer, but I can make some quess work. First, the image stabilization need a little time to act. About a half of a second, or so. And with many lenses, first is a very short movement in the image, and then the image became stabilized. There is also an question if IS is working or not. I have another STM lens, the 18-135, and there is no indicator in the camera to show if iS is working. Only if I am attentive, I can see the effects in the view finder. Another hypothesis is a descentrelized element inside the lens. You can try to test it on a tripod. With/out IS, and with/out AF, to see if you can get a sharp image or not..
i dunno - at 1/1250th of a second, not sure if IS is needed. i'm still wondering how deeply this image was cropped. could also be that the bird moved out of focus after focus confirmation and for some reason the camera wasn't able to track it.
there is nothing wrong with the auto focus of your camera, maybe your expectations of what your camera and lens combo should do is a little on the unrealistic side if i were to go by the size of those crops at a guess i would say that the birds only filled 1/30th of the frame on the original image my advice is if it doesn't full at least 1/8 of your viewfinder your not close enough or have the wrong equipment (no camouflage or teleconverter)
I am wondering if part of your 'problem' is actually motion blur, rather than a focus issue. ISO 125 or 160 seems awfully slow for capturing moving subjects. Also, one of your compatriots, (Ms Anne McKinnell, who's tutorials I would thoroughly recommend) has produced a brief article that might provide you with some helpful pointers ...... http://annemckinnell.com/2016/06/12/how-to-photograph-birds/ Hope this might be of some help.
I think distance is your problem, you simply don't have a long enough lens for the results you want. To still use your lens you need a 2X extender which will double your lens length but has one drawback you loose 2 stops of light or rent a 500mm or 600mm lens for the day. My next suggestion is persistence, keep taking the photos. You learn by your mistakes.
You could try the camera/lens combination at higher ISO's. Set the ISO at 800 or 1600 to up your shutter speed and reduce any possible camera shake not combated by your IS or motion blur from your subject if it is a bird in flight. If you can set your aperture to F8 at ISO 1600 you may find your images improve. I think most of the later DSLR's can shoot at ISO 1600 without introducing too much noise.
ISO isnt the issue, the shutter speed freezes motion and is already quite high 1/1000 or better, the EV of the scene is somewhere around 15 or 16 given the values the OP gave. If he bumps the iso up to 1600 at f 8 that would be 1/16000 of a sec shutter speed, the max shutter speed on the camera is only 1/4000. Shooting a reciprocal of the length of the lens should be sufficient to freeze camera shake . And the 1/1000 - 1/2000 should be a decent range for freezing a car moving as well as birds in flight. An aperture around 9 should have been enough depth of field, and using IS and servo and crabbing a burst of shots should have also aided in grabbing a nice in focus shot. What I can see is in the photos is the actual pixels and some color fringing which mean that the images are cropped from the original and probably at or close to 100% so the bird was relatively small in the frame, and the camera probably had trouble confirming focus. Also if the OP had multi point focus on there may have been other points reading as in focus at a slightly different spot on the focal plane and the camera could have averaged the focus between them. Craig is right, 250mm is a pretty short for birding, if the OP keeps doing what he's doing but fills the frame more with the bird that should solve most of the issues.
Everything you say is good. I should have mentioned that I believe you need a faster speed than the reciprocal of the focal length to improve the sharpness of images that are eventually to be cropped. I may well be totally wrong here, I just remember reading this somewhere and filing it away to help improve my poor images of birds in flight. I have enough problems holding the camera steady for a stationary object let alone one moving, stabilisation may not be able to compensate for my tremors.
Yup reciprocal would handle the hand held camera shake, not necessarily freeze the action. And IS adds a few stops so you can hand hold a 200mm at around 1/50. For freezing action in the shot the factors to consider is how much movement and how fast, for example typically sports are shot around 1/800 to 1/1000 i believe, and moving cars or birds with a long lens would maybe need 1/1000 - 1/2000. In this case the bird is smaller and at a distance so i bet they could have got away with less than 1/1000 as there wasn't that much travel across the focal plane to freeze.
The fact that it focus beeped doesn't mean anything. The bird is in flight so it would have moved between focus acquisition and exposure. You need to be shooting in AI servo mode. In addition, shutter speed needs to be around 1/1600 for large birds in flight
