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Messages - nightbreath

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If you're using phase detect AF and selecting a single AF point, the camera is not going to focus somewhere else in the scene, it will use only that AF point.  (Side note - even Spot AF uses an area a little bigger than the AF point representation in the viewfinder; regular AF is even larger relative to the little box.)  So, if Live View on a particular spot consistently results in correct focus, and the phase detect AF is giving you about 80% front-focused shots, then your phase detect AF system needs calibration, and that's what AF microadjustment is for.

I'm not sure what Phase Detect is, could you please describe things in more details?
What I do is:
1. Turning on my camera.
2. When looking through the viewfinder focusing at a subject by using central point (the big one or the small one, it doesn't matter).
3. Pressing the shutter release button half way to focus.
4. When I hear focus confirmation sound I press the button down.
5a. If the area that my focus point was pointed at has high contrast I have a crisp shot.
5b. If the area was not contrast enough (see my first two samples at the first message), I get front-focus.

P.S. I'm always using one focusing point for One Shot. AI Servo is normally used by me for birds and other fast moving creatures, but I didn't check its accuracy, so can't say if there's an issue with AI Servo too.

The issue I experience is the same on both 50mm f/1.4 and 85mm f/1.2. I don't think it's about lenses, I think it's localized in body autofocusing functionality. But I just wanted to get a hint from guys here that this is an issue, not normal behavior.

Have you done an AF microadjustment??

I tried some day, but it wasn't a good idea as I'm not getting consistent results as those are dependant on subject's contrast. I've reset all camera settings before my tests, so it is at its default setting "turned off".

Thank you for your responses. I've run more tests and identified the problem.

I have updated my first message, so the latest information can be found there. Could you please look at it and leave a comment?

I have a Canon 7D and few lenses. The issue I’m experiencing for more than 2 years is related to autofocus with fast primes and can be replicated when camera is focusing at a non-contrast area. It doesn't matter what type of focusing / focusing point I use – I hear focus confirmation in the same manner as if camera has focused properly, but when I make the shot I see that it didn’t.

I've run several tests and identified that the lens AF is inconsistent comparing to Live View autofocus, when area in focus has no contrast. When I use lens AF in ~80% shots I'm getting front-focus issue.

Attached are crops from my tests, red square is the focusing point. Could someone confirm that this is normal behavior? Or should I sent my camera to Canon?

P.S. Shots were taken at ISO 800, 1/80 of a second, f/1.2 and f/1.4, using tripod.

Animal Kingdom / Re: Show your Bird Portraits
« on: February 11, 2012, 12:11:57 PM »
and some more...

Animal Kingdom / Re: Show your Bird Portraits
« on: February 11, 2012, 12:11:06 PM »
Sharing mine too...

Lenses / Re: Canon 85L vs. 135 L in terms of focal length
« on: February 09, 2012, 01:49:09 PM »
Thank you everyone for your input   :)

Lenses / Re: Canon 85L vs. 135 L in terms of focal length
« on: February 09, 2012, 09:02:23 AM »
I've already looked through this: http://pixel-peeper.com/lenses/canon/ and just wanted to hear more on the topic. Maybe someone owns both lenses?

I'm not able to rent them, as we don't have a service for this in my country.

Lenses / Canon 85L vs. 135 L in terms of focal length
« on: February 09, 2012, 08:35:16 AM »
I have a question related to different focal lengths and want to decide which one would work better for me.

I'm planning to go full-frame this year and want to have better understanding of the difference between 85mm and 135mm focal lengths for portraits. I love fixed lenses and looked through several sample shots made using both, but there are things that you can't predict by just looking at those pictures. I'm not able to try both by myself, that's why I'm asking for help here.

The only thing that comes to mind is different "compression" you get using different focal length (the more is your focal length the less is the distance between objects).

My main question is "could there be a need to own both?"

EOS Bodies / Re: Eos 1Dx and 5D mark III / 5 Dx tonight
« on: February 07, 2012, 11:44:56 AM »
... You can also spot a new model just by looking at the pixel dimensions.  Each sensor has different dimensions.  You might crop to 1D MK IV size, but it would be pointless...

1D X has the same image resolution as 7D.

I saw somewhere on forums 2 post-processed images of the same subject shot using 5D original and 400D and there was no difference at all. Nobody could tell what was the camera that was used for each of those.

EOS Bodies / Re: 1D X high res samples just appeared
« on: February 07, 2012, 08:24:35 AM »
Another thing that astonished me was that all sample shots were made at Auto WB setting. If you look on samples of other recently released models (Nikon's for example), you'll be able to see that WB of those was set manually to some XXXX Kelvin value.

If these 1D X examples are straight from the camera it means that it becomes much easier to handle colors and easier to post-process (or post-processing might be not even needed for some areas of photography). WB might have been configured in-camera though, as Canon's added some editing functions inside of it  :)

EOS Bodies / Re: 1D X high res samples just appeared
« on: February 07, 2012, 08:04:06 AM »
Check the second protrait's background noise, not as good as I expected.

the second one sucks.... it´s not very sharp either. not a good example imho.
Exactly~How come they can use this as the offical sample!! And the model is not as pretty as Nikon's  ;D ;D ;D ;D ;D

Here's a Nikon D4 image example shot at ISO 100 and it's not even close for me to those ISO 400 / 800 examples from 1D X taking into account look and feel of the images. I know it depends on personal taste, but I don't think ISO is the only thing we should pay attention to.

The ISO 1600 image is blurry and it looks like a shot with focus-error (may be front-focus due to recomposing after focus lock, for instance), however if you make it smaller it looks fine: resized sample of ISO 1600 shot and the grainy background even at 100% crop looks almost the same as in ISO 100 shot above made on D4.

EOS Bodies / Re: 1D X high res samples just appeared
« on: February 07, 2012, 05:07:02 AM »
It looks like all images are straight from the camera, shot in JPEG with WB set to Auto. Please correct me if I'm wrong.

EOS Bodies / 1D X high res samples just appeared
« on: February 07, 2012, 04:42:40 AM »

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