Z Family / Focus issues

Hello all! I'm a relative newbie... trying to get some experience in and build up a portfolio. I did a session for a good friend of mine and I keep running into focus issues. Wanted to share a few favorites and get any input. Thanks!

Oh, and this little boy was a challenge! He did NOT want to have his picture taken, so I was pleased to get a few good ones.

This was @ 1/125, 6.3, 400ISO

it might be a bad jpg conversion but most the shots look soft. maybe try a bigger aperture till you get the hang of things

Pixil Studio wrote in post #16826497
it might be a bad jpg conversion but most the shots look soft. maybe try a bigger aperture till you get the hang of things

Yea, that's my issue. Even up to 9 it's happening... Should I go bigger than that?

Hi

I dont think its the F stop, It seems as if the focusing is off.

1) Have you only used one lens? Is it the standard kit lens, also let us know the camera model, as their focussing systems vary, as well as methods of fine tuning.
2) What focussing method do you use? press halfway on shutter for beep on face and recompose?
3) what focal length you using? your shutter speed should be quick enough, unless you shooting at 150mm + without stabilisation.

I had to calibrate 2 of my lenses, as they were front focusing. Let me know the above 3 points and we can see what we can come up with.

what focal length were you using? Looks like camera shake. During bright daylight you should be able to use a much faster shutter speed.

First one would have been awesome.....if he was in focus. I have to ask the same questions as the posts above...what was your focal length, lens, camera, AF mode, etc.?

nazmo wrote in post #16826557
Hi

I dont think its the F stop, It seems as if the focusing is off.

1) Have you only used one lens? Is it the standard kit lens, also let us know the camera model, as their focussing systems vary, as well as methods of fine tuning.
2) What focussing method do you use? press halfway on shutter for beep on face and recompose?
3) what focal length you using? your shutter speed should be quick enough, unless you shooting at 150mm + without stabilisation.

I had to calibrate 2 of my lenses, as they were front focusing. Let me know the above 3 points and we can see what we can come up with.

1.This is with one lens. My kit lens crapped out, so this is with a sigma 70-300 on my 50D. I hope to save up for a better lens soon!

2.Yea, I press halfway, but I'm always afraid that's it's refocusing when I recompose. Maybe I need to understand how the auto focus mechanism works. I also notice different lights light up when I press to focus multiple times? Not sure what any of that means.

3. These are mostly at 70mm. I'm usually backing up as far as possible to get the frame I want. It actually seems to focus better the more I zoom in.

wait, so it focuses better when you zoom in yet you are using it mostly at 70 where it is the most zoomed out?

smaeda wrote in post #16826691
wait, so it focuses better when you zoom in yet you are using it mostly at 70 where it is the most zoomed out?

I usually can't back up far enough to have to zoom in! Limitations of space.

I think also maybe because when I'm zoomed in, it's for a close up and it's easier to focus on the face? Maybe I just need more practice.

PS. your 70-300mm is effectively 100mm to 400mm on your body... which is pretty long yes, you will back up quite a bit if you dont want to be cropped tightly.

You mention that you afraid of it refocussing, it wont ever, if you hear the beep and keep it depressed lose focus.
I suggest you just practice, maybe around your house, find a few items that are different distances and practice focusing and repositioning. like a chair placed mid way between a fence and some bushes. See if you end up with same results.

The image compression isnt too great in these posted images, so hard to tell, but it does feel as if its focussing on the center of the image, like image 1 - the shirt seems in better focus than the face. Image 2, the book is in better focus than the faces as well.

This will happen if you just press the shutter down without prefocussing, it will lock onto the centre point.

Just a comment, your framing, composition and lighting is good actually, its really just the focusing thats a challenge.

LeanneC wrote in post #16826669
1.This is with one lens. My kit lens crapped out, so this is with a sigma 70-300 on my 50D. I hope to save up for a better lens soon!

2.Yea, I press halfway, but I'm always afraid that's it's refocusing when I recompose. Maybe I need to understand how the auto focus mechanism works. I also notice different lights light up when I press to focus multiple times? Not sure what any of that means.

3. These are mostly at 70mm. I'm usually backing up as far as possible to get the frame I want. It actually seems to focus better the more I zoom in.

2. It may be refocusing when you recompose depending on what AF mode are you in. Are you shooting in ONE SHOT or AI SERVO? Also, when you press the shutter half way to focus are you releasing it at that point to recompose then repressing the shutter to take the shot or are you holding it down half way while recomposing then depressing it fully to take the shot? The different lights you're seeing (I'm assuming through the viewfinder) are your AF pioints activating. This brings up another question, are you using the center AF point only or are you letting the camera decide which AF point to use? If only 1 of those points is lighting up then you're using a single point. If all of them light up when you focus then the camera is picking which one to use but you have to understand that it will be "looking" for the part of the frame that has the most contrast and will focus on that (that may not always be the face/eyes).

3. This is leading me to believe your having the camera pick the AF point. When you use the longer focal lengths you fill more of those AF point with more of your subject and that gives your camera more of a chance to focus on what you want it to focus on.

I think Rivas hit the nail on the head.
I suggest you check your focus method, if its AI servo, it will constantly change focus area while you moving the camera or repositioning.
Single shot, single AF is the best option. It should be the default center one UNLESS you manually adjust and change it.

Assuming that you do have a fast enough shutter speed for the aperture.

This lens is an EF lens on a cropped (aps-c, ef-s) body. This means to find the actual focal length we have to do some math.1.6 x the focal length. If in this instance you are shooting at 70mm, 1.6 x 70mm = 112mm actual focal length. This means that a minimum shutter speed should be 1/125s if hand held, though IS will help in this area.

You may have a front or back focus issue.
What i look for next is to do a live view vs a standard shot and see which image has better focus.
What i mean by this is that when you shoot in live view, the camera uses phase detection rather than contrast detection to focus. A live view shot should be spot on while a standard one shot image taken my not be as sharp due to lens/body focus issues. Use a tripod with a fairly still subject to test a live view shot vs a standard shot. Try multiple images and subjects and compare them.

If the live view shot is sharper, you may have a micro focus lens issue. Which is more common on after market lenses than with canon lenses, but it scan be easily fixed.

I am mentioning this since the focus seems to be off on all of your images.

This link will tell you how to adjust your body to the lens http://www.fredmiranda​.com …/topic/1187247/​0#11321305

Micro5797 wrote in post #16826737
This lens is an EF lens on a cropped (aps-c, ef-s) body. This means to find the actual focal length we have to do some math.1.6 x the focal length. If in this instance you are shooting at 70mm, 1.6 x 70mm = 112mm actual focal length. This means that a minimum shutter speed should be 1/125s if hand held, though IS will help in this area.

Not true. The focal length is 70mm. The effective field of view is 112mm, but the focal length is still 70mm. I still agree, though, with the rest of your statement that this means you have to speed up the shutter to compensate for the 112mm FOV. One of the joys of using a APS-C sensor.....you have to do more math.