what am I doing wrong?

Cocohoney

Cocohoney

Messages
178
Name
Alexandra
Edit My Images
Yes
When I take photographs of the children at a bit of a distance I simple cannot manage to get them in focus, I always seem to somehow manage to focus on the background. It isn't motion blur- I am definitely incorrectly focusing.

It only happens when they are a good distance away and filling a very small part of my view- as in they do not fill the rectangle that pops up around the focal point.

I have tried only using the centre point to focus and not recomposing in case I was moving when doing this. I am sure this is not what is happening. I am pointing the focal point at my child, and however far behind the background is, it is that which is in focus.

I know it is operator error, as when they are closer I get lovely sharp pictures, but it is almost as if they aren't there in the distance ones!

How can I rectify this? What am I doing wrong?
Cocohoney is online now This user allows their images to be edited and reposted (on these forums only) Cocohoney's Gallery Edit/Delete Message
 
What camera and lens are you using?

Have you set a focus mode that continually adjusts the focus as the subject moves? On Canon systems this is called AI Servo.
 
A Nikon D90 and 35mm 1.8.

I have just tried today the 3D focus mode, I think that might be it? but this only seems available if I put the camera in sports setting I think- I will go back to the manula i think. I am not sure if it helped really, started raining hard so only took a couple in a rush before giving up, bit dark so some motion blur to the children anyway.

The thing is it does only happen when the subject is smaller than the focal area, I need to understand how to focus on something so small- I can never seem to see in my viewfinder that it is out of focus in order to do it manually, it's just too small for my poor eyes!
 
If you are shooting at f/1.8 then your working depth of field will be quite narrow - you have to focus on exactly the right place and if you or the subject moves at all then it can easily go wrong...
 
no I was shooting at 5.6

I have tried with a stationary subject too- it is definitely the size of the subject within the frame that is the issue, the problem is I can't tell until I zoom right in that has happened and by then I have missed the shot.
I have tried very hard to make certain I am holding that focus point directly over the subject as its a problem that has been making me grrrrrrr for a while.
I am obviously doing something wrong, or have set my camera wrongly for what I am asking it to do as it just doesn't 'see' the subject, only what is directly past it.
I have just read that the focal point is wider than the centre spot, does ii extend to or past the rectangle around it? If so then how do you make sure you are focusing on something small in you frame when using af?
The same post says it can be that af can be more sensitive to one side and suggests testing that so you can at least be aware of it.
I wonder if this is the case as I have noticed that on occasion when I take a face on an agle and focus on the nearest eye, the furthest one is in focus.
 
Not sure about Nikon but a Canon focus points cover an area a bit outside the squares that you see in the viewfinder. Whilst you might know what in that tiny square is important, the camera doesn't it is just looking for something contrasty within the area it's working with, so I think you are expecting something the camera can't deliver. One point that puzzles me is why if the children are the subject that you want in focus are they such a small item in the viewfinder.
 
With the nikon software open the file and just double check where the focus point actually is.

Best wishes
Cliff
 
I will trythe Nikon software- I didn't realise you could do that, thank you.

They are only small in the frame as they were in front of a lovely building, or sledging, or in a large group, or cycling, or in amongst some blubells etc
I guess perhaps I should be closing down my aperture more, I know that would give me more space for error, but I didn't feel that was the problem and I need the speed- I suppose if possible I could focus instead on something in the same plane as the subject and recompose, but I'm not always fast enough!

Any ideas for testing what area the focal point is covering?
 
Or up the iso to allow a smaller aperture and get a bigger DOF without sacrificing shutter speed, check the focus point to eliminate that first because if it is slightly off your intended focus point it may put the intended subject out of the DOF range

Atb
Cliff
 
why not use centre point focus and recompose, think we need pics as its surmising :thumbs: i cant really comment on your prob as its Nikon which I have never use or wish to
 
Just Dave said:
why not use centre point focus and recompose, think we need pics as its surmising :thumbs: i cant really comment on your prob as its Nikon which I have never use or wish to
Click to expand...

Bit harsh Dave! :lol:
 
Cocohoney said:
Any ideas for testing what area the focal point is covering?
Click to expand...

Yep, I tested the size/shape of my focus point by taking shots of thin twigs in the garden at distance, preferably with something beyond it which it'd focus on if it missed the twig. You soon work out how accurate you have to be with the focus point.
 
I think it's a little bit of the wrong technique being used for the expected result.

A standard lens used with a wide aperture, fairly close up will allow you to use focus to separate the subject from the surroundings. But if your subject is small in the viewfinder, then you're clearly wanting to show the surroundings too, so you'll need to stop down and your focus won't be so critical.
 
NigelPaul said:
Bit harsh Dave! :lol:
Click to expand...

:D

Phil V said:
I think it's a little bit of the wrong technique being used for the expected result.

A standard lens used with a wide aperture, fairly close up will allow you to use focus to separate the subject from the surroundings. But if your subject is small in the viewfinder, then you're clearly wanting to show the surroundings too, so you'll need to stop down and your focus won't be so critical.
Click to expand...

agree Phil, could be aperture as well, I think we need to see a shot at least as were all just surmising
 
Cocohoney said:
It only happens when they are a good distance away and filling a very small part of my view- as in they do not fill the rectangle that pops up around the focal point.
Click to expand...

Well if this is right http://www.google.co.uk/imgres?q=D90+and+35mm+1.8+centre+focus+point&um=1&hl=en&safe=off&biw=1680&bih=904&tbm=isch&tbnid=NfJOBT2qBlZBCM:&imgrefurl=http://www.digitalreview.ca/content/Canon-Rebel-T2i-EOS-550D-Compared-to-Nikon-D90.shtml&docid=0G8ICE7YBn2RwM&imgurl=http://www.digitalreview.ca/pics/D90/D90_T1i_AF_points.jpg&w=671&h=168&ei=b7VAT8mjKYGt0QWVwpGPDw&zoom=1&iact=hc&vpx=1082&vpy=615&dur=148&hovh=112&hovw=449&tx=246&ty=50&sig=111118370063052062481&page=6&tbnh=54&tbnw=216&start=173&ndsp=35&ved=0CIAHEK0DMMAB your subjucts must be quite a distance away if they do not fill the rectangle in your viewfinder :shrug: If they are on the move then you need to be able to track them and in the same direction they are going which I think at this distance is a bit much to expect by just firing a couple of shots off. As mentioned though unles you can post some pics up with exif intact and even a screengrab showing where the focus point/points locked on then it is all guess work.
 
Ok, how do I get them on here? Sorry for the lack of computer savvy! I have no idea if I can show where the focus points locked, I would really like to find that out to see if I am at least aiming where I think I am! I have been trying to find it on the Nikon software as mentioned before but can't.
I have photoshop- can I do it with that?

They are quite a distance away- one of the recent ones being four of them in a line at the top of a hill about to sledge down it, so yes, perhaps I am expecting too much and I just need to go with stopping it down and upping my iso. Also, I'm pretty sure I automatically aim for the head with my focal point which of course is pretty narrow and so the camera will just be looking to the sides of it if the background has good contrast then? I guess I had just assumed it would go for the thing in the centre really :shake:

Thanks for the replies.

WilliamC, thanks, I will try that today
 
Last edited:
Hmmm, looking at that link they do look very tiny don't they-I use normal too, not wide...but I do only have the 35mm at the moment, and I couldn't really get closer with the sledging one. I think it is a problem even if they do fill the rectangle though, but probably overlap it by not much, so could still be the same thing maybe?
 
With the subject so small in the frame, how do you see that it's not sharp? Are you cropping the image a lot?

I might be barking up the wrong tree as I don't know the relative size of the focus rectangle in your view finder. But my first thought is that you need a longer lens, or to bring the subject closer.
 
Alastair said:
With the subject so small in the frame, how do you see that it's not sharp? Are you cropping the image a lot?

I might be barking up the wrong tree as I don't know the relative size of the focus rectangle in your view finder. But my first thought is that you need a longer lens, or to bring the subject closer.
Click to expand...

I thought this when reading the thread earlier. If your cropping a lot, which is how I read your first few posts, then you will loose a lot of detail as you crop in.

Maybe i`m reading it wrong though.
 
Yes, I think I am probably looking too closely. I only have the 35mm at the moment as I am switching over to Canon and have got rid of my other lenses to help fund this. I suppose I hadn't used this lens for shots like that before and was eaking them from much further away than I usually would have done.
It's just that when I zoom in it is very very obviously focused on whatever is behind it, and if this is a distance away, it does make a difference to how sharp the image looks, even when I zoom back out.
Am I guilty of too much pixel hunting then? Perhaps it isn't something I should expect to be able to do. I have to go out now, but I will try to upload some pictures tomorrow so it isn't just speculation, hopefully if I am doing something wrong other than just being too far away, you will be able to tell? I haven't been able to find the thing on the Nikon software which shows where the focus point is? Can I do this in photoshop/lightroom?
Thanks for all your replies and help, I'll be back tomorrow.
 
Ok, so today I went out walking with the dogs and took some test shots (please ignore lack of style!) to put on here.
I still can't find how to get where my focus fell to show, so I used the centre point and did not recompose. I took them in RAW. I have put a red line around whatever I was aiming at (obviously this is the middle, but I just wanted to show which bit I felt I had pointed at), and I had to resize them to get them on here, but otherwise no processing.
Also I took two of a tape measure wide open and the centre point aiming at 15.

Could you all tell me what you think? Obviously I am doing something wrong as the focus is in the wrong place in all of these isn't it? Thanks for your help

DSC_7674.jpg


DSC_7673.jpg


DSC_7672-Edit.jpg


DSC_7681.jpg


DSC_7687.jpg


DSC_7682.jpg



sorry there are so many, 3 to follow.
 
Are they big enough to see? Do I need to put them on flickr and link from there to see them full size? I am not sure how visible it is here as I have had to make them smaller.
Gosh, all these questions- I don't usually come across this desperate :eek: :D
 
Last edited:
Oh, and I took these all on av, the first 6 f3.5, the last dog one f7.1

the tape measures are at f1.8
 
Thise examples look ok, but they don't really relate to the original problem though..
 
To start with I thought it looked like the lens might be front focusing a little, then the low aperture shots look like they are rear focusing a little but at that distance and aperture it could easily be camera movement. Also at these picture sizes it can be difficult to tell, 100% crops would help (just crop out a small bit so that when you post it at forum size it is at its full size).

Do you have a tripod?

If so set up some test shots with the side of a cereal packet and then try focusing normally and then using live view. Live view focuses differently and usually more accurately (but it takes much longer).
 
No, not all of them, but I aimed for the dogs' legs specifically because it didn't fill the central focal point rectangle.
I don't know if you can see on these but when you zoom in the leg or grass behind is more in focus than the one I pointed at I think?
The dog's eye too, doesn't seem to be in focus, but the top of his nose is? How am I missing that sharpness where I try to get it?

I only did the tape measure as I read about it being a test to see where you were focusing? Does that look ok to you then? I thought I had missed the 15 and gone slightly behind? Am I looking too close.
 
Ah ok, so crop around where I wanted the focus to be? I will try to do that later-I am at work at the moment.

I can borrow a tripod later in the week- do I take the cereal packet at an angle and focus on the corner, taking pictures focused normally and with live view? I don't have a remote but I could do it on the timer...

Do youthink I might be moving as I am taking the shot? I did wonder this and I have tried to work on making sure I am well rooted and holding the camera firmly, any tips for improving this?

Thanks for the help
 
What you do is take a picture of the cereal packet straight on but lie a ruler along the table with, say, 15cm being level with the packet edge. That way you can focus on something flat to minimise any mis-focussing but also see if the lens is front of back focusing.

There could well be an issue with the lens but to be honest, 99 times out of 100 it is the user. The problem is that once you get in your head that your kit is at fault it is hard to dismiss - that is why a tripod test is good :)
 
If there's a trend, it looks to me to be a bit of back-focus. Could be you, or camera, or lens.

If it's you, and you have a tendency to move or lean forward a little after focusing, it will vary and come and go. If it's camera, it will always appear. If it's lens, it will not show up when you change lenses. BTW, if your software can show the AF point, bear in mind this only shows which AF point was used, not necessarily where it was when you focused. If you use focus-recompose technique for example, by definition it won't of course. And if there's any delay between focusing and shooting then errors can creep in.

To check you camera/lens, try this test. It's very easy and very accurate, provided you set the camera up square to the box, on a tripod, so there is no possibility of it focusing on any other distance (AF points are larger than shown in the viewfinder).

Use centre AF point on the face of the box, and then the rule will indicate where the focus has actually landed. Keep the distance sensible, like a few feet away, so the frame is the equivalent of about three boxes wide, if you see what I mean. Shoot at lowest f/number.

IMG_3381-1.jpg
 
Brilliant, thanks for the explanations guys, I will do that hopefully Friday

I didn't notice this happening with my other lenses I don't think, but I don't have them any more anyway to test with. I wasn't thinking it was the lens, I have taken the childrens faces up close front on that are lovely and sharp, so I had thought it was something I was doing to 'miss' when a more precise focus point was required.

I have been trying to be more aware of my stance, what can I do to make sure I don't shift? I am feeling a bit hopeless, I love taking photos and this is so frustrating!
 
Cocohoney said:
Brilliant, thanks for the explanations guys, I will do that hopefully Friday

I didn't notice this happening with my other lenses I don't think, but I don't have them any more anyway to test with. I wasn't thinking it was the lens, I have taken the childrens faces up close front on that are lovely and sharp, so I had thought it was something I was doing to 'miss' when a more precise focus point was required.

I have been trying to be more aware of my stance, what can I do to make sure I don't shift? I am feeling a bit hopeless, I love taking photos and this is so frustrating!
Click to expand...

You could try standing still! But joking aside, that won't help if the subject is moving.

I tend to use centre-point only, and focus-recompose technique mostly, with back-button AF. With moving subjects, I might check and recheck the focus once a second. If it needs more frequently than that, switch to servo but that can be more trouble than it's worth unless you can nail the AF point exactly all the time, as it will constantly shift focus, even when you don't want it to. Servo and back-button AF can give you more control.

If the camera/lens is fine, then it's just a matter of practise :)
 
HoppyUK said:
You could try standing still! But joking aside, that won't help if the subject is moving.
Click to expand...

I'll give it a go :D

I have only read a little about back button AF, isn't it mostly used for sports/action shots? Would it be useful to me?

If answering please bear in mind that I still have trouble rubbing my tummy and patting my head...
 
Cocohoney said:
I'll give it a go :D

I have only read a little about back button AF, isn't it mostly used for sports/action shots? Would it be useful to me?

If answering please bear in mind that I still have trouble rubbing my tummy and patting my head...
Click to expand...

I think most cameras have the option of back-button AF (under your thumb) as opposed to focusing when you half press the shutter release.

It just separates focusing from exposure metering and shooting. Most folks that try it seem to stick with it.

For example, if you're in servo tracking mode, as I said this can be a PITA as when you're framing up a shot, or waiting for the moment, focus will shift around according to where the AF point is. You only have to slip for a moment and it will go straight to the background which is very irritating.

With back-button, you can engage servo as and when you like, and hold it on, or off, as you like. It quickly becomes natural. But there's no doubt that accurate AF, on moving subjects when depth of field is slender, takes a bit of practise. With fast moving subjects it also asks a lot of both the camera and the lens, and higher grade kit is better at it.
 
You must log in or register to reply here.
Back
Top