Struggling with focus

Silver Simon

Silver Simon

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Simon
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I posted some shots in the sports section and Gramps commented they look a tad soft. I agree and it is one of the many aspects of photography I am really struggling with, getting subjects in focus that are moving towards me.

Here are a couple and I would love to know what camera settings I should use.

poole1.jpg


poole29.jpg


I was using Manual select Single point AF and Spot metering.
I varied shutter speed from 1/600 down to 1/80 for panning.
I shot in MRaw and Mjpeg.

Help please guys. :)
 
I could be wrong but the back light of that white estate car looks in focus.

According to the EXIF data the shutter speed was 1/800 at f13, focal length 70mm
 
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It may help to understand how the AF system on a camera works. In the case of an object moving directly towards the camera, the focus system has to predict where the object will be at the moment the sensor is exposed. It does this by extrapolation of the speed it detects whilst the focus button is held down in AI focus mode.

Therefore, to give yourself and the camera the best chance, it is best to set the drive mode to continuous and take a series of frames as the object moves towards you. Even then, it is unlikely all of the frames will be sharp, but some almost certainly will be, depending on you other settings.

This is a greatly simplified explanation, but it may assist you.
 
Any filter fitted?
Lens hood used?
Lens spotless - have you checked?
How much of a crop?
Are these from the raws or the JPEGs? How were they processed - which software, what settings for picture style and/or sharpening?
Which AF mode?
Which AF pattern?
Where does the active AF point or points appear within the frame?
How long did you AF track the subject for before releasing the shutter?
 
Yellowbelly said:
It may help to understand how the AF system on a camera works. In the case of an object moving directly towards the camera, the focus system has to predict where the object will be at the moment the sensor is exposed. It does this by extrapolation of the speed it detects whilst the focus button is held down in AI focus mode.

Therefore, to give yourself and the camera the best chance, it is best to set the drive mode to continuous and take a series of frames as the object moves towards you. Even then, it is unlikely all of the frames will be sharp, but some almost certainly will be, depending on you other settings.

This is a greatly simplified explanation, but it may assist you.
Click to expand...

That's a great help thanks

tdodd said:
Any filter fitted? No
Lens hood used? Yes
Lens spotless - have you checked? Lens was clean.
How much of a crop? Not too much, these were taken with my 70-200
Are these from the raws or the JPEGs? How were they processed - which software, what settings for picture style and/or sharpening? RAW, photoshop
Which AF mode? Manual select Single point
Which AF pattern? Spot metering.
Where does the active AF point or points appear within the frame? In the centre
How long did you AF track the subject for before releasing the shutter? Only a second or two, not long.
Click to expand...
 
Answers all seem to be what I would hope for, but a little more clarification....

When I mentioned AF mode I meant One Shot, AI Focus or AI Servo?

Regarding placement of the point within the frame, since you've cropped these WE don't know where the centre of the frame was at the moment the shutter was released. It may have been on the background for all we know.

I don't use Photoshop, so I'm not acquainted with the options available for sharpening, but maybe you need to be more aggressive, and certainly apply some further sharpening as the final step after resizing the images. On defaults I think PS will only apply basic "capture" sharpening, which probably is not enough for the 7D.

Oh, and IS on or off? At these shutter speeds and with these subjects I'd advise turning it off.

If you're willing to upload/share one of your raw files somewhere maybe people will be able to find an answer.
 
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tdodd said:
Answers all seem to be what I would hope for, but a little more clarification....

When I mentioned AF mode I meant One Shot, AI Focus or AI Servo?

Regarding placement of the point within the frame, since you've cropped these WE don't know where the centre of the frame was at the moment the shutter was released. It may have been on the background for all we know.

I don't use Photoshop, so I'm not acquainted with the options available for sharpening, but maybe you need to be more aggressive, and certainly apply some further sharpening as the final step after resizing the images. On defaults I think PS will only apply basic "capture" sharpening, which probably is not enough for the 7D.

Oh, and IS on or off? At these shutter speeds and with these subjects I'd advise turning it off.

If you're willing to upload/share one of your raw files somewhere maybe people will be able to find an answer.
Click to expand...

I had it on one shot. I didn't use AI servo as I thought I knew where the bikes were going to go, so I could track them unlike a bird flying off a branch that could go in any direction.

The IS was on. I've been told it should always be on unless securely clamped to a tripod. You obviously think differently.

I will upload the RAW later.

Many thanks for your input, I really appreciate you taking the time and effort to help me. :thumbs:
 
Simon, I have re-read my explanation and it contains an error. The end of my second line should read AI servo.

Apologies.

However, from your last post it seems you were not using AI servo, and that I reckon is your main error.
 
Yellowbelly said:
Simon, I have re-read my explanation and it contains an error. The end of my second line should read AI servo.

Apologies.

However, from your last post it seems you were not using AI servo, and that I reckon is your main error.
Click to expand...

Thanks. I think you could well be right.

They are back racing at Poole next weekend so if I can I'll pop down and try again.
 
Hope you don't mind my 2p worth here. The way I've read this, you appear to have half pressed the shutter before the bikes arrived, then clicked the rest of the way when they came into shot. That's why the car is in focus - 'one shot' focuses at the half press point and doesn't change if something else enters the frame. As has been said already - AI Servo is the way to go.:thumbs:
 
Good luck. Post some of your shots afterwards.
 
FourRingCircus said:
Hope you don't mind my 2p worth here. The way I've read this, you appear to have half pressed the shutter before the bikes arrived, then clicked the rest of the way when they came into shot. That's why the car is in focus - 'one shot' focuses at the half press point and doesn't change if something else enters the frame. As has been said already - AI Servo is the way to go.:thumbs:
Click to expand...

Heck no, the more the merrier! :D

Thanks.
 
As a secondary method and if you are trying to catch them at the same spot you could use zone focusing as you have quite a good size zone to play with at f13. Pre focus to the spot the riders will be in and wait.
 
ernesto said:
As a secondary method and if you are trying to catch them at the same spot you could use zone focusing as you have quite a good size zone to play with at f13. Pre focus to the spot the riders will be in and wait.
Click to expand...

I actually tried that!!! :D

I have to say here, my eyesight is not as good as it was. I find it difficult at times in Manual focus mode to get a pin sharp focus point, even with the dio wheel turned to max.

Is there a clip on replacement viewfinder with a stronger correction available?
 
Canon do supply correction viewfinder lenses for that very purpose.
 
Silver Simon said:
I had it on one shot. I didn't use AI servo as I thought I knew where the bikes were going to go, so I could track them unlike a bird flying off a branch that could go in any direction.
Click to expand...
Kerching! One Shot for an approaching subject - tricky to pull off unless you pre-focus at the required distance and then wait for the subject to reach that distance. You may know where the bikes were going, but the camera hasn't got a clue. With AI Servo it would be able to predict their distance at the moment you released the shutter.

Silver Simon said:
The IS was on. I've been told it should always be on unless securely clamped to a tripod. You obviously think differently.
Click to expand...
The objective of IS is to stabilise the lens. You have panning mode, useful for subjects moving steadily across the frame or up/down the frame, but this mode is not suitable for compound movements like diagonal motion or random movements to follow an erratic subject. At 1/800 with a 200mm lens there is no need in the first place and, given the prospect that it would only attempt to fight your deliberate movements of the lens, actually quite counter-productive. At least that is my experience when shooting BIF with my 100-400.

Silver Simon said:
I will upload the RAW later.
Click to expand...
I think now we already have the answer. One Shot is probably the biggest issue. IS may or may not be a factor too.
Silver Simon said:
Many thanks for your input, I really appreciate you taking the time and effort to help me. :thumbs:
Click to expand...
No problem. :)
 
I'm hoping to go to a cycling event at the weekend, so a lot of useful information here.

To my untrained eye, the picture looks fine (I'm sure someone will tell me its not :))

It just looks like it could do with some sharpening, my attempt is below.

I'm new to all this so could be way of the mark :shrug::)

 
At 100% it's actually not bad, but a bit more of a whack with the sharpening stick and a contrast boost might help it along. Here's my take....

20120815_112006__LR.jpg
 
gramps said:
It can be improved a lot but better to get it right from the camera.
Click to expand...
WOW! That looks soooooooooo much sharper than my attempts. You've even got the rider's face on the left sharp and he was a total blur! :) I think another thing I've learned in this thread is I need to research Photoshop a lot more!

Thanks.
tdodd said:
At 100% it's actually not bad, but a bit more of a whack with the sharpening stick and a contrast boost might help it along. Here's my take....
Click to expand...

Tim, yours doesn't look quite as sharp as Gramps, however you seemed to have kept more of the focus on the central rider.

Thanks also.
 
Your focus was only on the central rider. I considered it a deliberate artistic wish to place emphasis on him as "the subject". Other elements within the scene helped to provide context and create a story, but they were OOF and, in my opinion, should not have been sharpened in an effort to salvage them. If anything they should have been blurred further (or left alone) in order to strengthen the emphasis on the primary subject.

I can't see any point in shooting stuff soft/OOF and then trying to sharpen it back again. If you want it sharp then shoot it sharp, and enhance it (sharpen it further) if need be. If you want it soft then shoot it soft and let it be or soften it further.

Oh, and again in my opinion, sharpening should be applied only so far as to make things look "naturally" sharp, as the eye might see them in real life, and not oversharpened with ugly halos and other artefacts which serve only to make the whole effort look decidedly amateur (polite term).
 
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tdodd said:
Your focus was only on the central rider. I considered it a deliberate artistic wish to place emphasis on him as "the subject". Other elements within the scene helped to provide context and create a story, but they were OOF and, in my opinion, should not have been sharpened in an effort to salvage them. If anything they should have been blurred further (or left alone) in order to strengthen the emphasis on the primary subject.

I can't see any point in shooting stuff soft/OOF and then trying to sharpen it back again. If you want it sharp then shoot it sharp, and enhance it (sharpen it further) if need be. If you want it soft then shoot it soft and let it be or soften it further.
Click to expand...

Tim,

You are spot on, that is exactly what I was trying to do put the attention on the central rider. Same as this one ...
poole8.jpg


I was just amazed that something as blurred (on purpose) could be made as sharp. :)
 
A general question: when using BF in this situation (with Nikon equivalent of servo) do you release the BB just before releasing the shutter or keep it held down?
 
MJWC1 said:
A general question: when using BF in this situation (with Nikon equivalent of servo) do you release the BB just before releasing the shutter or keep it held down?
Click to expand...

Sorry what's the BB? Mr newbie here! :)
 
FourRingCircus said:
Hope you don't mind my 2p worth here. The way I've read this, you appear to have half pressed the shutter before the bikes arrived, then clicked the rest of the way when they came into shot. That's why the car is in focus - 'one shot' focuses at the half press point and doesn't change if something else enters the frame. As has been said already - AI Servo is the way to go.:thumbs:
Click to expand...

^^ for me
it's been said a few different ways but I would also open up the aperture as much as possible, freezing the action might not be as good for a shot but it will show more easily where you are focused.
then you can reduce the aperture to bring more of the shot into focus
and also introduce some motion in the wheels etc if that's what you're looking for
on the 7D also I would use the centre cluster of auto focus points.
the 7D has a decent AF system ( I hope so anyway as I've just bought one!) and using centre point focusing negates this I feel. use the cluster and let the camera work for you.
I might be wrong but that's what I'd try
 
You keep the button pushed throughout shooting. You should ideally pick up the subject early - say for one second or more before releasing the shutter - so that the camera can work out the speed and direction of subject movement and start to track it accurately. Then you keep focusing/tracking continuously while shooting. The camera should work out the timing for things like shutter lag and keep the lens focused to the anticipated subject position for the moment of shutter release. If you stop pressing the AF button then the camera will stop following the subject. Put it another way - if you were using the shutter button for focusing instead of the back button then the camera would still be focusing when you released the shutter.

To release the button before shooting would leave you in a situation much like shooting in One Shot or Single mode. The camera will have focused, but by the time the shutter fires it will be focused in the wrong place. This may not matter much with a generous DOF, but when shooting wide open with a fast lens and less margin for error you need to keep all your ducks in a row. AF systems face enough of a challenge as it is without the operator picking the wrong mode or stopping using them altogether. :thinking:

Take a look at this page and scroll down a bit to the flash sequence (third example down the page) of 20 images and you will see how AI Servo (Continuous) AF should follow a moving subject while you shoot. It can't very well do that if you have stopped focusing.

http://robgalbraith.com/bins/multi_page.asp?cid=7-8740-9068
 
tdodd said:
You keep the button pushed throughout shooting. You should ideally pick up the subject early - say for one second or more before releasing the shutter - so that the camera can work out the speed and direction of subject movement and start to track it accurately. Then you keep focusing/tracking continuously while shooting. The camera should work out the timing for things like shutter lag and keep the lens focused to the anticipated subject position for the moment of shutter release. If you stop pressing the AF button then the camera will stop following the subject. Put it another way - if you were using the shutter button for focusing instead of the back button then the camera would still be focusing when you released the shutter.

To release the button before shooting would leave you in a situation much like shooting in One Shot or Single mode. The camera will have focused, but by the time the shutter fires it will be focused in the wrong place. This may not matter much with a generous DOF, but when shooting wide open with a fast lens and less margin for error you need to keep all your ducks in a row. AF systems face enough of a challenge as it is without the operator picking the wrong mode or stopping using them altogether. :thinking:

Take a look at this page and scroll down a bit to the flash sequence (third example down the page) of 20 images and you will see how AI Servo (Continuous) AF should follow a moving subject while you shoot. It can't very well do that if you have stopped focusing.

http://robgalbraith.com/bins/multi_page.asp?cid=7-8740-9068
Click to expand...

Thank you again, BOOB number 6 sorted. I'm pretty sure I don't keep it pressed, hence why some shots (not posted) are totally wrong. :)
 
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