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A question of focus

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Chupacabra

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I've been struggling with the focus issues on my G2 almost since I bought it. I've gotten some good and but a lot of bad pictures. I know this question has been beaten absolutley to death in this forum, but I noticed something interesting today. I was photographing protestors at a symposium my college was hosting, and was very unhappy with some of the crowd shots I got. But I then realized that every one of the pictures I had taken of demonstrators with portrait mode had come out wonderfully sharp, but many ones taken in AUTO mode or the mode just below auto (can't remember the name- designed for quickly shooting scenes with a large DOF without zoom) were unsharp and generally out of focus. Out of 70 shots in portrait mode, not one was blurry. Out of 30 or 40 in auto, 1/3 are blurry. Is there any explaination for this? What's the deal?

Shot in portrait mode and about half way between wide angle and telefoto:



Shot in auto mode- I think there was enough there for the camera to lock onto focus. Too much maybe?

 
Please post aperture and shutter speed on the problem photo.

Morris
Chupacabra said:
I've been struggling with the focus issues on my G2 almost since I
bought it. I've gotten some good and but a lot of bad pictures. I
know this question has been beaten absolutley to death in this
forum, but I noticed something interesting today. I was
photographing protestors at a symposium my college was hosting, and
was very unhappy with some of the crowd shots I got. But I then
realized that every one of the pictures I had taken of
demonstrators with portrait mode had come out wonderfully sharp,
but many ones taken in AUTO mode or the mode just below auto (can't
remember the name- designed for quickly shooting scenes with a
large DOF without zoom) were unsharp and generally out of focus.
Out of 70 shots in portrait mode, not one was blurry. Out of 30 or
40 in auto, 1/3 are blurry. Is there any explaination for this?
What's the deal?

Shot in portrait mode and about half way between wide angle and
telefoto:



Shot in auto mode- I think there was enough there for the camera to
lock onto focus. Too much maybe?

Click to expand...
 
  1. 1: 1/400s f/2.5 at 16.8mm (35mm equivalent: 193mm)
  1. 2: 1/200s f/2.2 at 12.5mm (35mm equivalent: 63mm)
The shutter speed on #2 is slower, but I don't think it's slow enough to account for the camera blur. Interestingly, it is on a very small f stop considering the type of shot it is.
 
I think the first picture is great, very interesting in what's happening, the whole composition is great, the colors are nice and the focus seems just fine, great shot.

The second one is odd in that I can't see anything in focus.... except, perhaps, the blue sweater arm at the very far, far right of the pic? Is it possible it just blew it and picked 2m and with such a narrow DOF at f2.whatever you had that only that very close subject is in focus? What does the EXIF data say for subject distance?

--
Eric
Disclaimer: Snapshooter, and proud of it ;-)
http://www.pbase.com/haglunde
Chupacabra said:
I've been struggling with the focus issues on my G2 almost since I
bought it. I've gotten some good and but a lot of bad pictures. I
know this question has been beaten absolutley to death in this
forum, but I noticed something interesting today. I was
photographing protestors at a symposium my college was hosting, and
was very unhappy with some of the crowd shots I got. But I then
realized that every one of the pictures I had taken of
demonstrators with portrait mode had come out wonderfully sharp,
but many ones taken in AUTO mode or the mode just below auto (can't
remember the name- designed for quickly shooting scenes with a
large DOF without zoom) were unsharp and generally out of focus.
Out of 70 shots in portrait mode, not one was blurry. Out of 30 or
40 in auto, 1/3 are blurry. Is there any explaination for this?
What's the deal?

Shot in portrait mode and about half way between wide angle and
telefoto:



Shot in auto mode- I think there was enough there for the camera to
lock onto focus. Too much maybe?

Click to expand...
 
You have touched on a very interesting subject, but are you really comparing apples with apples?

In the uppermost photo, the pane of focus appears to be about 6 feet from the camera lens. The 2 women standing alone are both out of focus :(

In the 2nd photo, everything beyond the 6 foot mark appears to be out of focus - or is it just me?
Chupacabra said:
I've been struggling with the focus issues on my G2 almost since I
bought it. I've gotten some good and but a lot of bad pictures. I
know this question has been beaten absolutley to death in this
forum, but I noticed something interesting today. I was
photographing protestors at a symposium my college was hosting, and
was very unhappy with some of the crowd shots I got. But I then
realized that every one of the pictures I had taken of
demonstrators with portrait mode had come out wonderfully sharp,
but many ones taken in AUTO mode or the mode just below auto (can't
remember the name- designed for quickly shooting scenes with a
large DOF without zoom) were unsharp and generally out of focus.
Out of 70 shots in portrait mode, not one was blurry. Out of 30 or
40 in auto, 1/3 are blurry. Is there any explaination for this?
What's the deal?

Shot in portrait mode and about half way between wide angle and
telefoto:



Shot in auto mode- I think there was enough there for the camera to
lock onto focus. Too much maybe?

Click to expand...
--
Zippity - A happy G2 owner
http://www.pbase.com/zippity/profile
Wellington, New Zealand
 
Ah, now that I have the exposure data I understand the problems. I don’t know why the camera chose such a wide aperture. The limited depth of field combined with contrast focusing has caused your problem.

The autofocus system uses contrast to focus. The camera found a high contrast object in the foreground, the white rope agents the green grass, and focused on it. Many prosumer digicams do this and it is very frustrating. You have to learn to watch out for this situation and lock the focus and then compose when this happens. If the G2 had a better manual focus system I would suggest it, but frankly manual focus is not what it should be.

Morris
Chupacabra said:
I've been struggling with the focus issues on my G2 almost since I
bought it. I've gotten some good and but a lot of bad pictures. I
know this question has been beaten absolutley to death in this
forum, but I noticed something interesting today. I was
photographing protestors at a symposium my college was hosting, and
was very unhappy with some of the crowd shots I got. But I then
realized that every one of the pictures I had taken of
demonstrators with portrait mode had come out wonderfully sharp,
but many ones taken in AUTO mode or the mode just below auto (can't
remember the name- designed for quickly shooting scenes with a
large DOF without zoom) were unsharp and generally out of focus.
Out of 70 shots in portrait mode, not one was blurry. Out of 30 or
40 in auto, 1/3 are blurry. Is there any explaination for this?
What's the deal?

Shot in portrait mode and about half way between wide angle and
telefoto:



Shot in auto mode- I think there was enough there for the camera to
lock onto focus. Too much maybe?

Click to expand...
 
Chupacabra said:
  1. 1: 1/400s f/2.5 at 16.8mm (35mm equivalent: 193mm)
Click to expand...
Typo - you meant 94 mm (not 193).
Chupacabra said:
  1. 2: 1/200s f/2.2 at 12.5mm (35mm equivalent: 63mm)
The shutter speed on #2 is slower, but I don't think it's slow
enough to account for the camera blur. Interestingly, it is on a
very small f stop considering the type of shot it is.
Click to expand...
Its pretty clear from the flags and signs in #2 that it's overexposed. The slower shutter and wider aperture support this. If you checked the histogram display you'd see blown highlights flashing. Many of the complaints I've seen about G2 focus are due to overexposure. When you overexpose, you lose dynamic range, which reduces contrast and the impression of sharpness. Some of this contrast can be regained in software, but the blown highlights cannot.

In addition, any zoom lens will not be at its best when wide open. Your depth of field is also shallower at wide apertures. This is one case where you'd have been better off with a slower shutter speed, say 1/100 sec.

And finally, you may want to learn how to apply software sharpening. Hope this helps, GKL
 
That 193mm conversion was just what pbase spit out after reading the exif info. I'm fairly proficient in photoshop, so sharpening up most pictures is not a problem, but something like this is a pain. But I guess my question is why did the auto mode on the camera choose those settings if they would lead to a blurred image?
gkl said:
Chupacabra said:
  1. 1: 1/400s f/2.5 at 16.8mm (35mm equivalent: 193mm)
Click to expand...
Typo - you meant 94 mm (not 193).
gkl said:
  1. 2: 1/200s f/2.2 at 12.5mm (35mm equivalent: 63mm)
The shutter speed on #2 is slower, but I don't think it's slow
enough to account for the camera blur. Interestingly, it is on a
very small f stop considering the type of shot it is.
Click to expand...
Its pretty clear from the flags and signs in #2 that it's
overexposed. The slower shutter and wider aperture support this.
If you checked the histogram display you'd see blown highlights
flashing. Many of the complaints I've seen about G2 focus are due
to overexposure. When you overexpose, you lose dynamic range, which
reduces contrast and the impression of sharpness. Some of this
contrast can be regained in software, but the blown highlights
cannot.

In addition, any zoom lens will not be at its best when wide open.
Your depth of field is also shallower at wide apertures. This is
one case where you'd have been better off with a slower shutter
speed, say 1/100 sec.

And finally, you may want to learn how to apply software
sharpening. Hope this helps, GKL
Click to expand...
 
Zippity said:
You have touched on a very interesting subject, but are you really
comparing apples with apples?

In the uppermost photo, the pane of focus appears to be about 6
feet from the camera lens. The 2 women standing alone are both out
of focus :(
Click to expand...
I don't have a problem with this- I expected the portrait mode to create a shallow DOF. My problem is that in the second picture there just doesn't appear to be any focus at all. :(
 
My pbase directory is http://www.pbase.com/chupacabra . Where do I find subject distance in the exif data?
Eric Haglund said:
The second one is odd in that I can't see anything in focus....
except, perhaps, the blue sweater arm at the very far, far right of
the pic? Is it possible it just blew it and picked 2m and with such
a narrow DOF at f2.whatever you had that only that very close
subject is in focus? What does the EXIF data say for subject
distance?

--
Eric
Disclaimer: Snapshooter, and proud of it ;-)
http://www.pbase.com/haglunde
Chupacabra said:
I've been struggling with the focus issues on my G2 almost since I
bought it. I've gotten some good and but a lot of bad pictures. I
know this question has been beaten absolutley to death in this
forum, but I noticed something interesting today. I was
photographing protestors at a symposium my college was hosting, and
was very unhappy with some of the crowd shots I got. But I then
realized that every one of the pictures I had taken of
demonstrators with portrait mode had come out wonderfully sharp,
but many ones taken in AUTO mode or the mode just below auto (can't
remember the name- designed for quickly shooting scenes with a
large DOF without zoom) were unsharp and generally out of focus.
Out of 70 shots in portrait mode, not one was blurry. Out of 30 or
40 in auto, 1/3 are blurry. Is there any explaination for this?
What's the deal?

Shot in portrait mode and about half way between wide angle and
telefoto:



Shot in auto mode- I think there was enough there for the camera to
lock onto focus. Too much maybe?

Click to expand...
Click to expand...
 
I agree with Morris and others. It looks like the focus square was on the girl in the green shirt, and may have picked up some of the metal post. This would place focus in the foreground and the shallow DOF (wide aperture) and overexposure did the damage. This is why I generally use Av mode. GKL
 
There seems to be a lot of subtleties concerning the AF on the G2. Has anybody made a post of collected tips on how to get it to shoot properly? I often run into the problem of having to frame a shot a certain way (like with landscapes)- if I meter on one place, focus might be right, but white balance would be off or the other way around.
morris said:
The autofocus system uses contrast to focus. The camera found a
high contrast object in the foreground, the white rope agents the
green grass, and focused on it. Many prosumer digicams do this and
it is very frustrating. You have to learn to watch out for this
situation and lock the focus and then compose when this happens.
If the G2 had a better manual focus system I would suggest it, but
frankly manual focus is not what it should be.

Morris
Chupacabra said:
I've been struggling with the focus issues on my G2 almost since I
bought it. I've gotten some good and but a lot of bad pictures. I
know this question has been beaten absolutley to death in this
forum, but I noticed something interesting today. I was
photographing protestors at a symposium my college was hosting, and
was very unhappy with some of the crowd shots I got. But I then
realized that every one of the pictures I had taken of
demonstrators with portrait mode had come out wonderfully sharp,
but many ones taken in AUTO mode or the mode just below auto (can't
remember the name- designed for quickly shooting scenes with a
large DOF without zoom) were unsharp and generally out of focus.
Out of 70 shots in portrait mode, not one was blurry. Out of 30 or
40 in auto, 1/3 are blurry. Is there any explaination for this?
What's the deal?

Shot in portrait mode and about half way between wide angle and
telefoto:



Shot in auto mode- I think there was enough there for the camera to
lock onto focus. Too much maybe?

Click to expand...
Click to expand...
 
I too am having problems with focus on the G2 - problems that I didn't have with my G1. I shot 100 photos today, just trying to get the same type of sharp clear photos I could get with my G1 - and got maybe 4 shots that are really in focus.

Unless I find something here tonight that changes my mind - I'm going to desperately try to find another G1 tomorrow and cut my losses.
Chupacabra said:
morris said:
The autofocus system uses contrast to focus. The camera found a
high contrast object in the foreground, the white rope agents the
green grass, and focused on it. Many prosumer digicams do this and
it is very frustrating. You have to learn to watch out for this
situation and lock the focus and then compose when this happens.
If the G2 had a better manual focus system I would suggest it, but
frankly manual focus is not what it should be.

Morris
Chupacabra said:
I've been struggling with the focus issues on my G2 almost since I
bought it. I've gotten some good and but a lot of bad pictures. I
know this question has been beaten absolutley to death in this
forum, but I noticed something interesting today. I was
photographing protestors at a symposium my college was hosting, and
was very unhappy with some of the crowd shots I got. But I then
realized that every one of the pictures I had taken of
demonstrators with portrait mode had come out wonderfully sharp,
but many ones taken in AUTO mode or the mode just below auto (can't
remember the name- designed for quickly shooting scenes with a
large DOF without zoom) were unsharp and generally out of focus.
Out of 70 shots in portrait mode, not one was blurry. Out of 30 or
40 in auto, 1/3 are blurry. Is there any explaination for this?
What's the deal?

Shot in portrait mode and about half way between wide angle and
telefoto:



Shot in auto mode- I think there was enough there for the camera to
lock onto focus. Too much maybe?

Click to expand...
Click to expand...
Click to expand...
 
Chupacabra said:
That 193mm conversion was just what pbase spit out after reading
the exif info. I'm fairly proficient in photoshop, so sharpening
up most pictures is not a problem, but something like this is a
pain. But I guess my question is why did the auto mode on the
camera choose those settings if they would lead to a blurred image?
Click to expand...
IMO, program modes often make DUMB choices. A standard P&S camera will not have any apertures wider than f4 or f5.6, so this sort of problem doesn't happen. But it sure happens with a fast lens.

In good lighting conditions, I use Av with the aperture set to f4 or f5.6. I also keep an eye on the shutter speed. hope that helps, GKL
 
Chupacabra said:
There seems to be a lot of subtleties concerning the AF on the G2.
Has anybody made a post of collected tips on how to get it to shoot
properly? I often run into the problem of having to frame a shot a
certain way (like with landscapes)- if I meter on one place, focus
might be right, but white balance would be off or the other way
around.
Click to expand...
The G2 needs a vertical high contrast boundary to focus properly.

For more autofocus tips see:
http://www.dpreview.com/forums/read.asp?forum=1010&message=2890738
http://www.dpreview.com/forums/read.asp?forum=1010&message=2274360

http://www.dpreview.com/forums/read.asp?forum=1010&message=2987478
 
I understand your frustration, I really do. GKL's post just below your's has some focusing tips, give them a try and see if they help. Do you find that your G2 botches certain types of shots, have you found a pattern? Mine consistently screws up wide angle shots. If the subjects are further than 5-6 feet away, but closer than, say 15 feet, it infinity focuses and delivers a soft pic, no matter how much contrast I give it, very frustrating.

I thought the AF systems were the same on G1 and G2? But alas, I think some G2's focus better than others. If it's new, perhaps you can exchange and try a different one? When the shooting season is over, I am taking mine back to Best Buy to exchange using the extended warranty, a camera this expensive should be able to focus on people at wide angle. Good luck!

--
Eric
Disclaimer: Snapshooter, and proud of it ;-)
http://www.pbase.com/haglunde
Barbara House said:
Chupacabra said:
morris said:
The autofocus system uses contrast to focus. The camera found a
high contrast object in the foreground, the white rope agents the
green grass, and focused on it. Many prosumer digicams do this and
it is very frustrating. You have to learn to watch out for this
situation and lock the focus and then compose when this happens.
If the G2 had a better manual focus system I would suggest it, but
frankly manual focus is not what it should be.

Morris
Chupacabra said:
I've been struggling with the focus issues on my G2 almost since I
bought it. I've gotten some good and but a lot of bad pictures. I
know this question has been beaten absolutley to death in this
forum, but I noticed something interesting today. I was
photographing protestors at a symposium my college was hosting, and
was very unhappy with some of the crowd shots I got. But I then
realized that every one of the pictures I had taken of
demonstrators with portrait mode had come out wonderfully sharp,
but many ones taken in AUTO mode or the mode just below auto (can't
remember the name- designed for quickly shooting scenes with a
large DOF without zoom) were unsharp and generally out of focus.
Out of 70 shots in portrait mode, not one was blurry. Out of 30 or
40 in auto, 1/3 are blurry. Is there any explaination for this?
What's the deal?

Shot in portrait mode and about half way between wide angle and
telefoto:



Shot in auto mode- I think there was enough there for the camera to
lock onto focus. Too much maybe?

Click to expand...
Click to expand...
Click to expand...
Click to expand...
 
Barbara, I’m sorry to hear you so frustrated. A few months ago I ran into a woman at the Queens Botanical Gardens taking photos of her children with a G2. She asked a very simple question “How do I get those nice blurred backgrounds that I used to get with my SLR?” I showed her on my G1 and reminded her that everything works the same as a SLR. She tried it and away she went happily ignoring the fact that she was holding a digital camera in her hands and taking wonderful portraits and macro shots. Do you need to back up and think about the basics for a moment?

Morris
Barbara House said:
Chupacabra said:
morris said:
The autofocus system uses contrast to focus. The camera found a
high contrast object in the foreground, the white rope agents the
green grass, and focused on it. Many prosumer digicams do this and
it is very frustrating. You have to learn to watch out for this
situation and lock the focus and then compose when this happens.
If the G2 had a better manual focus system I would suggest it, but
frankly manual focus is not what it should be.

Morris
Chupacabra said:
I've been struggling with the focus issues on my G2 almost since I
bought it. I've gotten some good and but a lot of bad pictures. I
know this question has been beaten absolutley to death in this
forum, but I noticed something interesting today. I was
photographing protestors at a symposium my college was hosting, and
was very unhappy with some of the crowd shots I got. But I then
realized that every one of the pictures I had taken of
demonstrators with portrait mode had come out wonderfully sharp,
but many ones taken in AUTO mode or the mode just below auto (can't
remember the name- designed for quickly shooting scenes with a
large DOF without zoom) were unsharp and generally out of focus.
Out of 70 shots in portrait mode, not one was blurry. Out of 30 or
40 in auto, 1/3 are blurry. Is there any explaination for this?
What's the deal?

Shot in portrait mode and about half way between wide angle and
telefoto:



Shot in auto mode- I think there was enough there for the camera to
lock onto focus. Too much maybe?

Click to expand...
Click to expand...
Click to expand...
Click to expand...
 
I have a G1 and I never use Auto mode except when I bump the switch and don't notice the change. I notice pretty fast because the camera can't focus. I use P for all of my general purpose photos. Also, switch to single AF mode in P mode. You will then notice that the camera can actually focus. I don't understand why Canon even has the continous focus mode, I guess it is to give you the blur special effect. I think the Auto mode also takes bad pictures.

Ed
Chupacabra said:
I've been struggling with the focus issues on my G2 almost since I
bought it. I've gotten some good and but a lot of bad pictures. I
know this question has been beaten absolutley to death in this
forum, but I noticed something interesting today. I was
photographing protestors at a symposium my college was hosting, and
was very unhappy with some of the crowd shots I got. But I then
realized that every one of the pictures I had taken of
demonstrators with portrait mode had come out wonderfully sharp,
but many ones taken in AUTO mode or the mode just below auto (can't
remember the name- designed for quickly shooting scenes with a
large DOF without zoom) were unsharp and generally out of focus.
Out of 70 shots in portrait mode, not one was blurry. Out of 30 or
40 in auto, 1/3 are blurry. Is there any explaination for this?
What's the deal?

Shot in portrait mode and about half way between wide angle and
telefoto:



Shot in auto mode- I think there was enough there for the camera to
lock onto focus. Too much maybe?

Click to expand...
--
Ed
Canon EOS 3, Sony D700, Canon G1, Canon S330, Minolta D7i
http://www.cbrycelea.com/photos/ Old Pictures
 
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