why is it?

just jon

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Jonathon
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when my DSLR camra is about 5" to7"feet away from a small object
a light flashes to say its in focus .and i take the shot . but when i enlarge it a little on on the camra's lcd screen its out of focus same goes for when i upload it to the computer an put it on screen
 
May be the focus is somewhere else other than the object you are taking a photo of. Other issues may be shutter speed and camera shake.
 
Possibly shallow dof too

1) I did it on AF
2) also i tried on P setting then Manual all had the same results .
and tried diferent lens , Also tried different DOF
 
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Is the camera's active focus point over the object?
Is the object so small that something else is stealing focus? Is any part of the image in-focus?
Is you shutter speed fast enough?

Check your shutter speed. Try standing closer or using manual focus.

(Edit: Can you show us the picture, with EXIF data?)
 
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...a light flashes to say its in focus...
I don't know about Sony cameras, but a flashing focus light on my Canon means focus has not been achieved.
I might be giving you a red herring here, if Sony cameras do actually flash their light to indicate focus achieved. :shrug:

Mike.
 
Is the camera's active focus point over the object?
Is the object so small that something else is stealing focus? Is any part of the image in-focus?
Is you shutter speed fast enough?

Check your shutter speed. Try standing closer or using manual focus.

(Edit: Can you show us the picture, with EXIF data?)

Brightness Value: 1.12
Color Space: sRGB
Compressed Bits Per Pixel: 8
Contrast: Hard
Custom Rendered: Normal process
Date Time Digitized: 2013:07:26 10:43:27
Date Time Original: 2013:07:26 10:43:27
Exif Version: 2.2.1
Exposure Bias Value: 0
Exposure Mode: Manual exposure
Exposure Program: Manual
Exposure Time: 1 / 25
Flash: Flash did not fire, compulsory flash mode
FlashPix Version: 1.0
FNumber: 3.5
Focal Length: 35
Focal Length In 35mm Film: 74
ISO Speed Ratings: 400
Light Source: unknown
Max Aperture Value: 3.61
Metering Mode: Pattern
Pixel X Dimension: 3264
Pixel Y Dimension: 2176
Saturation: High saturation
Scene Capture Type: Standard
Sharpness: Soft
White Balance: Auto white balance
ImageStabilization: 3
Lens ID: 25511
Lens Model: Minolta AF 35-70mm F4
 
Exposure time 1/25 could be the problem. Any chance you could post the image up?
 
At 1/25 I should think there is a high probability of camera shake!
 
Just in case Jonathan doesn't know the rule of thumb regarding minimum shutter speed to prevent camera shake on a APS-C camera with 1.6 crop factor, it's:

1 / [focal length * 1.6]

So, at 35mm you'd want a minimum shutter speed of 1/60 (it's actually 1/56 but it's always better to round up).

Of course this is only a guide - it's possible, with good technique, to shoot clean images at slower speeds, and conversely, with poor technique to produce blurred images at higher speeds, but it's a good starting point.

Without seeing the picture it's impossible to say with certainty that camera shake is the problem, but it's looking like the most probable reason at the moment.
 
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Er, isn't there a difference between "out of focus" which comes from not focusing correctly or focusing correctly but accidently moved camera forwards or backwards and forgotten to refocus, as well as not using depth of field correctly, against that of "blurred images" which comes from camera shakes, slower shuttle speed, too much compression, trying to zoom in too much.

To the OP: Jon, I think in my option you did focus correctly (because your camera told you), but when you try to enlarge the image, the more you zoom in, the more blur it looks, it is not a case of focusing, it is a case of pixels. No matter how high the MP the camera have, the more you zoom in, the more you enlarge, the more likely you'll start seeing a blurred image. It's like buy a newspaper, use a microscope to look at the photos, and you'll notice that instead of seeing a clear face, you're looking at dots of dried ink. I would stay you have enlarged too far, so it would seems that's as far as you can get, specially as your EXIF data did mention "Sharpness: Soft" and that the object you took photo of is very small.

Also, I can't tell from the EXIF data, I'm not sure what level of picture quality setting you have it on, most cameras will say something like FINE, NORMAL, BASIC, or similar, if you set to lower quality in order to squeeze more number of images to memory card, you are compressing the images too much, some details will have been lost, hence the more you zoom in, the sooner the blurred look start to show, but setting to higher quality, althought lower the number of photos you can save to memory card, would result in less compression, saving every pixels it can, so the more you zoom in, the later it will show blurred look.

Also, even if it is really a case of out of focus than blurred image, it is likely that you have took the photo far too close with the wrong sort of lens, micro lens would be better suited to this kind of close up, the closer you take photos with any lens, the more depth of field you lose so it becomes more tricky to try to get pin-sharp focus on a very small object at very close range unless you use micro lens, most cameras and lens will have a minimum focusing range, same as your eyes do, you can't focus very well when you hold an object right againt your eyes.

It could also be camera shake, but I don't think trying to use a minimum shutter speed and not going any lower will help, what really would help the best is to use a tripod. What if this small object the OP spoke of happens to be a flower outdoor? The flower's movement in the wind, hand-holding a camera, minimum speed, all add up to more higher chances of blurred image, so a tripod to hold the camera steady and a faster shutter speed will help to freeze the image.

Well, it would help if we could look at your photo so we would know how to offer better advice.
 
i think the Exposure Time of 1 / 25 will show up any movement of your hands and cause blur/camera shake, also your Sharpness is at the soft setting now i dont know your camera but could this be a soft focus setting as you can buy a soft focus lens, it looks like your shooting in raw you dont lose any detail even if your camera was set to fine normal etc , can you post the photo up using flicker
 
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Major Eazy, I think you're obviously put a lot of effort into what was supposed to be a very helpful reply, but you've either expressed it poorly or just misunderstood yourself. If correct focus has been achieved, the picture should be sharp, at the very least, at the point of focus. I know I can easily take a 200% crop from one of my pictures and expect it to view reasonably wel on a screen - I just wouldn't expect to take a large print from it.

With regard to the macro lens thing, read what the OP has said - he is focusing 5 to 7 feet away, that hardly necessitates a macro lens. Besides, if the indication he is getting from the camera is a focus confirmation, again it says that he is not troubling the minimum focus distance - if he was too close it wouldn't beep/flash to suggest it has been achieved.

As said, 1/25 is a very slow shutter speed to be handholding. A tripod is only of use if the thing being photographed isn't moving - a tripod itself doesn't allow a higher shutter speed, which is how your post suggests it would help. Increasing aperture, or ISO would give a higher shutter speed that might freeze the action and not be affected by camera shake.
 
With regard to the macro lens thing, read what the OP has said - he is focusing 5 to 7 feet away, that hardly necessitates a macro lens. Besides, if the indication he is getting from the camera is a focus confirmation, again it says that he is not troubling the minimum focus distance - if he was too close it wouldn't beep/flash to suggest it has been achieved.

He also mentions 5" to 7" which implies 5 to 7 inches, then being that close, a macro lens would be more useful wouldn't it?
 
He mentions 5" to 7" feet, which is a bit ambiguous. No matter if it's feet or inches, at 1/25 my money is on camera shake.
Lob the camera on a tripod, wall or something else to rule out camera shake and you'll know for sure.
 
Apart from the hand shaking slow shutter speed, it could also depend on what AF area is being used.

On Sony DSLR you have a choice of:
wide
3 point zone
spot
Local

I would suggest the OP did not use SPOT focus- this would be the most appropriate for single / small objects

Just a though

Les :thumbs:
 
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