What causes blurred/non-sharp images taken of stable objects?

Question

I know about two important reasons which are motioning or shaking camera/hands and dust and dirt on you lens but if you have fixed them and still you have blurred/non-sharp results, what can be the reason?

I am talking about DSLR Canon cameras and lenses.

Answer 1

uhhhh :p may be earth quake?? :p (really may be)

You see id like to know how old your camera is, and did you drop it or crash it at some point of time?

why i am asking is because, if you are cent percent sure that your tripod is stable then, the sensor may have become a bit shaky if in any of the above case...so no matter what shutter speed and stability you set, the photo might get blurred if the sensor inside your camera shakes....(even if the shake is like micro meter :p if the sensor is loosely held by the camera ) it may even shake due to tiny vibrations like mirror flip.

this is the only reason i could come up with as per your description. so i would prefer you taking your beloved camera to an authorized service center and giving it a full body check up :p :)

happy clicking :)

Answer 2

The three primary contributors of blur and/or softness in most pictures are:

• Camera motion
• Subject motion
• Incorrect focus

Additional contributing factors can be:

• Narrow Depth of Field
• Diffraction
• Use of tilt/shift with a capable lens
• Chromatic Aberration
• Lens Distortion
• Misaligned/Decentered lens elements
• Misaligned lens mounting flange
• Poor lens design/quality of construction
• Damaged/Dirty lens elements or sensor

Fingerprints or dust and dirt on the lens need to be pretty bad before image quality is significantly affected.

Answer 3

Blur and softness can easily be confused. If the camera is truly stable and subjects stationary, there can still be softness which looks like blur. With most - more so on low-quality ones - lenses, you will get softness at maximum aperture and with all lenses you will get softness past the diffraction limit which cause blur at small apertures.

If you are seeing blur which cannot be attributed to lens softness, then something must be shaking. Even on a tripod, vibrations are possible. Cheaper tripods may not be stable and even pushing on the shutter can vibrate the camera and lens.

Another cause of blur is shake from the mirror or shutter. Not much can be done about the latter but the former can be avoided using mirror-lock on most cameras. Some cameras automatically engage mirror-lockup when the short self-timer starts.

Answer 4

You seem to use a canon 5d mark ii

If the image is of something at the same distance (ex: a wall?)

• See if the micro-focus adjustement setting is on (and try turning it off)
• or if it was off, try to turn it on and see if you can find an adjustment that correct the effect.

If the image is of things at several distance from the sensor

• If there is blur at different depth, it's probably due to a shake of the camera (or the tripod, or both) when you press the button. It is usually due to the pressure/release itself, and also to the opening of the mirror before the shutter opens. To reduce that:
  • use a remote control instead of using the buttons on the camera
  • and also set the camera to use 2-steps shooting (the first step opens the mirror, the 2nd opens the shutter to take the photo). The first step usually shakes much more the camera than the 2nd. So by using the 2-step feature, the first one will be done in advance and then the camera returns to stability, and the 2nd one takes the picture. But don't wait too long between the 2 as dust (from area between the back of your lens and the camera) could enter the sensor more easily while the mirror is up