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DPChallenge Forums >> Hardware and Software >> sharpness and focus
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07/29/2010 02:54:16 AM · #1
I have noticed some of my photos are not very sharp or in focus. I have an Olympus 450 with the stock lense. I normally use auto focus. Do most of you use manual focus? besides adjusting the sharpness meter on my camera what else can I do to make it more sharp? is the auto focus in the camera or the lense? Thanks for the help
07/29/2010 03:03:33 AM · #2
sorry this was supposed to go in tips and tech. Can someone please move it to that form
07/29/2010 03:26:36 AM · #3
Each lens is sharper in a small aperture range around 8-16. This range change for all lenses so try all apertures on your lens to find the best ones.
It also work for focal lenght...
And your lens look sharp Olympus 14-42mm!
07/29/2010 05:19:54 AM · #4
The autofocus is in the camera - but it is unlikely that it is at fault unless you are really unlucky and it is simply broken.

What sort of settings are you using on the photos where you have a problem? Not knowing this is could be:

* Camera shake due to a longer exposure than should really be handheld.
* Autofocus having difficulty in low light
* High ISO making the photo look a little less sharp
* Shutter speed too low to freeze subject movement - sometimes this has to be remarkably high for birds / planes etc!

If you simply need to establish that your camera / lens combination works, try using a tripod, remote release (or timer), mirror lock up (if available) and a stationary subject. Try manual focusing, then the same using autofocus and see how they compare.

You may also want to check out this thread for ideas.

07/29/2010 12:55:05 PM · #5
I seem to be having more problems with close up still shots. when I am really close to my subject. I my ISO has been 100-200 and shutter at 1/20th of a second hand held, with good light. how does apeture effect at different distances because i normally am using a lower apeture setting? At 1/20th should I be Tripoding?

Message edited by author 2010-07-29 12:55:49.
07/29/2010 01:02:44 PM · #6
Originally posted by E450:

I seem to be having more problems with close up still shots. when I am really close to my subject. I my ISO has been 100-200 and shutter at 1/20th of a second hand held, with good light. how does apeture effect at different distances because i normally am using a lower apeture setting? At 1/20th should I be Tripoding?


Yes, you should be using a tripod at 1/20th. If you were closer to 1/125th you could get away without using a tripod, but 1/20th is not enough to avoid camera motion.

On top of that, your post processing should involve some sharpening as well. I learned the Adamus technique from DPC a while ago, and it works amazing for photos that are resized for web. Check post #3 in this thread
07/29/2010 02:08:09 PM · #7
Also, when doing closeups, make sure that you're within the focusing range of the lens. All lenses have a minimum focusing distance. This distance varies by focal length. The more you zoom in, the further away you need to be to achieve focus.

One way to avoid this when using auto focus is to set the camera to not allow the shutter to be pressed all the way if focus cannot be achieved.
07/30/2010 04:55:17 AM · #8
From your last post, the minimum focus distance question jumped out at me too.

I respectfully disagree with the post that you must use a tripod at 1/20th exposure time. For a start your lens is 14-42mm (correct?). The reciprocity rule dictates that the fastest handheld shutter speed you can use is the inverse of your focal length. So with this lens at 14mm, you could hand hold at 1/14 (and at 42mm, 1/42 or realistically 1/50).

That is only a guideline though. Image Stabilisation helps, good position helps and frankly so do steady hands. Lack of choice can also be a factor as with this shot in St Peters Basilica, where tripods are not allowed! Hand held at 1/15th, although I also got some shots in there down at 1/4s hand held which I was pretty happy with.



Like flash, tripods are great but it is useful to practice working without them sometimes.

Message edited by author 2010-07-30 04:55:54.
07/30/2010 08:04:56 AM · #9
Originally posted by FrankRobinson:

From your last post, the minimum focus distance question jumped out at me too.

I respectfully disagree with the post that you must use a tripod at 1/20th exposure time. For a start your lens is 14-42mm (correct?). The reciprocity rule dictates that the fastest handheld shutter speed you can use is the inverse of your focal length. So with this lens at 14mm, you could hand hold at 1/14 (and at 42mm, 1/42 or realistically 1/50).

That is only a guideline though. Image Stabilisation helps, good position helps and frankly so do steady hands. Lack of choice can also be a factor as with this shot in St Peters Basilica, where tripods are not allowed! Hand held at 1/15th, although I also got some shots in there down at 1/4s hand held which I was pretty happy with.



Like flash, tripods are great but it is useful to practice working without them sometimes.


That guideline that you are talking about uses the 35MM effective focal length. So his 14-42 lens is actually a 28-84MM lens. Meaning 1/30 should be the slowest and realistically since at closer focusing distance things are more exaggerated than you should go faster with the shutter to avoid motion blur.
07/30/2010 09:36:55 AM · #10
We're in the digital age. If you're at a slower-than-optimal (based on the reciprocity rule) shutter speed, fire off a few shots in continuous mode and THEN check the results.
07/30/2010 01:47:25 PM · #11
Originally posted by FrankRobinson:

I respectfully disagree with the post that you must use a tripod at 1/20th exposure time ... Image Stabilisation helps, good position helps and frankly so do steady hands.

Don't forget getting lucky, too! This recent entry was taken hand-held from about 25-30 feet away, 35mm equivalent focal length was 142.8mm. ISO 400, f/3.51, 1/15 second exposure. The display is closer and animated, yielding some motion and DOF blur, but Isaac looks in-focus enough to me. Next time I'll try to remember to use burst mode. :-)

07/30/2010 05:16:32 PM · #12
Originally posted by MattO:

Originally posted by FrankRobinson:

From your last post, the minimum focus distance question jumped out at me too.

I respectfully disagree with the post that you must use a tripod at 1/20th exposure time. For a start your lens is 14-42mm (correct?). The reciprocity rule dictates that the fastest handheld shutter speed you can use is the inverse of your focal length. So with this lens at 14mm, you could hand hold at 1/14 (and at 42mm, 1/42 or realistically 1/50).

That is only a guideline though. Image Stabilisation helps, good position helps and frankly so do steady hands. Lack of choice can also be a factor as with this shot in St Peters Basilica, where tripods are not allowed! Hand held at 1/15th, although I also got some shots in there down at 1/4s hand held which I was pretty happy with.



Like flash, tripods are great but it is useful to practice working without them sometimes.


That guideline that you are talking about uses the 35MM effective focal length. So his 14-42 lens is actually a 28-84MM lens. Meaning 1/30 should be the slowest and realistically since at closer focusing distance things are more exaggerated than you should go faster with the shutter to avoid motion blur.


Interesting - I saw a similar discussion not so long ago, which took a different point of view. Since the relationship between camera shake and focal length is related to magnification (and the magnifying effect of the lens on each tiny movement), we decided that the crop factor was not relevant in the law of reciprocity, since it only really affects field of view, not magnification.

A 50mm lens is a 50mm lens, producing a fixed magnification regardless of how much of that the sensor captures.

Would you disagree? I would be interested to hear a different point of view.
07/30/2010 05:18:10 PM · #13
Originally posted by GeneralE:

Originally posted by FrankRobinson:

I respectfully disagree with the post that you must use a tripod at 1/20th exposure time ... Image Stabilisation helps, good position helps and frankly so do steady hands.

Don't forget getting lucky, too! This recent entry was taken hand-held from about 25-30 feet away, 35mm equivalent focal length was 142.8mm. ISO 400, f/3.51, 1/15 second exposure. The display is closer and animated, yielding some motion and DOF blur, but Isaac looks in-focus enough to me. Next time I'll try to remember to use burst mode. :-)



Luck plays a key part in a lot of my photography - I'm not kidding myself about that! ;o)
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