C&C Sharp enough or missed focus

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Feb 28, 2019
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Olympus EM1-X and 300mm F4 ...so good kit. I think the lens is just not good enough.

1/500 sec at F4.0 ISO 160 - balanced on a post.
Using LR Plugin, focus point is right on the neck.
DOF is 0.38m
Distance is 16.99m

So body facing us is far sharper than the head and that can only be about 1cm in depth.

OK it could be my technique, or is cropping in to get he bird to fill the frame, too much to expect from this kit. Filling the frame is on a 27in monitor?
 

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I'm not sure what you are asking.

If you are talking about cropping to have the bird fill the frame, that would be a ~50% crop. So then your 20MP image becomes a 10MP image - viewed on a 27in monitor. That isn't a deficit of the lens, it's a deficit of resolution.

Solution - get closer.
 
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The bird takes up about 1/9th of the frame. So if you crop to "fill the frame", you end up with 20/9 = 2.2 megapixels. Nowhere near enough for your 27" monitor (even if it's just QHD rather than 4K).

So like the others said: get closer and focus on the eye. This is almost certainly user error, and not a problem of the gear you are using. (Although it's quite hard to judge sharpness from a resized image. Remember that images on this forum are resized to 1600 pixels on the long end.)
 
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Not really sure what you are getting at, but if you are wanting a photograph of a bird filling the frame than get close enough to fill the frame with your subject. Or at least to fill 1/2 the frame. There is no system that you can crop 9/10 of the image and expect good results.
 
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sorry if my point is not clear.
1 - at that distance, if the wing is in focus, why is the eye not as the DOF should cover that range. They should both be similar sharp or soft.

2 - should I really be expecting a sharp image if I crop to only have the bird? In other words, at what resolution/crop should you determine sharpness?
 

RichardC

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sorry if my point is not clear.
1 - at that distance, if the wing is in focus, why is the eye not as the DOF should cover that range. They should both be similar sharp or soft.

2 - should I really be expecting a sharp image if I crop to only have the bird? In other words, at what resolution/crop should you determine sharpness?

It depends where the lens is focused.

Is the wing in focus because the lens is focused short of the bird with depth of field helping you out?

Why not pop the camera on a tripod and do some tests (IBIS off) on a bird sized target? If you get pleasing results then you are free to concentrate on your technique. If however your images are soft, focus manually. If the sharpness improves with manual focus, consider fine tuning the autofocus.
 

fredlong

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sorry if my point is not clear.
1 - at that distance, if the wing is in focus, why is the eye not as the DOF should cover that range. They should both be similar sharp or soft.

2 - should I really be expecting a sharp image if I crop to only have the bird? In other words, at what resolution/crop should you determine sharpness?
1. This is an educated guess. The camera focuses “somewhere” within the depth of field. Not necessarily where it would best for the image being captured. It doesn’t know what you want.

A second consideration is subject movement. The old rule of thumb for a “reasonably” sharp image is a shutter speed equal to 1/focal length, FOR AN 8X10 PRINT VIEWED AT ABOUT 12”. If a viewing size isn’t specified the shutter speed is meaningless. Translated to m4/3 that’s a shutter speed of 1/600 of a second. You’re borderline for stopping subject motion. Stabilization has no effect on subject motion. Birds are twitchy.

2. You should NOT expect a sharp image if it’s cropped down to just the bird and enlarged to a 27” screen. Maybe with a 100 megapixel medium format image. Maybe.
 

fredlong

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There’s one more thing I’ll add about depth of field. There’s only a single plane of sharpness in a focused image. There’s a range before and after the plane of sharpness that is “close enough" to look in focus. There’s a general rule for this, but final reproduction size and viewing distance make any “rule” approximate.
 

PakkyT

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Sorry everyone, a nitpicking reply to several...

cropping to have the bird fill the frame, that would be a ~50% crop. So then your 20MP image becomes a 10MP image

I think you mean 5MP if you are talking about cropping both height and width 50% which leaves you with one-quarter of the image.

1 - at that distance, if the wing is in focus, why is the eye not as the DOF should cover that range. They should both be similar sharp or soft.

The image is so small that perhaps your monitor and eyes are better than mine, but I find it very difficult to call any different parts of the bird sharper or blurrier than any other parts of the bird.
If you are concerned with your lens you need a much closer subject to judge that or as @RichardC suggested, setting up a controlled target test to see how the lens behaves taking out the user to user variance.

The old rule of thumb for a “reasonably” sharp image is a shutter speed equal to 1/focal length [snip] Translated to m4/3 that’s a shutter speed of 1/600 of a second. You’re borderline for stopping subject motion.

The 1/fl rule of thumb is to stop camera shake, not subject motion.
 

Clint

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1. Your DOF may not have been what you thought or (a) your shutter speed may not have been fast enough (b) heat distortion
2. You should not expect a subject that fills 5% of the image area to produce the results you expected. So get closer and focus where you want - so you need to be close enough to focus on the exact spot you want in focus. Even then (a) or (b) above can easily cause something to appear out of focus.
 
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OK folks ... a little lunch time shot in the garden. Tried to get closer and make sure of the focus point.
P3290005 v2.jpg
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F5.6 1/640 second (balanced on a gate post) and ISO 2500

Focus on the eye ... or as best as I could.

Is this sharp?
 
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Jun 8, 2019
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Is this sharp?
Seems very sharp to me, but like I said before, it can be hard to judge from a resized picture.

It seems you focused on either the nose or the whiskers, and not on the eye. Conventional wisdom says that you should focus on the eye. But the nose and whiskers look very sharp. :)

(Also notice that you might lose some detail because of noise reduction at ISO 2500. Maybe you didn't have any other choice than to raise the ISO, but it's something to keep in mind while doing this pixel-peeping exercise.)
 
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