burkphoto wrote:
A mechanical focal plane shutter uses curtains to time the exposure. An electronic “shutter” uses a video frame grab from the signal coming from the sensor. Each has advantages and drawbacks.
The image created by the mechanical shutter is always as good or superior to the shutterless sensor image, all else being equal.
Image quality used to be a high priority.
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I used visual comparisons of the same static test scene. Examining images at 100% view in Photoshop, I can see no difference between images at the same ISOs made with the same speeds
in different shutter modes.
Congratulations: you found the cases where the two designs are equivalent--or your monitor is not high enough resolution to see the problems.
I'd guess you took photos of an unmoving subject in good light with a "global shutter mode" (probably CCD) sensor. Yup: no difference.
Try make exposures (1) in low light; and (2) with a moving subject. If you still can't see the difference, print an 8 x 10. If it still
looks the same, I can recommend a good opthamologist. :-)
Shutterless and in low light, "global shutter" sensors will have blurred motion, while "rolling shutter" sensors may have a dark bar
on the image. If you don't believe me, ask B&H:
https://www.bhphotovideo.com/explora/video/tips-and-solutions/rolling-shutter-versus-global-shutterAlso,while a "global shutter" sensor will excel at your test, it may not look as good as a non-global shutter! It will have higher noise and
lower dyanmic range. It will also generate more heat (and drain your batteries faster). So one has to compare *six* types of sensors:
CCD "global shutter", CCD "rolling shutter" (uncommon), CCD neither, CMOS "global shutter" (uncommon), CMOS "rolling shutter",
CMOS neither.
Like you say all have "advantages and disadvantages". But if you want to equal film camera shutter performance, then you will
have a mechanical shutter (and a focal plane shutter will fall short of leaf shutter performance).
Dynamic range you absolutely cannot see on an LCD or OLCD screen. It's like looking for darkness with a flashlight.
The dynamic range of your image file could be much greater than your monitor can display--and you may need that
dyanmic range to decide which end to throw away for display or printing: highlights or shadows (or some of both).
In photography, what you see is never what you get--unless your final "print" is the preview LCD on your camera.
That will look different on the monitor and different still if printed on paper.
Looking out my window, I can see no evidence that the earth is spherical. But believe me, it is. "Seeing is believing"
only if one is an idiot.
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I do not have access to test equipment, other than the camera itself. To me, not seeing any visible difference is proof enough.
Don't you ever make prints? Saying that an image is sharp on a computer monitor ain't sayin' much.
The standard of "sharp" used to be a 12 x 18 print by Ansel Adams or Minor White. Now it's burkphoto's monitor.
How far we have fallen!
You could also take a photo of a white card, then use softtware to check the image file for noise.
(It used to be common for serious photographers to own test equipment.)
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This was an important test for me, since the silent electronic shutter is used in theatres to cover plays and concerts, and for macro work where I’m avoiding vibration
(mirrorless plus electronic shutter plus remote trip of the shutter via smartphone app = sharp images).
Indeed, very true. Focal plane shutter noise is a problem in quiet rooms. But the traditional solution
is a leaf shutter---and there are digital cameras with leaf shutters.
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Main disadvantage of mechanical shutter mode is noise and vibration, same as the reflex mirror. Main disadvantage of electronic shutter mode is the “rolling shutter effect” you see when video recording. It’s also visible in still photos when panning moving subjects.
These are the main disadvantages when shooting in *normal light* that can be seen in *low resolution*.
If you only shoot in normal light and view in low resolution, then read no futher.
But noise, loss of sensitivity and loss of resolution (compared to sensors not having shutter features) can
also be big problems. Remember, the sensor is kinda small in the first place (compared to traditional
photography). It's difficult to design and manufactuer a good sensor, and when the sensor also has to be
the shutter, it's even more difficult.
An analogy could be made with instant film: don't expect the highest image quality from a Polaroid.
Convenience and complexity always come at a price--and not just in monitary terms.