Live Bulb / Live Time - What is it?
With digital cameras, for dim scenes, you hold open the shutter and let the light stream through to the sensor. At some point in time, you decide that you have collected enough light so you close the shutter then, hit the Preview button so that you can expect the LCD for correct brightness of the image.
Live Bulb / Live Time enables you to peek at how the image is progressing so that you can decide when that the image is just right in terms of brightness so that you can close the shutter without wasting the current shot and trying again. If there are light trails or variable motion in the scene, Live Bulb / Live Time allows you to examine the scene as you are waiting for the long exposure shot to complete - you can then continue or abort if something is not what you want, early.
Any modern digital camera should be able to do this, but most designers haven't got round to it. Live Bulb / Live Time was first implemented by Olympus on the E-M5/OM-D, then subsequently the E-PL5, E-PM2 and further models.
What is the difference between Live Bulb / Live Time ?
Live Bulb means you open the shutter by squeezing the shutter release button and hold it down until you want to close it. It's best to use a remote shutter release rather than press the button on the camera body as you might introduce handshake motion.
Live Time means you squeeze down on the shutter release button and can remove your hand. When you want to close the shutter, you squeeze again.
Live Time means you squeeze down on the shutter release button and can remove your hand. When you want to close the shutter, you squeeze again.
How do you get to the menu(s)?
- Set the camera to M - for Manual Exposure (that's the M in the P A S M dial / menu)
- Set the Shutter Speed slower and slower - as I change the setting on my E-PM2, it goes 1" then 2" then it continues to 60" - it then goes to LIVEBULB and then to LIVETIME - I prefer to use LIVETIME because I don't normally have a remote control and don't want to stand there holding down the shutter release button.
Optional Settings
Noise Reduction
Setup . Gear . E (Exp/ISO) . Noise Reduction
I set this to OFF. This carries out Dark Frame Subtraction - if you expose for 20 seconds, the camera does that task and then shoots another exposure ignoring light for 20 seconds further - This Dark Frame represents the background noise of the sensor at that temperature. The camera then subtracts that noise from the real image and hopefully produces a cleaner JPEG. The issue is that if I shoot for 60 seconds, I can't use the camera for another 60 seconds. It does not affect your raw image file if you are shooting raw.
I set this to OFF. This carries out Dark Frame Subtraction - if you expose for 20 seconds, the camera does that task and then shoots another exposure ignoring light for 20 seconds further - This Dark Frame represents the background noise of the sensor at that temperature. The camera then subtracts that noise from the real image and hopefully produces a cleaner JPEG. The issue is that if I shoot for 60 seconds, I can't use the camera for another 60 seconds. It does not affect your raw image file if you are shooting raw.
Live Bulb / Live Time display refresh frequency
Setup . Gear . E (Exp/ISO) . Live BULB
or
Setup . Gear . E (Exp/ISO) . Live TIME
You can choose between 0.5 seconds to 60 seconds.
The refresh display time does not affect the exposure of your final image, it just means that if you choose too brief a refresh time, you will not be able see the last moments of your shot. If you choose too long a refresh time, you may miss that crucial moment when the brightness for the image is just right - and cause a bleached out image.
Let us work out a case for ISO 200, whatever you set, the display will only refresh for a maximum of 24 times. For half a second intervals, that means you can only see the screen refreshed for 12 seconds. For some fireworks, light painting or dimly lit cityscapes using ISO 200 f/16, you might need 30 seconds or even 60 seconds of light gathering. In that case you might consider 1, 2 or 4 second intervals. In a recent shoot, I found 2 seconds interval, worthwhile.
(One reason some of us are using f/16 is to accentuate the starburst of street lights and other point light sources.)
Normally, I prefer my LCD or EVF to simulate exposure darkness / brightness display - this is one of the differences between an Optical View Finder in a DSLR and electronic displays in mirrorless cameras. However, for long exposures, at night /f16, the electronic display becomes so dark that you cannot see clearly. Set the Live View Boost to On so that the camera does not attempt to simulate real conditions - the display remains bright all the time during Liveview for you to carry out focussing, aiming, framing activities.
When you start the actual exposure, then it LiveTime works normally.
When you are shooting in the dark, the Auto Focus system may not stay steady at one focus plane or may fail to settle on the object that you want. You might want to set Focus Mode to Manual Focus - MF.
When you are shooting on a long exposure, it is likely you will not be hand holding and be placing the camera on the tripod. Image Stabilisation instead of reducing handshake, may actually create sensor shake. Switch it off.
Want to see some videos demonstrating this feature? Click on YouTube Videos
or
Setup . Gear . E (Exp/ISO) . Live TIME
You can choose between 0.5 seconds to 60 seconds.
The refresh display time does not affect the exposure of your final image, it just means that if you choose too brief a refresh time, you will not be able see the last moments of your shot. If you choose too long a refresh time, you may miss that crucial moment when the brightness for the image is just right - and cause a bleached out image.
Let us work out a case for ISO 200, whatever you set, the display will only refresh for a maximum of 24 times. For half a second intervals, that means you can only see the screen refreshed for 12 seconds. For some fireworks, light painting or dimly lit cityscapes using ISO 200 f/16, you might need 30 seconds or even 60 seconds of light gathering. In that case you might consider 1, 2 or 4 second intervals. In a recent shoot, I found 2 seconds interval, worthwhile.
(One reason some of us are using f/16 is to accentuate the starburst of street lights and other point light sources.)
Live View Boost
Setup . Gear . D Display/Audio/PC . Live View Boost . OnNormally, I prefer my LCD or EVF to simulate exposure darkness / brightness display - this is one of the differences between an Optical View Finder in a DSLR and electronic displays in mirrorless cameras. However, for long exposures, at night /f16, the electronic display becomes so dark that you cannot see clearly. Set the Live View Boost to On so that the camera does not attempt to simulate real conditions - the display remains bright all the time during Liveview for you to carry out focussing, aiming, framing activities.
When you start the actual exposure, then it LiveTime works normally.
Manual Focus
Super Control Panel . MFWhen you are shooting in the dark, the Auto Focus system may not stay steady at one focus plane or may fail to settle on the object that you want. You might want to set Focus Mode to Manual Focus - MF.
Image Stabilisation
Super Control Panel . IS - OffWhen you are shooting on a long exposure, it is likely you will not be hand holding and be placing the camera on the tripod. Image Stabilisation instead of reducing handshake, may actually create sensor shake. Switch it off.
Want to see some videos demonstrating this feature? Click on YouTube Videos
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