The lunar craters Copernicus (left) and Eratosthenes were shot with Live View recorded as bitmaps at 1024 x 680 resolution by Images Plus Camera Control at approximately 6 frames per second. Taken with a Canon T2i (550D) and a C11 Edge working at f/10 at 2,794 mm of focal length at ISO 200 at 1/250 second exposure. Craters as small 1.8 km ( 0.95 arcseconds) are recorded. The low framing rate was caused by an old, slow laptop that was used.

Most DSLR cameras now have a Live View feature where we can view a live video image off the sensor in close to real time. It is displayed on the Liquid Crystal Display (LCD) screen on the back of the camera.

This LCD is also used to review images that have been shot, and for accessing, viewing and changing menu settings. Images displayed on Live View are very convenient when shooting. It gives us immediate feedback on whether an image is correctly framed, exposed and focused.

We can also enlarge the Live View video image and focus off the sensor itself in real time instead of trying to focus through the viewfinder, which can be extremely difficult to do with astronomical subjects.

DSLRs that have Live View usually have a way to output the Live View video stream to a monitor or computer. With software, we can record it on a computer.

Canon and Nikon DSLRs allow control of most of the functions of the camera as well as viewing Live View and even focusing camera lenses by remote control on a computer.

Although it was not really intended by the camera manufacturers, we can use special software to record the Live View video signal.

This trick is not of much use to normal daytime photographers because most recent DSLR cameras will also record high-definition video in the camera, but it is very useful for planetary photography because it allows access to 1:1 pixel resolution. And we can even use this method to record Live View video to a computer on a camera that doesn't even record high-definition or standard definition video in the camera, as long as it has Live View with an output connection.

Depending on the speed of the computer system, we should be able to record about 10 to 28 frames per second, more than enough to do lucky imaging.

Live View can only be recorded to a separate computer and cannot be recorded in the camera.

Live View and 1:1 Pixel Data

For DSLR astrophotographers the capability of recording Live View is actually quite useful. It allows us to access that 1:1 pixel data that we need for high-resolution video lucky imaging.

Although the full frame video in Live View is not 1:1 resolution, we can access 1:1 resolution by using a simple 5x zoom feature.

Note that some cameras and software give you the ability to zoom in to more than 1:1 resolution. For example, the Canon T3i (600D) allows a "digital zoom" up to 10x. This is really of no use to us because it does not produce any more true resolution or detail, so it should be avoided for high-resolution planetary imaging.

When we are at 1:1 resolution, we are using only a very tiny portion of the central part of the sensor. This makes the field of view very small. But this is really ok for planetary work because most of the planets are very small to start with.

For example, with a Canon T2i (550D), the full resolution is 5184 x 3456 pixels in a sensor that has a physical size of 22.3 mm x 14.9 mm. When we use Live View with 5x crop mode, we get an image that is only 1024 x 680 pixels from the center of the sensor. This corresponds to a physical size on the sensor of just 4.4 mm x 2.9 mm.

Inside of this 4.4 mm x 2.9 mm rectangle, each pixel is 4.3 microns on a side. Accessing these pixels at 1:1 resolution is what makes high-resolution planetary lucky imaging possible.

Here are some examples of the 1:1 pixel data that can be recorded with Live View at 5x magnification with Canon DSLRs:

Software for Recording Live View

Canon DSLR cameras come with free software called EOS Utility that allows control of the camera and viewing of remote Live View. It will also allow you to start and stop the recording of high-definition video, but only on the memory card inside the camera itself. You can not use this software to record Live View.

Nikon offers software called Camera Control Pro 2 that will control the camera and allow remote Live View, although, again, you cannot record the Live View video with this software.

Software that can be used to record Live View from Canon DSLR cameras for planetary imaging:

Canon

• Astro Photography Tool - Commercial software - Advanced software that offers camera control as well as focusing metrics, control of an electronic ASCOM focuser, basic control of your telescope mount, and many other features. Astro Photography Tool records a series of high-quality compressed JPEGs out of the camera's Live View video stream which can be opened directly in RegiStax, AviStack or AutoStakkert!2.

• Backyard EOS - Commercial software - Advanced software that offers camera control as well as focusing metrics, and control of an electronic ASCOM focuser, and many other features. Backyard EOS records an AVI file that can be opened directly in RegiStax, AviStack or AutoStakkert!2.

• EOS Camera Movie Record - Freeware - EOS Camera Movie Record offers basic camera control and recording. Records to an AVI file that you can open in RegiStax, AviStack or AutoStakkert!2.

• Images Plus - Commercial software - Advanced software that offers camera control as well as focusing metrics, electronic focuser control and many other features. The big advantage to Images Plus is that it records the uncompressed Live View video to an uncompressed SID file format. The SID file is comprised of each individual bitmap video frame from the camera. The individual frames can be exported out of Images Plus as individual BMP bitmap format images that can be opened in RegiStax, AviStack or AutoStakkert!2. Each frame is about 2 megabytes, so the SID file, since it is uncompressed, can get very large very quickly.

Software that can be used to record Live View from Nikon D90, D5000, D5100, and D7000 camera models for planetary imaging:

Nikon

• Images Plus - Commercial software - Advanced software that offers camera control as well as focusing metrics, electronic focuser control and many other features. Records Live View video to an uncompressed SID file format. The SID file is comprised of each individual bitmap video frame from the camera. The individual frames can be exported out of Images Plus as individual BMP bitmap format images that can be opened in RegiStax, AviStack or AutoStakkert!2. Each frame is about 2 megabytes, so the SID file, since it is uncompressed, can get very large very quickly.