Orion 52186, 52185 instruction manual Typical Camera Settings, Astronomical Imaging

Figure 16. Globular cluster M13 using 256x sense up, AGC on and ALC shutter off.

Typical Camera Settings

Terrestrial, Lunar, Planetary and Solar.

WHITE BAL.	-	ATW
ALC/AES	-	ALC (SHUTTER
1/10000 to 1/100)
AGC	-	OFF
SENSE UP	-	OFF

Figure 14. The moon’s surface detail looks the best along the terminator.

at the terminator (that tiny thin line between the shadow and light, see Figure 14). To get more of the moon in the image, a focal reducer will need to be used. For close-ups of craters use a Barlow lens (see “Using Focal Reducers and Barlow Lenses”).

Planetary Imaging

The best planetary images will be obtained by stacking (combining) many individual images in order to reduce noise, atmospheric effects

Figure 15. Planetary imaging stacking.

Low Light Deep Space Objects.

WHITE BAL.	-	AWB/ATW
ALC/AES	-	ALC (SHUTTER OFF)
AGC	-	ON
SENSE UP	- ON (x2 to x256)

Try several different settings to get a feel of how the camera controls work and affect the resultant image on the computer screen. The SHUTTER speed (ALC) and SENSE UP controls are the ones you will use the most.

The telescope being used, seeing conditions, and object being imaged will dic- tate how these camera controls should be set.

Astronomical Imaging

Now that you’re familiar with basic camera and software operation, it’s time to take the DSVC out at night under the stars to capture some astronomical imag- es. We recommend starting with the Moon, as it is easy to acquire into the cam- era’s field of view, and typically does not require stacking of multiple exposures as planetary images do.

Lunar Imaging

Imaging the Moon is much like imaging terrestrial objects during the day. Since the exposure is very short, it is not critical that the telescope be precisely polar aligned.

When the moon is past first quarter, it is hard to get detail due to the tremen- dous glare off of the lunar surface. Most detail, even on a thin crescent, will be

and improve image contrast, bright- ness, and detail (Figure 15). This is accomplished using one of the many post processing software tools such as Registax or AVIStack. (see

SOFTWARE)

A great way to obtain images for stacking is to take several seconds of video of the planet, then break the video into individual frames for stack- ing. Since the DSVC has a maximum

frame rate of 30 frames per second for NTSC (25 frames per second for PAL), you can literally obtain hundreds of images for stacking in seconds! You save time by taking one video instead of dozens of individual pictures!

Since you will be taking multiple images over a period of time, it is important you have a decent polar alignment in order to keep the planet within the field of view of the camera. To this end, having a motor drive (at least single-axis) will also be helpful. Otherwise, you will periodically need to rotate the R.A. slow-motion knob to keep the planet within the camera’s field.

Deep Space Imaging

Deep space imaging requires the longest exposure times and therefore having a good polar alignment and accurate tracking is critical to keep the target on screen.

Multiple Deep space images can also be stacked and/or tuned via software in order to reduce noise, atmospheric effects and improve image contrast, bright- ness, and detail.

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