ZeroCam: High Speed Intensified Astronomical Imaging

 

Deep Space Lucky Imaging

Image intensification permits very short sub-exposures of deep space objects, opening up new ways to create high resolution images with high dynamic range.  Atmospheric seeing continually shifts and shapes images.  Very short exposures of intensified imaging allow for fine reconstruction and editing of the ever changing image.  This technique is well known and commonly used for lunar and planetary imaging, where the object is sufficiently bright to be detected by a digital camera in a short exposure.

 

Photon Counting

With sufficient spatial and temporal resolution, an intensified camera is capable of detecting individual photons.  The camera operates in the photon counting regime when the photon density per frame is low enough to discriminate individual photons. This is achieved by high frame rates (10-30 FPS) and slow f-ratio (f/24-40).  Special processing is applied to photon counting data streams. Each photon in each frame is reduced to a single 1 bit data point then the data points are combined to create the image. 

 

ZeroCam Technical Information

 

Example Images from ZeroCam

 

M42 Trapezium area

10” f/16 Classical Cassegrain

ZeroCam  835 sec / 100ms/frame; H-a Filter (10nm)

Photon Counting with frame selection (2377 of 8354)

m42_ZeroCam3.jpg

 

Core of M13 with 0.5 arcsec resolution

20” Newtonian (Benoit Schillings) at f/20

ZeroCam 213 sec / 30ms/frame

Photon Counting with frame selection (2095 of 7087)

m13_sqr_30ms_g17 PC9-BS1 sel 2095 of 7087.JPG

 

M63 Galaxy

14.5” RCOS

ZeroCam Photon Counting 33ms x 78,000 (43 minutes)

m63_78Kx33ms_PC.jpg

 

M3

ZeroCam Phton Counting 14.5” RCOS

M3_63ms_g13_PC1.jpg

M17  Nebula

14.5” RCOS at f/24

Stack of 76,000 frames (20 fps * 1 hour)

M17_20FPSx76039.jpg

 

 

M57 Ring  Nebula

14.5” RCOS at f/24

Stack 180,000 frames (31 fps * 1.66 hour)

M57_31FPSx180k.jpg