StellaCam3 (a modified Watec 120N+)

The StellaCam3 by Astrovid is a modified Watec 120N+ which uses the Sony ICX249AL sensor reading out 752 x 582 pixels in CCIR mode. With a separate control box, the camera can be commanded to integrate up to 256 frames and use shutter times down to 1/2000 s. The StellaCam3 has a built-in Peltier cooler. I simply recorded the video data generated by the camera via a PAL-to-USB converter (Conrad Electronics) and used VirtualDub to grab AVI files. For some reason I could not visualize individual even or odd fields with VirtualDub, so I used LiMovie which I happened to have on the PC for visualisation. For a screenshot, look here.

The camera was used with a 50 mm Nikon lens f/1.4. The shutter time was set to 1/2000 s. The analog signal was routed through the control box of Rolf's time machine and the inserted time was compared to the LEDs. Several AVI sequences were grabbed and the following table gives the data for 8 fields as an example.
 
Frame number (Run5.avi, 16 Aug 2008) time inserter Running light clock Difference in ms
210 odd 14:15:54.387 0.347 40
210 even 14:15:54.407 0.367 40
211 odd 14:15:54.427 0.387 40
211 even 14:15:54.447 0.407 40
212 odd 14:15:54.467 0.428 41
212 even 14:15:54.487 0.448 41
213 odd 14:15:54.507 0.468 41
213 even 14:15:54.527 0.488 41
Average 40.5 +/- 0.5

As measured before by G. Dangl, this Watec also shows a delay of 40 ms, i.e. the signal by the time inserter is inserted 40 ms after the actual image acquisition.
 
 


Created by dvk,  26 Aug 2008, updated 29 Aug 2008.
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