pinhole 'lens' to test Lodestar

[nytecam]

In the absence of a 'C' lens on the Lodestar to do some daylight testing that's all's well with a the camera - a simple pinhole in ali [baking] foil may help.  Pic below shows the setup.  Due to the exceptional 'speed' of the the new Lodestars the "lens aperture" [via the pinhole] must be very small - typically <0.5mm but pinholes in foil are very cheap so experiment !

The foil is taped directly over the Lodestar front end and a pin or needle gently pierced centrally.  Measuring my pics against the known diameter of the Lodestar [say 33mm] - the pinhole = 0.17mm or f/50 against a 'focal length' of ~8mm eg foil to sensor distance.  

Typical exposures under daylight in the study ~0.5s - 2s.  The images of the room are very blurred but the shade of grey [not 50!] are proof the camera is ok prior to working at the telescope at night.  BTW - if the pinhole is too big the images will be grossly overexposed [white-out] eg beyond the range of the software's exposure limits.  Good luck.