Investigate LC shutter malfunction

From DFN Wiki
Jump to: navigation, search

Ways of checking if the LC shutter works or not


A first step that can be remotely done is checking that the LC shutter is doing anything at all by looking at the pictures.

Every top of the UTC hour + 30" and half hour + 30", the camera takes an astrometric calibration picture with the LC shutter fully open (to expose the stars more).

The general brightness of the image should change drastically.

Check the difference in brightness between an image taken around HH:00:30 (a typical filename is  033_2018-12-25_190030_E_DSC_0181.NEF, but the timestamp part could anything close like 190027, 190028, 190029, 190030, 190031, 190032), and the next image.

Obviously meteors captured at these times would not display any breaks.

On site visually

The LC shutter runs all the time (even during the day), and its frequency (10/20Hz) makes it just about perceptible by the human eye.

- Open the DSLR eyelet and use an inspection mirror to check if it is flickering through the eyelet.

- (a bit harder to distinguish) looking straight down the sunlit lens (or with a torch if at night time), you should also see it flicker, but it is harder to spot.


- A common fixable issue is the LC cable is disconnected from the PCB. This link can help to know what to look out for:

- Check for damage on the cable up to where it is glued onto the lens.