RAW files

[Radders]

I took some pictures last night in RAW with my Canon 700d which looked ok but when I tried to do a star trail picture it was just white. I put it onto bulb and set the intervalometer for 25 minutes. Is it because I didn't do continuous shooting? Should I have done 30 secs with an interval?

Paul

[Davey-T]

Do you mean you did one single 25 minute exposure ?

Do a seach on Y'Tube  for lot's of tutorials

Dave

[michael8554]

Your 25 minute exposure was white because even though it was at taken night, the camera gathered so much light it was completely over-exposed.

As Davey-T suggests, look at some tutorials, the exposures have to be long enough for the stars to trail appreciably, but mot enough to burn out the sky,.

Michael

[Radders]

Thanks guys. I've looked at tutorials but nothing about over exposed raw files.

[Davey-T]

Depending on other settings and sky conditions a 25min exposure will yield a white overexposed image, is it actually pure white, have you got some imaging software to measure pixel values ?

Dave

[Radders]

Yeah its pure white. I've probably messed up somewhere along the line

Paul

[Star Gazer]

Hi Paul

25 MINUTES is where you messed up. Next time try 25 SECONDS. Take 60 exposures, stack them in a suitable application and then you will have a beautiful equivalent 25 minute exposure - that isn't over exposed.

Good luck