Can't take flats for toffee!

[Spoon]

Hi everyone,

Just a quick one: I can't take flats to save my life which means my images are cropped massively therefore extremely noisy. I use a canon 1000D modded against a white laptop screen. Can anyone suggest a time for the frames? I read about ADU? What number should this be and where can you see this number?

Thanks

Cam

Sent from my iPad using Tapatalk

[red dwalf]

You could also use the histogram, the histogram peak somewhere around the third to half way along the graph.

[carastro]

People tend to talk about ADU for taking fits files.  The subs from the Canon DSLR will be RAW files.

For a DSLR you need 100 iso and AV settings and the white screen shouldn't be bright, just a dull even light.  Do not move the orientation or focus of your camera before taking your flats.

Look at the histogram and trying to get the peak between 1/3 from the left and halfway.  You can view this on Digital photo professional (part of the Canon Utility software).  If the flats are over-exposed they won't work.

HTH

Carole

[Nathan_Pembs]

Some good info there Carole, from what you've said my flats must be too bright.

Would explain why they don't usually work very well

[Spoon]

Some good info there Carole, from what you've said my flats must be too bright.

Would explain why they don't usually work very well

I know the feeling mate haha

Cam.

[carastro]

Carole, from what you've said my flats must be too bright.

Would explain why they don't usually work very well   

I am speaking form personal experience lol, as I over-exposed my flats when i first started and wondered why they didn't seem to work.  Luckily some kind soul pointed me in the right direction.

Carole