never used darks but will now

[iwols]

just taken a few darks and suprised how many bad pixels i have,this has been stretched quite a bit is this normal thanks

 

[Davey-T]

Bad pixel map will remove them.

Dave

[alan potts]

I have to say I am surprised by this, I though cooled cameras only had a very few. My 40d darks look like a war is going on.

[Robny]

16 minutes ago, alan potts said:

I have to say I am surprised by this, I though cooled cameras only had a very few. My 40d darks look like a war is going on.

I may be wrong but I think bad pixels are not related to the temperature of the sensor.  Read noise is where a cooled camera shines, bad pixels you'll find on most sensors.

As I said, could be wrong and I'm sure someone will say if I am ?

Rob

[alan potts]

2 hours ago, Robny said:

I may be wrong but I think bad pixels are not related to the temperature of the sensor.  Read noise is where a cooled camera shines, bad pixels you'll find on most sensors.

As I said, could be wrong and I'm sure someone will say if I am ?

Rob

It still looks like a war on my darks, I have no idea but I would have though bad pixels could happen on any sensor, I think what I am seeing on mine are hot pixels.

[Davey-T]

37 minutes ago, alan potts said:

It still looks like a war on my darks, I have no idea but I would have though bad pixels could happen on any sensor, I think what I am seeing on mine are hot pixels.

Hot pixels / dead pixels all bad pixels

Dave

[ollypenrice]

Don't judge a camera by its darks. My favourite camera's darks look like a snowstorm. The camera I have which gives the cleanest darks gives consistently the hardest data to process.

Olly

[iwols]

2 hours ago, ollypenrice said:

Don't judge a camera by its darks. My favourite camera's darks look like a snowstorm. The camera I have which gives the cleanest darks gives consistently the hardest data to process.

Olly

what is your favourite camera ollypenrice,the one im using is the atik 414ex,great little ccd

[ollypenrice]

7 hours ago, iwols said:

what is your favourite camera ollypenrice,the one im using is the atik 414ex,great little ccd

It's our Atik 11000 full frame camera. All the numbers are against it, 50% QE, lots of noise in the darks, but it just produces data you don't have to fight. Great star colour, clean background sky. My suspicion is that it's the well depth which makes it work so sweetly.

Olly

[Rush]

18 hours ago, iwols said:

just taken a few darks and suprised how many bad pixels i have,this has been stretched quite a bit is this normal thanks

 

 

This looks almost like a clean dark frame. My work horse CCD cams shower blizzard snowfstorm appearance through the wind shield.?

Especcially with Baader Ha filters. A cosmetic correction or a Bad pixel Map (like Dave wrote) will remove this. In my experience worst noisy Chips

like KAF 8300 still make pretty images. I agree with Ollys point do not judge cameras from the noise. Processing  noiseless cameras are not so easy. True.

CS

Rush