Playing with CCD's

[Earl]

just about to play with my first ever CCD imaging using my QHY6.

This will be messy LOL

[Earl]

And here it is.

[riklaunim]

And it works nicely . You probably noticed the horizontal lines - that's from interlaced shutter of the CCD. To avoid them you may not use very short exposures and avoid shaky coditions when imaging. Also some software (like Nebulosity) has "deinterlace" options to smooth those lines out.

[Earl]

a little more playing 300s

[msinclairinork]

Not messy at all Earl!

Great test for your first CCD!

Looking forward to seeing many more!

Michael

[Earl]

It was interesting using the scope with CCD's for alignment and just the 9 x 50 finder

Once focus was sorted everything went well.

One interesting point I found out was using 1 second exposure on each camera the DMK21 was far more sensitive than the QHY6

[riklaunim]

One interesting point I found out was using 1 second exposure on each camera the DMK21 was far more sensitive than the QHY6

Well, that's gain differences you see, not sensitivity. The DMK21 as a 8-bit industry camera has high gain. QHY6 as a 16-bit camera will have much lower gain (and having also more sensitive CCD). For planetary imaging very short exposures are essential (high gain helps), for DS - high dynamic range and low noise (low "optimal" gain required).

With a 8-bit DMK you would catch only brightests parts of the M57. Longer exposures would overburn it and in general prevent from catching the fain parts of the nebula. If you would lower DMK gain and increase the exposure time - it would be better, but not as good as 16-bit high dynamic range camera, that if using long enough exposures would be able to catch 65535 shades - from bright to dark. DMK can use only 255 shades for the same thing

http://lawoflaws.com/pl_images/Ring_Nebulae.jpg - thats the advantage of true DS cameras over "planetary" cameras

[Earl]

Well, that's gain differences you see, not sensitivity. The DMK21 as a 8-bit industry camera has high gain. QHY6 as a 16-bit camera will have much lower gain (and having also more sensitive CCD). For planetary imaging very short exposures are essential (high gain helps), for DS - high dynamic range and low noise (low "optimal" gain required).

With a 8-bit DMK you would catch only brightests parts of the M57. Longer exposures would overburn it and in general prevent from catching the fain parts of the nebula. If you would lower DMK gain and increase the exposure time - it would be better, but not as good as 16-bit high dynamic range camera, that if using long enough exposures would be able to catch 65535 shades - from bright to dark. DMK can use only 255 shades for the same thing

http://lawoflaws.com/pl_images/Ring_Nebulae.jpg - thats the advantage of true DS cameras over "planetary" cameras

Ah I see, I was switching between the two in PHD to see how they compared.

The images were taken with the QHY6, I did find that the DMK showed far more visible stars in PHD.