FLI ML8300 Mono

[Ags]

Due to the great generosity of an SGL member, I am getting an FLI ML8300 Mono camera. I will be using the camera for a variety of things, including spectroscopy and photometry, but will also try to make pretty pictures (but don't hold your breath...).I have never had a cooled camera, a CCD, an astro camera with a physical shutter or one which needs a substantial power supply. I recall that these KAF 8300 chip cameras were quite desirable back in the day, one of the last hurrahs of CCDs? I am just wondering if any former 8300 owners have any tips to share? I have a vague idea that CCDs like fewer longer exposures in contrast of CMOS which work better with shorter, more numerous exposures?

Edited February 8 by Ags

[tomato]

That is a fine Astro camera you will be acquiring, it’s a premium brand version of this venerable CCD sensor, I have the Moravian Instruments version. I took 5 minute exposures for LRGB imaging and twice that or longer for narrow band. You will need to take flats, darks and Bias frames to calibrate your subs, and use the cooler as CCDs are inherently more noisy than the CMOS sensors. Having said that, there are a host of APODs out there captured with these cameras.

Here is a mosaic of M31 captured with my KF 8300 camera:

 

[Ags]

I guess with set point cooling I just shoot the darks and bias once. What temperature should I aim for? As low as possible, or low enough to reach the set point on any given night, but not lower?

[Adam J]

The rate of tech improvement in sensors is actually not as steep as some make out. After all you can only make things so good before [removed word] noise and LP are the limitations. As a result these older sensors are often underrated by the community. Someone who knows what they are doing with such a camera will put image someone with a new 2600mm used by an inexperienced imager. 

[Ags]

Yes, that was my thinking too, a camera that was raved about only a few years ago and which produced great images doesn't suddenly stop being good... The sensor is 3x times larger than my main camera (ASI485MC), which does have advantages, although I guess I will have to be more careful about spacing between the bigger sensor and any flattener. 

[windjammer]

My understanding is that CMOS sensors are more noisy than CCDs, at least in their earlier incarnations.  Hence the more and shorter exposures strategy for cmos, but I am not sure if that still holds.  The state of the art moves on. My CCD cam is an Atik 460, a very low noise, linear light bucket  also getting long in the tooth.  Full well is around 17k e- so at 16 bit is well sampled.  There is no gain control required - everything can be done in software after the event. I run at -10C summer and winter, it will run at a  lower temperature but imho the difference is marginal.  The trade-off between number of exposures and length of exposure given limited observing time is one point on which I am undecided.  In practice I choose exposure length so that the light pollution floor is just apparent (no pixels with zero count on the histogram) and accept saturation of the highlights (the brighter stars in the fov, which can be fixed in processing).  And the more exposures the better of course.  Having a library of darks (renewed annually) is pretty much essential, but biases I take every time - the time required is so short that one might as well as not.

The point regarding the improvement in sensors is well made.  The last generation of CCDs was very good indeed, so your KAF8300 should be competitive.  The main improvement with CMOS is number of pixels, sensor area and high speed USB3 readout.  And cost.  

Image processing s/w has improved massively, sophisticated algos available at the click of a mouse - IMHO that has been the real revolution: most of my investment has been in that area the last couple of years.

Good luck with your new cam!

Simon