AltairAstro 269c PRO TEC Gain settings

[bluemoonjim]

hi
I have recently been in contact with Altair Astro regarding sensor analysis read out for my 269c pro tec camera which shows the noise 'drop' occurring around gain 2000 rather than around 200, which was the expected figure according to info on the Altair Astro and TS Optics websites. The following is the reply from AltairAstro tech support:
....It would help to run through the various settings and with SharpCap technical support as there are "gain autoswitch points" for each camera built into the software and settings must be correct for it to work. You can also try using HCG and Ultra mode switched on and asking SharpCap for advice on their latest version as to where the "gain autoswitch level" is for this camera. Also try using the ASCOM driver to compare.
I have now read a similar message on this forum about the sensor analysis and have seen your reasons for the gain settings appearing as they do on the graph. Is this something you might revisit in future updates of SharpCap?
Kind regards
John

[admin]

Hi,

this was a deliberate decision on my part - when I tested out the 269C, there was a significant amount of banding noise visible in HCG mode (and not in LCG mode). My impression was that this, combined with the fact that the read noise drop from changing to HCG is smaller on the 269 sensor than on other models, meant that best results were likely to be obtained on LCG.

I have just had a chat with Altair and they say that the camera circuitry has been tweaked to deal with the banding noise issue since the early pre-production model I had, so I can change the code in SharpCap to alter the HCG start point.

cheers,

Robin

[bluemoonjim]

Thank you for the quick response Robin and for your great work with SharpCap.
All the best
John