Add CMOS GAIN to Event Parameters


I have purchased Version 3 and installed it. The new Target Planning Tools are very nice, and will certainly be useful. I was hoping to see the CMOS GAIN parameter added to the target event table. It is the only option available in the Event Settings that has a high probability of requiring a value on every event, and as such, should be included with the other parameters that can be directly set on the Sequence dialog within the Event table.

Having worked only with CMOS cameras for the past year, I have found that it is an enormous pain in the rear to have the gain hidden within the gear icon, and further within the Settings option. CMOS cameras have become a major player in the camera field. It would not surprise me if more of them are now being sold than CCDs.

This difficulty is further exacerbated by the fact that if the defined gain in the driver is X, and any single event sets it to Y, then it remains Y forever. This screwed up my first night of imaging using this feature, since I assumed if it was not set, it would use the default value. At least making it work by always using the default if not explicitly set would be a big improvement over the current protocol. As is, I almost always don’t use it at all because of the uncertainty as to what gain is actually set for each event.

Implementation suggestion:
Use some or all of the progress bar to display GAIN. While you are at it, why not display some icon to indicate that one of the other hidden event settings is actually activated. I personally have never used any of the event settings available there, but if I did, I would love to see an icon displayed in the event table to let me know that that event has a special feature enabled. In fact, a set of 2 letter codes could be used to indicate which feature was turned on. 1st letter indicates pre/post, second letter which feature.


Another vote to add gain to the list of event parameters. I was expecting to see gain listed with the other event parameters. So if event gain says “Not set” it will not used what is in the equipment profile?


I agree with this one. It’s very very easy to miss the gain parameter when it’s not on the main screen.


Another vote to expose the gain setting as part of the main event window. I suspect this may require enlarging the sequencer window a little.

This is not true of all cameras and depends on the manufacturer. With my QHY163M I can set the gain in SGP per event and it does not change the setting in the ASCOM driver settings. So to use your example, if the defined gain in the driver is X, it stays X forever until I change it in the driver.


This is also true for my ASI1600MM, and is exactly what I would want to have happen. The gain setting in the driver should never be changed by SGP, which would only change the gain being used for each event. This assumes that SGP can use an arbitrary gain value for an image capture without changing the gain that is set in the driver, which is apparently true based on how it has behaved for me.

So the change I am proposing is that SGP use the gain setting in the driver for every event that does not have its own gain value set.


I must not be understanding something correctly. This is exactly what my QHY163 does. If I do not define the gain in the SGP event settings, the image exposure will revert to the driver gain.

So let’s say that my driver gain is set at 200, and my normal gain for LRGB images is 75. I create a LRGB sequence and I set the LRG events to gain 75, but I forget to change the B event gain (so it stays as ‘not set’). Therefore, all my B exposures will be at gain 200 instead of gain 75.

What am I missing?


That is exactly what I want it to do for me, but it is not.
Here is what happened with my ASI1600:
Driver gain set at 200.
When it starts a sequence, all initial events with no gain set, correctly use the gain I have set in the driver, 200.
Now it gets to one or more events with gain set to 75, it uses 75 for them.
Now some events follow with no gain set, it continues to use 75.

This, BTW is how it is documented to behave.
Maybe this varies depending on the driver.


I see. I’ll have to double check the behavior of my camera some time but I was sure it worked like I described above.

In any event, having the gain exposed on the main event line would be super. :grinning: