SharpCap Forums

Hi All

I've used SharpCap to perform a sensor analysis of my Altair 183C Pro (fan cooled) camera and, if I'm interpreting it correctly, I think that the optimum gain is 400 (I may be wrong here so, please, if you have the correct optimum for this camera feel free to correct me).

My question is, if the optimum gain is 400 in SharpCap, is this gain value I would use in NINA? I'm sure I've seen discussions somwehere about different imaging software using different scales to measure gain values. VHS and Betamax spring to mind here (If you don't get this, you are not of a certain age )

Thanks in advance.

Hi Richard,

oh yes, I remember betamax (we had one at one point...)

The difference arises when a camera has multiple gain modes (often called LCG and HCG - low conversion gain and high conversion gain). SharpCap merges these into the main gain control, switching automatically between the modes in a way that gives the best results whereas other software display these as separate options in addition to the gain control. Note that ZWO cameras take the merged in approach for all software (they hide the LCG/HCG switchover from application authors too).

In the case of your 183, that camera doesn't have LCG and HCG modes, so the gain values you see in SharpCap should match those in other software. For Altair cameras, the gain starts from a minumum of 100 and you can work out how much brighter it is by dividing the gain value by the minimum of 100 - ie gain 900 is 9x brighter than gain 100. Some software may display gain starting at 1 for Altair cameras, in which case gain 9 is 9x brighter...

Hope that makes sense,

cheers,

Robin

Hi Robin

So if SharpCap indicates that a gain of 400 is optimal for the 183C then this is what I should set in NINA? I guess that, in line with other aspects of pursuing astro imaging, it wouldn't hurt to try a few different settings

Glad that not all those who remember VHS and Betamax have departed yet. Now, where did I put my 8 track player?........

Thanks for replying so quickly.

Cheers
Richard