stacking narrow band in Deep sky stacker

[graham.hobart]

I took some H alpha and I tried to stack in DSS. Didn't work. I assume it's a star registry thing?. How do I do it?
Thanks
Graham.

[JohnH]

Sometimes alignment will fail if your frames have to few or (and I do not know why this is so but it is my experiance fwiw) too many stars identified.

You might try setting the threshold to get about 50 stars in your frames recognised. This is done on the Advanced tab of the Register Settings dialoag by changing the value from it default of 10% (lower - more stars - higher - less).

[graham.hobart]

Iv'e tried 1%, 2% 4%, 10% 50% and 89%- still no stacking ? What else can I try -(apart from manual stack in Nebulosity!)
I unticked box that says mono frames from OSC camera or dslr as it is neither.

[tlgerdes]

When you open individual frames in DSS, do you see the stars?

Is the HA from a mono or colour CCD?

[graham.hobart]

I see some stars, and the pics are from a mono CCD (atik) with a Ha filter.
Graham