Thank you for attention, Atalas, Justin and Marc.
No Justin, I am not using coma corrector, nor any filter and nor guiding. Not yet !
I am not sure if I will buy another better camera and filter wheel. So I am waiting for thi$ deci$ion !
Because this I am trying more total exposure time.
Critical is repeat the same angle position of the camera every day.
Now, I will try any nebula. Two or four days, to get some hours of data.