red fringing on bright stars after DSLR mod

[lensman57]

This is expected. Now you have extra sensitivity to red combined with a less than perfect lens for AP. Combine the CA and the red and you end up with magenta around the stars. It can be minimised with  critcal focusing but will not totally go away. You should also consider that a DSLR has a very shallow well depth so it gets saturated quite a lot earlier than a CCD, with stars what this means is the colour then bleeds to the surronding pixelx as the core of the star is saturated to white and this adds to the problem. I'd rather have a modded DSLR anyday to an un modded one.

A.G

[mindburner]

This is expected. Now you have extra sensitivity to red combined with a less than perfect lens for AP. Combine the CA and the red and you end up with magenta around the stars. It can be minimised with  critcal focusing but will not totally go away. You should also consider that a DSLR has a very shallow well depth so it gets saturated quite a lot earlier than a CCD, with stars what this means is the colour then bleeds to the surronding pixelx as the core of the star is saturated to white and this adds to the problem. I'd rather have a modded DSLR anyday to an un modded one.

A.G

thanks for this. Yes I think this combination of factors add to the problem. I do think I will make good use of the modded camera with my refractor (which may of may not be better) once the darker nights come in. M42 and friends on the target list for sure. I also have recently acquired a 200mm f2.8 lens which again is worth trying although may show similar results to the 50mm

[lensman57]

ncy was very poor

thanks for this. Yes I think this combination of factors add to the problem. I do think I will make good use of the modded camera with my refractor (which may of may not be better) once the darker nights come in. M42 and friends on the target list for sure. I also have recently acquired a 200mm f2.8 lens which again is worth trying although may show similar results to the 50mm

I just came back from a two weeks break in the south west Spain and for fun I had taken my 15X70 Binos. On a few occassions that I could not sleep I explored the sky and was shocked that I could see M42 at about 4am in all its glory, I also found M45, M13, M31, M33 and I am sure that I saw the Veil complex in Cygnus and the starfields of Sagittarius, the only shame was that for some reason the transparency was very poor due to either haze or mist.

Regards,

A.G