Hi Jerry,
Thanks for the
reply!!
<Without the filter I went 15 minutes and with the filter I had to
go 3x as
<long (45minutes) to get the same density of the sky
background.
< So you should
<expose a lot more with the filter, I
would guess a minimum of 90 to 120
<minutes.
Oh boy, that's going to be a LONG manual guide...whew!
<It does
give a slight magenta cast which is easy to correct in Photoshop.
Okay, I just wanted to make sure it was the filter and not something
else.
<You don't say if all 4 of the images on that page were shot
with the same
<optical system.
The top 2 images were at PF and the bottom 2 were with my 105mm
lens. I haven't really noticed the unfocused looking stars with the 105
or 55 mm but it is very obvious at PF (480mm @ f6).
<Ain't astrophotography fun? ! :-)
Oh yeah!!
Thank you very much!! You've helped a whole
lot.