Rho Ophiuchus
Optics: Canon 135 mm f:2 L lens, Canon
200 mm f:2.8 L, Canon 400 f5.6 L.
Camera: Modified Baader Canon 350D (Halpha pass filter - see
here) at ISO800.
Mount: Takashi EM200. Processing : Iris
software. Observatory: Pic du Midi (altitude 2860 meters, french Pyrénées).
Rho Ophiuchus complex
The
red bright star is Antares (Alpha Sco)
Comparison
of the 135 mm and 200 mm images (full frame reduced by a factor four)
135
mm lens images: Stack of 14 x 180 seconds exposures at f/2.0 (full aperture).
July 23, 2006
200 mm lens images: Stack of 9 x 300 seconds at f/2.8 (full
aperture). July 25, 2006
The 135 mm lens images @
f/2.0
Scale
reduced by a factor two relative to the original.
The 200 mm lens images
@ F/2.8.
Original size
reduced by a factor two.
The 200 mm lens images
@ F/2.8.
Boost of the
contrast.
Download
the full-frame 200 mm images at the original size (7.3 Mb)
The 400 mm lens images
@ F/5.6.
Stack of 28 x
120 seconds exposures at ISO800. Original size reduced by a factor 4. July 27,
2006
Crop at the original scale
of the 400 mm lens images around the star HD147889 and the nebula IC4603.
Note
the improvement of the resolution compared to the 135 mm and 200 mm images.
Some IRAS source are visible (red stars).
