[Astrofest] Antares, Rho Ophiuchi, and Blue Horsehead
Another from Astrofest taken with the 5DII and 135L. Without a doubt, the most colourful region in the night sky. Never imaged this area, always wanted to. It was the main target I was chasing this time at Astrofest.
Loving this 5DII and 135L combo. At first I wasn't liking the diffraction spikes, but I'm starting to forgive that considering the tightness of the stars across the full frame sensor. Only complaint is a very slight vignetting that I couldn't get rid of even with flats.
Chris - this focal length is very forgiving of less than perfect guiding, so it's not super-important as long as you're doing it. But since you asked, mount was an EM-200, guide scope was an Orion finder guider, and guide cam was a QHY5.
Thanks again, guys. I am extremely happy with my bag of images this time around. Enjoying processing them all.
Rick - in some ways it was a good thing, as it forced me to rethink what I was going to shoot and how I was going to do it. I ended up going for dark and reflection nebulae instead of emission nebulae, bigger targets etc.
Well done Troy. The combination of Rho and the blue horse head togethers makes for a really nice looking image. If it were me I might boost the saturation just a little, but other than that the full res shot looks great. Lovely image.
If you want to get rid of diffraction spikes due to the iris just put an aperture in front of the lens and shoot wide open. This will also limit the light NOT contributing to the actual image and being scattered inside the lens. This light reduces contrast and thus signal to noise.
It is a dark secret but the pixels at the corners of a full frame camera with 'fast' optics do not record all the incident photons due to their obliquity to the sensor surface. The micro lenses help but they just cannot work at 100% above a critical incidence angle.
