Quote:
Originally Posted by Garbz
What filter did you use? .... I've seen some results of the triffid taken through LPR filters and the blue was almost non-existent.... How hard was it to colour correct your results as well?
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For the Lagoon and Triffid I used a Lumicon Deep Sky filter. It's a little more narrow band than the Astronomik CLS. The horsehead was mainly with the Lumicon also but M42 was a 50/50 sub mix of Lumicon Deep Sky and Baader Semi-Apo filter. The Semi-Apo is a combined Moon and Skyglow + Fringe Killer. It's a wide band filter designed to reduce CA in refractors and I think passes blues a little better than the Lumicon but doesn't reduce light pollution as effectively. It's so wide it can be left on for most objects, including star clusters and galaxies.
The colour shift of the Baader Semi-Apo is minimal, but I still use manual colour balance in the camera.
The colour balance shift with the Lumicon Deep Sky is stronger so I use camera and photoshop adjustments. In level adjustment it's just a single click with the middle eyedropper to get a neutral background. Well sometimes more than 1 click but it's not too bad.
If you want blues, do take note of the filter's spectral graph cutoff, especially at the shorter wavelengths around 440nm.
The Astronomik CLS should pass a little more blue than the Lumicon Deep Sky, but the UHC and UHC-E will clip blue more strongly.