Effect of astronomical filters - 02 May 2008

Test picture of NGC 7000 - no filter, UHC-S filter(Baader) and H alfa pass filter (Baader). This is result.

This picture is only converted from RAW format. It shows real untouched view of digital camera LCD. From left: no filter, UHC Baader filter, H alfa passfilter 45nm. For each frame was used 180s exposure at 1600 ISO with the same lenses.

Next picture has set up only histogram.

And the result? Each filter changes color of picture. Size of stars is smaller with using filter. But on the other hand using these filters allows to elongate the exposure time and it allows to catch better dark parts of nebulaes.
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