My contribution
#2 - Tutup viewfinder semasa ambil lights, darks, flats, dark flats
Dengan menutup viewfinder kita dapat mengelakkan stray light daripada memasuki kamera dan mengenai sensor. Kita hanya mahu cahaya dari langit sahaja utk mengenai sensor, bukan dari sumber2 lain. Masa ambil gambar biasa no problem pasal mata kita akan menutupi viewfinder dan stray light tidak akan masuk tapi astrophotography biasanya kita tidak melihat melalui viewfinder. Kalau Canon EOS kita boleh guna viewfinder blocker yang diberikan sekali bersama strap.
Hi all,
1 cent from me:
About Dark Frames, Dark frames must be the same temperature and ISO setting as the light frames otherwise the "footprint" won't match. Don't fall into the mistaken belief that you can use the same master dark all year on different images. The reason for this is that as the camera ages, the chip and electronics changes ever so slightly and soon you'll be seeing gamma ray hits on your images. To get good quality images, take about ten darks either before or after taking your series of light frames and then combine them into a
"Master Dark" Dark frames can easily be done by simply covering the lens with the dust cover while slewing to the next object..You can take DSLR darks any time with the camera lens cap on in the obs or in the office as long as the temperature is similar, minimising
cosmic ray hits. DSLR darks tend to be more consistent and predictable due to the processing algorithms in the DSLR.
P/S: Take some attention on the words that I highlighted.
Regards,
Tommy
