FS: Astronomic Canon EOS Clip-Filter CLS-CCD [Sold]

[willis]

Just like new. Used once only. HK$1300
MTR Tseung Kwan O Line

viewtopic.php?f=17&t=380

List of compatible Canon EOS cameras
http://www.astronomik.com/en/eos_clip-filters.html

[社長]

如有中國內地(或海外)同好有興趣，本人可義務代交收貨/款。

人民幣為1170，空郵掛號20元，可以匯款至廣州工行。

台幣及東南亞等同好可以Paypal支付。

[Nebulas]

好价钱，Willis考虑升级设备了？

[willis]

好价钱，Willis考虑升级设备了？

Not really upgrade, but want to try something new....

[Nebulas]

好价钱，Willis考虑升级设备了？

Not really upgrade, but want to try something new....

如果是摄影发烧友第一时间看到这个信息，肯定第一时间就抢了。

[Henry Wu]

是否可請說明此　Filter 的功效　　
謝謝

[willis]

是否可請說明此　Filter 的功效　　
謝謝

I tried both CLS & P2. The P2 is not owned by me. I found that CLS has stronger light pollution reduction power. Both filters block the annoying Na light (589.0 and 589.6 nm) http://en.wikipedia.org/wiki/Sodium-vapor_lamp. However, the CLS blocks yellow (around 570-590 nm) completely in the spectrum which make it impossible to image those DSO with yellow http://en.wikipedia.org/wiki/Visible_spectrum. Although there are not much DSO with yellow, Rho Ophiuchi Nebula 星空調色盤 is one of those and is my favor. As u can see from my Ophiuchi Nebula photo, I cannot process out the natural color of Rho Ophiuchi Nebula. This frustrated me a lot. On the other hand P2 block only the annoying Na yellow lines and allow some yellow to pass. So P2 helps a lot in this situation. Well if u have enough money, it is always good to have both. As I mentioned, not many DSOs with yellow, CLS is useful in heavily light polluted area. While P2 is a moderate light pollution filter which enable some yellow to pass.
See these links for the spectrum response of CLS & P2:
http://www.astronomik.com/en/cls/astron ... s_full.png
http://www.teleskop-express.de/shop/Bil ... transm.gif