Eskimo

[LT]

Hi,

Does the image below look like an Eskimo?

Taken through a 10"F4.7 Newtonian + ST-237 CCD camera + Vixen New Atlux mount in Yuen Long. No guiding, just auto tracked by the mount itself, and stacking of 40 frames of 20 sec. No LPS/narrow band filter. Image processed with Photoshop.

Comments are welcome.

LT

Image location:
http://astrofarm.no-ip.org/~album/share_image/5018.jpg

[jacky]

可不可以貼一張上來，我這邊看不到圖。多謝！

[Wah!]

好靚呀!
個seeing都好定!!!睇到流口水~

[Wah!]

今期APOD原來正好講呢個星雲呢!

[Wongsir]

Hi,

Does the image below look like an Eskimo?

Taken through a 10"F4.7 Newtonian + ST-237 CCD camera + Vixen New Atlux mount in Yuen Long. No guiding, just auto tracked by the mount itself, and stacking of 40 frames of 20 sec. No LPS/narrow band filter. Image processed with Photoshop.

Comments are welcome.

LT

Wah, 我鍾意LT呢張相,它極像一個有笑容的人面.
不過係唔係愛斯基摩人就唔太清楚.

Wongsir
8-12-2003

[WenXP]

個愛斯基摩人笑得好滑稽, 哈哈...
真係一幅好相.

[Wah!]

哈勃個張反而唔似愛斯機摩人笑臉呢!

[Subaru]

高手又出招, 勁!

[LT]

Hi Jacky,

Please send me a email so that I can contact you again to send this Eskimo image to you and to enquire about your newly discovered good site for deep sky shooting.

Thanks,

LT

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Hi Wah/anyone,

Could you tell me the method and which software of how to do subtraction on stacked image? Can Photoshop do the job well? Which version at least?

Thanks.

LT

[豆豸苗]

噢. 愛斯基摩人好 cute 啊. ^^

天上面真係多有趣0既野. 又有貓爪, 又有馬頭, 又有愛斯基摩人. ^^

[Wah!]

LT,你的subtraction是指dark frame subtraction嗎?
我的做法是用K3CCDTools(freeware)做呢個工作,而且是在每一張raw frame度做,唔係final stacked image度做.因為stack時是以feature來對位,但hotpixel可能因為追蹤誤差走位,stack完都會模糊,呢個時候做darkframe subtraction都無用.即使追蹤極準,subtraction完就會出現左個0,0,0的全黑點.
至於Photoshop,可以用layer的"difference"功能來模擬darkframe subtraction.