昨晚拍的M42獵戶座大星雲，上面是自動增益，下面的手動調至最高，曝光從左至右依次是1、3、5、10、20、30分鐘。

憑使用兩個月下來的經驗，在普通天空下拍比較明亮目標，三五分鐘曝光已能把大部份細節拍下，十分鐘以上仍有好處，二三十分鏡以上增益輕微。

攝於星河科研社新界西基地，Seestar S50加外置Antlia QUAD band濾鏡，但不是必須，https://eshop.astro.hk/hk/catalogs/products/9084575a-a826-41d9-a8f3-0f04ef5fd2f3 

Last night, I captured images of the M42 Orion Nebula. At the top, automatic gain is used, and at the bottom, I manually adjusted to the highest setting. The exposure times, from left to right, are 1, 3, 5, 10, 20, and 30 minutes respectively.

Based on my experience from using this setup for 2 months, under ordinary skies and when photographing relatively bright targets, an exposure of three to five minutes already captures most details. Exposures beyond ten minutes still have benefits, but the gain beyond twenty to thirty minutes is minimal.

Taken at Galaxy Scientific Group New Territories West base, by Seestar S50 with an external Antlia QUAD band filter, but the filter is not essential, https://eshop.astro.hk/en/catalogs/products/9084575a-a826-41d9-a8f3-0f04ef5fd2f3