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GARMIN EPIX Pro Long-Term Usage Review

On June 17, 2024, I purchased a new Garmin EPIX Pro Gen2 47mm from PChome. The decision to buy was primarily due to the incredible price drop. Originally priced at 32,990 NTD, it was now available for only 22,180 NTD, a discount of over 10,000 NTD, making it irresistible. Although my previous Garmin vivoactive 3 Music was still functional, except for needing a charge every four days, this huge discount was too tempting to pass up. When I first got the vivoactive 3 Music, I was impressed with its design and functionality. It not only provided excellent Bluetooth headphone music playback but also offered comprehensive activity tracking and health monitoring. Its stylish design, comfortable wear, and intuitive user interface made it an essential device in my daily life. Whether running or hiking, the vivoactive 3 Music accurately recorded my exercise data and provided detailed analysis reports to help me better manage my health. However, technology is constantly evolving, and new sm...

何謂ISO?

這篇文章要談的是相機的感光度(ISO),如果你要找的是國際認證標準ISO 9001請你迴轉。
ISO值,也稱為ASA,ISO值是底片的感光度,數值越大感光度越高,可以在昏暗的場景中提高拍照的成功率。雖然現在數位相機發達的時代,仍然保留了ISO的調整參數,比起以前方便的是,在過去底片一旦裝上相機是不能隨時更改ISO值,除非換底片,而數位相機可以隨時依照環境來調整ISO值。

ISO和快門的關係

ISO越高,快門的速度就可以越快,什麼情況下會用到高ISO值?例如我去屏東海生館看餵食秀,室內光線非常昏暗,又不准開閃光燈,這時候唯有提高ISO值才能增加快門速度,拍到清楚的魚,如果快門太低就只能拍到魚游過的殘影。ISO的大小可以用一個簡單的方式來決定,在光圈先決Av的模式下,半按快門來測得快門速度,如果低於1/60秒就提高ISO值。以上方法只是一個參考,實際上仍然要取決於被攝物體的移動速度來調整快門,再依照需要的快門來調整ISO。

ISO和雜訊的關係

開玩笑的說高ISO所產生的雜訊和付出的錢成反比,付出的價錢越高雜訊越少,高級相機的雜訊會比較少。
為了提高感光度,底片上會加粗顆粒,讓底片紀錄更多的光線訊號,事實上也會記錄到光線的雜訊,因此高ISO的底片拍出來的效果解析度較低,雜訊較多。數位相機用的是同一塊感光原件,將感光原件所接收的光訊號放大來提高感光度,訊號放大的過程會因電子零件的溫度或其他零件的狀況而產生雜訊,電子零件用料越高級成本就越高,但是雜訊越少。

雜訊和感光原件尺寸的關係

在同樣畫素的相機中,較大的感光原件的每一像素就越大,可接收到更多的光線,雜訊在光線訊號中的比率較小,簡單來說感光原件越大畫質可以接受的ISO就越高,以單眼相機來說ISO400仍然不會出現明顯雜訊。
感光原件的尺寸:單眼相機>消費級相機>手機
雜訊:手機>消費級相機>單眼相機

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