Eric5DMarkIII wrote:
**剛想到一個問題, 36MP對於22MP同樣100%裁切相當於A7R的圖又被放大了1.6倍, 這種比較應該要怎麼做才對?
把 36MP down sample 去 22MP 再作比較。
Oversampling & averaging是signal processing的一常用去噪方法
pooklin wrote:
DXO 的ISO評分...(恕刪)
DXO 的ISO SCORE 定義如下:
" An SNR value of 30dB means excellent image quality. Thus low-light ISO is the highest ISO setting for a camera that allows it to achieve an SNR of 30dB while keeping a good dynamic range of 9 EVs and a color depth of 18bits.
A difference in low-light ISO of 25% represents 1/3 EV and is only slightly noticeable.
As cameras improve, low-light ISO will continuously increase, making this scale open. "
簡單來說，ISO三千多的時候，SNR或EV或COLOR_DEPTH已經跌穿規定值。
因此就算ISO6400,12800,25600時有比較好，也不會影響ISO SCORE.
對於DxO的評分方式本來不想再說,請看原說明:
http://www.dxomark.com/About/Sensor-scores
節錄:
Sensor Overall Score is normalized for a defined printing scenario—8Mpix printed on 8"x12" (20cmx30cm) at 300dpi resolution. Any other normalization, even at a higher resolution, would lead to the same ranking, given that any camera that could not deliver the chosen resolution would be eliminated from the comparison.
各自解釋了....
唐小見 wrote:
期待Eric大敲一下艾倫的通告
A7R真不是普通剽悍啊...(恕刪)
最後我實在無法忍受, 已經放棄500G換成428L2回Canon家的懷抱, 目前為止拍的很開心~ 這裡有很多艾倫和安娜, 來坐坐吧
【佳能砲開箱】400mm f/2.8L二代開箱
pooklin wrote:
DXO 的ISO評分...(恕刪)
ks_stone wrote:
感謝樓主無私的分享~...(恕刪)
那張鈔票有點皺而且我後來發現好像沒有貼的很平, 影響也許不大但晚點我找別的東西重拍一組再放上來看看.
fake802 wrote:
您的DPP轉raw Viewing and saving RAW images預設值有改為High Speed嗎？
沒的話，就不是真正沒抹過的raw。(恕刪)
我沒有用DPP和Sony的Image Converter處理兩家的RAW檔, 習慣都是直接用Bridge, Camera RAW和Photoshop作業, 雖然Camera RAW被蠻多人批評套用各家風格檔有問題(不過我沒這樣用...細節就不說了), 轉比較圖的時候銳化和除噪都是關掉的所以應該沒有影響結果.
內文搜尋
從 APP 打開
X