[Obi-Wan]

http://dc.watch.impress.co.jp/docs/review/longterm/20090911_315027.html

The low noise winner @ high ISO is ===> 50D

[10099644]

Obi-Wan兄你好似對50D好滿意喎,^^ 我都係用50D 就算上FF我都會Keep 返50D影動態相 ,部50D我都唔會賣.

[Obi-Wan]

10099644
yes 50D is a very good responsive camera, I bought 2 50D (one water, one hong), my 5D2 is left at home with 17-40 together in the dry cabin.
I usually use 50D+10-22 or 50D+18-200

[wesleyyau]

Obi-Wan兄你好似對50D好滿意喎,^^ 我都係用50D 就算上FF我都會Keep 返50D影動態相 ,部50D我都唔會賣.
========================================================
我都係咁諗... 除非過o左n 年後轉二手7D2先會放50D... 真係n 年之後... :P
不過可能一上FF 就走哂D EF-S... 養兩SET 唔係好抵... =D

[Obi-Wan]

wesleyyau
^_^
I also 養 some nikon, some olympus, some sony too, all my $ used for these babies

[onjo3]

hi, Obi,
may i ask,
if the mega pixel is higher on same body,
is it always better in noise control??
coz my 5d compared with 5d 2,
after cropped, the image noise is much strong than 5d2,
of coz the cropped image size are different becoz 5d 2 is much high mega pixel.
i wanna know the "difference" i saw, is just becoz the mega pixels different,
or noise control grade??
would mega pixel effect that??
thx for help.

[kw7559]

50d真係可以用多好多年,極力推介!!
40d都差幾遠下,但係就超級勁慳電,想放,不過價太低啦,留返自用或者送比朋友好過

[Obi-Wan]

onjo3 very good questions!
****************
"if the mega pixel is higher on same body,
is it always better in noise control??
coz my 5d compared with 5d 2,
after cropped, the image noise is much strong than 5d2,
of coz the cropped image size are different becoz 5d 2 is much high mega pixel.
i wanna know the "difference" i saw, is just becoz the mega pixels different,
or noise control grade??
would mega pixel effect that??
thx for help. "
*****************

Obi-wan's answer:

In principle the the higher pixel density (no. of pixels per unit area), the higher is the noise

5D (12.8 million effective pixels /(35.8 x 23.9 mm2) = 15000 pixels /mm2 = 1.5MP per cm2
5D2 (21.1 million effective pixels /(36 x 24 mm2) = 24421 pixels/mm2 =
2.4MP per cm2

The 5D2 should have higher noise than 5D, THIS IS NOT TRUE!

There ARE another factorS:

1. the gap between microlenses above the pixel sensor. The gap is larger in the case of 5D. As pointed out in 5D2 white papers from CANON, they have reduced the gap between microlenses above pixel sensor, therefore the each pixel sensor sense MORE light than expected, therefore the difference between the pixel densities of 5D & 5D2 does not affect much on the light collected by the sensor.

(in short, the CMOS of 5D2 have pushed the high signal to noise level to the highest)

This part is easy to understand. The following are more complicated.

2. The anti-alias filter of 5D is different from 5D2

(in short terms, the anti-alias filter of 5D2 can resolve more details YET does not increase much noise)

3. The noise reduction algorithm (not disclosed by canon, the most secret!), in fact your 5D2 21.1 MP are NOT all used to collect the same light (as visible light is not monochromatic) your 21.1MP sensor is in fact a 10.55MP green pixel sensor, 5.275MP red & 5.275MP blue pixel sensor => If u use your 5D2 to capture black-white image under just monochromatic RED light, the resolution is just 5.275MP. The DSLR designer use different algorithm to generate the complete full color 21.1MP image. This explain why Sony A900 & Nikon D3X use more or less the same sensor, yet Nikon can do much better in noise reduction than sony (which produced the same sensor!).

*** this part can be further improved by firmware upgrade, e.g. can remove the banding of 5D2 @ ISO25600

(in short terms, the noise reduction algorithm using the production of the full color 21.1MP image SUCCESSFULLY REDUCED "chroma" noise which is more obvious)

4. The noise reduction circuit (not disclosed by canon, the most secret!), the best noise reduction circuit is still produced by canon, the technology is still advancing. How the noise reduction circuit works is out of my knowledge, but may involve "take-more-sample-and-average them in the short times". The DIGIT 4 proves successfully reducing the noise of 5D2, 50D etc.

(in short terms, the noise reduction circuit successfully mimic an increase in signal to noise level)

SORRY for the lengthy explanations, hope all you guys understand. If not, just enjoy the high technology of 5D2 & shoot shoot shoot.

HAPPY SHOOTING!

[wesleyyau]

obi-wan 兄..
你就好啦... 可以可以有咁多babies...
我d 錢好多去o左養我老婆D babies... LX,GUXXI,XPHONE,etc...
唔係d 股仔生性... 我50D 都分分鐘冇得用... ~>.<~

[wesleyyau]

當然老婆仔開心緊要... 定係我買幾支L 開心緊要... 我都係prefer 前者... :p

[Obi-Wan]

wesleyyau

Many of the babies are gift from my students and friends, e.g. a student just give an old Tamron 70-300 zoom for Sony. I just pay him $500 for the lens, but he refused to take the $, he said he borrow this lens to me. BUT I don't think he will take it back as he bought Sony 70-400/4-5.6 G SSM

I am waiting for a students who dislike small small white IS & sell to me. (I just have SSW, SW, SWIS, but no SWIS)

^_^

[Ref54]

I like 50D too.

[火Ken]

我覺得 KW7559 C hing 都啱，我買左5D2後，40D太賤價，所以留番比自己用，其實有個Trade 40D換50D，但回想40D成萬蚊入手，而且好似嘥錢咁，算~ 自用！

[Marksman01]

火Ken, if I were you I will sell the 40D to fund a lens for the 5D2. If a 2nd body is necessary, the 7D of cos.

Keep spending money .....

[wesleyyau]

7D 當然係好... 但係依家d機價跌得咁快...
自己有50D 仲投資萬二蚊落APS-C... 當你二手50D賣到6800, 一手7D 12800... 如果$6000 對自己係細數目就冇問題... 如果唔係... 用o黎買鏡好過... :p
依家睇50D 同7D 距離可能覺得抵... 一陣出部60D DIGIC V... 有7D 八九成賣8K幾... 又可能覺得7D 唔太抵... 所有都係心理問題...
用50D又好40D又好... 操熟自己D 機/鏡... 都會影得開心... ^^