Bangkok Night Lights at the end of 2007 with Canon EF-S 10-22 USM

I've got Canon EF-S 10-22 at the end of last year. It's an ultra-wide lense with aperture 3.5-4.5
The most sharp is around 5.6 - 8
I used this lens when i go to central world plaza @ Rajaprasong junction. They always using million of lights for new year celebration.

The 1st picture is in Central World Plaza.

My Canon Lens EF 70-200 F4L IS

Overview

The EF 70-200mm f/4L IS USM is a lightweight, compact L (Luxury) Series telephoto zoom lens with an IS (Image Stabilizer). The IS is new generation IS that help you up to an incredible four stops of shake correction. The IS may help you take a picture at 200mm. with 1/12.5 s. of speed shutter but in my real life experience with Canon 40D, i take a 200mm. (~320mm on APC-S sensor size ) photo with 1/40 s. and the result is fairly sharp. Same as most of L Lens, Canon put the fluorite UD lens elements to provides excellent optical performance in terms of resolution and contrast. And also with its water-and dust-proof construction, provide both the performance and portability to meet user demands. The USM ( Ultra Sonic Motor ) is extremely quiet and fast to focus, Even in low light condition. And it contains Full-time Manual Focus mean you can shift focus manually.

I bough this lens in Thailand for about 1,200 $ US with 1 year international warranty plus additional 1 year local warranty. And this lens is my most favourite when i take a portrait photo. Yes, it's quite expensive, but i think this lens worths it cost.

Specification

Marketed : November 2006
Original Price : 158,000 yen
Lens Construction (group) : 15
Lens Construction (element) : 20
No. of Diaphragm Blades : 8(circular aperture)
Minimum Aperture : F32
Closest Focusing Distance (m) : 1.2
Maximum Magnifcation (x) : 0.21
Filter Diameter (mm) : 67
Maximum Diameter x Length (mm) : 76 x 172
Weight (g) : 760

Reference of the specification : http://www.canon.com/camera-museum/camera/lens/ef/data/telephoto_zoom/2006_ef_70-200_f1.4l_is_usm.html

How IS can help you?

Canon Technology hall ( in Canon Camera Museum ) can explain how IS work better than me
Please see that http://www.canon.com/camera-http://www.canon.com/camera-museum/tech/room/f_index.html

Compare with Canon EF 70-200 F2.8L IS
The 2.8 F-Stop is faster than F4 for 1 stop. It can help you to stop motion of subject ( or camera shaking ) but EF 70-200 F2.8 L IS is double cost of 70-200 F4L IS and also double weight. That's why i picked an F4 IS instead.

And many photographers said F4IS is sharper than F2.8IS but i'm not confirmed that. :)