We use an image-analysis application called lmatest PRO (www.imatest.com)
to test the resolution of the lenses. Photos of specially designed test charts are taken in controlled and consistent conditions at range of focal lengths apertures. These are analyzed for sharpness at the center and edge. the average of these two figures is used to final resolution figure.
Resolution is quoted in 'line widths/picture height': the number of lines that can be resolved within the height of the picture. this is different to lines per millimeter figures because they only apply to a single negative size format typically 35mm. Digital cameras have different sensor sizes which mean different enlargement ratios for print hence different 'lpm' requirements for lenses.
Lenses dont just stop resolving progressively finer detail- they resolve it at lower and lower contrast. in the past photographers have disagreed about when detail becomes too soft to count. lmatest gets round this by using modulation transfer frequency MTF analysis and can define a cut-off point for resolution. this is called MTF50 or the point where the contrast falls to 50% the resolution figures are also dependent on the camera used. Different SLR have different resolution, different strength low-pass anti moire filters over the sensor and different processing and sharpening algorithms.
Saturday, September 12, 2009
Friday, September 11, 2009
5D MARK II PROS and CONS
CANON EOS 5D MARK II
Pros - Best performance at high ISO's with top sensitivity of iso 25,600 two stops higher than other DSLR. with 30fps 1080P HD video capture. Canon EF 24-105mm f/4 IS is the best kit lens you can buy for full frame. 9.9 megapixel sRaw1 and 5.2 megapixel sRAW2 formats allow full 14 bit postprocessing flexibility you dont need full 21 megapixel resolution. Live View is superior in convenience to D3X's includes Face Detection AF and two silent advance modes. Optional WIFI transmitter with GPS capability. And lens Vignetting Correction
Cons - AF system inherited from original 5D is showing its age. JPEG processing offers les detailed results than RAW. at highest ISO horizontal banding noise is visible in dark areas. Mirror lockup is buried in custom functions. and 3.9 fps frame rate is slowest in this class. No APS-C format crop mode.Limite AF and exposure control on video mode
DID YOU KNOW
"MINOLTA"
Formed in 1928 under the name of the Japan-Germany Camera Company by Kazuo Tashima, the name was changed to Molta in 1931 from the German tiltle Mechanismus Optik und Linsen von Tashima. The company name was changed to Minolta in 1962 from the full name of Mechanical INstruments and OpticaL by TAshima.
"FUJI"
The name of Fuji is simply taken from the name of the highest mountain in Japan, Mount Fuji.
"LEICA"
Ernst Leitz started making lenses for microscopes and telescopes in 1849, and it wasn't until 1911 when Oskar Barnack joined the Leitz firm that it made its first camera. It was going to be called LECA, until someone suggested that LEICA (LEItz CAmera) sounded better. The name stuck.
"KONICA"
The firm of Konishiroku Kogaku have been involved in making photographic and lithographic materials for over 200 years. It adopted the name Konica when it started making cameras in the 1940's.
"MAMIYA"
The name was simply taken from the surname of the inventor and designer of the camera, Seiichi Mamiya.
"NIKON"
The original name for Nikon was Nippon Kogaku, meaning "Japanese Optical". The company was formed in 1917 and its name was changed to Nikon in 1946 by taking the "Ni" from Nippon and the "Ko" from Kogaku and adding an "n".
"CANON"
The original name for CANON cameras was "Kwanon", the Buddhist god of mercy. The first Kwanon camera was built in a small Tokyo workshop in 1934. The name was changed to CANON in 1935 to avoid offending religious groups
...that the former USSR was the world's largest producer of cameras? They produced more cameras than any other country in the world. The first models of the Soviet Leica FED and Zorki clones were made in more numbers than all Leica cameras ever produced. The total number of Leica-inspired Soviet cameras numbered in the millions. The Soviets tried to improve on the original- and they did succeed in many ways.
...that the first 35mm SLR was made in the Soviet Union? The GOMZ (later to become "LOMO", the maker of the cult LOMO LKA camera) produced the "Sport" ("Спорт") in 1935, a year before the German Kine-Exakta was released.
...that the Kiev rangefinder camera was probably the camera whose design had the longest production run? The camera was based on the mid 1930s Contax II and III. The Soviets captured the Contax works after WWII and shipped its tools and machines as war reparation to the Ukrainian "Arsenal" camera factory where production continued under the "Kiev" badge. The camera hardly departed from the original 1935/36 German design. The Kiev was discontinued in the middle or late 1980s. That's an almost 60-year production run.
...that the so-called "Pentax screw mount"- aka M42 screw mount- should be, and more accurately, called as "Contax Screw Mount"? Contax developed this lens mount and introduced it in their "Contax-S" camera in 1949. It was the first pentaprism 35mm SLR. This Contax SLR was the basis of all 35mm SLRs which followed it- Nikon, Canon, Pentax and everyone else included. Because of political/economic issues, this Contax (made in East Germany) had to be renamed Pentacon (PENTAprism CONtax) to avoid run-ins with West German Carl Zeiss who legally owned the Contax name outside the Eastern Bloc.
Formed in 1928 under the name of the Japan-Germany Camera Company by Kazuo Tashima, the name was changed to Molta in 1931 from the German tiltle Mechanismus Optik und Linsen von Tashima. The company name was changed to Minolta in 1962 from the full name of Mechanical INstruments and OpticaL by TAshima.
"FUJI"
The name of Fuji is simply taken from the name of the highest mountain in Japan, Mount Fuji.
"LEICA"
Ernst Leitz started making lenses for microscopes and telescopes in 1849, and it wasn't until 1911 when Oskar Barnack joined the Leitz firm that it made its first camera. It was going to be called LECA, until someone suggested that LEICA (LEItz CAmera) sounded better. The name stuck.
"KONICA"
The firm of Konishiroku Kogaku have been involved in making photographic and lithographic materials for over 200 years. It adopted the name Konica when it started making cameras in the 1940's.
"MAMIYA"
The name was simply taken from the surname of the inventor and designer of the camera, Seiichi Mamiya.
"NIKON"
The original name for Nikon was Nippon Kogaku, meaning "Japanese Optical". The company was formed in 1917 and its name was changed to Nikon in 1946 by taking the "Ni" from Nippon and the "Ko" from Kogaku and adding an "n".
"CANON"
The original name for CANON cameras was "Kwanon", the Buddhist god of mercy. The first Kwanon camera was built in a small Tokyo workshop in 1934. The name was changed to CANON in 1935 to avoid offending religious groups
...that the former USSR was the world's largest producer of cameras? They produced more cameras than any other country in the world. The first models of the Soviet Leica FED and Zorki clones were made in more numbers than all Leica cameras ever produced. The total number of Leica-inspired Soviet cameras numbered in the millions. The Soviets tried to improve on the original- and they did succeed in many ways.
...that the first 35mm SLR was made in the Soviet Union? The GOMZ (later to become "LOMO", the maker of the cult LOMO LKA camera) produced the "Sport" ("Спорт") in 1935, a year before the German Kine-Exakta was released.
...that the Kiev rangefinder camera was probably the camera whose design had the longest production run? The camera was based on the mid 1930s Contax II and III. The Soviets captured the Contax works after WWII and shipped its tools and machines as war reparation to the Ukrainian "Arsenal" camera factory where production continued under the "Kiev" badge. The camera hardly departed from the original 1935/36 German design. The Kiev was discontinued in the middle or late 1980s. That's an almost 60-year production run.
...that the so-called "Pentax screw mount"- aka M42 screw mount- should be, and more accurately, called as "Contax Screw Mount"? Contax developed this lens mount and introduced it in their "Contax-S" camera in 1949. It was the first pentaprism 35mm SLR. This Contax SLR was the basis of all 35mm SLRs which followed it- Nikon, Canon, Pentax and everyone else included. Because of political/economic issues, this Contax (made in East Germany) had to be renamed Pentacon (PENTAprism CONtax) to avoid run-ins with West German Carl Zeiss who legally owned the Contax name outside the Eastern Bloc.
Leica M9
Leica has officially revealed the M9 - a full frame version of its M-mount rangefinder. The Leica M9, with its 24 x 36mm, 18 megapixel sensor is, according to the company: 'the world's smallest full-frame system camera.' The body is available in a new 'Steel Gray' finish and offers minor button re-arrangement over the M8 - all the major changes relate to the internals. The Kodak-developed CCD sensor features improved offset microlenses to optimize performance at the edges of the frame along with a sensor cover with improved filtering of infrared light so lens-mounted IR filters are no longer needed. Most importantly, the 35mm film-sized sensor means every Leica M-mount lens provides the originally intended field of view.
Tuesday, September 8, 2009
Sigma 70-300mm F4-5.6 DG OS
Focal length 70-300mm
Diagonal Angle of view 34.3º - 8.2º
Maximum aperture F4 - F5.6
Minimum aperture F22
Lens Construction
16 elements/11 groups
Number of diaphragm blades 9
Minimum focus 150 cm
Maximum Magnification Ratio
1:3.9
Image stabilization • Yes
Filter thread • 62mm
Supplied accessories • Front and rear caps
• Bayonet-type Lens Hood
• Soft Case
Weight 610g (21.5 oz)
Dimensions 76.5mm diameter x 126.5mm length
(3.0 x 5.0 inches)
Lens Mount Sigma AF, Nikon AF, Canon AF, Pentax AF, Sony AF
Photoworld Asia 2010 in Manila
Where:
Trade Show: Jan 28 – Feb 3, 2010 at the Glorietta, Ayala Center Makati
Convention: Jan 29 – Feb 1, 2010 at the Asian Institute of Management, Makati
Speakers
Kevin Ames,
Manny Librodo,
Jose Librodo,
Hugo D. Yonzon III
Jason Magbanua,
John Tronco, Isa Lorenzo
Bernie Ledesma
Monday, September 7, 2009
Tips on Improving DSLR skill 2
Tips on improving DSLR skill on Landscapes
1. Try shooting low and generally follow the rule of thirds.- based on what you see, you have to choose either to give more weight to either the foreground on the sky, and that determines where you place the horizon.
2.Always clean your gear before shoot to avoid having clean them on location. -You not only might miss a shot while you're cleaning, but it is also safe to clean your camera indoors. and you'll just hate yourself if you come home with a beautiful sunset shot only to find sensor dust specks on the clouds
3.Make sure you've got all the necessary equipment packed, especially your tripod and filters- You need tripod for long exposures, and filters make it easier to take long exposures and balance exposures between sky and foreground
4.Always change lens with body facing down and away from wind- minimize the dust and sand getting onto your sensor
5. Anticipate the moment, dont just react to the great light- Dont panic when the sky is showing its best colors, scout the location get a feel for what makes it special and decisive about what you want to shoot. you dont want to waste the magic window when light is perfect
6.Make sure filters lie flat across the lens when you shoot -otherwise you get light leaks that will show up into the picture
7.Get a compass and learn how to use it
8.Have Patience- obeserve sunrise and sunsets so you'll be familiar with how the colors
change during the transition when you know that and you're patient enough to wait for them you can capture the best colors in the sky for you're landscape
9.Make sure to use lowest iso 10. Most important thing of all shoot and have fun!
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