Wednesday, March 25, 2009

Tamron 28-75mm F/2.8 review


f/Stop Range : 2.8-32
Minimum Focus Distance : 13″ (33 cm), over entire zoom range
Magnification : 1:3.9
Zoom/Focus Control : Two-touch
Angle of View : 75 to 32 Degrees
Groups/Elements : 14/16
Length : 3.6″ (92mm)
Maximum Diameter : 2.9″ (73mm)
Filter Size : 67mm
Weight : 1.50 lb (510 g)

With an equivalent zoom range (on my Canon 40D) of 44.8mm to 120mm and constant aperture at F/2.8, the lens serves a dual purpose as a portrait and walk-around lens.

It is light weight compared to the Canon L 24-70, very sharp, has good contrast and on my camera the focus is fast and accurate. As far as focus is concerned, do not use “AI Servo” unless you are shooting subjects moving at high speed (the lens will “hunt” for focus, even if it is not necessary). On “One shot AF” and “AI Focus AF” the lens is very accurate.

As far as distortions, vignetting and chromatic aberrations, I didn’t have any problems using this lens in real life situations. The lens is also well build, with a metal mount and a “lock” button to prevent “zoom creep”.

One common problem that I’ve heard about the Tamron 28-75mm is the front / back focus. I’ve tested my lens and I’ve found out that front focus (just slightly) only occurs at 28mm, but I’m very happy with the situation. I can get a better bokeh behind the subject when using it for portraits. In a very strange way, I’ve turned the lens “problem” into a photographic advantage. Basically, I know what the strong and weak points of my lens are and use it accordingly.

Here are the test images:

How I’ve tested the lens: test chart on the table (not a very flat surface, but it worked), 1 off camera flash (430 EX + off-camera Shoe Cord) and camera on a tripod, pointed down at 45 degrees. More info and the test chart can be found at this location: http://www.focustestchart.com/chart.html

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Tuesday, March 24, 2009

Dermaga Pulau Pramuka




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Friday, March 20, 2009

Taking Panoramic Landscapes

I love panoramas. There's something very appealing about their shape. It's probably because we see the world more in these dimensions than the near square format of standard film/sensor frames. It might also explain the upsurge in the popularity of widescreen TVs!

Panoramas have a reputation of being hard to take. There are dedicated panorama cameras available but unless you've got at least a thousand dollars to spare, you probably can't afford one! But you can take panoramas with any kind of camera.

All a panorama is, is a sequence of images where you turn slightly for each different frame. In the old days, before PCs and the likes of Photoshop were around, you'd take your prints (there wasn't much point in shooting panoramas on slide film, for obvious reasons), lay them out on a table and position them over each other where they overlapped. A bit of sticky tape held them together. [As a side note, this technique was used by NASA to build up mosaic pictures of the planets and satellites their spaceprobes visited, up till the late '70s/early 80s when computers were introduced to make the process less laborious].

Now that PCs and image manipulation packages are easy to come by, high-quality panoramas can now be created by anyone. If you're shooting slide or negative film, you will need to have your images scanned before you do anything else.

DIY Panoramas

The idea behind taking panoramas with SLR cameras is that the camera is rotated around its nodal point during each successive exposure. What's the Nodal Point? It's the point inside your camera where the light rays converge and flip over. It's different for different focal lengths (on zoom lenses) and for different prime lenses (fixed focal length lenses like a standard 50mm lens). It's important to rotate about this point to eliminate image mismatches due to changes in parallax. Parallax is the apparent shift of an object against a background due to a change in observer position.

Just to be clear, the Nodal Point is not the same as the film/sensor plane. Generally, for most SLR cameras and lenses, the Nodal Point is located somewhere towards the center of the lens barrel and lies in front of the image/sensor plane.

The Problem With Parallax

Parallax is easily demonstrated by a simple experiment. Hold up your finger about 1 foot in front of your face and alternately open and close your left and right eyes. You'll notice that your finger shifts left and right with respect to the background depending on which eye is open. Try another experiment: With your finger still raised, close one eye and turn your head from side to side. Notice how your finger moves with respect to the background. This relative movement is due to the fact that you're not rotating your head around your eye's nodal point, which is somewhere in the center of your eyeball. Instead, you're rotating about your spine which is several inches to the rear and off to one side. It is this relative side-to-side motion that we try to eliminate when setting up a camera for panoramas.

Now, if you consider a camera held up to your face - it will suffer even greater parallax errors as it's farther from your spine (the point of rotation of your head) than your eye. It's surprisingly common for people to take panoramas in this fashion and then find the individual pictures don't match up.

So use a tripod and rotate the camera on the tripod. The parallax errors will be significantly smaller but there will still be some error involved. However, the images will match up better than with the head rotation method.

Mechanical Contraptions

What perfectionists strive for is to have the camera rotate about the nodal point. There are brackets and contraptions available that will let you offset your camera from the tripod's axis of rotation and with a little experimentation and trial and error, you can position your camera so that its nodal point is directly over the axis of rotation of the bracket. Getting this spot-on means your images should line up perfectly.

A few months ago I bought such a bracket - the Kaidan Kiwi. This comes in two halves which produce an L-shaped bracket. Its instruction manual explains how to set it up and find the nodal point for your camera and lens. However, you have to get your tripod perfectly level before using it, otherwise you end up with a curved panorama rather than a straight one.
I've had good success using this bracket, but it is large and heavy and certainly a bit too cumbersome to be carrying on long walks or while away on vacation.

AutoStitch To The Rescue
Then I recently came across a free bit of software called AutoStitch. Written by a couple of students at the University of Columbia, this takes all of the heartache out of creating panoramas. All you do is select the size of the final image and tell it what images you want it to stitch. It then goes off and produces your panorama.

It really is that simple. Unless successive images are radically different in exposure (i.e. one image to too light or dark compared to another), it seamlessly blends them. It performs all the warping of the images necessary to get them to align (other software I've used can cause ghosting in the overlap areas where it hasn't quite aligned the images). It also aligns multiple rows of images rather than just a single strip.

Even better, it doesn't require you to set up your camera to rotate about its nodal point. When I was in Crete last year, I tried shooting a few panoramas with my Canon EOS 300D held up to my eye (I didn't have a tripod with me). When I got home, I tried stitching the pictures together using various bits of software (including software dedicated to stitching images together) and didn't get satisfactory results. I knew, though, that it was because I'd swivelled the camera about my spine. But I tried these images with AutoStitch and they came out perfectly.

I went walking up the Wicklow mountains in Ireland no too long ago and up to a high point called Djouce which offers a view over the rolling hills south of Dublin. As an experiment, I shot 8 frames while rotating my head about the scene (camera to eye as per normal). I wanted to see if the Crete photos were a fluke as the panoramas from there were composed of, at most, 3 frames each (sometimes 2).

Conclusion

What can I say? I plugged 8 frames into AutoStitch and after a bit of time processing the images, it produced a perfect panorama with no ghosting I could see in the overlap reasons. I like software like that. It may only do one thing but it does that one thing very well.
Give AutoStitch a try. It's free and, so far, it produces the best panoramic results of all the panorama/stitching software I've tried.

One thing to remember when taking panoramas is that the exposures of each frame should be the same. So if you make your first exposure at f/8 and 1/125 of a second, take them all using those settings. Yes, you will have to put your camera into manual mode. Otherwise, you run the risk of having radically different exposures for your images. For example, if you're panning over a landscape that contains water, like a lake, any sunlight reflected off the water may make your camera take a shorter exposure than for the other frames in your sequence. Setting your camera to manual mode will prevent that.

About the Author
Gary Nugent is a software engineer by profession and has been in the business for over 20 years. Photography has been a hobby for an even longer period of time and he's now even more passionate about it since making the switch to using a digital SLR camera. You'll find more tips and techniques at Great Landscape Photography: http://www.great-landscape-photography.com


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Tuesday, March 17, 2009

Macro Photography

The photos that can be included in this category are those that depict reality at a 1:1 scale. So, if you take the picture of a butterfly and it has a wing span of 3 cm, the printed image must have a butterfly with a wing span of at least 3 cm.

For DSLR cameras, there are specialized very expensive macro lenses, witch provide extreme magnification and image detail. However, most digital cameras have a zoom lens, with built in macro capabilities.

What you must understand about macro photography is the fact it can be very satisfying. The amount of detail that can be captured with even a modest, low cost digital camera is breathtaking. In dealing with macro photography, you need patience and luck.

First, you need patience in setting the camera; because you have a very shallow depth of field, the camera must be very still, or the image will be out of focus. Luck is required when dealing with subjects like insects. They tend to move...

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Thursday, March 12, 2009

Canon 450D EOS Digital Rebel XSi Specifications

The Canon EOS 450D / Digital Rebel XSi has been announced at January 2008.The info provided here has become a comparison between what I’ve supposed the specifications will be and the actual product.

Considering the latest product releases from Canon, the Canon PowerShot G9, Canon EOS-1Ds Mark III and Canon EOS 40D it seems that the successor of the 400D Digital Rebel XTi will have a price about 900-1000 USD

Here is the specifications:
  • Max resolution: 4000 x 3000 (4272 x 2848 pixels, 3/2 aspect ratio instead of a 4/3)
  • Effective pixels: 12 megapixels
  • Sensor size: 22.2 x 14.8 mm
  • Sensor type: CMOS
  • ISO rating: 100 - 1600
  • Auto Focus: Yes
  • Manual Focus: Yes
  • Auto focus type: Multi-BASIS TTL, 9 focus points (diamond shape) (9-point CMOS sensor, cross-type F2.8 at center)
  • White balance override: 8 positions & manual preset (7 positions and manual preset)
  • Min shutter: 30 sec + Bulb
  • Max shutter: 1/4000 sec
  • Built-in Flash: Yes
  • External flash: Yes, hot-shoe & sync
  • Flash modes: External
  • Exposure compensation: -2 to +2 EV in 1/3 EV or 1/2 EV steps (-3 to +3 EV in 1/3 EV or 1/2 EV steps)
  • Metering: TTL 35-zone SPC, center weighted, partial, spot
  • Aperture priority: Yes
  • Shutter priority: Yes
  • Focal length multiplier: 1.6
  • Lens thread: Canon EOS EF, EF-S mount
  • Continuous Drive: Yes, 3 fps max 60 JPEG, 17 RAW (3.5 fps up to 53 JPEG / 6 RAW frames)
  • Movie Clips: YES
  • Self-timer: 10 sec or 2sec
  • Storage types: Compact Flash (Type I or II) (SD / SDHC card)
  • Uncompressed format: RAW
  • Compressed format: JPEG (EXIF 2.2)
  • Quality Levels: Fine, Normal
  • Viewfinder: TTL
  • LCD: 3″ with Live View
  • Video out: Yes
  • USB: Yes, 2.0
If you’ll check the whole list of improvements from the 400d to 450d you’ll be really impressed. There are only two things that might cause a problem (from my point of view):

The 450d has almost the same physical dimensions as the 400d, for my hands, it’s too small.

Image quality at 12 megapixels, a cropped sensor and the current lenses. It seems that if somebody would like to get the best out of this camera would be to buy very expensive Canon L series lenses. I really don’t think that the standard kit lens has enough resolution to cover this sensor (remember, the kit lens was first introduced on Canon 300D – only a 6 megapixels sensor)

However, overall, this is a very impressive camera. Considering the 14bit capability and the possible usage of L series lenses, this camera could provide the same image quality as a Canon 5D at only half the price!

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Monday, March 9, 2009

KODAK Z980 Digital Camera


At January 2009 Eastman Kodak Company (NYSE:EK) announced new additions to its digital camera line, led by the high-zoom KODAK Z980 Digital Camera, featuring outstanding control and Kodak’s innovative Smart Capture feature that consistently delivers high quality images.

Featuring a wealth of power and versatility, the KODAK Z980 Digital Camera offers a 26 mm wide angle, professional quality, 24X image stabilized optical zoom lens, a vertical shutter release and a hot shoe, all at an affordable price.

The Z980 enables serious photographers to easily handle both long-distance and wide-angle shots, and boasts Kodak’s innovative Smart Capture feature, which automatically adjusts the camera’s settings to deliver brilliant images automatically.

“The Z980 is an ideal camera for photographers looking to do more and get more from their digital camera,” said John Blake, General Manager Digital Capture and Devices, Vice President, Eastman Kodak Company. “The versatile lens, combined with our exclusive Smart Capture feature, lets consumers shoot great pictures in any setting — from daylight to night or from close-ups to landscapes, the camera makes adjustments automatically.”

The new KODAK Z980 Digital Camera offers:

  • Kodak’s exclusive Smart Capture feature, which analyzes scenes and adjusts camera settings to deliver beautiful pictures more often;
  • 26 mm wide angle/24X SCHNEIDER-KREUZNACH VARIOGON Image Stabilized Optical Zoom Lens;
  • HD picture and video capture;
  • Vertical shutter release and detachable vertical grip, for greater comfort and control when shooting scenes vertically;
  • Hot shoe for the optional KODAK P20 flash;
  • 12 MP for prints up to 30″x40″;
  • Bright and detail-rich 3-inch indoor/outdoor color display;
  • Compatible with new KODAK WI-FI Memory Cards and KODAK SDHC/SD Memory Cards;
  • Available at US$399.95 MSRP from Spring, 2009.
Kodak also introduced new models to its M-Series Digital Camera line, led by the KODAK EASYSHARE M380 Digital Camera. A sleek but powerful digital camera for style-savvy consumers, the M380 delivers an innovative feature package led by Kodak’s Smart Capture feature, and also boasts a 10MP sensor, 5x optical zoom, and 2.7″ LCD. The M380 will be available in black, red and teal, and retail at US$179 MSRP from March, 2009;

Also new to the KODAK M Series Digital Cameras are:
  • KODAK EASYSHARE M340 Digital Camera, offering Smart Capture, 10MP sensor, 3x optical zoom, 2.7″ LCD, in a slim body design; available in blue, blue-green, silver, and red, and retailing at US$149 MSRP from March, 2009;
  • KODAK EASYSHARE M320 Digital Camera, featuring Kodak Perfect Touch technology providing automatic red-eye reduction, shadow lightening and more, 9MP sensor, 3x optical zoom, 2.7″ LCD; available in black, silver, red and blue, and retailing at US$129 MSRP from February, 2009.
Accessories

A range of accessories will be available for the new KODAK Digital Cameras including KODAK Li-Ion Rechargeable Digital Camera Batteries and battery charger kits; KODAK SD and SDHC High Performance Memory Cards; KODAK Camera Bags and much more.

About Kodak

As the world’s foremost imaging innovator, Kodak helps consumers, businesses, and creative professionals unleash the power of pictures and printing to enrich their lives.

To learn more, visit the newly redesigned http://www.kodak.com and follow our blogs and more at http://www.kodak.com/go/followus.

More than 70 million people worldwide manage, share and create photo gifts online at KODAK Gallery –join for free today at www.kodakgallery.com


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Sunday, March 1, 2009

Terms beginning with "B" in Photography

B (Bulb) - A shutter speed dial setting that indicates that the shutter will remain open as long as the release button is depressed - also known as the “B setting ” or "Bulb" setting. The "B" setting is used for time exposures.

B&W - Black and white. Also appears as "B and W" and "B/W."

BACK - The removable part of a medium or large-format camera that holds the film or the digital recording surface. "Backs" are attached to the back of the camera, hence their name. They shield the film from light except when exposed in the camera.

BACKGROUND - The part of a scene that appears to be furthest from the viewer, behind objects in the foreground.

BACK PROJECTION - Projection, usually of a transparency, onto the rear of a translucent screen.

BACKDROP - The background in a studio.

BACKGROUND - The area within the viewfinder that is behind the subject of a photograph.

BACK-LIGHTING - Light directed at the subject from behind the subject.

BACKSCATTER - Suspended particles in water that are illuminated, and therefore captured on film as a cloud or scattering of light dots, when using a flash underwater near the lens.

BACK-UP - A safety measure that is a copy of an image, a file, a folder or an entire computer drive to be restored in the event that the original becomes lost.

BALANCE - Compositional harmony of a scene based on the placement of elements of different sizes, shapes and colors.

BARE BULB - Electronic flash unit used without a reflector or diffuser.

BARN DOORS - These are small “gobos” (light-blocking devices) that fall under the general category of “grip equipment.” They are accessories that attach to studio lights and swivel on hinges (just like the doors on a barn) to allow the photographer to control the light’s direction and the width of the light beam.

BARREL DISTORTION - Image distortion caused by a lens, where the edge bows outwards like a fisheye or wide-angle lens's image.

BATCH NUMBERS - Series of numbers imprinted by the manufacturer on the packaging of film and light-sensitive products to indicate that the materials are all from the same production batch, and therefore share closely-similar qualities, such as film speed and contrast.

BELLOWS - A folding sleeve-like device usually made of fabric that fits between the lens and the camera that allows for extended separation of lens and film plane. A bellows is used in close-up photography, and performs a function similar to that of extension tubes, except that the tubes are fixed and the bellows is minutely adjustable.

BETWEEN-THE-LENS SHUTTER - A shutter situated between two lens elements.

BITMAP - A bitmap is a picture that is an arrangement of tiny squares of different colors, called pixels. For the file extension, ".bmp," see .BMP below.

BLEED - Describes a photographic print that extends to the edges of the paper (beyond the trim marks on a page) and has no visible border or defined margin area.

BLOW-UP - As a noun, blow-up (or blowup) is another term for an enlargement of a photographic print. As a verb, it is the actual enlarging of the image, as in “Please blow up this negative to an 11" X 14" print.”

BLUR - Denotes a photograph in which movement, either camera movement, zoom lens movement or movement within the scene (e.g. a subject in motion), is recorded at a slower shutter speed than is necessary to “freeze” the motion as a sharp image. Blur is often intentionally created by a photographer who wishes to convey a sense of motion.

.BMP - (Bitmap) The extension for an uncompressed image file format created by Microsoft that is mainly used in Windows-based applications.

BOOT TIME - The time it takes for a digital camera to be ready to take pictures after turning it on.

BOUNCE FLASH - Flash illumination of a subject by reflection off a surface (such as a ceiling or wall) as opposed to direct flash, which is flash light aimed straight at the subject. (Sometimes also called "Bounce lighting.")

BOX CAMERA - Simple camera with a fixed, single-element lens and a light-tight box to hold the film. The shutter and aperture are usually pre-determined and unalterable (typically 1/25 sec at ƒ11.) Early consumer cameras developed by George Eastman were box cameras (e.g. the “Brownie” camera) . They could not be focused, per se. The lens was set to a hyperfocal distance that gave acceptably-sharp pictures if the subject was a given distance from the camera and correct exposure depended upon bright sun illuminating the scene.

BRACKET or BRACKETING - Refers to taking a series of pictures, at least three, of the same subject with varying exposures - (1) the main exposure, which is presumed to be correct, but may not be; (2) an overexposure, generally of or 1 stop’s difference from the main exposure, and (3) an underexposure of , 1 or 2 stop’s difference from the main exposure. The theory behind exposure bracketing is that the photographer may not be certain that the main exposure is best for the subject matter, and the subsequent exposures will provide “insurance” that at least one of the images will provide acceptable exposure. Sometimes, though, the photographer may simply want to see the effects of different exposures of a scene. The term “bracket” is analogous with grammatical brackets or parentheses, where they are located on either end of a phrase. “Bracketed” exposures fall on either side of the exposure that is presumed to be correct.

BROAD LIGHTING - Broad lighting occurs when the main light illuminates the side of the subject's face that is turned toward the camera. The BROWNIE is the original consumer camera, developed by George Eastman in 1888.

BROWNIE - Brand name of Kodak’s first consumer box cameras.

B.S. - B.S. refers to the British Standard for film speed measurement. BSI refers to the British Standards Institute which determined the B.S. system. It employed the same film speed numbering system as the American Standards Association- ASA. Both are now defunct, having been replaced by ISO for rating of the sensitivity of film and photographic materials.

BUBBLE JET - Canon's name for its inkjet printing system.

BUILT-IN LIGHT METER - A reflective exposure meter that is a built-in component of a camera.

BULK FILM - Film produced in very long, uncut strips - rolls that are too long to fit into cameras not equipped with a bulk camera back accessory. Many photographers buy their film in bulk, then load the bulk film into a “bulk film loader” which permits them to cut the bulk film into however many frames they wish, and to load the smaller strips into film cartridges that permit film reloading. It is an economical way to purchase film.

BURNING or Burning-in - Also known as "Printing in." In a darkroom, providing extra exposure to an area of the print to make it darker, while blocking light from the rest of the print.

BUTTERFLY LIGHTING - In a studio, the main light is placed fairly high, directly in front of the face - aimed at the center of the nose. It casts a shadow shaped like a butterfly beneath the nose.

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