Image Pixel and Photo Print

greenspun.com : LUSENET : Photography Singapore : One Thread

For those who are interested in sending their digital image for photo print, I got below info from

[url]http://www.kodakexpress.com.sg[/url] and [url]http://www.megapixel.net/html/issueindex.html[/url]

PRINT SIZE------- 3R(3"x5")-- 4R(4"x6")---5R(5"x7") MIN. RES (pixels) 640x480--- 1024x768--1280x1024 PRINT SIZE------- 6R(6"x8")----8R (8"x10")--- S8R (8"x12") MIN. RES (pixels) 1600x1200--1800x1200---1800x1200

PRINT SIZE------- 10R (10"x12")---S10R (10"x15") MIN. RES (pixels) 1800x1200------1800x1200

(the --- lines are there to help me ctrl the spacing)

If I perform the calculation: 640 x 480 = 307 200 pixel 1024 x 768 = 786 432 pixel 1280 x 1024 = 1 310 720 pixel = 1.3 megapixel 1600 x 1200 = 1 920 000 pixel = 2.1 megapixel 1800 x 1200 = 2.3 megapixel 2048 x 1536 = 3 megapixel 2400 x 1600 = 4 megapixel

If I am sending my photo for 4R print, my image size has to be at least 1024 x 768 pixels. A 1.3 megapixel Digicam is sufficient. From the calculation above, a 2.3 megapixel camera will allow me to print a 10" by 15" photo at any Kodak outlet.

So, what’s the use of a higher megapixel camera? It will capture image at higher pixel size and give more details but it will take up more memory space. For eg: If I capture an image at 2048 x 1536 and another at 640 x 480. Then extract a 640 x 480 from 2048 x 1536 image and compare it to the one taken at 640 x 480, I would see more details but the extracted image would be a cropped one. To see more information and pictures about this, you can go to:

[url]http://www.megapixel.net/html/issueindex.html[/url] (Go to->Articles ->Common types of resolutions) According to the information from the above web site:

“Generally, most digital cameras have little problems yielding a sharp and well-defined image with subjects 1 to 5 meters away (3 to 15 feet).

Distant landscapes, which by their very nature, tend to contain a large amount of small detail, will generally turn out "sharper" and clearer with cameras that use 2 megapixel, and above, CCDs.

1.3 and 1.5 million pixel cameras, will produce acceptably detailed images with subjects 30 metres (90 to 100 feet) away. After that, their photos tend to become a bit more impressionistic.

The rule of thumb is simple: the greater the complexity of the subject, the greater the number of pixels required”

Hope the above info is helpful to you. Regards, Arthur

-- Arthur (xuruilong@yahoo.com.sg), December 18, 2002


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