Understanding Photo Paper Weight (GSM)
GSM (Grams per Square Meter) is a measure used to find out the weight of paper in square meters. The higher the GSM number, the thicker and heavier the paper. To measure GSM, we weigh a piece of paper that measures 1 meter x 1 meter. For example, if the paper weighs 200 GSM, it means that 1 square meter of paper weighs 200 grams. This GSM value is important for assessing the thickness and strength of the paper.
GSM (grams per square meter) is the standard measure of paper weight. A higher GSM number indicates a thicker, stronger paper. Paper with low GSM is typically thinner and plier, while paper with high GSM is more durable, especially for high-quality prints.
The weight of the paper affects the way the ink absorbs and holds on the surface. Paper with high GSM often has a special coating that better preserves color details and prevents wrinkles due to ink moisture. In addition, the heavier the paper, the more durable the print will be and the more suitable for long-term storage.
Paper Weight Recommendations Based on Intended Use
Here is a guide to choosing the weight of paper according to your printing needs:
Below 150 GSM
Ideal for printing photos in bulk or photos that will be sent by airmail. This paper is lightweight and flexible, but it is less suitable for long-term printing.
150-250 GSM
Standard for good quality photo printing. The paper in this range is thick enough to display sharp colors without warping easily, so it is often used for photo albums and everyday prints.
Above 250 GSM
It is recommended for high-quality photos to be framed. The paper is thicker and stronger, providing a more professional look and long-term resistance to moisture and environmental changes.
Common Photo Paper Sizes and Aspect Ratios
Choosing the right size of photo paper is essential for the print to match the composition of the image. Each paper size has a different aspect ratio, which can affect how the photo is printed, whether it needs to be cropped or there will be a white border around it.
Frequently Used Photo Paper Sizes
Some common standard sizes for printing photos are:
- 6 x 4 inches (15 x 10 cm): Classic size for printing snapshots from 35mm film or standard photos from DSLR cameras.
- A4 (21 x 29.7 cm): Often used for printing large photos, portfolios, or collections that you want to frame.
There are also 5 x 7 inches (13 x 18 cm) and 8 x 10 inches (20 x 25 cm) sizes that are commonly used for larger prints.
Understanding the Aspect Ratio and Its Effect on Print Results
The aspect ratio is the comparison between the width and height of an image. If the aspect ratio of the photo does not match the size of the paper, then the image must be cropped or there will be a white border around the photo. Here are some common aspect ratios:
- 3:2 ratio: Standard on DSLR and 35mm film cameras. This ratio is suitable for 6 x 4 inch photo paper, resulting in prints without cutting.
- 4:3 ratio: Common on compact cameras and smartphones. If printed on 6 x 4 inch paper, the photo should be cropped at the top and bottom, or left with a border on the side.
- 16:9 ratio: Used for panoramic or widescreen photos. If printed at a standard size, it will usually leave a large border on the top and bottom unless it is cut to the print size.