Enlarging a picture involves changing the original dimensions and resolution to align with specific requirements. Sometimes the change is so drastic that the image itself becomes blurred or fuzzy, resulting in loss of resolution and quality. Depending on where you intend to use the picture, this may not be the option you want to consider. However, if you have a picture of an already small object or took one from a device that only produces small images, the only route to consider is enlarging. Additionally, if you intend to use the picture on a larger surface you may also need to enlarge. In the world of photography, when photographers refer to enlarging they also use the terms up-scaling and up-sizing. They know that different factors must be taken into account such as what the course The Fundamentals of Photography covers before augmenting a picture.
Before we look at some of the tools that you can use to enlarge a picture, we will first examine what actually defines the quality of a picture.
Pixel per inch abbreviated ppi is the measurement used to determine the pixel density of a picture. The pixel density is associated with the resolution and quality of the picture. When you enlarge a picture you increase or separate the pixels. This causes less pixels per inch and the program you use will try to compensate for the loss in pixels. This is a scenario you want to avoid because the output is usually not sharp and becomes blurred compared to the original picture. The print size of the picture is directly linked to the ppi so if you intend to print, the number of pixels that are present in every inch will determine what your print quality will be. There is no direct rule as to what the correct ppi should be as this depends on the picture itself and the intended use. The generally accepted standard, however, is 300ppi. When it comes to ppi, sampling and not sampling are the two ways you can use to change the print size. Not sampling is the preferred option because it does not affect the pixel count per inch.
Dots per inch or dpi is often used interchangeably with ppi, but the two are distinct and should not be confused. If you decided to reduce the dpi then you are reducing the number of colored dots per inch. When you select to print your picture, your printer will usually give you the option to modify the ppi and dpi per inch to get a bigger picture. Finding the best ratio between the two will determine the quality.
Numerous file formats for pictures currently exist and knowing which to select can be confusing. The most popular types are JPG, GIF, RAW, TIFF, PNP and BMP. RAW and TIF picture file formats are usually used for high resolution images. They use lossless compression so the quality of the image is good compared to other formats even when enlarged. Image quality will always be lost if you choose to enlarge a pictures that are in the format of JPG, BMP and PNP. GIF is never a good option when saving pictures because this file format uses only 256 colors from a pool of over 16 million. By considering the file format, you can assess the options available and also the likely output results when you choose to enlarge.
The sharpness of the picture, lighting quality, focus and distance are other factors to take into consideration when enlarging a picture. If the image already appears blurred due to lack of focus, enlarging will only make the defect more pronounced. The same is true for pictures that are taken at close ranges and those that lack proper lighting. If you are using a macro lens, the course Mastering Macro Photography is a useful guide to apply when taking pictures of small objects and doing close-ups.
Image Editing Tools
Now that we have looked at some of the factors to take into consideration before enlarging a picture, the next step is to look at some of the tools that are available on the market.
- Photoshop CS
Developed by Adobe Systems, Photoshop CS features a list of different options that make it easy to enlarge a picture with jut a few clicks of the mouse. Once the image is opened in the software, you select “Image” → “Image Size”. The last option will present an on-screen dialog box where you will see the option to adjust the resolution and image size by changing the height and width. You can set the resolution field to 300 ppi. It is always important to select the “Bicubic Smoother” option if you decide to re-sample the picture. This command will ensure that image quality is preserved when enlarged. For more advanced changes you can use the tips in the course Photoshop for Artists to get more ideas.
Microsoft Word and Microsoft Office Picture Manager are readily available if you are using Microsoft Office. To use Microsoft Office Picture Manager simply open the picture you wish to edit and then select “Edit Pictures” which is located at the top of the program. Different options will appear in a right bar menu, but the one you need to pay attention to is “Resize”. This option will then allow you to enter the preferred settings you want by adjusting the height and pixels of the picture. You can watch how the picture changes as you make different adjustments until you are satisfied with the output.
Pictures that are saved in a Word document can be altered using the “Picture Tools” menu bar that appears once the picture is selected. The option to enter the width and length of the picture you selected will appear at the top right corner of “Size” group in the “Format” tab. Simply adjust and observe how the resolution changes until you are satisfied with the results.
If you are using a Windows operating system, the Paint program can be used to enlarge a picture by simply clicking the “Resize” option and then adjusting the percentage and pixels quantity that are represented on the X and Y axis (horizontal and vertical).
It goes without saying that a picture says a thousand words, but many times meaning is lost because of poor quality. The blog post How to Make Good Photos With Any Camera assesses some considerations to avoid losing your message. Using this information alongside the guidelines presented in The Simplified System for Perfect Photography course will ensure that quality is maintained even if you enlarge.