If you are looking for information about image quality and megapixels, then your search ends here. Because in this article, we will explain everything about these two terms and how they are related to editing, printing, and exporting.
These days graphic creators only focus on megapixels, but that is not the only factor on which the image quality depends. What do you think will happen if you have 50 megapixels camera sensor, but your lens cannot keep up with it?
Let's break down megapixels and image resolution for better understanding.
What is Megapixels
The tiniest controllable units of a camera sensor are known as pixels. In simple words, a camera captures images due to these small components.
Numerous tiny pixels capture colors and light to form a digital image. A megapixel consists of 1 million pixels, to be exact 1048576 pixels. It means a 50 megapixels camera sensor has 50 million pixels.
What is Image Resolution
Image resolution depends upon the number of pixels a photo contains. More pixels mean high resolution and more detailed images. The unit to measure image resolution is pixels and megapixels.
To choose the right resolution, you should know about bitmap and vector format. If an image is in .png or .psd file formats, then it consists of pixels and detailed information. On the other hand, if the photo comes with a .jpeg or .tiff extension, then it contains compressed data that will not be clear when printed.
If you are using Adobe Photoshop to resize images, then select resolution 100% for maximum quality. To find the resolution of an image, multiply the width of an image with its height. For example, if an image has 2048 pixels in its width and 1152 pixels in height, then its resolution will be 2.36 megapixels
Generally, PPI (pixels per inch) is used to donate image resolution. Resolution is only one of the factors that determine the quality of an image. Other factors like lens quality, processor, and sensor all play a vital role in image quality.
If you are using Adobe Photoshop for image editing, then choose the print size before changing the resolution. Learn to export images with different resolutions so that you can send prints without any delay.
What is Print Size?
Print size means the number of inches an image contains. To find the print size, first, check your printer's dpi setting and note it down. For example, if your printer has 300 dpi, then 300 divided by pixels per inch will give you the width of an image in inches.
After knowing this value, open Adobe Photoshop and go to file > open to load your image into the Photoshop interface. Check the width of the opened photo using the ruler tool or document dimension option present at the top. Once done click on resize option to shrink the image.
Now, note down the new width value of your photo (now in inches) and divide it by your printer DPI setting.
Let's use our example here. If the opened file has 2400 pixels width and dpi is 300, then its print size will be 1.33 inch which means 15cm X 10cm format.
Where can I find the resolution on my photos?
If you are using digital cameras, then the camera manufacturer should mention it on its packaging or manual. If you are not sure of the resolution, then simply Google your camera brand name + resolution to find out the right info.
Some pictures also have their print size mentioned beside them. However, if an image's print size is different from the source picture's dimensions, then the photo will lose quality.
Where can I find my printer DPI setting?
Search for your printer dpi setting in its box or manual or check online by searching for "name of the manufacturer" + dpi. For example, Canon Pixma MX490 has a dpi rating of 9600 x 2400. So 900 X 300 = 2700 dpi which means Image quality – very good.
If your printer does not have a printed dpi rating, then the best way is to take help from its picture sample and evaluate it by yourself.
Best Resolution for Editing, Exporting, and Printing
When we talk about editing, the higher the resolution, the better. Set your camera to its max resolution, and it's better to shoot in RAW format (RAW gives you more options in editing than JPEG). The photos in RAW have much more detail to them, and you can edit them better during post-processing.
When you export files, you must have noticed that the image quality has regressed from what it was when editing the file. If you upload photos on a website, it's better not to use high-resolution pictures because it might take time to load, but the user will not wait for it and scroll past the image.
Social media platforms like Instagram and Facebook compress photos when you upload them on these sites to store millions of photos on their servers. Resizing your pictures to 2048 pixels when exporting them will do the job for you.
Always use 100% resolution while exporting pictures from Adobe Photoshop.
To get the best print quality, always use a professional printing service. You can also get your photos printed at online photo printing services like Shutterfly.com to get the finest prints for yourself and your family members.
When uploading photos on a website, choose JPEG format because it compresses files without reducing the resolution or quality of an image. Nowadays, most cameras have inbuilt settings so you can set it according to gear up when taking snaps (most digital cameras will give you different options when setting the file type).
Screen resolution on a display and photo resolution in terms of printing is completely different. A picture might look great on your desktop, but there will be a massive difference while printing it.
Like PPI, DPI (dots per inch) is another but similar term. It means if a print has a high number of dots per inch, the quality will be higher. You can set the DPI from your computer when printing; the conventional size is 300 DPI. You can increase the number, but below this, you cannot maintain the quality.
Photo size and resolution
When printing your photos it is important to understand what size you need. If you are looking to fit your digital photos onto a standard 4x6 or 5x7 frame, the resolution should be 300 dpi which prints around 3456 x 5184 pixels. If you want to print larger pictures for wall framing you can print up to 20x24 inches with 300 DPI image size.
Anything above this size will create pixelation in the image especially if the picture is enlarged more than 6x9 inch format.
If you are planning on printing an 8x10 landscape, then use 1440 DPI at 100% quality to get the best output. It's because this photo size requires 1,440 x 2,560 pixels resolution which equates to 10,368,000 individual pixels.
The same size can be used for an 11x14 or a 12x12, but the pixel count goes down to 3,328,000. In case you plan on printing a 15x15 landscape frame, then use 600 DPI and 2,880 x 4,640 pixels resolution.
When we talk about using resolutions that are lesser than 300 dpi we cannot expect our pictures to look as great as they would be if they were printed at the standard 300dpi. However, there is still no harm in choosing high-resolution images because even now digital cameras have excellent image quality even when they shoot at 240dpi.
What should I do if image dimensions and print size are different?
When you visit a photo printing website, just choose the "upload photos" option and upload your images clicking on "upload now". Then click on the advanced options button present at bottom of the page. Now, select a paper format such as A4 or 8x10 inches then enter the desired resolution in pixels per inch box.
After doing this, upload your pictures again and order them for delivery. For instance, if you uploaded an image with 900 PPI resolution before but want a small picture frame that has 300 dpi, then you should upload it again by changing the PPI to 300.
What if I don't want my pictures to lose quality when printed?
To preserve image quality, make sure your original source media is of high resolution. If not, then find an alternative way to print low-resolution images without compromising photo clarity. You can also try Google's free online photo editor Picasa which lets you save edited photos after editing in .JPEG format with maximum photo quality.
If you are using a standard printer for printing pictures, then use good paper and proper picture settings to achieve desired results. For instance, photo paper or glossy color printing requires 180 – 220 gsm weight paper and good resolution for producing colorful prints. Also, use photo paper which is specifically made for inkjet printers.
If you are using a photo printer, make sure the image size matches the paper format. After adding photos to your computer, open Picasa, check image properties, and adjust them accordingly. You can also use external software like Roxio PhotoSuite or Corel Digital Studio to resize images before printing.
Final word
The best resolution for printing your photos is certainly 300 dpi. You can also print your photos at high resolution but not exceeding the optimum size mentioned above. However, remember that the larger the print size, the lesser resolution you should use.