Product photography and packshot image file formats
Sunday, 6 September 2015 | Admin
There seems to be a limitless range of different image file formats available. Luckily most product photography situations only uses the following few:
JPEG - Joint Photographic Experts Group (JPEG) normally shown as imagename.jpg is the most popular format used to display product photography and packshot images on the world wide web. JPG’s support 24-bit colour which means they can produce a colour pallet of up to 16 million colours, making them ideal for continuous toned product photography photographic images.
JPEG images can be compressed easily to a small file size helping your web pages load quickly. However you need to be aware that the more compression you use the smaller the file size but the lower the quality of the final image.
High resolution JPG’s are also commonly used for print. They have one main negative in that they can not be used with a transparent background meaning you will always see the image background around the product.
As jpg’s use compression, always resize the image from a duplicate of your original as re-saving an original jpeg multiple times in a chain will produce a lower quality due to the effect of multiple compressions.
PNG-24 - Portable Network Graphics (PNG) normally shown as imagename.png may be used on a web page instead of a JPG. Similar to JPG’s the PNG24 format supports 24-bit colour which means they can display a colour pallet of up to 16 million colours. Making them ideal for continuous toned product photography and packshot images.
PNG may also retain a higher level of colour information than JPG, as unlike JPG’s they are not automatically compressed. However, you are unlikely to see any real visual difference under normal conditions unless the JPEG is heavily compressed.
Because of the lack of compression the PNG-24 file size is normally larger than an equivalent compressed JPG and therefor may have a detrimental effect on your web page load speed.
The main advantage of the PNG format is that unlike the JPG it preserves transparency in the image’s background allowing a product to float above a websites page background colour.
GIF - Graphics Interchange Format (GIF) normally shown as imagename.gif can be used like PNG to display images with transparent backgrounds but as it only supports 8-bit colour and a limited 256 colour pallet it is not normally a good choice for continuous tone pictures.
It can however work well with graphics such as a logos. We sometimes use GIF to produce product animations that can run without needing to embed any code in your web page.
PNG-8 - Portable Network Graphics (PNG) normally shown as imagename.png may be used on web pages instead of a gif. Like a gif it only displays up to a maximum of 256 colours so is not a good format for continuous toned photographic images. Neither dose it support animation.
TIF - Tagged Image File Format (TIF or TIFF) normally shown as imagename.tif is in our opinion the ideal format for product photography images which are going to be commercially printed.
It is a very flexible image format that holds more colour information than most other formats and can be exchanged between all computer platforms and nearly all web, design and photo-editing applications.
Tif is a very high quality format that supports both large RGB and CMYK colour spaces and can easily be converted to other page layout formats as needed.
PSD - Photoshop Document (PSD) is the default and only high quality file format that supports all photoshop features. For this reason we use it as our main working file format for product photography and packshots, and then save JPG, TIF or PNG files from it for delivery of the final work.
RAW - The raw format is the image file which is produced by the camera and contains the data from the image sensor. It is often referred to as a digital negative because they are not yet processed and therefore can not be used on the web or in print. In out normal work flow we output RAW files as PSD format to enable retouching in Photoshop, then normally supply the finished product photography and packshots as JPG, TIF or PNG format.