This is non-negotiable! When delivering pictures to clients from a wedding or photo shoot, only give them the best full resolution pictures with JPEG compression! Also give clients the pictures without any watermarks on them as well because nobody wants to see an annoying text or a distracting logo on a photograph anyways.
Higher resolution means more detail, bigger print size, and a more grandeur look! To give you perspective, the common smart phone will have a near resolution of 3 million pixels and your 4K TV will have over 8 million pixels. That is a lot of detail, but professional grade camera capture pictures at a stunning minimum 24-50+ million pixels! At that resolution, you can create huge prints with insane detail! Also being able to see these pictures on a high quality screen up to 8K is also spectacular!
You should capture your images in a minimum 12-bit raw for a total of 69 billion colors. Personally, I capture my photographs in lossless 14-bit color depth for a total 4.4 trillion colors, so I can enhance the visual look of client photographs. Some super expensive cameras (such as cinema cameras used in Hollywood) can even achieve 16-bits of color for a total of 281 trillion colors. Once the editing is finished on the images, compress the pixels down to 8-bit JPEG (17 million colors) for the best compatibility, which removes unnecessary colors that the human eye is not capable of seeing. This process is universally accepted and does not alter the image quality.
Fun Fact: bit depths are binary variations by digits. 1-bit are variation 0 & 1 for a total of two. 2-bits are variation 00, 01, 10, & 11 for a total of four. 3-bits are variation 000, 001, 010, 100, 110, 101, 011, & 111 for a total of eight. I am going to stop now before I drive myself crazy!
The mathematical equation: They are calculated by computing binary count to the power of the bit depth. To include color, add the power of the channel count (e.g. RGB) to the equation. For example: 8-bits = (2^8)^3 = 16,777,216. Change the last exponent to 4 for a total of 4.3 billion if you also have an alpha (transparent) channel in your image data (only applicable for editing and CGI purposes).
JPEG compression was created in 1992 and is universally accepted for a wide range of applications, such as web use or printing! Using JPEG is a very popular file compression for images, as they are small in size while containing a superb image quality.
Fun fact: JPEG stands for Joint Photographic Experts Group.
Using delicate autofocus systems, state-of-the-art glass (many Nikon lenses I use may include FL, FLC, ED, N, SIC, and HRI elements) can increase the clarity of the image. Just make sure you are also using proper techniques to achieve flawless sharpness!
WHAT ABOUT UNCOMPRESSED IMAGES?
Sometimes you can also provide clients uncompressed 10-bit (1 billion colors) TIFF image copies built from the lossless RAW data. You can even provide more bits if you really want too, but that is uncommon. Usually, the only reason clients would need a TIFF version of a photo is for extra-large format printing and cinema displays. In the past, I have allowed clients to purchase TIFF images from the digital section from my online gallery. Please note that uncompressed images can be up to 250mb!
Fun fact: TIFF stands for Tagged Image File Format.