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Basics Stage 3 :
Quality Settings
This is usually at the top of the list on the settings menu on DSLRs.
So what should you set?
If you care about your photographs set the camera to RAW.
That will get you the quality you expect from your DSLR. I'll explain why in a minute. Most cameras also let you choose to have a JPEG of each image too, so if you're not sure about RAW, choose RAW plus a Large, Fine JPEG.
As nearly all your final images will be JPEGs, many people think why bother with anything else?
To understand why RAW is better, you have to learn a little bit about how JPEGs work.
JPEGs
It stands for Joint Photographic Experts Group and JPEGs are the most common file type for photographs because they can store a 35 mb photograph in a 4 mb file, which is magically 35mb again each time you open it. This is called compression, and it’s brilliant, so long as you remember that JPEGs are a form of “Lossy” compression. That means each time you save a JPEG it changes slightly. You lose a little.
The experts got together to cure a problem – digital photographs had started to take up a lot of space. Up 'til then TIFs were the way to go, but TIFs record every pixel in a picture exactly, so a 35mb picture is a 35mb file. Everyone's hard disk began to fill up almost overnight, so we needed a way to make pictures smaller. There were forms of “Non Lossy” compression around – ZIP files can compress a TIF, but only by about 10 – 15%. Not nearly enough.
Their answer was a new type of compression – Rather than recording the exact level of blue in every pixel of a picture with a blue sky, why not just say this area is this shade, another area is a slightly darker shade and so on. As most pictures have areas of similar colour or tone, this saves a huge amount of space. You can even choose how accurate the description is by setting the compression level from 1 – 12, with 12 being the best. (large fine will usually be an 8 or 10) JPEGs are an amazing achievement, but if you want the best quality images, you have to use them with care.
JPEGs are Great, BUT.....
If you set your camera to record only JPEGs you immediately lose quality. Most DSLRs record an image as a 12 or 14 bit file and for JPEGs convert that to 8 bit, permanently discarding the rest, they then apply a white balance setting (if the camera gets it wrong – tough, no way back) a tone curve (ditto) and some sharpening (also ditto), before compressing the file. Think of all of that as writing a detailed description of what you started with, and then discarding the original. Does that sound like a good plan? The little symbols on the menu above mean L = Large, M = Medium etc and a smooth curve means high quality, while a jagged curve is meant to show you what you’ll get if you use low quality.
If you then take your JPEG into Photoshop adjust it a little and save it, you loose another level of quality. Your JPEG is now a description of a description. Make any more changes and save it again and it's a description of a description of a description. Use lower quality settings anywhere along the way and it would be a brief description of a brief description etc...
RAW files record exactly what the camera's sensor sees without any processing. Everything – all 12 or 14 bits, every bit of tone or detail.
This gives you the equivalent of a digital negative which you can then process very easily to make exactly the JPEG file your camera would have made, or you can make adjustments that, back when I started taking photographs, would have seemed impossible.
(No I didn't know Fox Talbot. Well not very well...)
Stage 4 : RAW Workflow
David Gold
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