I've always worked very hard to avoid absolute white and absolute black in my photos. But I think maybe I'm working too hard. When is it appropriate to have blown highlights / shadows? Are there examples of photographers who make use of these extremes to good effect?
I would say that blown highlights or blocked blacks are perfectly acceptable if it helps you meet your artistic goals! There are different and often conflicting aspects of photography that sometimes make it difficult to judge this kind of thing. On the one hand, you have the "technicals", the aspects of mechanics and technology, telling you not to blow out your highlights. Its "bad" because they can't be recovered with digital, and there is a bit of a taboo about it. On the other hand, you have the "art", the aspects of vision and style that make a photograph all you. At times, the artistic desires of your minds eye are at conflict with the demands of technology.
When push comes to shove, I would say go with your artistic side. If you visualize something that moves you, capture it how you see it. If that means blocked blacks or blown highlights, including a bit of sun flare, allowing some vignetting, then so be it. Ultimately, art is what photography is all about...not meeting some logical definition of what photography should be from a technical standpoint. Use the tools at your disposal to expose your vision, and push the limits of those tools to bring about your own personal style.
Jrista summed it up nicely, but I’ve added some examples of my own to show why you don't necessarily need to worry about highlights unless it is a technical or aesthetic requirement.
Digital sensors and even film cannot capture the dynamic range that the human eye can see, along with the processing the brain performs. Sometimes there is too much contrast in an image and you will have to choose whether to expose for the highlights, shadows or mid-tones based on what you want to achieve.
For example, I am the subject of this photo. The interior is noticeably darker than the sky and the environment outside, so I chose to expose for myself and the room I was in to bring viewer attention to me and the camera. This resulted in the exterior being overexposed. I might have been able to underexpose the image a little and boost the shadows when processing the raw file but I decided to just expose properly on myself and let everything fall where it may.
A similar situation here. The "subject" is the statement, "Jack Lives Here" on the mug, so I decided to expose at +0 EV on the mug and the rest of the scene fell where it did.
I think this goes back to (just like learning Jazz) you have to learn the rules before you break them. I was trained to not crush the blacks and no paper based whites... but sometimes a pictures just screams for some crushed blacks in the shadows. As long you can justify it from an artistic standpoint and you KNOW that they are crushed and not just randomly moving sliders around... i say go for... I know I sure do.
Black and white is a prime example, as it lets you work contrast much more aggressively. It's not really black and white if you have no true black or true white!
So, if you have a shot that you feel doesn't make the grade in colour, try a B&W conversion. Avoid simple desaturation and go for Channel blending or Calculations for punchier results.
As dpollitt suggests, RAW can save your bacon and, in combination with a decent RAW processor, often lets you grab back just a little detail that you thought might have been lost.
I would say it is always OK if you have no other option but to blow out highlights or underexpose shadows to get the shot. It is better to get the shot then to throw it out because lack of technical prowess.
A possible solution is to shoot RAW format, or shoot multiple exposure to get around the limitations of your equipment.
The rules in photography are just basic guidelines.. they don't necessarily have to be followed to get a great picture (although they help to get good picture if you don't know what you are doing).
Some cases which I find it completely acceptable to have blown highlights/shadows:
- black and white .
- To hide details ( E.g. http://blog.chasejarvis.com/blog/2011/05/deconstruct-this-photo-4-0-revealed/ .. this page also nicely lists why he did what he did)
- Any composition with sun flare.
- Silhouettes. etc etc
For portraits when dealing with a high contrast scene I often expose for the skin tones and let the rest be. This can produce some nice "high-key" photos.
For landscapes I try to avoid the blinkys by using a filter, because a white sky isn't interesting, but a blinky white sun can be.
I am similar to you in that I'm a recovering highlight-phobe, but it's OK, white and black are colours too and should be represented in photos!
White blown background is desirable on product shots, unless you want to show off your light tent.
Black shadow areas are normal in photos made in dark with little lighting, especially light paintings. Silhouettes look best when they are black.
I would just point out another consideration, that I haven't seen mentioned in the answers. When looking for blown out highlights and shadows, beware also of the posterization (i.e. blotches of color coming from compression or lack of available hues) that may come around under-overexposed areas, especially following JPEG compression, and when you try to recover highlights or shadows.
These may catch the eye more than the highlights themselves, and rarely look "right".