Jim wrote to ask about exposure, color, and sharpness results on photos taken on his Canon 350D/XT. Here is what I wrote in reply to his original email:

First of all, in regards to exposure the histogram display is your friend. I have my XT set to display the very small version of the image after exposure along with the histogram display. The histogram can tell you quite quickly whether your exposure captures the full dynamic range. In fact, I often use the first shot as my light meter – I let the camera make the first exposure in aperture priority mode and then look at the histogram. Then I frequently switch to manual mode and set aperture and shutter speed based on what I saw in the histogram.

If the full dynamic range will not fit into the histogram display – in other words there is a sharp cutoff at the bright and dark ends of the scale and the highlight warning flashes the display – I will give priority to avoiding blowing out the highlights. In other words I close down or increase shutter speed so that I avoid losing detail in the bright areas, even at the expense of seeing the curve shift toward underexposure. When this happens there are still a couple of things you can do to salvage the shadow areas, especially if you shoot RAW mode: you can bring up the dark areas in your software on your computer if they aren’t _way_ too dark, or you can shoot multiple exposures of the scene (obviously on a tripod) with some optimized for highlights and others for shadows and then combine them in Photoshop. (I did that in a major way to create the Pacific Sunset from Windy Hill shots I recently posted.)

Are you shooting in RAW mode or shooting .jpg files? I always shoot in RAW mode because it does not compress the image data at all – it basically dumps the photosite data into a file. (Hence, “raw” I suppose.) RAW files contain greater dynamic range and give you more room to make post-camera corrections in software. In fact, you really _must_ make a number of post-processing adjustments in order to get the most out of RAW files. Plain unprocessed RAW files are not very impressive and, in particular, they are not very sharp looking. (jpg files may appear sharper straight from the camera due to in-camera sharpening and other automatic adjustments, but they cannot be improved much beyond this point.)

In general, when I convert my RAW files (use the Adobe Camera Raw component of Photoshop) I increase the contrast and saturation a bit (the exact amount varies), decrease the exposure (and sometimes compensate by adjusting brightness) so that highlights are not burned out, adjust the shadows setting to the lowest black level, and adjust for chromatic aberration if necessary. Yes, a lot of steps! But that’s not the end.

Once the file comes into Photoshop there is still a lot of work to do. At a minimum (in all but the rarest cases) I adjust levels so that the dynamic range of the image fills out the available dynamic range of my printer. Depending upon the image I may also make adjustments to curves, saturation, and so forth. And then, in classic style, I dodge and burn as necessary. On some images I employ other more exotic techniques (local adjustments to contrast, levels, saturation) to get what I’m looking for.

So a short summary:

No, I don’t use separate light meter, but I do use the camera

as a meter by means of the histogram display.

I try to get the histogram curve to fit into the middle of the

display and avoid blowing out the high end especially. (A good

curve goes _to_ the high end but not beyond.)

If the dynamic range is too great I take multiple frames at

different exposures and combine them later in software, or

if the problem isn’t to severe I can rescue the shadows from

a single exposure in the RAW converter.

I always shoot RAW.

Post-camera adjustments to levels, exposure, saturation,

contrast, and (especially) sharpening are necessary when

you work with RAW files.

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