Lens hoods: Are naked lenses ruining your images?

“UGH!” (Smacks hand against forehead) “I should have used a lens hood!.”

Nov. 12, 2008 Spend time at any event where photography enthusiasts congregate and you will notice plenty of naked lenses…lenses without lens hoods. That’s rather strange, when you consider that nearly every quality lens ships with a custom designed lens shade made expressly for that lens. It isn’t a matter of being able to afford a hood; it is nearly impossible to buy a Sony Alpha lens without a matched shade. Most quality glass from other makers also include a hood with their lenses. So all those photographers already own lens shades; they simply don’t bother to use them. Too many photographers treat lens hoods as part of the lens packaging — something to be dropped back into the box and packed away into the closet.

There are certain situations where a lens shade is unnecessary, or even detrimental to making good images. I’ll discuss the specific conditions when you shouldn’t use a lens shade in a moment. First, however, I want to look at why you should attach a hood almost every time you take a lens out of your bag.

Kill the glare, stick a shade on it

Most photographers know that lens shades are intended to exclude glare and reduce hot spots. In addition, lens shades increase contrast, improve sharpness and retain color fidelity. Consider the fact that many photographers spend large sums on top-quality lenses because they know that excellent glass will produce better images. Yet many of these same photographers can’t be bothered to attach a hood, even though that hood is essential to getting the most from that expensive lens.

Lens shades come in a wide variety of shades and designs. The best hoods are designed expressly for the lens they are being used on.

Flare comes in two varieties

There are two kinds of lens flare. The first is obvious flare. It is often referred as ghosting because the appearance is akin to the images the paranormal investigators get excited about. It is characterized by distinct ghostly areas caused by light reflected off the interior of the lens. These reflections are usually visible in the viewfinder, although sometimes you won’t notice the flare until you process images on your computer. Most of the time this type of flare is deadly to your images, because it is nearly impossible to repair the effects of obvious flare.

The other type of flare is more subtle. Instead of a prominent ghostly area, the reflection occurs across all or most of the surface of the lens’ front element. The result is a subtle loss of contrast and color fidelity. You might not even realize that flare has affected your image, because the difference is so delicate. Yet, the difference exists. If you could eliminate the flare, the image would look sharper and richer.

Suppose a respected lab announced that a specific lens had five percent better contrast and sharpness than any other lens in it’s class. That lens would immediately become a highly lusted-after optic. Photographers would speak of it in hushed tones and be willing to spend huge sums of cash for the privilege of saying they shoot with that lens.

Yet, although we know that use of a lens shade can dramatically improve our photos, many photographers can’t be bothered to use one. Spend hundreds of dollars on a lens that provides sharper images with better color? Of course. Spend ten seconds to attach a lens hood to improve sharpness and color? Sorry, just can’t spare the time.

Hopefully, you already use a hood whenever applicable. What if your original hood is lost or broken? You have several options. If the lens is still in production, you can always order a new one from the manufacturer. This is often the best route, because you know the hood will be matched to the lens. Unfortunately, original replacement hoods don’t come cheap. In some cases, the list price of an original equipment hood might be twenty percent as much as a complete new lens — a fairly high sticker for a plastic cylinder or stamped piece of aluminum.

I lost my hood, now what?

You could look for a used hood on one of the online auction websites, but if the hood is for a popular lens, you may find it difficult to secure a second hand lens shade. That narrows your choice to one of the many aftermarket hoods available. Unfortunately, one size of hood definitely doesn’t fit all focal lengths. A longer shade will be more effective, but long hoods cannot be used with wide angle lenses because the hood will cause vignetting. Zoom lenses can be even more problematic, since it may be difficult to find a generic hood that offers sufficient sun protection without vignetting at all focal lengths.

Aftermarket hoods are available in metal, plastic and flexible rubber. A generic hood may not be as fully effective as one specially tailored to a specific lens, but the aftermarket shades are much more affordable.

One final source of replacement hoods are printable hoods that can be downloaded from the internet. Type “printable lens hoods” into your favorite search engine and you will find dozens of paper hoods designed expressly for a wide variety of lenses. Print them on stiff card stock, cut them out and attach them to your lens.

So when should you forgo a lens hood? There are times you might want to introduce lens flare as a creative element. Hollywood movies often go out of the way to show flare effects in establishing shots. You may want to include this technique in your own portfolio.

When shooting flash, use a hood with care

Finally, use care when using a lens shade with electronic flash. Lens hoods can block the light from a hot-shoe mounted flash unit or a built in popup flash. Generally this isn’t a problem with longer focal length lenses, but with a wide angle lenses, there is a real possibility that the shade will cause a dark shadow at the bottom of the frame. It is a good idea to check how your wide angle lens hoods perform with hot-shoe mounted flash units.

So do use your lens shade? Why or why not?

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Tom Bonner