Buying a beautiful f/2.8 lens zoom is tempting. Large apertures are always better. If you’re using primes, a f/1.8 or f/1.4 is even better. But is that expensive large aperture lens really necessary for your photography?
The first lens I bought next to the one I got with my camera was the beautiful white Canon EF 70-200mm f/2.8L IS USM. Its name is a mouth full, basically meaning it has that amazing f/2.8 aperture over the complete focal range. It is white, it is large, it is heavy, it looked good on the camera, and people were impressed by this huge white expensive looking lens.
I could have chosen a f/4 lens also, which is significant lighter, and half as expensive. It would have saved me a lot of money, money I could have used to invest in another nice lens. But I didn’t. I wanted to have that f/2.8, no matter what.
Since that time every zoom lens I bought had a f/2.8 aperture, except the Canon EF 17-40mm, which has only f/4. Every fixed focus lens I bought had an aperture of f/1.4 and I even choose to buy a f/1.2 lens also. These are amazing pieces of engineering, which all have their ups and downs. Yes, I admit, these lenses are not always the best performing lenses available, but I did not want any other lens. So, should you also invest in large aperture lenses that have f/2.8 or larger?
Before I try to answer this, I would like to sum up some reasons when you can benefit from a large aperture.
- Shooting a minimum depth of field with a nice bokeh
- Shooting in dark environments and still capturing enough light
- Being able to shoot faster shutter speeds in darker environments
- Making an optimal use of the auto focus capabilities of your camera
You probably would have guessed these reasons, and perhaps you can come up with a few more. But I think these are the most important ones. There are some other things to keep in mind regarding large apertures.
About Using Larger Apertures
Every lens has its optimum aperture, when image quality is at its best. The maximum aperture will always lead to a certain degradation, like light fall off in the corners, lens distortions, and reduced sharpness. Stopping down the aperture will increase the image quality very quickly. I know of situations where a f/2.8 lens at f/4 have the same image quality as the f/4 version of that lens.
If you never use a minimum depth of field, why would you choose a large aperture lens? A lot of landscape photographers never shoot at small depth of field and many studio photographers always shoot at f/8 or comparable. For these photographers there is no need for a lens with a large aperture at all.
In case you often shoot in dark environments, you probably would like to capture as much light as possible. Weddings, concerts and indoor sports can really benefit from a large aperture. But in those cases, you must take the small depth of field into account. It may prevent you from using high ISO levels, but it can lead to not enough sharpness and difficulties with focusing on the right spot.
Should You Buy a Large Aperture Lens or Not
Although it is a personal choice, don’t think you need to have the heavy and expensive large aperture lenses. Look at your preferences in photography before deciding to spend your hard-earned money on these lenses.
Do you like photographing with a razor thin depth of field, you might invest in these lenses. But if you prefer using the lens at something like f/8, you are better off with a lens that has a normal maximum aperture like f/4 or even f/5.6
If you are shooting at dark venues with relatively fast shutter speeds, you can benefit from a large aperture. But keep the thin depth of field in mind. If you prefer stopping down the lens, you don’t need that large aperture at all. I think you could benefit from a camera with a good high ISO performance instead.
Do you love to shoot a Milky Way at night, or landscapes underneath a starry sky? A large aperture will capture more light. But keep in mind these lenses will have a significant light falloff at the corners. If you want to prevent this, you might also choose a lens with a smaller aperture like f/4. Often a lens with f/4 has the same light fall off as the f/2.8 stopped down to f/4. You might want to check this out.
Lenses with a large aperture are often very heavy because these lenses require a lot of glass. Although this might be not much of an argument, it will make a lot of difference for photographers who like to travel. When you take the Canon f/2.8 trinity lenses with you (EF 16-35mm, EF 24-70mm and EF 70-200mm) you end up with nearly 4 kilograms. Change those lenses into the f/4 versions, and you will save almost 2 kilograms of weight. It might not sound a lot, but when you have to carry it with you for days it will make a big difference.
It Is Your Choice, and Yours Alone
As I already mentioned, the choice is personal, and you will have to decide for yourself if you need the large aperture lenses. If you really think about it, and if you are honest with yourself, you might find out you don’t need those expensive lenses, saving a lot of money. Or you might find out you really do need those, spending a more money than you anticipated.
Do you use the large aperture lenses, or did you decide to go for the f/4 and f/5.6 lenses? What are your thoughts on this subject? I love to read your opinion in the comments below.