Again, why “fast” lenses?
A tip for newcomers to SLR photography.
I often hear: “Why do I need so-called “fast” lenses – like the 50mm f/1.8 lens Michael keeps talking about? Surely my 18-55 lens also covers 50mm?”
Well yes it does. But:
- Less sharply. A “prime” (i.e. non-zoom) lens is sharper.
- A prime lens is also smaller and lighter.
- And especially: the prime lens has a lower minimum “F-number” – i.e. a larger aperture. The lower the “F”-number, the better. Your kit lens is f/3.5-5.6 (meaning zoomed out it can go as low as 3.5; zoomed in it can go only as low as 5.6. The 50mm f/1.8 can go as low as 1.8).
Why is this important?
So in today’s class I took two shots of a student in available room light. One at f/5.6, and that is what you would get with your standard “kit”-lens. It looks like this:
Two things happen:
- Because of the small aperture (high “F-number”), the camera has to keep the lens open for a long time. This means that unless I use a tripod and tell the subject not to move, in indoors light I will get camera shake (the shot needed 1/10th of a second). And sure , do.
- The lower the “F” number, the shallower the depth of field, i.e. the blurrier the background. The higher the F-number, the sharper the background.F/5.6 gives a background that is somewhat blury.
Now look what happens when I use an aperture of f/1.8 (for which you need a lens that can do that, like the 50mm f/1.8 lens):
Much better – a pretty dramatic difference on both counts!
So the best way to immediately get great portrait shots is to:
- Get yourself a 50mm lens. On most cameras this is simple; do note that on a Nikon D40/D60/D3000/D5000 you need to manually focus this lens (that is why I recommend Canon cameras at the entry level).
- Learn Aperture Priority mode (A/Av) and use a low “F-number”.
- Turn the camera sideways and get close!
Have fun.
(Wow, three numbered lists in one blog post!)
That look over the shoulder
One common sexy model look is the “look over the shoulder”.
Like here, in this shot of Nemo, a somewhat Rubenesque but nevertheless pretty model:
In an “over the shoulder” pose women can look over either shoulder, but for men, if the shoulders are angled, avoid them looking over the higher shoulder. This is a feminine look.
As so often with available light portraits, in the shot above I used my Canon 7D with:
- a 50mm lens, which on the 7D crop camera is really equivalent to 80mm
- 2000 ISO (on auto ISO)
- 1/60th at f/1.4
Yes, you can take pictures on a 7D at 2000 ISO and have them look just fine.
Bright pixels are sharp pixels, but also, bright pixels are noise-free pixels.
(And you know to focus accurately, using one focus point, aimed at the closest eye, right?)
Misc
Backgrounds and sharpness and white balance: oh my!
I thought I would chat about some of the things that go through my mind when doing a portrait, like this one last night:
Questions like:
- What camera and lens? In this case, the Canon 7D and a 50mm f/1.4 lens.
- What settings? Well, manual at 100 ISO, 1/125th second, f/5.6 is my standard start point, as it was here.
- What lighting setup? In this case, a standard two main lights (softbox main light on camera left, umbrella fill light on camera right) with a snooted hair light behind left, and a gridded gelled background light. Note that while the main lights were monolights, the background light was a small speedlite fired by a pocketwizard through a Flashzebra hotshoe cable.
- What lighting ratio? In this case pretty flat, but usually more like a 3:1 key:fill ratio.
- What body position? Usually angled, in this case toward the softbox.
- What head position? In this case, straight on since the subject wanted it that way.
- What colour background? In this case I used a blue-green gel from the new Honl Photo “Autumn” colour gel set.
- What viewpoint? I carefully choose this by moving myself left and right, up and down, until the person looks best to me for the portrait wanted. If in doubt, I take multiple views and choose later.
- What white balance? I set it to “Flash”, even when shooting RAW, just so I get OK views on the back of the camera.
That’s all there is to a quick snap like this, which took a few minutes – if that.
Snap
Photography is about composition/subject + moment + light. I reckon I got several of these right here:
From earlier this year. Using a 35mm lens on a 1.3 crop camera (meaning it’s 50mm), set to f/2.8 at 1/160th second.
Moral of the story: a “standard” lens is great. This is equivalent to a 50mm lens. Do take lots of pictures and do not forget the “moment” aspect.
Eye
Portraits? Then use a 50mm f/1.8 lens (affordable, fast, sharp) and shoot in Aperture (A/Av) mode with it wide open (preferably by window light).
Look at this recent available-light shot of a student:
This gets you the dual advantages of low-light ability (no flash needed!) and blurry backgrounds. As long as you make sure the closest eye is the sharpest.
So, set your camera to the widest aperture (the smallest F-number), use high enough ISO (indoors this might be 400-800 ISO), and use one focus spot, and aim that spot at the closest eye. Click!
Do I need a fast lens?
When students ask me “should I really buy a fast lens?” (For beginners, that’s a lens with a low “F-number”, like f/2.8), my answer is “it depends.”
What are you shooting? Landscapes (no need for a fast lens, since you will shoot at f/16 or above) or nightclubs (which need a fast lens for low-light abilities), portraits (which need a fast lens for blurry backgrounds) or sports (which need a fast lens for fast exposures)?
And if you like blurry backgrounds, does it make sense to get a pro lens like an f/2.8, or is my kit f/5.6 lens enough? That’s an easy one to answer. It depends. On whether you like this, taken yesterday during a course at f/5.6:
..or whether you prefer the same shot at f/2.8:
You decide. View them full size to really see the difference.
Know that every stop faster (from 5.6 to 4, or from 4 to 2.8) doubles the lens price. But if you like the blur (“Bokeh”) in the bottom shot, there’s no substitute for fast.
And I did not say expensive – at least not necessarily so: while some lenses like my f/1.4 35mm cost $2,000, an excellent 50mm fixed (“prime”) f/1.8 lens (a “nifty fifty”, which on a crop camera is great portrait lens) can be had for as little as $150 or less.
So yes, low f-numbers make a difference and that’s why photographers are willing to pay lots of money for them. But don’t worry: good lenses keep their value.
f/1.8 lens, stopped down, shot with f/1.4 lens, open
I have many times recommended 50mm f/1.8 lenses, and I’ll try to inspire you once more to go out and get one right now. Most manufacturers have a cheap lens like this:
As you will have heard me say many times, this lens is cheap, small, light, fast and sharp.
Ideal for portraits or for low-light subjects or images where you want to dramatically blur the background. If this lens is not in your kit yet, I recommend you add it immediately.
As you will have seen in the previous post, I shot Prof Dawkins yesterday with just sich a lens (my 50mm f/1.4).
Dawkins
I photographed Richard Dawkins tonight. In the sold-out Bader theatre in Toronto, where he introduced his new book to an enthusiastic crowd:
Usually, theatre lighting is quite simple – if you get to sit in the right place. Since my son Daniel and I sat in the very front row, today was no exception. The background is dark but the subject is lit brightly:
I did not need more than 400 ISO, which gave me 1/100 sec at f/2.8. In manual exposure mode, of course.
“No flash“, the slightly inept people from the publishing house (who did not believe I had talked to their colleague on the phone earlier – Simon and Schuster Canada, you lost out on some free shots!), said time and time again. (The Dawkins web people aren’t very responsive either: four attempts to contact them. to multiple email addresses, offering free coverage – and zero responses: instead, I helped their own shooter, who was an ‘emerging pro’ and asked for some advice).
No problem!
The only problem was focus. My 50mm f/1.4 lens front focused on the 1Ds MkIII by at least 6 inches, which is disastrous. I had to adjust it to a setting of “+17″ (out of a possible 20!) in the ten or so minutes before prof Dawkins arrived. The 35mm f/1.4 and 24-70mm lens would not properly focus at all in this light (they were consistently way off), so while I switched many times, I kept coming back to the 50mm lens with +17 adjustment.
One day Canon will make a camera that focuses well. Perhaps. I am not holding my breath.
Anyway, I got some nice shots. Photojournalism is never easy, but sitting about 10 ft away from Richard Dawkins makes up for a lot.
(A few more shots here)
Nifty Fifty
One lens that should be in everyone’s kit bag, however cheap your camera or however little you want to spend on equipment, is the 50mm lens. A lens they used to call the “nifty fifty”. I have mentioned this lens before.
Many manufacturers have a cheap 50mm lens – Canon and Nikon both have a 50mm f/1.8 version that costs less than $200. This Canon one costs only about $130:
So it can’t be any good, then?
Wrong. It is very good. On film cameras this used to be called a “standard lens”. Now, on crop factor cameras, this lens has come into a new life as a portrait lens – on a Canon Rebel, for instance, with a 1.6 crop factor, this is like an 80mm lens. Great for “headshots” portraits.
And the nifty fifty is a fast lens – “fast” being somewhat of a misnomer that just means “has a low f/number”, so it allows lot of light in, and allows for selective depth of field (only part of your picture is sharp).
Which in turn allows you to take pictures like this, using only available window light:
Notice that at f/2.0 you get very selective focus. This is not bad – it can be used for effect.
Make sure, however, that if you do this you focus carefully, using one focus point, on the closest eye. Looking at the picture above in detail:
If you like that look, and have a window, go get yourself a 50mm lens today.
Black and white…
..is underrated, I think; especially for portraits. Or else why don’t we do it more?
A good black and white photo can full of character; moody, even. Especially in portraits, where the absence of colour means the absence of distraction, and the ability to concentrate on the essence of the person.
35mm f/1.4, 1/30th sec, available light
For a good B&W picture, you need to realize that the background and the subject need to contrast, and that where we see clear colour contrast, in a B&W picture we may see none.
B&W works especially well where colour distracts. It can work where the subject either has blacks and whites, or is high-key or low-key. A good B&W picture can be a study in shades of grey.
35mm on 1.3 crop camera, f/8, 1/200th sec, strobe in umbrella.
When I shoot black and white, I do the following.
- I shoot in RAW. This is essential.
- I always set the camera to “Black and white” also. Even though this has no effect on the RAW images, it gives me a preview of roughly what the image will look like.
- I ensure I do not overexpose the whites, but I do “expose to the right”. I.e. until the histogram almost hits the right edge.
- Then I finish the image in Lightroom. In the DEVELOP module, I use the GRAYSCALE adjustment in the HSL/COLOR/GRAYSCALE tool. This gives me the easy ability to change different colours’ brightness.
This last step in particular has made B&W a practical endeavour once again for a busy guy like me. You know what they say: “no rest for the wicked”. And if I were, oh, 35 years younger I would add a “LOL” at the end of that.
Finally: B&W does not have to be moody – or rather, the mood does not have to be serious. Here’s my friend Keith, and his happiness and intelligence, big parts of his personality, really shine though here:
50mm f/1.4, 1/1000th sec, available light
Go ahead, give it a go. Have fun shooting B&W. And because you are shooting RAW, you can always go back to colour at the touch of a button.
A very hard softbox.
Try this next time you want a person lit by a softbox and you have no softbox:
Use a computer monitor.
Display a white background (e.g. open a word document) and hey presto: a big and efficient softbox. And if you use a fast lens (e.g. a 50mm f/1.8), it’s plenty bright as well.
And you can even use it as part of the picture:
Tell me that’s not cool: photographers improvise.
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