I have been primarily shooting with a Canon 18-135 f/3.5-5.6 for several years now, and I am not completely satisfied with it. The problems I have are:

  1. A bit too wide on the low end
  2. A bit too short on the long end
  3. Not enough Bokeh (I think, continue reading)

I mainly shoot my kids playing outside, and have occasionally started to take pictures for friends and family (out door shots like the one below).

I am shooting with a cropped sensor, so even though the lens is more like a 28-200, It isn't quite fitting my needs. I routinely wish I had something around a 50-250 (adjusted which is around a 28-150 on a full frame) with great bokeh.

I have been searching around, and the closest I can find is the Canon 18-200 f/3.5-5.6, which at least provides a bit more reach. I find it rather difficult to get a nice out of focus background with my current lens, and I am concerned that 5.6 isn't shallow enough.

From what I understand, if I am shooting with a wide lens then I want to be close to the subject for good bokeh. On a long lens I want to back up, and get the subject far from the background. I try this all the time, but it doesn't seem to work out how I want it.

Am I just shooting with the wrong equipment? Do I need to comprise on focal length range, and just find something with a really large aperture?

enter image description here
40mm f/5 1/200sec

  • The link is a blank white page. No image is visible.
    – Michael C
    Oct 13, 2013 at 21:32
  • 5
    possible duplicate of How can I get dramatic shallow DOF with a kit lens?
    – mattdm
    Oct 13, 2013 at 21:43
  • 2
    Fixing the "too wide" problem is easy: don't use it at focal lenghts that you don't like :) The "too short" problem is another matter.
    – Francesco
    Oct 13, 2013 at 21:46
  • @mattdm I'm not sure it is. I am not really asking how, but if I am using the right equipment
    – user6189
    Oct 13, 2013 at 21:50
  • @Joe -- it's not exactly te same question, but the answers to that one necessarily answer this one.
    – mattdm
    Oct 13, 2013 at 22:23

10 Answers 10


To get the result you want, you need a wider aperture or a larger sensor. If you are already separating the subject from the background as much as is practical, shooting at the lens' widest aperture setting and still not seeing what you want to see then you've reached the limits of you current gear.

At the minimum for longer focal lengths you need an aperture in the f/2.8 or lower range. For shorter focal lengths you probably need a prime with an aperture at f/2 or wider. On your APS-C body I would consider the EF 50mm f/1.4, the EF 85mm f/1.8, one of the 100mm primes, or the EF 135mm f/2 L. If you've just got to have a zoom, the EF 24-70mm f/2.8 L II is an excellent choice but it is pricey. Image quality is virtually identical to the much cheaper 50mm f/1.4 when the 24-70 is set at 50mm, but it is also equally good from 24mm to 70mm. The Tamron SP 24-70mm f/2.8 Di VC is not quite as good, but a lot more affordable and also adds Vibration Control, Tamron's IS equivalent. The APS-C only EF-S 17-55mm f/2.8 IS is also an excellent normal zoom lens, but may be a little short on the long end for you unless you get a separate telephoto lens. For a telephoto lens you should consider one of the EF 70-200mm f/2.8 variants.

For how the sensor size affects Depth of Field (DoF) see this answer. For a comparison of the various 70-200mm options for Canon bodies see this answer.

  • I second the EF-S 17-55 f/2.8 IS. You can pick up a Sigma variant for just over $400.
    – Tim
    Feb 19, 2016 at 19:00
  • I've had a Tamron SP 17-50mm f/2.8 Di II since 2009 that I've been very happy with. The warranty finally expired a couple of years ago (never had to use it). I rarely use it any more only because the vast majority of my work below 100mm focal length is now FF. If you get a well adjusted copy of the Tamron I think it beats the Sigma a bit optically. My Tamron performs just as well as my EF 17-40mm f/4 L on a crop body, but doesn't have quite the same build quality. Tamron lenses do zoom and focus "backwards" (like Nikon) while Sigma lenses zoom and focus in the right (Canon) direction.;-)
    – Michael C
    Feb 20, 2016 at 1:43
  • Of course with the changes over the last couple of years in the dollar/yen exchange rate the Canon 17-55 can now be had for around $880 from authorised sellers or a little over $700 off e-Bay or at the Canon refurb store. That's a bit less than the $1,100-1,200 it used to run.
    – Michael C
    Feb 20, 2016 at 1:50

When trying to maximize bokeh you want to move the subject closer to you and farther away from the background. If the subject is halfway between you and the background (assuming something simple, like a wall and not the scene in your example) and then you move the subject towards you, but then you also move yourself so that your subject is still halfway then you won't see much difference.

This is one reason to get low when photographing animals and children. If you shoot down the background (the immediate ground) is relatively close, but if you get low the background becomes something distant and makes for better bokeh.


You need a much faster (smaller F number) lens. The Canon 50mm F1.8 is very inexpensive and will do a far better job. The Canon 50mm F1.4 is still less than $500 and has what you are looking for. The good news is that while a 50mm is traditionally considered too short for portraits on a full frame camera, with the 1.6 crop factor, a 50mm works well on an APS-C camera.

I rented a Canon EFS 17-55 F2.8 for a wedding and loved it. So much so that I bought one, and now its the lens I use at least 80% of the time.

  • 1
    50mm is not too short for portraits. It's actually the sweet spot for many photographers using full frame bodies. 35, 50 and 85mm lenses for portraits will produce different perspectives and can be used for different purposes. Oct 15, 2013 at 10:34
  • P.S. I owned a EF-S 17-55mm for two years until I bought a 5D Mark III. One of the best EF-S zooms out there. Oct 15, 2013 at 10:38

When trying to achieve a blurred background for a given subject size, and framing, three effects are important:

  1. Maximise your aperture (meaning the lowest number)
  2. Maximise your focal length (because of the compression the background will appear more blurred)
  3. Maximise the distance between the subject and the background

Here you can see a comparison between the long and short end of your lens, and the 50mm f1.8 which is the cheapest option to improve in this area. This graph applies to taking head and shoulder portraits:

Lens comparison


As you can see the long end of your lens can provide substantially more background blur then the short end, but the 50mm easily a lot more.


You should be shooting at f3.5 and not 5.6. The larger the aperture, the shorter the DOF, which is what you are going for. If you cant get it the way you want it at 3.5, you need a lens that goes down to a larger aperture like F1.8 to make it the bokeh more apparent.

  • Max aperture is f5.6 at the tele (135mm) end.
    – BBking
    Oct 14, 2013 at 6:41
  • Well then he definitely needs a new lens then if he is trying to shot it at the 135mm and get the DOF. Why not move the camera closer to get the same point of view and minimum zoom so you can try f3.5 and see if you get enough bokeh.
    – Swami
    Oct 14, 2013 at 13:17
  • Depending on the minimum focusing distance at 135mm, narrow DoF is still achievable, even at f5.6.
    – BBking
    Oct 14, 2013 at 22:16
  • Depending on the minimum focusing distance and the size of the subject, then. If you're taking a portrait of a person with a 135 mm lens close enough to get an out-of-focus background at f/5.6, that's going to be quite a close-up. Oct 15, 2013 at 19:05

I'm not a Canon shooter, so I'm not very familiar with their lenses, but in my own experience I've found that using a macro lens for portraits really helps me induce very pleasing bokeh into the photo without breaking the bank. Of course, I bought a third-party macro, the Tokina AX-Pro 100m 2.8. They may make it for Canon as well (I have the Nikon version). While they advertise it as an f/2.8 lens, the aperture is not constant as it shifts as the lens extends for focusing but the depth of field is much more shallow with that lens than with any other at same depth of field due to the characteristics of macro photography.

  • Sorry, but this is pretty much wrong. Assuming the same camera and the same subject distance, a macro lens will have exactly the same depth of field at f/2.8 (or any other aperture) as a non-macro lens.
    – Philip Kendall
    Oct 14, 2013 at 14:09
  • I may not know all the technical reasons behind it, but my experience has had me yield far shallower DOF with my macro lens than my other lenses. I also referred to photo.stackexchange.com/questions/14009/… before answering, but I may have misunderstood the information there.
    – A.Rdz
    Oct 14, 2013 at 15:07
  • 3
    The crucial point there is the first line of the accepted answer: "Depth of field decreases rapidly as you focus closer" (my emphasis). At the same subject distance, a macro lens at f/2.8 will have the same depth of field as a non-macro lens - just a macro lens can focus much closer, at which point you do get a very shallow DoF.
    – Philip Kendall
    Oct 14, 2013 at 15:10
  • And just to clear things up, your lens does have a constant aperture. What you're seeing in the f-stop indicator is automatic bellows compensation. If the aperture number doesn't change with a macro lens, either the lens doesn't know how to talk to the camera, or it's an internal focus lens that's actually shortening its focal length considerably as you focus closer. So at 1:1 magnification you either have a 100mm lens with a compensated aperture of f/5.6, a 65mm-ish lens with a compensated aperture of f/2.8, or somewhere in between.
    – user28116
    Aug 14, 2014 at 9:10

Enough bokeh? Yes, especially for photographs such as that pictured. Groups tend to require a moderate depth of field so as to make all subjects in focus. The picture in your question is quite good with the deeper depth of field it has.

Great bokeh? Not really, as the depth of field is not only equivalent to f5.6 - f9 on your crop body (assuming 1.6x crop factor) at the same focus distance, but the lens construction itself also dictates the quality of the bokeh. More aperture blades as well as the shape of the blades change the characteristics and aesthetics of the bokeh. The quality of the lens elements and coatings also affect the image as a whole.

Once you get an f2.8 zoom or wide aperture prime, you will not only have a shallower depth of field, but will also benefit from a consistent exposure across the zoom range.

Having to change your shutter speed or ISO after zooming can be problematic and a pain in the butt. Wide, constant aperture zoom lenses tend to have better construction and optical quality given their overall cost increases.

For portraits, a great yet relatively inexpensive lens is the Canon EF 50mm F1.4 USM, as well as the 35mm F2 and 85mm F1.8. These all clock in at about $300-400 each as are great for shallow bokeh, especially on full frame bodies.

  • I like how you differentiate on what is enough for group settings, I never really heard/though of that
    – user6189
    Oct 15, 2013 at 4:43

The key is to get as close as your camera will focus. This is the same method if you are zoomed in (likely 3-4 feet focus) or if you are zoomed out all the way (likely 1-3 inches). Obviously the zoomed out 3 inch distance will only work for macro shots. For people and scenery zoom in all the way and get as close as your camera will focus. This works well for a picture of one person but you will not get a group of people.


if your lens 18–135 f/3.5–5.6

Get very close to your model, the closer the better. Keep your model and background as separate as possible by maximizing the background distance. Use your longest focal length (i.e., 135mm) and your widest aperture (i.e. f/5.6). This will produce the most pronounced bokeh your lens and camera will be able to achieve.

I have used a 55–200 VR; at 200mm f/5.6, it creates very good bokeh for head shots.

I have also used a Nikon E-series AI-S 75–150mm f/3.5. At 150 mm, it creates perfect bokeh, the same as my 85mm f/1.8G.

For better results I'm going to buy a 300mm f/2.8. Also, a 200–500mm f/5.6 will give excellent bokeh if you can get close to the subject with a 500mm focal length.

A 20mm f/1.8 will not give better bokeh than 200mm f/5.6. The main idea is to get as close as you can to the subject.


Things that affect Bokeh:

  • Size of the sensor
  • Distance between you and the subject.
  • Distance between the subject and the background.
  • Aperture of the lens (wider the better)

As you will have noticed, good lenses with the widest apertures can get quite expensive (especially zoom lenses eg. 70-200 f/2.8).

What you can do as a cheap alternative that could work for you depending on your shooting style and whether your subjects will remain still (as they are in the supplied photo above), is to buy a good condition Helios 135mm f/2.8 M42 lens from ebay for around £30 (plus £15-£20 for a standard M42 to Canon adapter).

It is an old(ish) metal lens built like a tank that is actually really decent considering its price of £30 pounds.

The reason I say about your subjects remaining still is that it's not a zoom lens and it is manual focus only as you are using it on your Canon with an adapter, but it can be very sharp and is very cheap - I have one and I love it.

If you separate your subjects from the background as far as you can and then try with the 135mm f/2.8 with the aperture set to f2.8 I'd be surprised if you didn't get some nice Bokeh.

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