Howdy, Stranger!

If you're just starting out in the world of photography and want to learn how to get the most out of your camera, then this forum is your new secret hangout spot!

Take better photos today with my Canon T3i Cheat SheetsCheck 'em out!

When to use 18-55mm, 75-300mm and 50mm f/1.8

edited November 2013 Posted in » Canon T3i Forum
Hello Moose, :-)

I own the 18-55mm and 75-300mm lenses, and today I bought the 50mm f/1.8 based on your recommendation. Currently I'm playing/tinkering with them.

Would you mind giving general insights and guidelines on the following, please?

1. When is the best time (type of shots, subjects and scenes) to use 18-55mm, 75-300mm and 50mm f/1.8?
- I am using your link for 50mm f/1.8 as reference, but I'm still a bit confused on which lens to use on a given subject and scenes.

2. What are the typical (can't go wrong) Av, Tv, P, creative settings applicable for common subjects and scenes (at night with no light, sports, babies, food, scenery, etc) for each of these lenses?
- will the T2i cheat sheet be able to guide me with these settings?

Thanks so much for the guidance.



  • edited November 2013
    Hi Shutterfly,
    I would like to give you some clearcut answers but, in photography nothing is ever clearcut.

    1) 50mm f/1.8 comes into its own indoors in low light. That's not to say that it can't be used outdoors. However, 50mm is not classed as wide angle so shooting indoors can be quite restrictive unless you have big rooms which enable you to back off as well as approach your subject. In this respect the 18mm end of your 18-55mm is a better option.

    2) The 18-55mm is a general purpose zoom which will enable you to photograph everyday subjects and also landscapes with the 18mm end. Like the 50mm you need to remember that you have feet that can walk towards or away from the subject as the zoom ratio is small.

    3) The 75-300mm is most commonly used for shooting sports and wildlife. However, it can also be used for landscapes, candid photography and portraits. Most photographers use something like an 85mm for portraits and so this is possible within the range of your 75mm-300mm.

    Having said all that, you can use the lenses whichever subject you choose; you just have to approach the subjects in slightly different ways.

    It must be remembered also that the T3i has a 1.6 crop factor. This doesn't make your lenses magically more powerful, it simply means that your picture is cropped by a factor of 1.6 to give you the same result as on a full-frame camera, but you still need to be aware of the effect on your lenses.

    So your 50mm is the same as mounting an 80mm on a full frame camera. The 18-55mm is the same as 29-88mm and the 75-300mm is the same as 120-480mm.

    In the real world, I try to discourage people from thinking of the above numbers and concentrate on understanding the lenses they have.

    One of the best ways to do this is to set up your camera shooting one particular subject, preferably non-moving. Start with the 18-55mm and take pictures throughout the zoom range. Then swap out to the 75-300mm and do the same again.

    If you have the facility, print out 6x4's or 7x5's of all your shots and lay them out in front of you. By studying them, you will soon be able to decide which lens and/or zoom factor was right for that shot.

    A little time spent like this can be very valuable in helping you decide which lens you should be using for a particular shot.

    As for the second part of your question, yes Moose's cheat sheets will be a great resource for you.

    Best regards, PBked
  • edited November 2013
    Hello PBked,

    These are very insightful explanations and guidance for me as a beginner. I appreciate your generosity in sharing your knowledge. Thank you!

  • Hey @shutterfly - I kindly thank and appreciate @PBked's wonderful advice...I agree with everything he said. Here are some additional thoughts...

    1. I tend to start most of my photo adventures with a prime lens. I just compose a scene/subject with my feet and shoot away. When I'm presented with something that I can't quite capture with a prime lens, I'll switch to a wider lens or a longer lens.

    2. As for settings, a good rule of thumb is to use Aperture priority (Av) for things that are motionless or have very little movement and use Shutter priority (Tv) for things that move quickly.

    Aperture priority allows you to control the depth of field...low f-numbers to isolate your subject against a blurry background and higher f-numbers to put more of the scene into focus.

    Shutter priority allows you to control shutter speeds to freeze movement and slow shutter speeds to capture movement.

    3. As for my cheat cards, I'm finishing up a set for the T3i this week. Should be out next week. Initially this set will be for the T3i and 18-55mm combo, but shortly following I'll be releasing one for the 50mm f/1.8 as well which will have a different assortment of shooting scenarios.

    All the best!
    - Moose
  • edited June 2014
    I'm new to the SLR world and I'm getting to know my Rebel T3i. This forum has been really really helpful and I'm buying the cheat sheets. Also just downloaded the free trial of adobe lightroom. Thanks for the tips. Good advice to start with one type of scene and practice with both lenses.
  • edited July 2014
    Hi! I'm a newbie and the cheat cards are really helpful. I have the 18-55mm and 75-300mm lenses. Unfortunately I don't have a built in stabilizer. My concern is if that's the reason for the "blurred" images using the cheat settings? Unfortunately it has been raining for a few days and my daughter is going to be a flower girl in a wedding this weekend. I would really love to get some tips to get a few great shots of her. The ceremony is at 3pm and reception to follow. It is a church wedding and restaurant venue afterwards. Thanks in advance. :)
  • edited July 2014
    Several things can cause blur.

    1. Focus blur. If something is out of focus, it’s blurry. Easy. Solution is to just nail your focus.

    2. Subject motion blur. This happens when your subject is moving and your shutter speed is too slow to freeze the action. Solution is to use a fast shutter speed. Experiment with what speed you need for various situations. The faster your subject moves, the faster shutter speed is required to freeze the action. If people are walking slowly, something like 1/100 should be fine. If they pick up the pace a bit, then perhaps 1/250. If they run, then 1/500 (maybe faster). For sports where there’s erratic and quick movements, then 1/1000.

    3. Camera movement blur. This happens when you’re hand-holding your camera and use a shutter speed that’s too slow to compensate for the vibrations that you introduce to the camera.
    Image stabilization is only effective against this type of blur. So if you don’t have image stabilization, the general rule is to use a shutter speed that is the reciprocal of your effective focal length. That is, you take your focal length, multiply it by your crop factor, and take the reciprocal of that number. So if you’re shooting at 300mm, use 1/450 sec. If you’re shooting at 50mm, use 1/80 sec.

    If you read through this, you may think that the solution is as simple as nailing your focus and using a really fast shutter speed like 1/4000 sec. Yes, you must nail your focus. That’s important. But for shutter speed, you must keep in mind that using a faster shutter speed means you’re reducing the amount of light entering your sensor. So you must either open up your aperture and/or boost your ISO to compensate.

    If you’re in daylight, this isn’t an issue, but if you’re indoors or if the sun has set, you’ll find that your lenses are not designed for low-light use since their maximum aperture is not very large so you’re limited to boosting your ISO to very high levels just to maintain barely acceptable shutter speeds.
  • This is really useful, also you may be interested in equipment sets for such types of photo sessions
Sign In or Register to comment.