Need advice on a lens with good depth of field

LizzyBennet

Im buying a Canon 70D to use for videos (Youtube) and would like t buy a lens that will give me debt of field but that i wont have to use to far away from me, i HAVE THE canon 50mm 1.8 but the camera has to be to far away from me when filming to get a good debt of field. Any suggestions on a lens that isn't crazy expensive ?

magicbastarder

LizzyBennet wrote: »

Im buying a Canon 70D to use for videos (Youtube) and would like t buy a lens that will give me debt of field but that i wont have to use to far away from me, i HAVE THE canon 50mm 1.8 but the camera has to be to far away from me when filming to get a good debt of field. Any suggestions on a lens that isn't crazy expensive ?

You mean you need a telephoto lens I think? Depth of field is primarily about the aperture you have chosen.

flyingsnail

I think you might be confusing depth of field and field of view. Depth of field is how much of an scene is in focus and field of view is how much of a scene you can see.

I think what you are asking is what lens to get so you can be closer to the camera and still have all of you in the shot as the 50mm (85mm equivalent on your camera) is forcing you to be too far away from the camera.

Pete67

You probably know this already, but just in case - depth of field refers to how much of the scene in front of the camera is in focus, a large depth of field means that pretty much everything from a foot or two from the camera all the way to objects in the far distance are sharp. A very narrow depth of field means that only objects at a particular distance are sharp, and everything else is blurred - often used deliberately to blur the background in order to make the subject standout more.

Field of view on the other hand refers to the angle of view that the camera sees - both left to right and top to bottom. A wide angle lens will see a lot more than a telephoto lens. Your 50mm lens is mildly telephoto on a crop sensor body such as the 70D. A wide angle lens on a 70D could be anywhere from 10mm up to 24mm or so. If you are looking for greater field of view, or need to include more in the scene with moving the camera further away, then a wide angle lens is what you need.

If you are happy with the field of view, and want more of the scene to be in focus, then you have a couple of options to control depth of field - the first is aperture, your 50mm lens will give you huge depth of field at f22, and very little at f1.8. However if you are shooting with very small aperture such as f16 or f22, you need either a lot of light, or a high ISO setting to make the camera more sensitive to the available light. High ISO settings increase noise so you may end up with grainy images, so as with most things it's a compromise. You need to experiment a lot to see what works best in various shooting situations.

The second is focal length; generally, a wide angle lens will give you greater depth of field at a given aperture, when compared to a standard lens, while also allowing you to position the camera closer to the subject.

A few options to get you started, the zoom lenses will give you greater flexibility, but cost a bit more.

Canon EF-S 24mm f2.8

Tamron 17 to 50 f2.8 zoom

Sigma 17-50 zoom f2.8

LizzyBennet

Im looking to buy a Canon 70d new, for a reasonable price. I was going with Hdew cameras but they will only except Bank Transfer and I need to put it on my credit card. can anyone recommend anywhere thats is a reputable website ? It was working out just over €800 on Hdew Cameras for the body and kit lens

CabanSail

I am a bit confused as to what is a 'good depth of field'? Is it a wide or shallow DoF that you are seeking?

killym

I think she wasnt to be verything in focus while filming, either way it can't be done unless she understands a few principles...

ED E

If she's using the 50 on a crop its acting like an 80mm so to get a good FoV she would have to be a good couple meters back from the camera. If this is for VLOG style video, especially a permanent setup then thats awkward.


LizzyBennet if this sounds right, that you just need to have the camera closer and "get everything in" then get something like a 35mm or maybe even a 22m. The YN35 is a nice chinese clone lens for Canon that will be very good for video if you arent shooting moving subjects.

LizzyBennet

ED E wrote: »

If she's using the 50 on a crop its acting like an 80mm so to get a good FoV she would have to be a good couple meters back from the camera. If this is for VLOG style video, especially a permanent setup then thats awkward.


LizzyBennet if this sounds right, that you just need to have the camera closer and "get everything in" then get something like a 35mm or maybe even a 22m. The YN35 is a nice chinese clone lens for Canon that will be very good for video if you arent shooting moving subjects.

is there anywhere online you would recommend to buy ? Thanks

photo_net

If they don't want your money, you could get it online using a credit card - check out amazon.co.uk. I would be slightly more cautious buying a lens online incase it gets damaged en route, but a camera body will definitely be fine (I've bought loads of electronics etc. online before).

ED E

Amazon stock them, 70 odd GBP from the manufacturer.

Before you go ahead and buy though make sure its enough, grab a kit lens and set it to 35mm, that'll give you an idea of what it'll be like.

killym

ED E wrote: »

Before you go ahead and buy though make sure its enough, grab a kit lens and set it to 35mm, that'll give you an idea of what it'll be like.

Totally agree, before You buy it,make sure it's this thing You want, otherwise You might end up with similar questions.

LizzyBennet

Im obviously not very familiar with Dslr lenses what i basically want is to be able to have the camera a couple of feet in front of me for filming and have a blurry background behind me, with me being in focus and the 50mm 1.8 I have is absolute crap for that because it has to be so far away from me to get a nice blurry background and i find its to zoomed in on me i want some background. My kit lens 18 - 55mm works nicely but without the blurry background

Heebie

A 50mm lens shouldn't have to be far away from you to focus. Generally you should be able to focus on things more than a foot or two away from the end of the lens with a good 50mm. If it's an f 1.8 50mm, that's not bad, and if you set the aperture correctly, it should definitely do what you want.
With an f1.8, you should be able to have your nose in-focus, and everything else blurry, or have everything in the image in focus, and anything in-between. (with an f.14 you could have just the TIP of your nose in focus)
Setting the aperture around 4 to 5.6 will probably give you the blurred-out-background you're looking for as long as the background isn't right behind you.
The lower you set the aperture (actually, technically it's the LARGER you set the aperture.. lower number means bigger aperture) the less of the image will be in-focus.
So, try setting it to around 4, then focus on yourself. If you move a lot, you'll move in and out of focus if using a shallow depth-of-field, so you might want to have a background quite a ways behind you, and use a wider DoF (higher number) so you don't drift in and out of focus.
You don't want the camera to be automatically setting the aperture in this instance, either. You'll want to set that manually.
You'll probably want to experiment to get the right results.
Your 18-55mm kit lens should be able to do this as well, as long as you manually set the aperture low enough, but a "nifty fifty" is a faster lens. Your 18-55 might not go below f4 or 3.5, and if you're close to it, or your background is close to you, that won't work.

http://www.exposureguide.com/focusing-basics.htm

This seems to explain it reasonably, and has a potentially useful diagram.

LizzyBennet

Thank you that was all really helpful

killym

LizzyBennet wrote: »

50mm 1.8 I have is absolute crap for that

I get Your idea now,You want to frame Yourself in camera and have a blurry background. Well something wide and at fast aperture, let's say sigma 20mm f1.4, now You can check the price

ED E

Heebie wrote: »

A 50mm lens shouldn't have to be far away from you to focus.

Correct, but not on a crop sensor. Its 80mm effective.


35 prime sounds good IMO, the kit lens has pretty weak bokeh comparatively.

Pat Dunne

http://www.boards.ie/vbulletin/showthread.php?t=2057154505