how do i get aperture right with a canon 5d mark 11 and canon 70 - 200 mm is lens?

Question

i have recently bought the 5d mark 2 and canon 70 - 200 mm is lens but i cannot seem to get the aperture correct weather i use a large or small f stop i cannot seem to get the depth of field rite the back ground looks the same in both photos irrespective of weather ive used the large or small f stop i cannot get the back ground to blur or sharpen if i wish to .the back ground stays the same no matter what size of aperture i use
any help is greatly appreciated any tips also LOL
kind regards
matt

Answer 1

Hi Matt.



It's not the gear.



I am going to assume you want to really blur the background, as you will struggle to get massive depth of field with a 200 lens.



You have to think about focal length: the longer the lens the more shallow the depth of field no matter at f2.8 or f22.



You also need to think about perspective, i.e. the distance between the camera & the subject and then the subject and the back ground.



The closer the subject to the camera, the more out of focus the background will be.



Most folk assume the ratio that the distance between the subject and the background should be at least double the distance between the subject and the camera.



As a guide, set your lens to f2.8. Set your focal length to 100mm.



Place your subject so they are against a distant expansive background (cityscape, landscape) zoom with your feet.



With the camera in portrait orientation move back from the subject until they are shoulder width filling the frame with the eyeline 2/3 up the frame.



Take your shot.



You should get sharp subject and soft background.



You can accentuate this by zooming to 200mm and moving back further to keep the composition, although this will 'flatten' your subject.



With the best will in the world mate, you have the gear, you need a class to get the skill. No offence.

Answer 2

I'm assuming you are at least shooting in "Av" or Aperture Priority mode or "P" Programmed Exposure mode, right? Also, which 70-200mm IS lens are you shooting? There's an f/2.8 and an f/4 version. The larger, heavier and more expensive f/2.8 lenses allow the most shallow depth of field as they have a wider aperture. Also, what's the distance to your subject? I only ask because depending on that distance, you may have stumbled across the hyperfocal distance of your lens which means everything from point "x" to infinity will appear to be in focus or reasonably close to it.



If none of the stuff I've mentioned makes sense, at the very least, I would suggest checking out the "Digital Photographer's Handbook" by Tom Ang because these are basic concepts you should know. The 5D Mark II and the EF 70-200mm L-Series lenses are top notch equipment. But they will still generate crappy pictures if you don't know how to use them to their potential.

Answer 3

I would suggest getting the book "Understanding Exposure" by Bryan Peterson. This book will explain the relationships of Aperture, Shutter speed and ISO and their effects on creative photography.



In short. the larger the aperture the smaller the f stop number f/2.8 is the largest. and will give you the blur that you are looking for as will other focal lengths with lower number, as you get into the higher numbers you will find less of a blur, until you find your photo sharp front to back.



Try setting your camera on a tripod. and focus on an object about 5 feet away.. til it nearly fills the frame.. using AV mode and starting with f/2.8 take a shot.. change to the next f stop and take another shot until you reach f/22 .. then look at the series of photos and see how the DOF changes in each photo.

Answer 4

ah the joys of a lack of experience,



at short focal lengths, ie 70mm, the DOF is less apparent than it is on a longer lens, say, 135mm.



the easiest way is to use macro, (upto 2m) or set F1.8... however, its easier to photoshop it, than buy another lens...



using the cam on auto wont help, check the default settings



and just try it, shooting and checking... but, the old principle, of stand back and zoom in still works, but you have to remember, although the lenses and cameras look the same, they dont behave the same way as 35mm, the optics are different..



i use olympus cameras, and the difference between F1.8, and F22 on a short lens, 14mm is almost imperceptible untill you enlarge it. yet, with a 135mm lens, i get all the seperation i need...



read about DOF calculations with digital lenses... but, the closer you are, the greater the effect... (only on longer focal lenses.)



which is why the press snappers use hideously expensive glass... them huge white lenses, 300mm, and F2... (its normally about F8) thats how they get a limited DOF... and most of us havent got 5 thousand pounds...



thankfully, the rest of us have photoshop, painstshop pro x2, even has an appplet to recreate DOF...

Answer 5

with the aid of fact that's for Sigma DSLRs, it certainly won't paintings on a Canon. Or do you doubt that it may fairly be for a Sigma digicam? Sigma does certainly make DSLRs, albeit that's between the extra obscure manufacturers for digicam bodies, and thesea use a distinctive lens mount than the different manufacturers. Too undesirable - $one hundred twenty five for a 70-2 hundred/2.8 is a scouse borrow.

Answer 6

This site contains photography tutorials and courses for you to study at your own pace. https://tr.im/8mLZA



To get started, all you need is a camera, whether it be the latest digital camera or a traditional film-based apparatus!



Read about what is ISO, aperture and exposure. Discover different types of lenses and flash techniques. Explore portrait photography, black and white photography, HDR photography, wedding photography and more.

Answer 7

Depth of Field (DOF) is a product of three factors:



1) The focal length of the lens.

2) The f-stop chosen.

3) Subject distance.



At http://www.dofmaster.com/dofjs.html you can learn about DOF and use the handy DOF Calculator to compute DOF for any combination of lens focal length, f-stop and subject distance imaginable.



Since you failed to tell us which 70-200mm lens you have - f2.8 or f4 - I'll guess its the f4 version. Here are some examples from the DOF Calculator.



70mm @ f4 focused to 10' DOF is from 9'-4'' to 10'-9''. Anything from 0'-8'' in front of your subject to 0'-9'' behind it will be in focus.



70mm @ f16 focused to 10' DOF is from 7'-9'' to 14'-1''. Anything from 2'-3'' in front of your subject to 4'-1'' behind it will be in focus.



70mm @ f32 focused to 10' DOF is from 6'-4'' to 24'-0''. Anything from 3'-8'' in front of your subject to 14'-0'' behind it will be in focus.



200mm @ f4 focused to 10' DOF is from 9'-11'' to 10'-1''.



200mm @ f16 focused to 10' DOF is from 9'-8'' to 10'-5''.



200mm @ f32 focused to 10' DOF is from 9'-4'' to 10'-8''.



Calculations based on your camera.



If your lens is the f2.8 version there really isn't a great deal of difference in the DOF between f2.8 and f4 although at f2.8 the DOF is shallower but only at 70mm. At 200mm the DOF (at f2.8 or f4) is all but identical.



You can achieve some impressive DOF with the 70mm end at f32 though.



70mm @ f32 focused to 100' DOF is from 14'-5'' to infinity. Anything from 85'-7'' in front of your subject to as far as you can see - infinity - will be in focus.