2.8 vs 4.5

[RumDaddy]

The question I got is. How much more DOF control does a 2.8 lens give you over a 4.5.


Im looking to upgrade from a 50D to a 5D mark II. Im also looking into upgrading my lenses. Cuz Im pretty sure 50D lenses are designed for 1/2 sensor cameras and a 5d is a full sensor camera. But to make matters more expensive. :er: Im almost certain I need some fast glass. "2.8" glass. The reason Im looking into 2.8 is because Id like more control over blurring out the background. Im really into DOF shots. I know... Who isnt. Ill tell ya who isnt the photographer who spends $300 on a 4.5 lens compared to the photographer who spends well over 2.8 times as much money on a 2.8 lens. PLEEZ correct me if Im wrong and I hope I am, cuz those 2.8 lenses are CRAZY EXPENSIVE!!

 

[RockstarPhotography]

Its not so much the dof photographers are after when they buy 2.8 lenses. Its the ability to shoot in low light situations.

 

[480sparky]

An f/2.8 lens will give you the same DOF as an f/4.5 lens if it's set to f/4.5. The difference will be how bright the viewfinder appears.

 

[RumDaddy]

Not positive but I believe thats where the term fast glass comes from. Those lenses are known for working quicker and and also capturing brighter images in low light situations.

I NEED BETTER CONTROL OVER THE DOF. Im using a 50D and I have a Canon EF 28-135mm f/3.5-5.6 IS Image Stabilizer USM Autofocus Lens. I have very little DOF control. Any suggestions. I also have a 70-300 mm lens. so I can back up real far and zoom in. But I think thats not the most desired or professional way of controling the DOF. As a matter of fact. Im a ambarrased I brought it up. LOL!

 

[Einstein]

the most cost effective solution would be to get a walk around lens in the less expensive f4 region (see the canon 17-40mm f4L and 70-200 f4L) and then get a prime lens or two that will allow you to play with DOF. No lens will let you 'control' the DOF like a prime and they are relatively cheap. Look at the 50mm 1.4 and 1.8. I have the 1.4 and it's awesome in so many ways.

 

[Stradawhovious]

DOF can be manipulated in many ways. The three most common are aperture, distance from subject and focal length.

If your subject is at a set distance, you will have a shallower DOF at a larger aperture than smaller.

50mm f/1.8


50mm f/8


If your lens is set to a constant aperture and focal length, you will have a shallower DOF if you are closer to the subject than if further away,

50mm f/5.6 close


50mm f/5.6 further away





you will have a shallower DOF with a longer focal length than a wider one.

180mm f/5.6


50mm f/5.6 same distance,



Hope this helps. Please forgive the mundane subject, and terrible photos, it was a quick and dirty visual aide.

 

[kundalini]

2.8 vs 4.5

The difference is 1-1/3 stop.

 

[invisible]

Im looking to upgrade from a 50D to a 5D mark II.

Full-frame cameras produce the impression of a shallower depth of field. (Please see Nathan Gardner's reply here for more on this.)

With your current f/4.5 lens you might be able to produce the impression of a DoF identical to what you'd get with an f/2.8 lens on a cropped-sensor camera. You'll need, however, to make sure that your f/4.5 lens is designed for use on full-frame cameras.

 

[JohnBoy]

The other difference is the optical quality of 2.8 and better lenses. If you have only ever used 3.5 4.0 or 5.6 zooms you will be blown away by the image quality of a 50/55mm f1.8 or f1.4 in any camera system, particularly at a stop below wide open ie f2.8 or f2 - these little primes are the best bargain in lenses even if you have to buy them new.

JohnBoy

 

[KmH]

Not positive but I believe thats where the term fast glass comes from. Those lenses are known for working quicker and and also capturing brighter images in low light situations.

I NEED BETTER CONTROL OVER THE DOF. Im using a 50D and I have a Canon EF 28-135mm f/3.5-5.6 IS Image Stabilizer USM Autofocus Lens. I have very little DOF control. Any suggestions. I also have a 70-300 mm lens. so I can back up real far and zoom in. But I think thats not the most desired or professional way of controling the DOF. As a matter of fact. Im a ambarrased I brought it up. LOL!

Professional photographers usually use longer focal length lenses, like a 70-200 mm zoom at or near 200 mm, to get the DOF they want.

Lens aperture is only one of the 4 things that control DOF. Not considering the other 3 factors is why, " I have very little DOF control."

http://blog.groundupphotos.com/2009/06/26/photography-lesson-3.aspx