Login or Join Now

Upload your photos, chat, win prizes and much more

Username:
Password:
Remember Me

Can't Access your Account?

New to ePHOTOzine? Join ePHOTOzine for free!

Like 0

Canon 40d or 5d mk1

Join Now

Join ePHOTOzine, the friendliest photography community.

Upload photos, chat with photographers, win prizes and much more for free!

GlennH
GlennH  91918 forum posts France1 Constructive Critique Points
28 Feb 2013 - 5:29 PM

In a real-world scenario the subject distance is likely to vary, since most of us frame up a picture according to content and not feet and inches. That's when the DOF in a full-frame camera becomes effectively shallower.

Sponsored Links
Sponsored Links 
28 Feb 2013 - 5:29 PM

Join ePHOTOzine for free and remove these adverts.

Paul Morgan
Paul Morgan e2 Member 1315365 forum postsPaul Morgan vcard England6 Constructive Critique Points
28 Feb 2013 - 5:32 PM

Yes but your avoiding the facts.

Most people go on about M4/3 not giving you as much shallow dof, it will and it will give you tighter control using the same lens.

But most people will compare say a 25mm M4/3 lens against say a 50mm lens on full frame, and of course doing this the dof with a M4/3 lens will be greater and for obvious reasons.

Last Modified By Paul Morgan at 28 Feb 2013 - 5:36 PM
SteveHunter
28 Feb 2013 - 5:47 PM

If you used a 50mm lens on both a Full Frame camera and a crop sensor with the same aperture taking a photo of the same object from the same distance, say a 5D and a 50D, then exactly the same things would be in focus exactly the same amount on both cameras.

The difference would be the cropped camera would only have stored the central part of the image as it's sensor is smaller and would have missed the bits round the edge that the Full Frame sensor would have captured.

If in a real world scenario you wanted to take the same photo of the same object with the same aperture from the same place with both cameras you would need to use different focal length lenses. You would keep the 50mm lens on the cropped camera, but need an 80mm lens on the Full Frame camera.

Now there is a difference in the Depth of Field produced by both cameras caused by the fact that in order to get the same photo on the Full Frame camera you have had to use a longer lens, the longer lens reduces the Depth of Field so less of the shot will be in focus.

Big Bri
Big Bri  1315586 forum posts United Kingdom
28 Feb 2013 - 5:53 PM

Right. If you take that into account, the DOF on the smaller sensor will be very slightly larger.

Paul Morgan
Paul Morgan e2 Member 1315365 forum postsPaul Morgan vcard England6 Constructive Critique Points
28 Feb 2013 - 5:58 PM

What will be very slightly larger ?

From that check I did the full frame camera with a 50mm had a depth of field that was more or less doubled, hardly slight.

GlennH
GlennH  91918 forum posts France1 Constructive Critique Points
28 Feb 2013 - 6:05 PM

The most radical effect on DOF is caused by subject distance, not lens focal length; the real-world effect of any crop factor is that you're always likely to be further away from the subject for any given composition. In switching between a 40D and 5D with an existing set of lenses, that might be pertinent.

Paul Morgan
Paul Morgan e2 Member 1315365 forum postsPaul Morgan vcard England6 Constructive Critique Points
28 Feb 2013 - 6:12 PM


Quote: The most radical effect on DOF is caused by subject distance, not lens focal length

Yes your right, but people get there facts mixed up and assume dof is greater using a crop sensor, when using the same lens and at the same distance.

This is a good example, B&W pictures at the bottom.

http://betterfamilyphotos.blogspot.co.uk/2013/01/olympus-om-d-first-impressions-...

Last Modified By Paul Morgan at 28 Feb 2013 - 6:14 PM
Big Bri
Big Bri  1315586 forum posts United Kingdom
28 Feb 2013 - 6:35 PM


Quote: Yes your right, but people get there facts mixed up and assume dof is greater using a crop sensor, when using the same lens and at the same distance.

Nobody's disputing that. But if you used a 100mm lens on a 5D for the same field of view, you would need a 62.5mm lens on a 40D. That would give you slighter higher DOF than 100mm on the 5D.

Big Bri
Big Bri  1315586 forum posts United Kingdom
28 Feb 2013 - 6:36 PM

And the link you linked to proves it perfectly.

Big Bri
Big Bri  1315586 forum posts United Kingdom
28 Feb 2013 - 6:36 PM

The Leica 25mm clearly has more DOF than the 5D at 50mm.

Big Bri
Big Bri  1315586 forum posts United Kingdom
28 Feb 2013 - 6:37 PM


Quote: The FF picture @ f/1.4 displays crazy thin DOF, not possible at all with m4/3

Paul Morgan
Paul Morgan e2 Member 1315365 forum postsPaul Morgan vcard England6 Constructive Critique Points
28 Feb 2013 - 7:12 PM


Quote: And the link you linked to proves it perfectly

Yes it does Smile


Quote: The FF picture @ f/1.4 displays crazy thin DOF, not possible at all with m4/3

Not good at all is it, much more control using a 25mm at F1.4, crops give you more dof control in low light Smile

Big Bri
Big Bri  1315586 forum posts United Kingdom
28 Feb 2013 - 7:14 PM

No, it gives you more DOF. Less control, as you can't reduce it.

Paul Morgan
Paul Morgan e2 Member 1315365 forum postsPaul Morgan vcard England6 Constructive Critique Points
28 Feb 2013 - 7:18 PM

Might be good if you wanted to isolate a street sign against a busy background, but that full frame dof is pretty useless for a portrait in low light unless you raise the ISO to use a smaller aperture, more dof is more control Smile Smile

Crop DSLR`s have there advantages.

Stick with the 40D

Last Modified By Paul Morgan at 28 Feb 2013 - 7:21 PM
Big Bri
Big Bri  1315586 forum posts United Kingdom
28 Feb 2013 - 7:24 PM

LOL. Nice U turn....

Add a Comment

You must be a member to leave a comment

Username:
Password:
Remember me:
Un-tick this box if you want to login each time you visit.