Full frame question, pretty basic

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After months of itching, and with an epic holiday on the horizon, I'm pretty much set on getting a 5D classic to replace my 450D.

There is one basic question nagging me and I'm curious to know before the plunge.

I know that depth of field alters dependant on sensor size. So will the 5D give me a narrower or wider depth of field at relative settings? Also, are shutter speeds directly comparable for the same conditions, or is there some difference?

Thanks a bunch for your responses.
 
Firstly - exposure will be the same - it is dependent on light, not sensor size.

Depth of field will be lower for the same subject, same lens, same framing as I understand it because you will be closer to the subject.

Phil
 
philthejuggler said:
Firstly - exposure will be the same - it is dependent on light, not sensor size.

Depth of field will be lower for the same subject, same lens, same framing as I understand it because you will be closer to the subject.

Phil
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Same subject, framed the same (focal length obviously adjusted), from the same position - FF gives less DoF, by a bit over one stop.
 
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Exposure is exposure but other choices come into it and could affect your aperture, shutter speed and ISO settings plus it's more complex than bigger format = less DoF.

You'll possibly be using longer lenses than you would on a smaller sensor and this could possibly make out of focus areas more visible and create a different look to your shots including creating the impression of less DoF.

That might be good news if that's what you want but the other side of the coin is that if you want a shot to look as if it has more DoF you could end up using narrower apertures and that could mean either slower shutter speeds or higher ISO settings or both.

Another possible drawback is that a full frame camera and lenses might be bulkier and heavier than a smaller sensor camera and lens set up.
 
woof woof said:
Exposure is exposure but other choices come into it and could affect your aperture, shutter speed and ISO settings plus it's more complex than bigger format = less DoF.

You'll possibly be using longer lenses than you would on a smaller sensor and this could possibly make out of focus areas more visible and create a different look to your shots including creating the impression of less DoF.

That might be good news if that's what you want but the other side of the coin is that if you want a shot to look as if it has more DoF you could end up using narrower apertures and that could mean either slower shutter speeds or higher ISO settings or both.

Another possible drawback is that a full frame camera and lenses might be bulkier and heavier than a smaller sensor camera and lens set up.
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Alan, that needs to be rephased. The way it reads, you are mixing up field of view with focal length and depth of field.

If the framing is the same (field of view), from the same distance, and aperture is adjusted for format, the depth of field is the same and the 'out of focus area' (bokeh) is also the same. The fact that you have changed focal length to maintain framing makes no difference.
 
FF pictures look nicer than ones from crop sensors. It doesn't matter why, they just do.

So forget all about focal lengths, fields of view and dof tables. That sort of knowledge will never make your photos any better.

Stop obsessing, splash the cash, and go take photos. ;)
 
Ed Sutton said:
FF pictures look nicer than ones from crop sensors. It doesn't matter why, they just do.

So forget all about focal lengths, fields of view and dof tables. That sort of knowledge will never make your photos any better.

Stop obsessing, splash the cash, and go take photos. ;)
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That is an incredibly sweeping and subjective statement. FF cameras do have some qualities, but having owned many FF and crops I honestly cannot see a massive difference. Glass makes much more difference... and intelligent use of light makes MUCH more difference.
 
I think there are a lot of myths and half truths with depth of field when comparing APS-C and full frame. Full frame only makes depth of field shorter on a 50mm lens as the field of view is 50mm, on a crop it will be 75-80mm. If you put a 50mm equivelent lens on a APS-C sensor and shoot it at the same F-stop (say F2.0) you will get the same depth of field.

Image quality can be improved by going full frame, but as said previously image quality can be improved with glass and improving lighting conditions (or shooting in the right lighting conditions).

I've only used a 5D classic once and TBH I didnt notice much difference in IQ compared to my 5D at low ISO. At higher ISO there was a noticable IQ difference as the noise within the RAW files was much lower from ISO800.
 
The23rdman said:
intelligent use of light makes MUCH more difference.
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I agree with that :thumbs:

I do find that my D700 has a slightly improved dynamic range than the D300, and does produce much cleaner images at higher ISO settings, but I have no qualms using the cropped sensor body if it is the better tool for the job.
 
DaveKing said:
I think there are a lot of myths and half truths with depth of field when comparing APS-C and full frame. Full frame only makes depth of field shorter on a 50mm lens as the field of view is 50mm, on a crop it will be 75-80mm. If you put a 50mm equivelent lens on a APS-C sensor and shoot it at the same F-stop (say F2.0) you will get the same depth of field.

Image quality can be improved by going full frame, but as said previously image quality can be improved with glass and improving lighting conditions (or shooting in the right lighting conditions).

I've only used a 5D classic once and TBH I didnt notice much difference in IQ compared to my 5D at low ISO. At higher ISO there was a noticable IQ difference as the noise within the RAW files was much lower from ISO800.
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Yes, and that doesn't help.

If you take the same picture, framed the same*, from the same position, the depth of field at a given f/number will be less on full frame. The calculation to make it the same is f/number x crop factor, so f/5 on a Canon 1.6x cropper will be equal DoF to f/8 on FF - difference of just over one stop.

* For the same framing, focal length must be adjusted by crop factor, eg 50mm lens changed to 80mm.
 
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