Does sensor size affect shot composition?

[Stab]

I know that sensor size has an effect of the 'width' of lenses, the so called crop-factor.

I also understand that, in order to get comparible shots, you put wider lenses on for instance a GH2 as opposed to a 5D to get about the same composition.

But is it exactly the same shot? No, because different lenses do have an influence on the how the shot turns out in terms of depth, depth of field, distortion, etc.

Is it possible to make the exact same shots on a GH2 as on a 5D for instance? What are the differences in composition, as a result of sensor size and thus using different lenses?

 

[Amr Rahmy]

the wider or more telephoto the lens is, you would get more of the background or compress the background in a more pleasing way while the subject stays the same.

 

[Barry_Green]

But is it exactly the same shot?

Yes it is.

No, because different lenses do have an influence on the how the shot turns out in terms of depth, depth of field, distortion, etc.

Only if they're really cheap/bad lenses.

If you use the exact same camera position, and use a wider lens to match the field of view, and you adjust the iris to match the depth of field, then you can make a shot that looks absolutely identical in terms of composition, DOF, depth, spatial perception, distortion, everything.

Is it possible to make the exact same shots on a GH2 as on a 5D for instance?

Of course.

What are the differences in composition, as a result of sensor size and thus using different lenses?

The spatial perspective of the image is determined by the distance from the subject, not by the lens focal length. So if you keep the distance to the subject exactly the same, you'll have the same perspective rendering. Then, you have to use a wider lens to match the field of view, but this does *not* automatically mean that the picture will be "distorted". That only happens if you use a specifically distorting lens, such as a fisheye. Use a rectilinear lens and they will render the image identically.

 

[Barry_Green]

the wider or more telephoto the lens is, you would get more of the background or compress the background in a more pleasing way while the subject stays the same.

Only as long as the sensor size remains the same.

If you're trying to match the FOV between two different-sized sensors, from the same position, you'll find that the wider lens on the smaller-sensor camera will render the background identically to how the longer lens on the bigger-sensor camera does.

 

[Stab]

Thanks guys.

But what is this 'Full Frame Look' that people are so enthusiastic about?

 

[Amr Rahmy]

i was not clear enough, i did not mean you get more of the background or more compression, but the separation would be in a more pleasing way(not the DOF but the more linear transition of the DOF). if we exaggerate the effect a bit, if you look at a still from a medium format at f8 or more and try to match it with a 2/3 inch or smaller camera, most people would be able to point out the differences or the more pleasing image. it's like the difference between zeiss and cooke lens on the same sensor size. the cooke has a more pleasing transition in it's dof.

and you can only match settings on the fx sensor, you can't match a m43 sensor to all fx sensor settings in real life, there are no lens that can make a m43 sensor match an fx sensor in all settings.

 

[Barry_Green]

Not sure what you're saying; I'm saying the images will look indistinguishable as far as the lens is concerned. Sure the sensors may impart their own characteristics, but DOF, falloff, bokeh, if everything else is equal they will look identical. If you account for the crop factor by using a wider lens and opening up the iris accordingly, you can make them look the same.

Is there a scenario you can't match? Well, sure, if you're using a hyper-wide super-fast lens like a 14mm f/1.4, that would be difficult to match on the smaller camera, you'd need something like a 7mm f/0.7 to match that, and that lens doesn't exist. But for any rational shooting scenario, yes you can usually match the FOV and AOV and DOF between them.

 

[Amr Rahmy]

and people move the camera closer to get the subject at the right size for the same composition and to be able to focus and have the same focus falloff. and that would render a lot more than just the Shallowest of the shallow DOF is the only thing that can't be matched. a lot of composition and framing won't match.


the sharpness coupled with DOF at 1.4, 1.8, 2.0, 2.8, 4.0 cannot match and will not have the same quality and sharpness or mtf.


@stab most likely refering to 'shallow depth of field'.

 

[Ryan Patrick O'Hara]

I know that sensor size has an effect of the 'width' of lenses, the so called crop-factor.

I also understand that, in order to get comparable shots, you put wider lenses on for instance a GH2 as opposed to a 5D to get about the same composition.

But is it exactly the same shot? No, because different lenses do have an influence on the how the shot turns out in terms of depth, depth of field, distortion, etc.

Is it possible to make the exact same shots on a GH2 as on a 5D for instance? What are the differences in composition, as a result of sensor size and thus using different lenses?

Theoretically, Barry is correct. One could do the proper adjustment to focal length and F-stop and match another lens on another sized sensor.

However, as some have pointed out, including Barry, sometimes the required focal length and F-stop combo required to do so is not available.

 

[jax_rox]

Personally, the different sensor sizes affect me simply in shot workflow. When you're used to working on S35 sensors, either on actual film, or on digital cameras like RED, Alexa etc. you get accustomed to the lenses and you know what an 85 or a 50 (for example) looks like.

Then you find yourself on a 5D shoot, and you tell your AC to put an 85 on, and suddenly you're looking at around about what you'd normally see from a 50mm lens. So, I end up putting on a 100mm to get closer to what I'd normally get out of an 85mm. The composition itself doesn't necessarily change, just the way of thinking about your lensing (which took me a while to wrap my head around, after being used to S35 sensors).

 

[J Davis]

you are limited by the range of focal lengths for that sensor, for example

you cannot get the 5dm2 full frame 14mm look with a gh2

 

[Liam Hall]

Thanks guys.

But what is this 'Full Frame Look' that people are so enthusiastic about?

Full frame is great for portraits/interviews, but for general shooting there's nothing in it. Sometimes the extra reach of the smaller format is useful - either for telephoto or macro shots - sometimes the extra width afforded by the larger format is what's required. A couple of years ago I put together some clips to demonstrate this. You tell me which shots were 5D which were 7D:

https://vimeo.com/14669505

 

[J Davis]

Thanks guys.

But what is this 'Full Frame Look' that people are so enthusiastic about?

I'm going to take a stab at this but it is a subjective issue

For me the full frame look is directly tied to the ability to capture wides and establishing shots with ease given the confinements of the space you are shooting in. Especially interiors.

 

[j1clark@ucsd.edu]

I'm going to take a stab at this but it is a subjective issue

For me the full frame look is directly tied to the ability to capture wides and establishing shots with ease given the confinements of the space you are shooting in. Especially interiors.

There 's nothing 'subjective' about it. 'Full Frame', in regard to traditional 35mm Still Film film, was a 3:2 aspect ratio, or 1.5:1, not 4:3, not 16:9, etc...

So, I have no idea with people would really see that as some sort of holygrail.

If on the other hand they were referring to 35mm Movie Film film, there are a number of standard aspect ratios, but again, the 'standard' was 4:3, with matting or the number of perferations, and attendant changes in the imaging area. Lensing could also change things, as in using anamorphic lenses to get a wider view on the standard width 35mm Film film frame.

What is subjective, is which aspect ratio to use...

I personally am satisfied with 16:9 of most DSLR's and the only significant specs are spatial resolution, color resolution, and intensity resolution...

The traditional 4:3 aspect ratio is a bit 'boxy for me', and so I'll tend to 1.6, 1.78, etc... but given the 'full resolution' of the camera's use of the sensor, I'll take that over some cropping to some other aspect ratio.

 

[Ryan Patrick O'Hara]

...If on the other hand they were referring to 35mm Movie Film film, there are a number of standard aspect ratios, but again, the 'standard' was 4:3, with matting or the number of perferations, and attendant changes in the imaging area. Lensing could also change things, as in using anamorphic lenses to get a wider view on the standard width 35mm Film film frame.

Just to clarify...If I were to nit-pick, I'd clarify that anamorphic lenses are not used to get a wider FoV... they are used to achieve a wider aspect ratio without sacrificing resolution by loss of cropping. If anything, you can achieve a wider FoV with spherical lenses with better results than you can with anamorphic.

I think that is what you meant, but some could read it as meaning wider FoV, which is not the case.

-ryan

 

[J Davis]

There 's nothing 'subjective' about it.

subjective as in for me its fov, for someone else its lowlight, for another is dof ... ye get me?

 

[sonofaresiii]

Well what's subjective is how beneficial or detrimental the changes are... but that the changes exist, and in what ways, is not subjective. So there's nothing "subjective" about "Full frame look," anymore than there's something subjective about "16x9 aspect ratio." It is what it is.

 

[Barry_Green]

and people move the camera closer to get the subject at the right size for the same composition and to be able to focus and have the same focus falloff.

And by doing so, they screw everything up. Moving closer is exactly what you must not do.

 

[gonzo_entertainment]

Personally, the different sensor sizes affect me simply in shot workflow. When you're used to working on S35 sensors, either on actual film, or on digital cameras like RED, Alexa etc. you get accustomed to the lenses and you know what an 85 or a 50 (for example) looks like.

Then you find yourself on a 5D shoot, and you tell your AC to put an 85 on, and suddenly you're looking at around about what you'd normally see from a 50mm lens. So, I end up putting on a 100mm to get closer to what I'd normally get out of an 85mm. The composition itself doesn't necessarily change, just the way of thinking about your lensing (which took me a while to wrap my head around, after being used to S35 sensors).

This is one reason why a lot of use who came from a film still camera background love FF DSLR. The exact same phenomena in reverse I have a couple decades built into my brain of "A 50mm looks like this" on an S35 sized sensor it doesn't.