cheapest Camera that will do depth of field
- Thread starter easyrider
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Caporegime
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DoF is also dependent on aperture and sensor size too.
I assume you are looking at portraiture??
A budget dSLR and a 50MM would be a start.
I assume you are looking at portraiture??
A budget dSLR and a 50MM would be a start.
Soldato
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Erm, all cameras have depth of field.
I'm guessing you want to shoot sharp photos with blurry backgrounds.
Basically you want a large sensor and a wide aperture lens. Probably the best bang for buck with be an entry level DSLR with a prime lens.
Nikon D3200 + Nikkor 35 f1.8 DX (I think there's one in the members market at the moment). There will also be a similar Canon or Pentax.
I'm guessing you want to shoot sharp photos with blurry backgrounds.
Basically you want a large sensor and a wide aperture lens. Probably the best bang for buck with be an entry level DSLR with a prime lens.
Nikon D3200 + Nikkor 35 f1.8 DX (I think there's one in the members market at the moment). There will also be a similar Canon or Pentax.
Soldato
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Its for some students who need to take still pictures with blurry backgrounds and blurry foregrounds.
I have a Sony NEX 3n
If you want a camera that yields a large Depth of Focus then you want a small sensor compact, your smartphone is ideal.
If you want a shallow Depth of Focus then you want a lens with a long focal length and a large aperture. You also want to get closer to your subject.
Contrary to popular belief however, sensor size has no direct effect on DoF. There is an indirect effect because you will use a longer focal length to get the same subject magnification when the distance to the subject remains the same, conversely if you use the same focal length then to maintain the same subject magnification you will need to get closer.
The only thing a larger sensor allows is for you to get closer, or to use a longer lens. (although at macro and hyperfocal focal distances things changes a little).
If you want a shallow Depth of Focus then you want a lens with a long focal length and a large aperture. You also want to get closer to your subject.
Contrary to popular belief however, sensor size has no direct effect on DoF. There is an indirect effect because you will use a longer focal length to get the same subject magnification when the distance to the subject remains the same, conversely if you use the same focal length then to maintain the same subject magnification you will need to get closer.
The only thing a larger sensor allows is for you to get closer, or to use a longer lens. (although at macro and hyperfocal focal distances things changes a little).
Soldato
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The sensor in the Nex is the same size as the entry level Nikons, so you will be able to get relatively shallow depth of field by just getting a fast lens. Cheapest will probably be a 50 or 35mm f1.8 or something similar, I don't know the Nex range that well.
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Just because you're technically correct doesn't mean it's not incredibly unhelpful that you say this in every DoF related discussion particularly when people who are new to the idea are concerned. For every real world situation, any time you capture the same framing of an image (which inherently means the same field of view i.e. longer focal length), a larger sensor will give you a shallower depth of field at the same aperture.
Soldato
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That is only valid if you can keep the same framing. If you don't own a longer lens or can't get closer to the subject then there is no difference in DoF between a FF and crop sensor. This is a very real scenario for wildlife photographers where it is desirable to have good subject separation and isolation, especially against busy background foliage. Their longest lens might be a 400mm f/5.6 and the distance to the subject is a constant, therefore the achievable DoF is identical on a FF body or a crop body.
This is a very real scenario that many people will encounter so it is wrong to believe the sensor is having any real effect on the DoF.
It is also confusing when people say the aperture changes with different sensor sizes or the focal length. Go grab a ruler and measure the diameter of the front element while it is mounted on a crop camera. Now mount the lens on a FF camera and measure again. Interestingly the aperture stays the same despite the sensor size changing
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Soldato
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Yes and the easiest and most obvious way of thinking about it.
The rest is just stuff no one ACTUALLY needs to know. Ksanti is right. All the guff you mentioned is actually very unhelpful for the Op.
No, it is very helpful to understand what is going on. Focal lengths and apertures don't change with different sensors, it is confusing to think that way.
I clearly explained that aperture, focus distance and focal length are the important variables and that with larger sensors you can either get closer or use longer lenses which reduce the depth of focus.
A 50mm f/1.8 lens has the same DoF on a FF or crop camera, no need to make a confusing statements like "the effective aperture is increased to f/2.8". The important thing is field of view will be very different and the subject different sizes, that is the only thing that has changed. If you were to get closer to increase the subject size to match then the reduced focus distance changes the depth of focus, the sensor hasn't done anything. This is a much more natural way to think of it.
To me (relatively new to this)
You want longest lens with smallest F number that is decent at low F numbers
Bearing in mind what you need to frame!
And how far you can get the background to be from the subject!
50mm 1.8 is probably the likely target imo
You want longest lens with smallest F number that is decent at low F numbers
Bearing in mind what you need to frame!
And how far you can get the background to be from the subject!
50mm 1.8 is probably the likely target imo
Interesting that your the only person who thinks this is the easiest way to think about it that I have encountered!
OP any slr or CSC with a fast telephoto prime will do what you want if you want cheap go second hand and a few generations old a 30D or 400D and a 50mm f1.8 will cost very very little and do exactly what you desire.
That is because most people first encounter the confusing and counter intuitive version of effective focal lengths and magical change to physical characteristics of an object simple by placing it on a different camera.
It is like saying I have an apple in my hand that is 50mm in diameter and weighs 200g but if u give it to my wife who is smaller and lighter it is equivalent to a 75mm apple that weighs 300g. It just doesn't make sense.
That is because most people first encounter the confusing and counter intuitive version of effective focal lengths and magical change to physical characteristics of an object simple by placing it on a different camera. It is like saying I have an apple in my hand that is 50mm in diameter and weighs 200g but if u give it to my wife who is smaller and lighter it is equivalent to a 75mm apple that weighs 300g. It just doesn't make sense.
Sure, the apple looked relatively bugger in my wife's hand because she is smaller but the apple is the same size. It is more natural to realize the physical properties of the lens don't change but other factors are at play. The first thing to understand is how sensor size changes the captured field of view. A smaller sensor samples a smaller sub-region of the image projected by the lens compared with a larger sensor. The image projected by the lens is again a constant independent of the camera, we just record different sized areas of it. By understanding this it is clear that a larger sensor capture a wider angle of view and so the subject would be smaller within the frame relative to a camera with a smaller sensor.
This is clause 1: sensor size effects the field of view angle (i.e. subject size) for a given lens.
This is something beginners frequently don't understand, and get confused that a DX/EF-S lens that is 35mm is the same as an EF/FX lens that is 35mm and project the same image on a crop camera. Understanding the DoF in the correct terms is actually much easier for beginners than understand the crop factor in my experience.
Now DoF is easily explained by 3 properties:
A) Focal length of the lens
B) Focal distance, e.g. distance to subject.
C) Lens Aperture
Thus, putting the same lens on a cameras with different sensor sizes doesn't change DoF, but is does change the field of view. Taking into account clause 1 above WRT the image field of view, it is clear that applying properties A) and B) will alter the DoF. Of course changing the lens or getting closer will change the DoF, properties A) and B) indicate this. The same applies on an APS-C crop sensor, m43 sensor, 1", FF, MF etc. The same knowledge can be applied to whatever camera you own. This is a much more powerful concept that is not only physically accurate but is useful in situations where maintaining the same subject size within the frame just isn't possible (perhaps you can't physically get any closer due to a wall/fence/cliff/danger, perhaps you don't own a longer lens, perhaps you are at the MFD and can't focus closer).
Scenario 1)
If someone enjoys a 24mm lens on their crop camera and upgrades to a FF then it is important to know that 1) the image will be much wider, 2) The DoF wont change. They might get closer to the subject, but e.g. shooting people 24mm on FF means you are getting uncomfortably close. So yeah, they need to buy a longer lens. It is that longer lens that will change the DoF.
Scenario 2)
Someone likes shooting wildlife and has a 100-400mm F/5.6 lens. He wants to get 'better' images and hears he should buy an expensive FF camera. Upon acquisition he goes out to shoot his favorite stag in Richmond Park but finds the deer looks much smaller in the frame, which he knew would be the case and thought he would just need cropping or get closer to the deer. The thing is, you can only ever get so close to an animal (and you shouldn't approach any closer than about 100ft anyway so you don't disturb it, and for safety reasons). More disappointingly the FF camera hasn't reduced the DoF at all and the busy foliage in the background is just as distracting as ever.
The person really needs to either buy a faster lens or a longer lens. Buying a longer lens will help regain the subject size and reduce the DoF as desired.
Scenario 3)
Someone shoots still life on a budget with a 50mm prime. They shoot the lens at or near the minimum focus distance. Someone lends them a FF camera and they get excited in the ability to have a shallower DoF. Except at the MFD the larger sensor doesn't directly give any difference to the DoF because the focal length is unchanged and the distance to subject is unchanged. How disappointing.
Scenario 4)
Someone shoots a 50mm prime on a DX body and wants to shoot weddings. They upgrade to a FF camera and 85mm lens. they enjoy shallower DoF because of the new lens the larger sensor allow them to use.
Not everyone is in Scenario 4. Moreover, talk of effective apertures and focal lengths can be useful and has a time and place but in my experience it is more confusing to beginners to talk about such things than if they just understand the basics of what is going on. It is very clear that larger sensors allow longer focal lengths, the rest is trivial.
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