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Is it a matt finish? Or did you use wet and dry to wash it?

 

You normally take such realistic photos ;)

 

I understand what you are saying, but actually it is quite realistic. The offside is lit by direct sunlight and all the surfaces that it faces are in deep shade. The car is metallic pearl and I balanced the picture for the sky so there is a lot of specular light from the paint surface that is killing the reflections. That is the way it looked at the time. The bonnet is picking up sky/cloud reflections and there are clear reflections of the nearby buildings on the front of the vehicle.

 

Here is another shot taken much later in the day with all the light coming from the opposite direction. Now the car is under-exposed and there is a lot of light on the fence and the flowers close to it so you can see them reflected.

 

20110901Prius2.jpg

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I'm sure I answered this earlier; must have pressed the wrong button.

 

Mileage, just over 12,000 mainly on short, local journeys.

 

The lens was my "walk-about"; a 24-105mm zoom used at the wide end. I would guess about 30mm.

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That's quite alot of mileage for short journeys isn't it?

 

Maybe it's the angle of the photo but it looks slightly curved to me like it was taken with a wide angle lens, like a 16 or 17mm? ;)

 

The lens I was using will not go wider than 24mm, but I'll check the actual setting when I get a chance.

 

I'm at the car service place at the moment, but I'll take a wide angle shot when I get home, to show the difference.

 

I was using a full-frame body and that makes quite a difference if you normally use a 1.5 or 1.6x sensor.

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Yeah a wide angle shot to compare would be great ;) I didn't realise a full frame body could make that much difference.

 

A 16mm lens on a 1.5x sensor will give the same angle of view as a 24mm lens on a full frame.

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That's interesting, so would there be much point in getting a wide angle lens for a cropped sensor if you're not going to get the benefit of it?

 

It depends entirely on what you want to use it for. I use Canon gear and there are lenses as wide as 10mm for use with cropped sensors.

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I checked the Exif data for the first image and it was taken with the lens set to 32mm.

 

The three pics below are taken at, respectively, 24mm, 17mm and 12mm all on a full frame sensor.

 

I tried, as far as possible, to fill the frame with car, but it's not easy with your nose on the ground . . . . :(

 

20110902Prius24mm.jpg

 

20110902Prius17mm.jpg

 

20110902Prius12mm.jpg

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Thanks for that, you can clearly see the difference between the 24mm and 17mm photos. How comes only the front of the car at 12mm is in the frame. I always thought that the wider the angle the more of the surrounding area you will get in the photo? Or have I got that wrong! :(

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Nice pics of an ugly car!! :(

 

I've only ever driven one once - a chap had skidded on the snow half into a field and was well and truly stuck.

I managed to get the car properly into the snow-filled field and then drove it at high speed downhill and across to a gate about 1/4 mile away.

Was a real pain to drive as you can't purposely spin the front wheels which I needed to do to move it about a bit.

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Thanks for that, you can clearly see the difference between the 24mm and 17mm photos. How comes only the front of the car at 12mm is in the frame. I always thought that the wider the angle the more of the surrounding area you will get in the photo? Or have I got that wrong! :huh:

 

No, you haven't got it wrong, you're just not looking at the pictures . . . . :(

 

The whole car is in the 12mm shot, but the camera is only about fifteen centimetres from the car so the closest part dominates. Wide angle lenses are commonly used for perspective distortion and since that was what you commented on earlier, I framed the shots to show it.

 

If you look at the whole scene, including the house on the right and the garage on the left, there is much more in the 12mm shot than in the others.

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Nice pics of an ugly car!! :(

 

It's all in the eye of the beholder; and it is of course, at Cd=0.25, much cleaner aerodynamically than many "prettier" cars.

 

I've only ever driven one once - a chap had skidded on the snow half into a field and was well and truly stuck.

I managed to get the car properly into the snow-filled field and then drove it at high speed downhill and across to a gate about 1/4 mile away.

Was a real pain to drive as you can't purposely spin the front wheels which I needed to do to move it about a bit.

 

Can't say that I have ever driven mine into a snow-filled field, but in quite difficult snow over the last two winters it has never put a foot wrong. In the worst conditions, I have found that it actually needs driving fairly slowly, so that you get the benefit of all the torque from the electric motors, without all the wheel spinning.

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Thanks for that, you can clearly see the difference between the 24mm and 17mm photos. How comes only the front of the car at 12mm is in the frame. I always thought that the wider the angle the more of the surrounding area you will get in the photo? Or have I got that wrong! :huh:

 

No, you haven't got it wrong, you're just not looking at the pictures . . . . :lol:

 

The whole car is in the 12mm shot, but the camera is only about fifteen centimetres from the car so the closest part dominates. Wide angle lenses are commonly used for perspective distortion and since that was what you commented on earlier, I framed the shots to show it.

 

If you look at the whole scene, including the house on the right and the garage on the left, there is much more in the 12mm shot than in the others.

 

I can see it now, there is more of the garage and the plant pots on the right hand side are closer in the 12mm shot. I think it's the distortion from the camera being so close that confused me. Other photos I've seen the whole car still looks in proportion but with just a slight perspective on it. So I assume these have been taken further back.

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If you place the camera at the same distance from the subject, you will always get the same perspective, irrespective of the focal length of the lens, but the proportion of the frame filled by the subject will decrease as the focal length of the lens decreases.

 

If you want the subject to look "normal" then it should fill the frame with a lens of about the same focal length as the diagonal of the sensor. So a full frame camera (sensor 36mm by 24mm) has a diagonal of just over 43mm, which is why the common 45mm to 50mm lens appears so often as the "standard" lens on such a camera. The focal lengths quoted are not critical; they are based on a subjective judgement of what perspective the human eye sees as normal.

 

A 1.5x sensor implies a "standard" lens of about 30mm to 35mm

 

Compact cameras with small sensors use very wide angle lenses as "standard" (my Canon G12 is only 6mm)

 

Setting up a camera with a "standard" lens so that the subject fills the frame will give an undistorted view of the subject.

 

Changing to a wider angle lens requires the camera to be moved nearer to the subject in order to fill the frame and results in wide-angle distortion, which makes the nearer parts of the subject look disproportionately large.

 

Changing to a long-focus or telephoto lens requires the camera to be moved further from the subject in order to fill the frame and results in long-focus distortion, which makes the further parts of the subject look disproportionately large.

 

Zoom lenses are convenient, but they do tend to make us lazy in the sense that the right focal length is normally the one that fills the frame without distorting the subject. So, we ought to move our feet until we are the right distance from the subject to fill the frame with the right focal length lens. Instead we simply zoom to fill the frame without necessarily thinking about whether we are distorting the image. There are obvious exceptions.

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Thanks for the explanation and yes I'm getting a 35mm prime for my cropped sensor, not the 50mm. I think if I used this on my D5000 it will only use the centre part of the lens?

 

The new photo looks 'normal' and not distorted...although I do like the other photos as well :lol: Another thing with the prime, what f number does it go down to, the 35mm I'm going to get is f1.8. I'm just wondering if it's possible to get any DOF on car photos?

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I'm getting a 35mm prime for my cropped sensor, not the 50mm. I think if I used this on my D5000 it will only use the centre part of the lens?

 

It may be a matter of expression, or perhaps there is a misunderstanding? I don't know the Nikon range at all, but if it is similar to Canon there is a range of lenses that are only usable with cropped sensors. I don't have any of them personally because the bodies that I use require full-frame lenses.

 

If you use a full-frame lens with a cropped sensor, light still passes from every part of the subject through every part of the lens, but some of the light falls outside the sensor so that the image has the same angle of view as for a longer lens. If your 50mm lens and your 35mm lens are full-frame lenses, then both will cover an area larger that the cropped sensor. If it is a 1.5x sensor, the 50mm lens will produce an image similar to that from a 75mm lens on full-frame and the 35mm lens will produce an image similar to a 50mm lens on a full frame. Both will use light passing through the whole of the diameter of the lens and you need to use the real focal length when calculating depth of field.

 

There is not really much optical difference between a full-frame lens and cropped frame lens, but the cropped frame lens can be smaller at the camera end and allows a reduction in the size of the mirror etc.

 

The new photo looks 'normal' and not distorted...although I do like the other photos as well :lol: Another thing with the prime, what f number does it go down to, the 35mm I'm going to get is f1.8. I'm just wondering if it's possible to get any DOF on car photos?

 

My 50mm prime goes from f/1.4 to f/22. f/1.8 will give plenty of scope for shallow depth of field. Your cropped sensor will make it easier to get increased depth of field. There are plenty of depth of field calculators available on line if you google and you can use them to see what is the effect of changing the various factors that apply i.e. the diameter of the circle of confusion, distance to the subject and f number. I am happy to talk more about it if you want to, but there is a lot of information readily available.

 

One of aspects of depth of field that is not commented upon very often is the effect of diffraction. Generally, you can increase depth of field by reducing the aperture size, but the resolution of modern kit is such that diffraction has become an issue. As the aperture size decreases, depth of field improves, but light is diffracted at the edge of the iris and as the aperture gets smaller the amount of light diffracted becomes a significant proportion of the total light passing through the aperture. The consequence is that the overall resolution of the image is degraded. It is difficult to generalise, but you can no longer assume that a smaller aperture always means a sharper image. I have done practical tests on the 50mm prime mentioned above and though it is capable of stopping down to f/22, I would not normally take it below f/12 because of diffraction.

 

You will notice that modern lenses, especially those designed for compact and cropped frame cameras, have limited minimum stop size. This is to avoid diffraction effects.

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so you're Prius is a girl is it ? :)

 

Where did you get that idea? I'm pretty sure I normally refer to the car as "it" . . . . :lol:

 

I notice you're still a ways off getting the offical mpg out of it tho ?

 

I didn't realise that there was an official overall mpg. If you are referring to the consumption achieved during the EC 715/2007 and EC 692/2008 tests, I have no trouble achieving those figures when the car is driven under those test conditions. On occasions, I often achieve considerably more . . . . . :D

 

20110525PriusConsumption.jpg

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It may be a matter of expression, or perhaps there is a misunderstanding? I don't know the Nikon range at all, but if it is similar to Canon there is a range of lenses that are only usable with cropped sensors. I don't have any of them personally because the bodies that I use require full-frame lenses.

 

If you use a full-frame lens with a cropped sensor, light still passes from every part of the subject through every part of the lens, but some of the light falls outside the sensor so that the image has the same angle of view as for a longer lens. If your 50mm lens and your 35mm lens are full-frame lenses, then both will cover an area larger that the cropped sensor. If it is a 1.5x sensor, the 50mm lens will produce an image similar to that from a 75mm lens on full-frame and the 35mm lens will produce an image similar to a 50mm lens on a full frame. Both will use light passing through the whole of the diameter of the lens and you need to use the real focal length when calculating depth of field.

 

There is not really much optical difference between a full-frame lens and cropped frame lens, but the cropped frame lens can be smaller at the camera end and allows a reduction in the size of the mirror etc.

 

Yes that is what I meant. The cropped sensored cameras made by Nikon are called DX. I think all of the Nikon range apart from the D700 and D3 are cropped sensors, the other 2 are full frame; aka FX. The 35mm lens I'm going to get is made for the DX sensor, although the FX cameras can automatically crop their sensors if the lens is used on them.

 

This link might help show the difference between the crops for Nikon and Canon

 

My 50mm prime goes from f/1.4 to f/22. f/1.8 will give plenty of scope for shallow depth of field. Your cropped sensor will make it easier to get increased depth of field. There are plenty of depth of field calculators available on line if you google and you can use them to see what is the effect of changing the various factors that apply i.e. the diameter of the circle of confusion, distance to the subject and f number. I am happy to talk more about it if you want to, but there is a lot of information readily available.

 

One of aspects of depth of field that is not commented upon very often is the effect of diffraction. Generally, you can increase depth of field by reducing the aperture size, but the resolution of modern kit is such that diffraction has become an issue. As the aperture size decreases, depth of field improves, but light is diffracted at the edge of the iris and as the aperture gets smaller the amount of light diffracted becomes a significant proportion of the total light passing through the aperture. The consequence is that the overall resolution of the image is degraded. It is difficult to generalise, but you can no longer assume that a smaller aperture always means a sharper image. I have done practical tests on the 50mm prime mentioned above and though it is capable of stopping down to f/22, I would not normally take it below f/12 because of diffraction.

 

You will notice that modern lenses, especially those designed for compact and cropped frame cameras, have limited minimum stop size. This is to avoid diffraction effects.

 

Thanks I will look into diffraction as never heard of that before.

 

so you're Prius is a girl is it ? :)

 

Where did you get that idea? I'm pretty sure I normally refer to the car as "it" . . . . :lol:

 

The thread title maybe? :D

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