Lens help

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Gothika

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Hey everyone. I've just got a Nikon d40 with the 18-55mm lens and I've decided I want a lens that can do this http://meemo.deviantart.com/art/Along-the-road-Green-65086331 is it called shallow depth of field? or large depth of field? anyway.. I need a lens that's able to give that type of blur/bokeh. Please don't give me any articles explaining what depth of field is because I basically know what it is, all I want help with is finding a lens. Thanks.
 
Your lens can do that... Now go read some articles on depth of field :)
 
You need a nifty fifty. :)

Basically you need a lens which is capable of low F number i.e F1.4, F1.8 etc, that's what gives you the low DOF.

I just bought a Sigma 24-60mm EX DG F2.8 to achieve something similar.

Edit:
Also What Kipax said. :)
 
I agree a nifty fifty would be better and easier... But if the OP doesn't want to know how and just wants a lens then a nifty fifty wont help at f22. Really needs to know how :)
 
KIPAX said:
Your lens can do that... Now go read some articles on depth of field :)
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my lens only goes from f3.5 (sometimes), so I don't think it can get it as blurred as the pic I showed you.
 
f3.5 can get it blurred... f8 can.. you pull out the plant and stick it in the ground furthur away from the background :) :)
 
If you have distance between your subject and the background you should be able to achieve a simialr effect with the kit lens.

Having a lens capale of F1.8 for example would make the task easier.
 
Using your kit lens....

Put a flower so it stands up on a garden table and sit yourself down so you are 2 foot or so away from it and the distant lawn etc is in the background to the flower.

Now set your camera to aperture priority and the lowest f number the lens will do. Take the picture of the flower. Repeat at various other aperture settings all the way up to f22 or as far as it goes.

Compare the results. You will see different amounts of isolation from portrait style at f3.5? to landscape style at f22. As said above - if you want more blur still then you need a bigger maximum aperture like f1.8.

edit: looks like I'm still typing too slow :)
 
RobertP said:
Using your kit lens....

Put a flower so it stands up on a garden table and sit yourself down so you are 2 foot or so away from it and the distant lawn etc is in the background to the flower.

Now set your camera to aperture priority and the lowest f number the lens will do. Take the picture of the flower. Repeat at various other aperture settings all the way up to f22 or as far as it goes.

Compare the results. You will see different amounts of isolation from portrait style at f3.5? to landscape style at f22. As said above - if you want more blur still then you need a bigger maximum aperture like f1.8.

edit: looks like I'm still typing too slow :)
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I'll give that a try but do you know of any lenses that have f1.4 to make it a lot easier? I also want the lens to have a decent zoom range because the one I have right now is only x3

thanks everyone for your replies.
 
Gothika said:
I'll give that a try but do you know of any lenses that have f1.4 to make it a lot easier? I also want the lens to have a decent zoom range because the one I have right now is only x3

thanks everyone for your replies.
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F1.4 and zoom is not going happen especially with more than a 3x range! If you want fast you need a prime I'd back every other suggestion in this thread and say get a nifty fifty it's dirt cheap will give you a 1.8 aperture and allow you to experiment.

I'd also back up all the suggestions that you do some reading and practical experimentation as you really don't seem to have a great grasp of the technical side of things and buying a new lens isn't always the answer.
 
a1ex2001 said:
F1.4 and zoom is not going happen especially with more than a 3x range! If you want fast you need a prime I'd back every other suggestion in this thread and say get a nifty fifty it's dirt cheap will give you a 1.8 aperture and allow you to experiment.

I'd also back up all the suggestions that you do some reading and practical experimentation as you really don't seem to have a great grasp of the technical side of things and buying a new lens isn't always the answer.
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yeah.. any ideas where i'd get that?
 
You need to stop and learn for a while before you make any lens buying decisions. There are other factors to consider apart from zoom range of a lens.

Use what you have for a month or two and keep reading the forum.
 
the funny thing is though.. whenever I get closer to a subject, the background becomes more out of focus. but when i'm further away from the subject it becomes more in focus. i've read on articles that it's the other way around.. what's with that?
 
Anyone notice that the shot linked to was taken at f/8 which backs up what everyone is saying - it's not the lens, it's how you use it that matters.
 
One thing to note is that the nifty fifty (50mm f1.8) won't autofocus on Gothika's D40. If you really want a fast lens (f1.4 or f1.8) then your not going to find that in a zoom. Only prime lenses (Fixed focal length, ie don't zoom) have maximum apertures that wide. (remember that a wide aperture = low f number = shallow depth of field.)

Another thing that affects the depth of field is the amount of magnification the lens can do. The more the magnification, the shallower the depth of field. This is where macro lenses come in. True macro lenses only come as primes and will allow 1:1 magnification (ie, a 1cm insect will appear as 1cm on the sensor of the camera). Looking at the image you linked to, its was taken with a Micro-Nikkor 200mm f4D ED-IF AF. While this lens wouldn't autofocus with your camera (Which is not actually that important for macro shots, but its still nice to have) There are a few that would;

Nikon 60mm AF-S f2.8
Nikon 105mm AF-S f2.8 VR
Sigma 150mm HSM f2.8
Sigma 180mm HSM f2.8

All these lenses would produce results like you are after. however be aware theta they are also not cheap options. Before diving in head first, you might want to consider options like extension tubes, buying a cheap lens like the 50mm f1.8 and reversing it or even buying macro filters.

Hope that helps. :)
 
Gothika said:
the funny thing is though.. whenever I get closer to a subject, the background becomes more out of focus. but when i'm further away from the subject it becomes more in focus. i've read on articles that it's the other way around.. what's with that?
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Nope, that's right. The greater the magnification, the shallower the depth of field.
 
pxl8 said:
Anyone notice that the shot linked to was taken at f/8 which backs up what everyone is saying - it's not the lens, it's how you use it that matters.
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yeah and he has a 200mm lens.. i only have up to 55.. i'm taking it that the 200mm has some part in that?


and thanks Messiah Khan, that was very useful. i'll consider that..
 
Gothika said:
yeah and he has a 200mm lens.. i only have up to 55.. i'm taking it that the 200mm has some part in that?
Click to expand...

Directly no, but indirectly yes. Its the magnification that is important, and generally a longer lens will magnify the image more. However if you get the 55mm lens to magnify the subject to the same size as the 200mm lens, the depth of field should be the same.
 
Messiah Khan said:
Directly no, but indirectly yes. Its the magnification that is important, and generally a longer lens will magnify the image more. However if you get the 55mm lens to magnify the subject to the same size as the 200mm lens, the depth of field should be the same.
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"magnify the subject to the same size as the 200mm lens"

sorry, would you mind explaining that?

I'm pretty new to this. lol
 
DoF has nothing to do with focal length - only magnification (how big the subject appears in the viewfinder) and aperture. So if you get the subject to appear the same size in the viewfinder you'll get the same result, to do this you simple need to get closer with a 55mm lens than a 200mm lens. But as has already been pointed out, the real trick here is to make sure the subject is isolated from the background by a having good distance between them.

The only real difference between the 200mm and 55mm is the angle of view, the 200mm has a smaller angle so it "sees" less of the background around the subject which can help the isolation effect.
 
pxl8 said:
DoF has nothing to do with focal length - only magnification (how big the subject appears in the viewfinder) and aperture. So if you get the subject to appear the same size in the viewfinder you'll get the same result, to do this you simple need to get closer with a 55mm lens than a 200mm lens. But as has already been pointed out, the real trick here is to make sure the subject is isolated from the background by a having good distance between them.

The only real difference between the 200mm and 55mm is the angle of view, the 200mm has a smaller angle so it "sees" less of the background around the subject which can help the isolation effect.
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Ohhh right. but sometimes if you get to close to a subject it won't focus
 
Gothika said:
Ohhh right. but sometimes if you get to close to a subject it won't focus
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Because all lenses have a minimum focusing distance. This is where extension tubes and macro filters come in, and allow you to focus the lens closer, at the loss of infinity focus.
 
RobertP said:
Using your kit lens....

Put a flower so it stands up on a garden table and sit yourself down so you are 2 foot or so away from it and the distant lawn etc is in the background to the flower.

Now set your camera to aperture priority and the lowest f number the lens will do. Take the picture of the flower. Repeat at various other aperture settings all the way up to f22 or as far as it goes.

Compare the results. You will see different amounts of isolation from portrait style at f3.5? to landscape style at f22. As said above - if you want more blur still then you need a bigger maximum aperture like f1.8.

edit: looks like I'm still typing too slow :)
Click to expand...
I tried what you said and this is the result from the f5.6. It was taken through the fence so the background was pretty far away so it came out quite nice.

2rqente.png
- is that called a shallow DoF?

Oh, and heres a random from my plant

35k7fao.jpg
 
Shallow DoF is normally shooting at f/4 or wider (lower numbers) but also depends on the magnification. The greater the magnification the less DoF you'll have - take a close up shot and there'll be a lot less DoF @ f/5.6 than you'd have for a landscape shot focused at infinity.

The effect you're after isn't so much about DoF as it is about distance between subject and background. Try the following test.

Get some object as your subject and set up with it at min. focus, 55mm, f/5.6. Now take several shots where the background behind the object is at varying distances from a couple of feet to as far as you can get it. The further away the background the more blurred it will be.
 
pxl8 said:
Shallow DoF is normally shooting at f/4 or wider (lower numbers) but also depends on the magnification. The greater the magnification the less DoF you'll have - take a close up shot and there'll be a lot less DoF @ f/5.6 than you'd have for a landscape shot focused at infinity.

The effect you're after isn't so much about DoF as it is about distance between subject and background. Try the following test.

Get some object as your subject and set up with it at min. focus, 55mm, f/5.6. Now take several shots where the background behind the object is at varying distances from a couple of feet to as far as you can get it. The further away the background the more blurred it will be.
Click to expand...
min focus? so you mean come further away from the subject?
 
The object you're focused on is at the min. focus for the lens, it's the background that should get further away with each shot, eg.

1st shot, object at min focus, background is 2 ft away
2nd shot, object at min focus, background is 10 ft away
3rd shot, object at min focus, background is 50 ft away
and so on...
 
pxl8 said:
Shallow DoF is normally shooting at f/4 or wider (lower numbers) but also depends on the magnification. The greater the magnification the less DoF you'll have - take a close up shot and there'll be a lot less DoF @ f/5.6 than you'd have for a landscape shot focused at infinity..
Click to expand...

Technically they are not lower numbers, but higher, they are fractions.
1.8 is 1/1.8
2.8 is 1/2.8
4 is 1/4
etc etc...
 
So much for trying to keep things simple for the op

:bang: :bang: :shrug:
 
Sorry :P
I found F numbers really confusing till someone explained that to me.
"Lower means more... what?"
 
Messiah Khan said:
Nope. Would be a bit drastic to switch system just for a dof preview button though.
Click to expand...

Would also be totally pointless when shooting wide open as the lens will already be at it's widest setting when focussing so the DOF preview button will do nothing at all.
 
The way i remember f stops is the lower the number on the camera (ignoring the fractions) the lower the depth of field. but as said the distance of the background makes a big difference.
 
:clap::clap::clap: wow ... I salute you lot for the patience and effort you've given the DoF matter to someone who wasn't willing to read an article about this! :clap::clap::clap:
 
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