|
Re: Here is what you need to know
In reply to slimandy,
6 months ago
|
slimandy wrote:
primeshooter wrote:
slimandy wrote:
That's not quite true. If you use a longer lens but you want the same framing you will stand back more and the resulting DoF will be about the same. However, the narrower FOV will give you more BG blur.
Example,
lets say you used the 35mm f1.8 wide open then used the 85mm f1.8 wide open but framed the subject in the same way....
35mm @ f1.8 from 3.5 feet..... DOF is 0.21 feet.
85mm @ f1.8 from 8.5 feet.... DOF is 0.21 feet.
So both lenses give you the same DoF and both are shallow enough for a blurred BG. The difference is the longer lens gives a narrower FOV so the BG is blurred more.
--
www.andrewsandersphotography.co.uk
Sorry? I said using a long lens gives more out of focus elements compared to a short lens which is true. OBVIOUSLY if you change the framing when you compare a short and long lens then it will change this! Just like if you changed aperture when you compare it's not really a fair comparison, eh?
I also explained getting closer gives more isolation...I explained through various points what affects dof, if you change variables when comparing then come out with a blanket statement that both lenses above give the same dof in your described situation- whilst not untrue, it's not comparing like for like and certainly doesn't change the fact that long telephoto lens can isolate subjects much better.
What you said was......
"Lastly focal length, the longer it is the more you can isolate a subject and have decreased dof.
With all this in mind, you'd be better buying a 50 or 85mm 1.8 or 1.4"
... and I have shown this isn't accurate. If you frame the shot like the example given by the OP your DoF will be the same. My figures for DoF we from DOF Master.
--
www.andrewsandersphotography.co.uk
Actually his intention is quite clear from his writing, he said - "Have any of you been able to get this kind of DOF out of the 35mm 1.8? I guess I have when I'm, like, two feet away."
When he is close he realises he can get this sort of reduced dof. He wants to be further away, and likely have the ability to blur the BG more when he is close. Longer lenses will do this. I'm pretty sure wildlife photographers don't go out and buy a 400mm 2.8 in order to stand about the same distance as a 50mm to give the same dof. They do it to get closer magnification (whilst staying far away from subject) and blow out the background, which is what he is talking about. If he kept buying longer lenses and standing miles away from the subject yes he wouldn't notice a difference, this is kind of obvious though isn't it?
| Post (hide subjects) | Posted by | When | |
|---|---|---|---|
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | 1 | ||
| 6 months ago | 1 | ||
| 6 months ago | |||
| 6 months ago | 1 | ||
| 6 months ago | |||
| 6 months ago | 2 | ||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | 1 | ||
| 6 months ago | 1 | ||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago | |||
| 6 months ago |
   |
|
Connect with dpreview
|
