| Author | Thread |
|
|
05/09/2004 05:26:19 PM · #1 |
The digital photography is knew to me and I haven't had the school of analogic photography to be able to compare... So I render myself the the wisdom of other with far great experience. So I describe my major problem with my Fuji S5000:
I find very hard to acomplish photos like portraits where my subject is in focus and the background is blurry. Almoust always the background is less blurry then I whished it would be. And a bit like that happens when I want to limit the DOF, keepping the things in front and at the back out of focus and a sharp subject.
I readed before that some tricks might help, like getting away of the subject and zooming in, but (probably because of me) I have found this to be litle or no help. Only when I'm almoust at the end of the zooming range (10x) or the background is too far away it gets pretty blurry.
- Does it help putting in macro mode or does it only permits cose focus?
- Does it help if I use a teleconverter?
- Any more trick anyone?
So if anyone could help I'm all ears (to read). thank's in advance. |
|
|
|
05/09/2004 05:29:02 PM · #2 |
| It's all about the Aperture or F#. Do you have some samples in which you need help? |
|
|
|
05/09/2004 05:30:20 PM · #3 |
One method is to shoot your subject at the widest possible lense opening (lowest f/number) possible. In your case that is f/2.8
This produces the shallowest DOF. Combine this with moving your subject as far as possible from the background and that should help.
Message edited by author 2004-05-09 17:32:42.
|
|
|
|
05/09/2004 06:08:06 PM · #4 |
I have the same problem, and regularly receive comments about it in the challenges.
The true aperature on our cameras is nowhere near f2.8 in real terms.
Only suggestion I have is use it at full zoom and this helps to lessen the dof. |
|
|
|
05/09/2004 06:22:42 PM · #5 |
| The background blurriness is also related to how many blades are used to form the iris in the lens. I'm not sure how it is related, but I think it has something to do with the smoothness of the blurring. |
|
|
|
05/09/2004 07:47:40 PM · #6 |
The problem is not that the aperture is not really f2.8, but that for small sensors, the focal length of the lenses is quite short. This means that for a given f ratio, it will have deep DOF.
My small digicam (Digital ELPH) has a 5.4mm-10.8mm zoom. This lens will always have a much greater DOF than a lens that gives an equivalent view on a bigger sensor.
The number of blades and their shape doesn't have any effect on the DOF, but does affect how the BG is blurred.
|
|
|
|
05/09/2004 11:14:18 PM · #7 |
I have recently started blurring Background using PS. I simplyb use lasso tool to outline area i am interested in blurring than use Gausian blur.
It is very effective.
|
|
|
|
05/10/2004 08:00:14 AM · #8 |
This confused me forever in my transition from film to digital, but I finally found some discussions that made it make sense.
The issue is sensor size. Only the very top of the line DSLRs have sensors even close to the same size as a frame of 35mm film. Many of the digital cameras available have sensors smaller than 12mm!!!
It's a really complicated thing to describe, but the easiest way I know to describe it is this... an f stop is a ratio. It's a ratio of focal length to opening diameter. When the sensor gets smaller, the focal length gets smaller (those big numbers you see are often 35mm EQUIVALENTS, and the actual lens focal length is often less than 10% of the equivalent), so at a given f stop, the ACTUAL DIAMETER of the iris opening is also smaller on the digital than on the 35mm. Due to the fact that the subject and the background are the same for both photos (pretending we are shooting a 35mm film camera and a digital side by side), MORE of the photo is going to be in focus for the digital than the 35mm. As well, the parts of the photo that are out of focus (the background) will be MORE out of focus on the film than it will be on the digital. There are "degrees" of blur - the pertinent language here is "circle of confusion" and to get a "lot" of blur, you need to have BIG apertures and big sensors.
To accomplish the amount of "blurring" in a background that you are accustomed to seeing with a 35mm and f2.8, you will need to do one of these things...
1. Use a top of the line Digital SLR with a large sensor - in other words, spend a lot of money.
2. Use Photoshop techniques with the lasso tool and Gaussian blur.
I hope my feeble attempt at explanation at least makes some sense.
|
|
|
|
05/10/2004 08:07:23 AM · #9 |
have the subject be farther away from the background.
then you can use your comfortable shooting distance, and acheive a blurrier BG
|
|
Home -
Challenges -
Community -
League -
Photos -
Cameras -
Lenses -
Learn -
Help -
Terms of Use -
Privacy -
Top ^
DPChallenge, and website content and design, Copyright © 2001-2025 Challenging Technologies, LLC.
All digital photo copyrights belong to the photographers and may not be used without permission.
Current Server Time: 06/12/2025 07:18:05 AM EDT.
