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10/25/2003 11:03:57 AM · #1
How do you get a blurry background with a digital camera? I have tried everything, closeups, macros, soft portrait. With my 35mm, I just set the portrait mode and it takes a photo crisp of the foreground and blurry in the background.. why can't I get this effect with my digital? am I doing something wrong?

10/25/2003 11:07:09 AM · #2
if you really want to blur the background set the aperature wide open (2.8 or lower number if you have it) if you don't have an aperature setting with your camera auto focus on something very close and then it should blur the background more but the subject you're photographing may come out a bit blurry also if you do that.
10/25/2003 11:15:10 AM · #3
Originally posted by FullyFocused:

How do you get a blurry background with a digital camera? I have tried everything, closeups, macros, soft portrait. With my 35mm, I just set the portrait mode and it takes a photo crisp of the foreground and blurry in the background.. why can't I get this effect with my digital? am I doing something wrong?


The principals of optical physics works with all cameras, whether digital or film. Depth of field is controlled by the size of opening in the lens, otherwise known as aperature. When the blades are adjusted to create a large opening, this lets in lots of light and creates a narrow or shallow depth of field. (Aperature setting of 2.0 or 2.8... like in portrait mode, the subject is crisp, but the background is blurry). At a higher aperature, say f 8.0 (for a digital point and shoot) or f 26, or f 32 on a DSLR lens, the opening in the lens is small, resulting in less light coming through, but a very deep depth of field. (ie, foreground, as well as distant background in focus).
Keep in mind that you cannot equate SLR aperature settings to point and shoot settings. As I mentioned at the start, this is all based opon physics. The size (diameter of the lens) and therefore the diameter of the aperature opening affects your depth of field. F8.0 on a large SLR lens is not the same size opening as F8.0 on a smaller point and shoot lens. F8.0 on an SLR is middle of the road depth of field, where F8.0 on a point and shoot is often its smallest opening and results in very deep depth of field.

I am not familiar with the controls on your camera. If you have an 'aperature priority' mode, try taking some test shots. This is where you set the aperature and the camera's metering system decides on the shutter speed for a propper exposure.
Set the camera on a tripod or other stable place where it will not move. Take shots of a stationary subject, changing the aperature setting each time. Compare your resulst on the computer, you should see a gradual change of your depth of field through the series of shots.

I sort of got to rambling, but I hope there is enough information in here to help you out!

JD Anderson

Message edited by author 2003-10-25 11:16:00.
10/25/2003 11:24:25 AM · #4
Thank You... I will check to see if my camera has those settings. It's frusterating sometimes seeing people who have these camera's that are cheap, yet they get professional photos out of them, and I can't do anything they can do with theirs.. I am working on it though.
10/25/2003 11:42:50 AM · #5
You might check out these two tutorials if you haven't already:

Cheap Enhancements for "Low End" Digital Cameras

Blurring a Background in a Portrait
10/25/2003 12:13:02 PM · #6
This is perhaps overly simple advice but, I find that if i am close to my subject and the background is further away I have better luck. That vs. being far from subject and background.
10/25/2003 12:38:58 PM · #7
Karen,

I just checked and noticed that your camera, Sony Mavica CD350, has few manual settings available. It is fully automatic for aperture and shutter speed and those are the main controls you need to achieve the results you want.

It has a three "area" autofocus system. However, it does have a 5 position manual focus override you can try playing with to get a soft-focus background, but I suspect you will have only limited success.

For the most part, it is specifically designed to give you a crisp, clear image with nothing out of focus every time. Sorry about that.

Message edited by author 2003-10-25 12:41:54.
10/25/2003 12:58:32 PM · #8
Karen,
I also looked over the specs for your camera, and it does have both a portrait and "twilight portrait" mode. I would hope that one or both of these would use the largest aperture.
The real issue is that, as Smelly stated, you can't get around the physics. Your max aperture is F3.9 at full zoom, which is not very wide, and the lens focal length is 6.4x smaller than equivalent 35mm focal length. So your DoF for F4 is 6.4x larger... you get the picture.
Your best bet is to work at full zoom, F3.9, and try to keep your subject well in front of your background.
I ran a DoF calculation for your camera with F4 and a 10 ft. distance to the subject, the DoF is about 3.5 feet (8.6 to 12 feet). You can run the DoF calculations here.
Hope this helps.
10/25/2003 01:26:38 PM · #9
Simple aperture settings aren't going to help you a great deal with an automatic, point-and-shoot camera. Aperture is just a ratio between the size of the smallest opening in the lens barrel, and the focal length of the lens. A smaller number means a larger opening. This is the same whether it's a lens on an SLR or a tiny point-and-shoot. The reasons that there are smaller aperture ranges on fixed lens digital cameras are several. The first is that the lenses on these cameras are very small and an opening required to achieve an aperture of F22 would be very difficult to engineer given the typical leaf design of the aperture on a camera. For a focal length of 9mm on a digital camera, that would leave an opening of 9/22mm or less than half a millimetre, which would also introduce optical issues. The main reason, however, is that smaller apertures than about F8 aren't usually needed by the type of photographer that buys one of these prosumer cameras. F8 is enough to satisfy nearly all uses, as explained in the next bit.

What you're trying to achieve is a shallow depth of focus. This is dependent on four things:

1. The absolute focal length of the lens (not the 35mm equivalent).
2. The size of the sensor.
3. The maximum aperture of the lens.
4. The distance to the subject.

1, 2 and 3 are working against you with your Sony, in a big way. Consider that the focal length on your camera's lens is 6.4-19.2mm, the sensor size is 5.27 x 3.96mm (nothing to do with the number of megapixels on that sensor) and the maximum aperture is F3.8. Compare this to a Canon 10D/300D which has a sensor size of 22.7 x 15.1mm and a number of lenses available, of which the very shortest from Canon is 14mm and the longest is 1200mm, and lenses which can be opened to a very large maximum aperture (F/1.2 is available in an 85mm lens). A good portrait lens (one which is designed to give good background blur) is typically 70-200mm in focal length, or nearly 10x as long as your Sony's lens.

You don't need to know the physics behind the reasoning for the above, but suffice it to say, you're not going to get a lot of background blur compared to a camera with a large sensor and a really long focal length. This can either be a good thing or a bad thing, depending on your needs. For landscape photographs, your camera has an advantage in that most everything in the scene is in focus, even at large apertures. This is the main reason why smaller apertures aren't needed on point-and-shoots. The main effect of stopping down on an SLR is for a large depth of focus as shutter speeds on DSLRs of 1/4000th and greater can usually handle really bright light well. I have to think a bit with my 10D, and use a tripod, to get the same depth of focus that even my F717 can produce handheld. I have more problems keeping everything in focus in a scene than I do throwing something out of focus.

As others have said, your best results will be a the largest maximum aperture you can set, the maximum zoom (to maximuze the focal length) with your subject as close to the camera as possible. With my old DSC-S50 I found that finding a dark or uniform background that is very far away works best for portraits, as the darker and further away things are in the scene, the more it is out-of-focus and unobtrusive, and the more your subject stands out.

This whole issue is one of the main reasons why people spend thousands of dollars on SLR equipment.

Hope that helps.

James.

Message edited by author 2003-10-25 13:38:09.
10/25/2003 02:09:40 PM · #10
You guys are ALL SO HELPFUL! Thank you all so much for looking up my camera info. I went with the CD Mavica because of it's crisp bold photos and GREAT quality. Not to mention how convienient the CD is and it holds up to 120 photos per CD. Me being into the 35mm camera's all my life, maybe I should have done my homework with purchase of the Digital camera. Maybe it's time to look into a new Digital Camera. Don't get me wrong, it takes BEAUTIFUL photos, it's just now I want to play around and it's harder to find those options.
10/25/2003 02:40:57 PM · #11
Perhaps look into the Mavica CD500. 5 megapixel, and it has every manual feature you can think of. I have the CD400, which is just one generation old. The CD500 has fully manual aperature and shutter speed, it has the exposure historgram, fantastic lens from sony, and just about everything else you can think of.
10/25/2003 04:24:45 PM · #12
With all respect to Steve, I'd recommend against getting another Mavica if you're really into DOF flexibility. The F717 is probably the lower limit of what I would consider becoming acceptable enough in this regard. I find that I can get good background blur for a portrait, but only really for a headshot, and only if they're fairly close to the camera. The conditions have to be precise and I have to be quick. Some examples of good blur, and also from further away at full telephoto and max. aperture, to show how selecting a good background is important.



Conversely, the 10D and is able to produce blur even from very far away. The kid sitting was about 20 feet away, at F4 and 320mm (as opposed to the F2.4 and 5 feet away at a 200mm field of view for the couple shot from the F717 above) the shots of the guys running were from 50 feet at least about 100 feet away at a 320 mm FOV. Even with the busy backgrounds the subjects still pop out. The last one shows that even with a 50mm lens you can get very good blur for portraits with the 10D.

10/25/2003 11:28:29 PM · #13
Thank you all for your great info.. I did however take awesome shots of a nascar driver with my Nikon 35mm using a 70-300 lens and the background was BEAUTIFUL and blurred out. I am dissapointed now that I got this CD Mavica, I dont have much money for a real fancy Digital Camera, but I am looking into the Sony DSC-F717 or the Nikon D100..

Jimmy, I hope you don't mind me e-mailing you a couple of my photos.. maybe you can give me some tips. I would post my photos here but I haven't joined to be able to challenge yet, I will be this weekend.

Karen
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