digicams with shallow depth of field

[apathetic]

I have a question for EVF owners. I can't afford a full-fledged DSLR, so I am looking at maybe an ultra-zoom EVF with some kind of image stabilization, maybe the panasonic FZ15. But I want something with a shallow DOF for portrait work. Does anyone know which cameras have some of the shallower DOFs?
Thanks!
jeff

[jaykinghorn]

Jeff,

Depth of field is controlled by the apreture opening of the lens, not the camera. For images with a shallow depth of field, you want a camera with a wide maximum apreture. 2.8 is ideal, though hard to find on non-SLR lenses. Look for 3.5 to 4 for a zoom camera. You will need to use a manual or aperture-select mode to choose a low f-stop. Most program modes default to f5.6 or f8, which provide an average depth of field range.

Best of luck.

Jay Kinghorn
RGB Imaging

[propwash]

The FZ15 lens is capable of using an f-stop of 2.8 throughout its range, so that camera, or one of the others in the FZ series, might work for you. However, if you plan on using the camera almost exclusively for portraits, you would probably have better luck with a DSLR with a portrait lens (at considerable extra cost, of course!)

[apathetic]

I knew that the aperature was the main factor, but I think there are other factors, like sensor size. And since most EVFs have permanently attached lenses, I was wondering if anyone knew if there were any charts or anything that compared DOF for various cameras...
Thanks for your help!
Jeff

[jamison55]

I knew that the aperature was the main factor, but I think there are other factors, like sensor size. And since most EVFs have permanently attached lenses, I was wondering if anyone knew if there were any charts or anything that compared DOF for various cameras...
Thanks for your help!
Jeff

Jeff,

In a 35mm SLR the DOF is effected by the focal length of the lens, the size of the Aperture, and the distance to the subject. The longer the zoom, the larger the Aperture,and the closer you are to the subject, the shallower the DOF. A typical 100mm portrait lens with an f2.8 aperture and a subject that is 5 feet awat will produce DOF that is almost too shallow (eyes in focus, ears slightly fuzzy...)

You are correct, however, that sensor size in digital cameras plays a HUGE role in DOF. The smaller sensors in digicams require smaller lenses. That's generally a good thing, since smaller lenses are cheaper to make - digicam makers can put nice glass into a digicam at an affordable price (and signifigantly less weight). These lenses typically have an actual focal lengths of say, 7 - 35mm. Now here's the problem...everyone quotes the lens specs in 35mm equivalent. Since the sensor on digicams is typically 5x smaller than 35mm film, you can generally multiply the actual focal length of the lens by 5 to get the 35mm equiv (7 - 35 would be 35 - 175). What people don't realize is that even though you have the equivalent zoom of a 175mm lens, you can only achieve the DOF of a 35mm lens (since that's what it really is).

Here's another way to think about it: Grab your favorite 35mm camera with a 35mm focal length lens on it. Pretty wide angle, right? Great DOF, but that lion at the zoo looks pretty far away! Now crop the picture so that only the center 1/5th remains. The lion looks pretty close now, but the DOF has not changed. The cropped image now contains the area that you would have captured if you had a 175mm lens mounted on the 35mm camera, but the DOF of a 35mm lens.

So to find a (non DSLR) digicam that can achieve shallow DOF is much more of a challenge. Let's say you find one that has an actual focal length of 100mm and an f2.8 constant aperture. Since the sensor is so small, that 100mm actual length becomes a 500mm, forcing you to push your subject 5 times further away to compose the same image (let's hope you are not trying to take the picture beside Niagra Falls!). Since the subject is now further from the camera, the DOF increases...

That is why DSLR's are best for portraits, and digicams are best for landscapes (where you want everything in crisp focus).

Having said all of that, the fast UZ's will give you the best DOF control. The Panasonic FZ series have an f2.8 aperture throughout. The Canon s1 has a max aperture of f3.1 at full telephoto. If you are really serious about portraits, however, buy a DSLR. You can get a DReb kit for $700 after rebates...

Check out this site to calculate DOF's for various digicams:
http://www.dofmaster.com/dofjs.html

[apathetic]

Thanks for the info Jamison! I played around with that javascript applet, and it looks like the FZ20 (or FZ15 in my case, less noise) will do ok. If those numbers can be trusted... I would really like to test one out to make sure though. Does anyone know offhand what amazon's return policy is on panasonic cameras, if I'm not satisfied? I know circuit city charges a ridiculous restocking fee, I hope that's not the norm...
And I am very tempted by the D-reb, I just don't know if I want an entry-level DSLR. Right now I use an old Minolta manual SLR with a very fast 50mm lense for portraits. Compared to that, when I go to the store and hold the D-reb it feels like a plastic toy...
My main problem is I'm never going to find the perfect camera, at least not for what I have to spend. I should just suck it up and make a decision. Thanks for all your help!
Jeff