photography q
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- jakeyj
ok lets first establish that i'm a total nOOb at photography. I just got my first camera like 3 months ago. it is a point and shot canon s70.
my question is, is it possible on a p and s camera to keep your subject in focus and blur the background? i've tried opening up the aperature and zooming and all those other tricks, but my whole picture is in focus unless i'm in macro mode. is there any way to do it.
thank you kindly for any help you can offer me.
- Visia0
hmm, first off you're on the right track. A wide-open aperture will give you a shalllow depth of field (blurred background). And, it
s a common misconception that the lens size also plays a role, that telephotos will give a shallow depth of field. This isn't so.But, in this case I'm not sure what the issue would be. Possibly that your lens isn't "fast" enough to stop down to provide the desired effect.
When you're shooting wide open what is your aperture setting?
The only other thing that I can recommend is that you fill more of the frame with your subject and also put more distance between your subject and your BG.
Hope that helps.
- canuck0
With your camera probably not the depth of field is probably quite wack.
my digital is a canon s45, you probably have similar settings, Portrait mode seems to give the best results.
But you really need a slr (or dslr) to get some decent results.
- jakeyj0
yeah that's kind of what i thought. i haven't tried portrait mode though so i'll play around with that a bit.
thanks
- vespa0
if you can do aperture priority i don't see why it doesn't work.
so you've got your aperture right open at f2.8, which means your shutter speed will be pretty fast to get the correct exposure. the depth of field should drop away pretty sharply.
i'd never go below f5.6 for a portrait in case you get the nose in focus and the eyes out of focus.
- ********0
I've heard that the smaller sensorsa on most digital cameras produces a depth of field multiplying effect; ie same aperture has wider fepth of field than equivalent film.
- Visia0
that might be true Rand. I find that I have a similar issue with my Canon 300d. Wide open for my lens is f/4 but I still don't always get the shallow DOF that I'd like. The sensor crop would likely be the issue.
- vespa0
that's interesting, i didn't know that Rand.
i was wondering why that camera only went up to f8 - seems a bit shallow but would make sense if it's actually wider. how confusing tho.
- jakeyj0
on my camera, the lower i set my aperature (like 2.8) my shutter speed gets slower like 1/50. shouldn't it go the other way?
- vespa0
??
yea it should get faster.
fully open aperture > more light gets in > less time required to exposeso what shutter speed is it when you stop it down to f8?
- jakeyj0
yeah that's what i thought. i don't have my camera with me but when it at f8 the shutter is like 1/250. as i close the aperature the shutter speeds up. i don't get it.
- vespa0
mmm but your shots are still correctly exposed? that doesn't make sense.
are you sure you're not getting confused with the fact that as the aperture opens up more, the number goes down? i.e, f2.8 is fully open (but is a small number) and f8 is closed down (but is a higher number)?
anyways i gotta go but best of luck.
- jakeyj0
yeah, at least i'm pretty sure. as i open up the aper. (making it a lower number) i can watch the shutter speed slow down.
if i open the aperature and manually crank up the shutter speed, the picture gets totally underexposed. even in decent light.
weird. thanks for the help tho.
- haha0
You guys are all on the right track.
Larger the apeture (i.e. 1.4 or 2.8) less depth of field.
Also the longer the lens, the less depth of field.
And also the size of the chip in the camera, makes a big depth of field.
The small size of the chips in a lot of point and shoot cameras also are a big factor.That is why back in the film days, a shot on 8x10 or 4x5 with a wide apeture, has a lot less depth of field than a equivolent fstop on a 35mm.
Try shooting on apeture mode (or portrait mode). Shoot as wide open as you can. Use the longest lens you can (zoom out if you can) and put some distance between your subject and background.
I hope this helps.
- jakeyj0
yeah that's what i've been trying to do. the problem is when i set it down to 2.8 my shutter speed has to be at like 1/25 or something to even get some exposure. but then its blurry unless i use a tripod.
i probably just won't be able to do it i guess. thanks tho
- jakeyj0
can anybody else help me out?
or its is not possible with my camera.
- alex_0
Haha is spot on.
You're not going to get the same effect as you would using a SLR for many of the reasons haha mentioned.
Along with using widest aperture and putting distance between the subject and the background, you can also get closer to the subject. Basically the closer you get to the subject the narrower the DOF(depth of field is). The problem with that is you will probably start to get some distortion from the lens.
Another thing is you can use a flash to give some seperation, but it probably isn't what you're looking for.
The main culprit with P&S cameras IS the size of the sensor along with the short focal length.
- haha0
the problem is when i set it down to 2.8 my shutter speed has to be at like 1/25 or something
jakeyj
(Aug 8 05, 10:39)The rule is: the wider the apeture, the faster your shutterspeed can be.
More light in the lens, less time the shutter can be open.So if you are getting faster shutterspeed as 1/60. 1/125 etc. at f/5.6-f/22 you are in a place shootingthat has more light than in the space where you are getting 1/25 at 2.8.
Use a tripod, or a flash or two.
Those are the problems that all of us photographers face.If this doesn't answer your question, maybe I just don't understand what you are asking.
Hope this helps
- Visia0
haha, I actually read an article the other day where a guy did an experiment with several lenses from wide to tele and shot everything at the same aperture setting. What he found was that there wasn't a difference between the lenses but rather the distance the photographer was standing.
I can't remember where the link was but I'll post it. Really interseting. I can't say it's 100% but . . .
Anyway, jakeyj, I think you're either reading your settings backwards or your sensor is fucked. If you open up to 2.8 (in a sunny daylight setting) then you should be able to shoot waaaay higher than 1/25.
But, like HaHa said, lack of light volume is a bitch. I was pondering that the other day . . . I wonder why it is that "science & technology" can't supply a sensor that has a higher sensitivity range. I really wouldn't care if it doesn't match the characteristics of film, I'd rather be able to shoot at 1/125 than 1/30. Although I do get some lovely blur effects by accident.
I also wish that ISO 3200 wasn't so damn noisy. Grain is beautiful, noise is shit. And I haven't seen a "noise removal application" that doesn't completely fuck up my photos.
- haha0
visia
I can't remember what i said (without rereading my posts) but it has always been my experience that long lenses do things with compression and depth of field that wide lenses dont (at the same fstops) Yeah but that distance thing does make a lot of sense.
I'd be interested to read that article tho...I hope you can find it.
Also, Visia what camera are you using? Just curious. It would be awesome for the new stuff to have higher ISOs that are noise free. Nothing is greater than natural light and it'd be nice to take advantage of it in most situations without the slow shutter speeds.
Oh and jakeyj, what visia said.
- Visia0
yeah, I always thought that too. But when I read the article it was very convincing. I can't seem to find it but I'll keep looking.
Anyway, I'm shooting with a Canon 300d. It works great for creatives or model testing but I'd certainly rent out a D1 or something for any commercial jobs.
I find that the highest ISO setting I can use is 200, and then I have to make sure I'm bang on with my exposure (which I'm ususally not so . . .) otherwise I get nasty noise. Drives me nuts. I used to love shooting high ISO films and getting a beautiful grain.
That's the only thing about digital that I don't like better than film.
But, with that said, adding grain artificially in Photoshop tends to be a good solution for getting the grainy look and/or covering up noise. It's just a pain in the ass to have to go through that second step.
What is it that you shoot with?