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@Forkbeard you could try this http://www.dofmaster.com/doftable.html or download an app for your mobile.
Mike
Mike
and please use their services
Beginner Really struggling
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in truth f-stops are not a distance but a scale. hence its not really possible to say what amount will be in focus in terms of inches/feet etc due to the number of variables ( distance from subject etc. so all you can do is estimate based on the guide of focus area in front and behind subject which normally equates to 1/3rd the diatnce in front of subject and 2/3 behind . so if subject is 10 feet away , from around 7 feet to 16 feet will be in focus
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Sorry but without lens, sensor and aperture info that is no use to anybody
Mike
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Interesting thread to read and some great advise from people 
I've been trying to self-teach myself for the last 2yrs now and still haven't got my head around shutter speed - although in fairness I've been more than happy leaving my camera to decide that and shooting on Aperture Priority...
One thing I did like was the link for the camera simulator thats been provided - definately a great resource for beginners to experiment with the different settings and see how they effect the final picture
I've been trying to self-teach myself for the last 2yrs now and still haven't got my head around shutter speed - although in fairness I've been more than happy leaving my camera to decide that and shooting on Aperture Priority...
One thing I did like was the link for the camera simulator thats been provided - definately a great resource for beginners to experiment with the different settings and see how they effect the final picture
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i would disgraee there. because in needs to be pointed out and its a common mistake that people associate DOF with distance when it isnt. its purely a scale to represent how much or little light goes into the camera. there is no defined distance as it will depend on several factors such as , as mentioned, lens, distance from subject,sensor size, hence there is no definitive answer to the ops question in regard to distance on DOF.
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Sorry, but surely DOF is not about how much light goes into the camera? Does it not instead describe how much of a given scene/image is in acceptable focus? This for a given field of view, depends on the focal length, aperture, distance to subject and sensor/frame size..
I think of exposure as being like filling a bucket.
The lens and shutter work like a tap. Open the tap wide open to let more water (light) in, the bucket fills quickly so you don't need to leave tap (shutter) open very long.
Close down the tap, less water (light) flows in, the bucket fills up more slowly so the tap needs to be open longer.
Changing ISO is like changing the size of the bucket. High ISO is a small bucket that fills up more quickly, but has less water (information), Low ISO is a large bucket that fills more slowly, but has more water.
This is a bit crude, but works for me...
2cents..
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DOF and aperture are not the same thing (although they have a relationship). DOF is very much associated with distance to the subject. DOF is a product of aperture and distance.
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Dean that's utter gibberish, but not the only gibberish in this thread!
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Oh dear, photography 101 if we keep the same aperture, focal length and sensor size then the DOF is proportional to subject to camera distance - all 4 factors affect the DOF
Mike
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I'll start from scratch because this is one if those weird threads full of misinformation.
You're getting confused because you're expecting to see a 'settings' instruction, but none exist. That's because in photography 'settings' aren't the simple instructions new photographers expect. They're a bunch of variables to consider when trying to create an image.
Depth of field is a complex calculation (have a play with a DoF calculator), but a fairly simple principle:
In simple terms, a larger aperture (small number) has a shallower DoF, a small aperture (large number) has a deeper DoF. So the more you need in focus, the smaller aperture you'd use.
As you can see in the posts above, there are complications to that, but as you should also see, even some quite talented photographers don't really understand it properly. So, perfect technical knowledge isn't that important. The joy of forums is that all 'opinions' are seen as equal, and it takes a forum expert, rather than a photography expert to be able to cut through the crap.
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Oh, brilliant. That and some experimentation should help me out no end! Cheers.
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The best explanation that I read about DOF was in an ebook sold by Amazon.
According to the author - High shutter speeds do not allow the light which is far from the camera time enough to focus properly
Fortunately the ebook was a freebie when I downloaded it but it still cost me time reading some of the rubbish.
According to the author - High shutter speeds do not allow the light which is far from the camera time enough to focus properly
Fortunately the ebook was a freebie when I downloaded it but it still cost me time reading some of the rubbish.
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what you mean like your comment.. not only pointless but utterly useless.. typical forum troll comment .
and DOF is controlled directly by Aperture . wide aperture, shallow dof, narrow aperture deep DoF. however you look at it , DO is still measure as an indefinable distance and aperture purely a scale of which to base that on but as i stated the simple rule of thumb is 1 3rd in front and 2 3rds behind the subject matter which in simple base math is a scale and not a unit of distance
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I struggled for ages with this and then I got a tip.
Ask yourself, "Do I set shutter speed or depth of field"? One will be more important than the other.
The one you pick will be relevent to your subject, Then you can adjust the other to suit.
Have the ISO set to auto until you get to grips with SS and F'no's then introduce yourself to ISO.
Finally the penny drops
Ask yourself, "Do I set shutter speed or depth of field"? One will be more important than the other.
The one you pick will be relevent to your subject, Then you can adjust the other to suit.
Have the ISO set to auto until you get to grips with SS and F'no's then introduce yourself to ISO.
Finally the penny drops
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The effects aren't always easy to see on a small viewfinder so don't worry too much about that. As Phil V says, essentially the smaller the number the less will be in focus, the larger the number the more will be in focus.
Take this example at f/2.8 on a 50mm lens. Notice how the background's very blurred? That's because the large aperture has created a shallow depth of field so pretty much whatever you focus on will be the only thing in focus assuming everything behind it is quite a long way away.
If we make the aperture smaller (called stopping down) to f/8, we can see the background is starting to become a bit clearer as the depth of field increases.
Stopping down further to f/16 we're starting to pull the background into focus even more. There's quite a distance here between the bottle and the other side of the street, if the bottle were a few feet further forwards and I focussed on it there the entire scene would probably be sharp.
Another thing that affects depth of field is focal length. Basically the lower the focal length the greater the depth of field will be, the more you zoom in (the longer focal length you use) the shallower the depth of field will be.
Here's 24mm at f/8, the background is roughly as in focus as it was at f/16 on a 50mm lens:
If we try f/8 at 200mm we see a completely different depth of field with the background being almost completely blurred:
All these things can be used purposely to affect how your images look. If you're shooting in the street and want the entire scene in focus and sharp, try using a wide angle lens and stopping down to something like f/11. If you're taking a portrait of someone and want to heavily blur the background, try something like a 200mm lens with an aperture of f/4.
All this seems like a lot of info to take in - and it is - but it does come in time. In some cases it comes without you even trying, you'll just be out one day with your camera and it'll all click into place. Try not to let it frustrate you, just enjoy taking photos.
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strangely you say in a second that it is affected by distance from subject, so which is it? Depth of field IS associated with distance
sorry but DOF has nothing to do with lighting levels, although lighting levels may dictate for example what apertures are available and hence possible DOF
Mike
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Well that's a good way to remember that the larger the f no. the more you will have in focus, but in fact the f no. is a mathematical expression where f no. = focal length of the lens/the effective diameter of the lens.
So if you have a lens of FL=300mm and the effective diameter is 20mm then the f no=f15, and if it is 40mm then the f no = 7.5
Obviously these are not the usual f nos quoted but they are used to illustrate the principle.
The effective diameter is of course the iris of the lens which on a DSLR is controlled by the electronic system of the camera.
More difficult to understand is how the f nos change ie 2.8, 4, 5.6, 8 etc and how the progression changes the light transmitted to the sensor (or the film) by a half if going from say, f8 to f11 and doubles it if going the other way.
That is to do with the area of the hole which the iris creates and rather than go into the maths of it suffice to say that a hole corresponding to say f2.8 lets through twice the light of a hole corresponding to f4 and 4 times the light of a hole corresponding to f5.6
Which is why they are always aligned that way so when looking at those numbers just remember that regardless of the lens focal length the f no. will always let through the same amount of light whatever lens it applies to.
So whether you have a 50mm lens, a 75mm lens, a 128mm lens - f11 lets through the same amount of light on any and all of them as do all the other f nos.
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Don't know about anyone else but I've just found this amazingly useful, thank you!The effects aren't always easy to see on a small viewfinder so don't worry too much about that. As Phil V says, essentially the smaller the number the less will be in focus, the larger the number the more will be in focus.
Take this example at f/2.8 on a 50mm lens. Notice how the background's very blurred? That's because the large aperture has created a shallow depth of field so pretty much whatever you focus on will be the only thing in focus assuming everything behind it is quite a long way away.
If we make the aperture smaller (called stopping down) to f/8, we can see the background is starting to become a bit clearer as the depth of field increases.
Stopping down further to f/16 we're starting to pull the background into focus even more. There's quite a distance here between the bottle and the other side of the street, if the bottle were a few feet further forwards and I focussed on it there the entire scene would probably be sharp.
Another thing that affects depth of field is focal length. Basically the lower the focal length the greater the depth of field will be, the more you zoom in (the longer focal length you use) the shallower the depth of field will be.
Here's 24mm at f/8, the background is roughly as in focus as it was at f/16 on a 50mm lens:
If we try f/8 at 200mm we see a completely different depth of field with the background being almost completely blurred:
All these things can be used purposely to affect how your images look. If you're shooting in the street and want the entire scene in focus and sharp, try using a wide angle lens and stopping down to something like f/11. If you're taking a portrait of someone and want to heavily blur the background, try something like a 200mm lens with an aperture of f/4.
All this seems like a lot of info to take in - and it is - but it does come in time. In some cases it comes without you even trying, you'll just be out one day with your camera and it'll all click into place. Try not to let it frustrate you, just enjoy taking photos.
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Brilliant examples that have made this subject very easy to understand for a relative newcomer.
The effects aren't always easy to see on a small viewfinder so don't worry too much about that. As Phil V says, essentially the smaller the number the less will be in focus, the larger the number the more will be in focus.
Take this example at f/2.8 on a 50mm lens. Notice how the background's very blurred? That's because the large aperture has created a shallow depth of field so pretty much whatever you focus on will be the only thing in focus assuming everything behind it is quite a long way away.
If we make the aperture smaller (called stopping down) to f/8, we can see the background is starting to become a bit clearer as the depth of field increases.
Stopping down further to f/16 we're starting to pull the background into focus even more. There's quite a distance here between the bottle and the other side of the street, if the bottle were a few feet further forwards and I focussed on it there the entire scene would probably be sharp.
Another thing that affects depth of field is focal length. Basically the lower the focal length the greater the depth of field will be, the more you zoom in (the longer focal length you use) the shallower the depth of field will be.
Here's 24mm at f/8, the background is roughly as in focus as it was at f/16 on a 50mm lens:
If we try f/8 at 200mm we see a completely different depth of field with the background being almost completely blurred:
All these things can be used purposely to affect how your images look. If you're shooting in the street and want the entire scene in focus and sharp, try using a wide angle lens and stopping down to something like f/11. If you're taking a portrait of someone and want to heavily blur the background, try something like a 200mm lens with an aperture of f/4.
All this seems like a lot of info to take in - and it is - but it does come in time. In some cases it comes without you even trying, you'll just be out one day with your camera and it'll all click into place. Try not to let it frustrate you, just enjoy taking photos.
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Having grasped the principle may I ask why it actually happens when essentially the picture is taken through the same piece of glass albeit different parts of it.
hashcake
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There is absolutley nothing wrong with using those 2 modes, not everyone uses full manual mode and those 2 allow you to take control of what I consider a priority.
Personally I found that playing with these 2 modes gave me a much better understanding of the releationshio between shuffer speeds and aperture.
You've been given some really good advice and I have nothing to add to it but I will say that you have some very good photos on flickr and I can see with you progress that you have learned quite a lot so keep at it
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Tringa
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There is a belief among some that manual mode is the Holy Grail of exposing a shot. I think this belief is held more by some who are learning and think good/proper/professional photographers always use manual because it is better.
Good/proper/professional photographers use whatever mode is most appropriate to achieve the result they want, not because it is, in absolute terms, a better mode.
Sometimes manual is the best way of getting what you want, but at other times AV or Tv will be the most appropriate.
Dave
Good/proper/professional photographers use whatever mode is most appropriate to achieve the result they want, not because it is, in absolute terms, a better mode.
Sometimes manual is the best way of getting what you want, but at other times AV or Tv will be the most appropriate.
Dave