Nikon D300 focusing question

<p>Thank you in advance for any help. When I am shooting with my D300, how do I get everything in focus ? For example, if I am shooting stationary subjects, I use single focus point AF and single servo AF, but if there are too many subjects in the exposure, like a group of people, where should I aim my focus point to keep everybody in focus? Does this have to do with DOF and the aperture used ? Does this has to do with how many focus points are used in the AF-AREA mode ( 9, 21, 51, etc ) ? I have notice that for example when shooting flowers and my camera is set to single focus point AF and single servo AF, only the area where I am aiming my focus point is in focus but not the rest, is this normal or not ? Is it because I am using only 9 focus points or not ? If I am shooting a group of people that are not in the same focal plane, where should I aim my focus point to keep everybody in focus ? Is there any rule to follow as there are exposure rules as the sunny 16 rules for example ( that by the way I am familiar with and I use them in every single shot ) ? Does this have to do with AE-L or not ? Please help and thank you again for all of your help guys. You are the best and have a happy shooting.</p><div></div>

<p>Focus on an object in the middel, not in the middel of the pic but in distance, and use a very small aperture or focus manual on the hyperfocaldistance and everything from a 'certain' distance till oo is sharp. Certain is a function of your focal length and aperture. See DOF-master.</p>

<p>Maurice, the number of focus points you use has no effect on what objects will be in focus. The entire problem boils down to depth of focus. So if you use single focus point on any given subject, objects behind and in front of that subject will appear sharp <strong>only if you have sufficient DOF.</strong> DOF is controlled by the lens focal length, aperture, and your distance from the subject. There is a lot of information elsewhere in this forum on DOF. You need to study and understand that subject.</p>

<p>Indeed it boils down to depth of field. To get started on getting that: <a href="http://www.dofmaster.com/dofjs.html">http://www.dofmaster.com/dofjs.html</a></p>

<p>The point is, the longer the lens, the shorter the DoF (typically). So you example picture shot at 250mm, you'd need a very very small aperture (like f/32 thereabouts) to get "everything" in focus. And at small apertures, the image quality degrades very rapidly due to diffraction. So essentially, with a long lens, you should not aspire to get "everything" in focus.</p>

<p>A very easy way to get vastly more depth of field: a digital compact camera.</p>

<p>Frankly, if you are unaware about depth of field and that it related to choice of focal length, aperture and subject distance, and not AF set-up, you may want to consider reading some good introductions to photography or take a course. The more entry-level bodies have the special modes that can help sort these things out, but the D300 is not entry-level (and in my view not the best choice of camera to learn these things with). Sorry if this sounds blunt, but your question sounds like you need to learn these photography basics.</p>

<p>OK thank guys, we'll do.</p>

<p>maurice, i agree that you have much to learn, but you have the D300 now so there's no need to worry about it -- just get busy.<br>

you may find a button on your D300 called "depth of field preview" to see how your choices of focal length and aperture will affect the image while you're composing it in the viewfinder.<br>

this button is on the front of the camera, accessible with the index finger of your right hand, if you simply extend it toward the lens.<br>

normally during focusing, the aperture is open to its maximum setting so the image in the viewfinder is a bright as possible. when you press the DOF preview, it closes the aperture down to the setting you've selected for the shot. this allows you to judge the location of the in-focus area before you release the shutter.</p>

 

<p>Thanks William, yes I must learn and there is not stop learning in life and that is why I am posting this question so I can learn from you guys and I do appreciate your help. I have used this button before but again, for example, I know that small apertures ( f/16, f/22 and f/32 ) are the best for DOF, that medium apertures like f/8 and f/11 are the best when shooting subjects on the same focal plane and getting the sharpest photos and on the other end, the large apertures f/5.6, f/4 and f/2.8 are for isolation and blurred background, also I know ( by reading the book Understanding Exposure by Bryan Peterson ) about how to apply the sunny 16 rules but the question is ... is there any formula or reference as a guide, that lead me to excel this and improve my pictures ? Just want to improve to the max because I am taking photography very seriously, not just for hobby and would like to have all the possible advises from another photographers from whose I can learn. I guess, there should be a reference point about this and that is what I need to find out, which one is it and thanks all of you for your help.</p>

<p>There are no strict rules , since the DoF is not only dependent on the aperture (but also focal length and subject distance). More importantly, it's what creativity demands. There is no substitute in this respect for shooting a lot, and getting a feel for it. Sticking to rules for this would not spark a lot of creativity, and that's why it's more important to get a feel rather than some guideline.</p>

<p>Avoid the very small apertures; on a D300 I would not go beyond f/11 since above that diffraction starts to kick in seriously and it will degrade the image quality considerably. Consider that the DX cameras have more depth-of-field (since a 35mm lens is normal, which has more DoF at an equal aperture than a 50mm will have). An average, you could add 1 stop of aperture compared to 35mm - as the "medium" apertures, I use f/5.6 and f/8, for loads of DoF f/11. Bryan Peterson's book is using the "film/FX" values.</p>

<p>Hi Maurice, people are giving you a lot of great advice but it probably looks a bit complicated. I learned a lot of this kind of stuff by taking a 12 week Basic SLR night school course. I found it a lot easier than reading books and going on forums.<br>

If you get the opportunity, a course like that can really help to unlock the possibilities of that great camera and get you closer to producing the images that you aspire to.<br>

Good luck!</p>

<p>I'd like to echo Wouter's note to not stop down more than F11 - personally I limit myself to F8.<br>

Even if at 100% if the photo is slightly out of focus or even blurry, how will you be distributing the final image? Prints? Low res files online? I was shooting the Thames Festival parade this weekend, and I had some shots I liked that were slightly out of focus. Resizing them for the web and you can't really tell they are out of focus.</p>