Help me focus properly

[Rifter]

Don't get me wrong - I use auto-focus 99% of the time. What I'm saying is if you use single-point auto-focus, you control where the camera focuses and its much more reliable than auto-area/automatic AF point selection.

I have a feeling AF will work much better when i upgrade to a FX body with more focus points, with only 11 it just feels lacking and i find it less frustrating to just focus oldschool way with your finger.

Even using focus point focusing where you manually select the point, with 11 there just isnt always a point you want to use. And i take alot of nature/animal pictures where sometimes you only have a split second to get the shot, so i tend to go with what i know will work and trust and thats my fingers.

Especially at long zoom 200mm+ moving the frame to get what you want in focus on a focus point to select it is not always easy to do at that magnification.

Just my experience, i would imagine portrait photographers would not have those issues lol.

 

[CuriousMike]

And i take alot of nature/animal pictures where sometimes you only have a split second to get the shot, so i tend to go with what i know will work and trust and thats my fingers.

Huh. That seems contrary to me... like, I'd think auto-AF would be the fastest and surest way to capture an animal. I don't have the muscle memory for MF so I'm at a disadvantage.

My D610 is notorious for too narrow of the AF focus spread. I tend to just keep the AF point in the center or one of the rule of thirds points and shoot.

 

[Red Squirrel]

You have to make sure the "square" is where you want to focus to, then anything in that general depth will be in focus. Usually I aim for an edge, as well, because if the square is in something that is not an edge the camera may have trouble auto focusing. For outside in brightness I tend to jack up the aperture because I can get away with it, and get more depth of field. Just be careful not to jack it up TOO high because any dirt on the sensor will show. My sensor is kinda dirty and I have yet to be able to clean it properly, it's very tricky to do as the dirt is microscopic and will only show up in specific settings.

 

[thestrangebrew1]

There is some awesome info in this thread. I'm heading to a family reunion in Tahoe tomorrow for the weekend and it should be a great time to practice focusing on subjects and groups!

 

[Rifter]

You have to make sure the "square" is where you want to focus to, then anything in that general depth will be in focus. Usually I aim for an edge, as well, because if the square is in something that is not an edge the camera may have trouble auto focusing. For outside in brightness I tend to jack up the aperture because I can get away with it, and get more depth of field. Just be careful not to jack it up TOO high because any dirt on the sensor will show. My sensor is kinda dirty and I have yet to be able to clean it properly, it's very tricky to do as the dirt is microscopic and will only show up in specific settings.

I do the same thing, stop it down as far as possible in great light outside to be able to have as much depth of field as possible. Makes focusing alot easier too.

 

[Rifter]

Huh. That seems contrary to me... like, I'd think auto-AF would be the fastest and surest way to capture an animal. I don't have the muscle memory for MF so I'm at a disadvantage.

My D610 is notorious for too narrow of the AF focus spread. I tend to just keep the AF point in the center or one of the rule of thirds points and shoot.

I leared to use a camera on a old no AF 35mm SLR camera, focusing with my fingers is second nature now.

If i had learned on AF i would probably be much better using it.

 

[Syborg1211]

I have a feeling AF will work much better when i upgrade to a FX body with more focus points, with only 11 it just feels lacking and i find it less frustrating to just focus oldschool way with your finger.

Problem with going bigger sensor is that the depth of field gets that much shallower, and then autofocus accuracy is absolutely critical. My D800E was pretty unreliable at focusing, and the D810 was world's better at getting critical focus at say f/2. It still missed more than I liked though, and that's when I dumped autofocus completely and went to a rangefinder system where if the focus is off it's my fault at least. My eyes are definitely not good enough to manual focus a DSLR. Anyone who does that gets my respect.

 

[thestrangebrew1]

Problem with going bigger sensor is that the depth of field gets that much shallower, and then autofocus accuracy is absolutely critical. My D800E was pretty unreliable at focusing, and the D810 was world's better at getting critical focus at say f/2. It still missed more than I liked though, and that's when I dumped autofocus completely and went to a rangefinder system where if the focus is off it's my fault at least. My eyes are definitely not good enough to manual focus a DSLR. Anyone who does that gets my respect.

I've only got 9 focus points on my t5i. You carry a range finder and do your calculations to set aperture and distance you should be at to take a pic?

 

[CuriousMike]

My eyes are definitely not good enough to manual focus a DSLR. Anyone who does that gets my respect.

My impression is that MF on a solid film-SLR was easier than it is today; is the viewfinder somehow brighter?

If focus is absolutely positively critical (and i'm using shallow DOF), LiveView can work.

 

[Syborg1211]

I've only got 9 focus points on my t5i. You carry a range finder and do your calculations to set aperture and distance you should be at to take a pic?

I use a rangefinder camera. So the rangefinder is built into the camera and is used to control the focus distance. It's got this box in the middle of the viewfinder that you line up to achieve focus. Hard to explain right now, but there's lots of good pics and information out there. It's definitely a slower process.

Film SLRs as well as even just full frame DSLRs have big, bright viewfinders. It's not impossible to manual focus them. There is just no way to know for sure if it's in focus. A rangefinder makes it more obvious when something is in focus.

 

[Rifter]

Problem with going bigger sensor is that the depth of field gets that much shallower, and then autofocus accuracy is absolutely critical. My D800E was pretty unreliable at focusing, and the D810 was world's better at getting critical focus at say f/2. It still missed more than I liked though, and that's when I dumped autofocus completely and went to a rangefinder system where if the focus is off it's my fault at least. My eyes are definitely not good enough to manual focus a DSLR. Anyone who does that gets my respect.

I find the viewfinder more than bright and clear enough to focus manually most of the time. Luckily my eyesight is perfect so far, a little worried though since everyone in my family needs glasses, lol.

 

[jhansman]

Don't get me wrong - I use auto-focus 99% of the time. What I'm saying is if you use single-point auto-focus, you control where the camera focuses and its much more reliable than auto-area/automatic AF point selection.

Amen. I never have (nor likely will) used more than a single focus point in my DSLR. Yes, it took some time to learn how to find the hyperfocal point in a composition, but I am also not opposed to taking more then one shot, focusing on different objects in the scene. Like bracketing, this ensures that one of my exposures will catch everything from front to back at f11-f16 for landscapes. For family shots like the OP's, I usually shoot with an aperture somewhere in the middle of the lens, but have gotten away with f5.6 with my 100mm for acceptable bokeh. Fun!

 

[slashbinslashbash]

Depth of Field ( how much is focused from the front of the scene to the back of the scene ) is a function of aperture and distance to the subject. ISO has no bearing on what is in focus.

For reasons I don't fully understand, smaller sensor cameras ( think smartphone ) generally have a larger depth of field ( more is in focus ) than larger sensors. Generally, it's harder for a smartphone to have out-of-focus areas of an image than a larger sensor DSLR.

Put another way, it's often difficult with a large sensor camera to have an entire scene perfectly in focus.

The reason my photo looks to be in clear focus from the rocks in front to the mountains in back is a function of the fact that the rocks are actually somwhat distant in front of me and I focused about 1/3 into the scene. If I needed more foreground in focus, I would have had to use a smaller aperture than I did.

It also has to do with focal length and sensor size.

There is a good tool here:

http://www.dofmaster.com/dofjs.html

It shows you the DOF of a setup when you choose the body, lens, focal length, focus distance, and aperture.

In general, the following things produce shallower DOF:
Bigger sensor (full frame > crop frame > m4/3 > P&S > cellphone)
Longer focal length (e.g., telephoto lenses 70mm and longer)
Shorter focus distance (e.g. < 10 feet)
Larger aperture (e.g. f/1.4)

Oppositely, the following things produce deper DOF:
Smaller sensor
Shorter focal length (i.e., wide angle)
Longer focus distance (e.g. 50 feet)
Smaller aperture (e.g. f/8, f/11)

To give two examples, an ultrawide like a 17mm on a full-frame will give practically infinite DOF when at f/8 or narrower aperture, especially when focused more than a foot or two away. A telephoto like 200mm on full-frame will give very shallow DOF when used at f/2.8 even when focused at a pretty long distance.

 

[Red Squirrel]

One thing I find that helps is to use the LCD then zoom in (digitally) as far as it will go then focus manually, you'll be able to better see if you are dialed in right. I usually do that for stars and such. I also use two tripods, it stays more steady (for big lens, as it has it's own tripod mount + camera mount). Even then, it's tricky to be 100% dead on though. It's how I took this one, but still a bit blurry.

 

[twinrider1]

What I like to do hold the shutter release to lock my focus. Using this pic, I focus on the eye with the center focus point. Then, while keeping the shutter release half depressed, I recompose and take the shot. It's faster for me than the directional pad. You do have to be in Auto Focus-Single and not AF-Continuous so it doesn't hunt.

OP, try going full manual everything and just take practice shots. Take the same shot at every f-stop. You'll learn a lot.

 

[thestrangebrew1]

I practiced a little while I was out of town but I didn't have as much time as to go out as I thought I would.

I did learn how to do some silhouette shots during the sunset on saturday night.

 

[slashbinslashbash]

What I like to do hold the shutter release to lock my focus. Using this pic, I focus on the eye with the center focus point. Then, while keeping the shutter release half depressed, I recompose and take the shot. It's faster for me than the directional pad. You do have to be in Auto Focus-Single and not AF-Continuous so it doesn't hunt.

OP, try going full manual everything and just take practice shots. Take the same shot at every f-stop. You'll learn a lot.

You have to be careful with that technique, especially with very narrow DOF like you might have with, say a 50mm f/1.4 or 85mm f/1.8 at their widest aperture. At 6 feet, the 85mm f/1.8 has a total DOF of about 2 inches. The eye is already set back in most people's faces a bit, and the way the angles work, if you put the center point on the eye, lock focus and then re-compose, often the focus point ends up even further back in the face (almost back by the ears). This can put the tip of the nose well out of focus, and in some cases even the mouth or eyebrows. Of course this depends on the angle of the head relative to the camera, but I have seen it happen a million times.

In portrait photography where you can take your time with a shot, go ahead and choose the proper focus point instead of using the center point and re-composing. It makes a big difference when you have shallow DOF!

 

[jhansman]

In portrait photography where you can take your time with a shot, go ahead and choose the proper focus point instead of using the center point and re-composing. It makes a big difference when you have shallow DOF!

Agreed. Since the eyes are your focal point (traditionally), make sure one of your points is on them and red; everything else is gravy. BTW, that moon shot is cool!

 

[twinrider1]

You have to be careful with that technique, especially with very narrow DOF like you might have with, say a 50mm f/1.4 or 85mm f/1.8 at their widest aperture. At 6 feet, the 85mm f/1.8 has a total DOF of about 2 inches. The eye is already set back in most people's faces a bit, and the way the angles work, if you put the center point on the eye, lock focus and then re-compose, often the focus point ends up even further back in the face (almost back by the ears). This can put the tip of the nose well out of focus, and in some cases even the mouth or eyebrows. Of course this depends on the angle of the head relative to the camera, but I have seen it happen a million times.

In portrait photography where you can take your time with a shot, go ahead and choose the proper focus point instead of using the center point and re-composing. It makes a big difference when you have shallow DOF!

Yep, yep, I keep the f-stop in mind. I'm just hard headed too. Stuck in my film camera ways and I'm not comfortable using the round multi-selector when I have the camera up to my eye. I do love digital though. Immediate feedback, unlimited shots at zero cost. Can't beat it.