Getting Sharper Photos!

January 11, 2017  •  Leave a Comment

Getting Sharp Images 101

Hello, everyone and welcome to Philip Hegel Photography!  I think of all the other blogs, Facebook groups (like Emily's, where you may have come from) and reddit groups about photography that I belong to the question that I see come up the most is "my photos aren't very sharp, should I buy a new camera?".  Short answer, no.  I am sorry to have to tell you, but it's probably you, not your gear.  I love this question though because having tack sharp photos is so important to delivering a quality photo, especially for larger prints. Whether you are brand new as a hobbyist and just got your first dSLR or you have been shooting for a while now, but just started learning about sharpness, this post can get you started. Can most photos get away without being sharp?  Maybe, but that isn't a world I want to live in, so read on for some quick tips about improving the sharpness of your photographs!

We are going to cover some of the most common things here:

-How you focus (choosing your focal point and back button focus)

-Aperture

-Light

Choosing Your Focus Points

The first place that I think a lot of photographers start off wrong is with the autofocus functions.  Do professionals use autofocus?  Absolutely, but really only one function of it and that is trusting the camera to ensure we are focused on the finest detail the lens will allow.   If we manually focused all of the time we would miss so many great shots because it just takes more time and we are always looking for smart ways to work faster.  Cameras these days are capable of such amazing things, and one of them is lightning fast focus speeds on AF.  However, you still need to be the one telling the camera where to focus.  

Do you press the shutter button down halfway and see quite a few little boxes light up in the view finder automatically?  If you currently rely on your camera to pick the focus points for you, this is the number reason why you aren't getting consistently sharp photos.   I prefer, and recommend going with single point as shown in the (attempted) photo of the view finder.

As I said, these cameras are smart, but when it comes to focus it can only guess where you think the subject of the photo is.  The camera is not going to guess right enough of the time to make this time saver worthwhile, unlike allowing the camera to focus sharp on the one spot you select.  Myself, I always choose my own focus point, and I keep my AF on "Single Point" (Nikon) which means just one box in the view finder, that you move around to where you want the center of focus to be (but I typically keep it in the middle, and then "focus and recompose", which is a technique I will briefly discuss below but go into detail in another post).  Look in your camera manual or on google to see how to set your camera up this way.  This will allow you to choose specific focus points and to highlight that focus on smaller details.  Instead of focusing on an entire head, you can focus on the eye, or the bridge of the nose and let some of that focal plane naturally fall a little bit forward and a little bit backward from the center, and that is how you start getting those tack sharp images with all of the detail you have been looking for.  Now there are times you may wish to use other focus points, or things like 3D tracking for objects in motion, but for simplicity this post covers mostly stationary subjects.  

 

 
For steps on how to setup your camera properly, here are some great videos on YouTube for Nikon, and here are some for Canon.  This brings us to the next topic of how I focus once I have chosen that single spot, and it is not with the shutter button..
.

Back Button Focus

Your camera straight out of the box is setup to be started quick and used fast.  Often eager photogs jump in so quickly they neglect many of the things the camera can do outside of factory default settings, and the custom menus are probably some of the neatest features of your camera!  You can change the way the camera works, what buttons do what and when, to better fit your hands, your style, whatever you prefer.  One of the easiest changes you can make that might actually affect the sharpness of your photographs is to activate the "back button focus" function.  

To be clear, this isn't a magical "instant sharp button", it is just a different way to focus the lens that many-myself included-find not only ergonomically easier, but less prone to losing focus once obtained through accidental pressure on the shutter button (or worse, accidentally taking the picture by pressing the shutter button before focus was obtained).  

By moving the focus function off the shutter button to a button you operate with your right thumb on the back of the camera (typically the AE-L/AF-L button) you make the shutter button one function: opening the shutter to take a photo.  The pressing halfway down will no longer activate focus, you do it manually with the back button and your thumb.  This way, you can "lock" the focus once you have it by lifting your thumb (or focus continuously by holding it down for moving subjects), and when you are ready you press the shutter button down.  Your camera has a little icon on the viewfinder, it may beep, or the focus boxes may turn green to tell you when it has achieved focus. As long as the distance from the lens to the subject doesn't change after lifting off the back button, neither does your focus from where you left it last.  So you can focus on a stationary object like a models eye, then readjust your camera settings or even the composition of the photo if you need to, and the focus is still locked on the same distance as the subjects eye.  Note that if you move up or down or side to side too far and change the distance from your lens to your subject then your focus point will also move to a different spot.  This can be bad, but it can also be how you "focus and recompose", which I mentioned earlier.  This is why I use just one focus point in the center, because it is usually your best and sharpest focal point.  

 

Lets say I want to focus on the models eye but I want her in the corner of the photograph, but my focal point is in the middle.  So I point that focal point in the middle at her eye, then I "recompose" the frame of the photo to move the model where I want her in the composition, being very careful to maintain the same distance from the end of my lens to the model.  Focus and recompose is a great technique that I will cover in another post with more detail, but look it up on your own once you get comfortable with back button focusing! 

 

For instructional videos on how to set up back button focus for Nikon you can start here, for Canon you can start here.  So far we have been pretty non-technical, but the next part will discuss a few technical terms that you need to know, so if you don't, this post won't teach you but I suggest you spend a moment to look them up before you move on.

Aperture 

So you just bought that new 50mm f/1.8 prime lens because you saw that gorgeous bokeh (blurry background) everyone gets shooting with those, then the first time you used it you got that blur, but the photos were not sharp at all.  What's up with that?  Well let me tell you what you (and many others before and after you) probably did wrong: you stopped up too far (made your f/stop number too low).  The solutions to this are simple to understand, though.  The f/stop (aperture) controls not only how much light comes in the lens by opening or closing the aperture blades in your lens but it also determines how deep or shallow your focal plane is.  You need to find that sweet spot on your lens where the f/stop provides you with enough Depth of Field (DoF) to maintain sharpness where you want it, while blurring out the things you don't want so that your subject stands out, giving it that more professional look you desire.  Refer to the first photo on this post for a great example of using bokeh combined with sharpness to really make your model stand out!  One of the first rules of portrait photography is unless you need to let in the extra light (shooting in a church that doesn't allow flash photography might be an example), very rarely will you stop all the way up to f/1.8 (or f/1.4).  Most lenses have that sweet spot about 3-5 stops from being all the way open at the lowest aperture.  For many f/1.8 (or f/1.4) lenses this means shooting at f/2.5-f/3.5.  The next rule to remember is that the opposite also applies, if you continue to stop down too far to say f/10-f/16 then you will start to see your focus fall off again, just as it did when you stopped up to f/1.8 because you are too far off that sweet spot.  Why does this happen?  Well first it is because the aperture sets how "deep" your focal plane is (I will do another post about focal plane alone and link back to it when it is up, but for now google is your friend).  So the smaller the aperture number (which is actually a larger f/stop because like all things in photography we do this a little backwards) the less depth to that focal plane.  So much so that with a 50mm lens at f/1.8 with the subject standing five feet in front of the lens the DoF is only around 3.5 inches deep, total.  That means of the entire picture, only three and a half little inches of the subject will be perfectly focused.  Some of that focus naturally will fall in front of the focal point and some behind, so that means if you are focused on an eye you might not have the nose (or the other eye if the subject is turned to a profile pose) in focus because your focal plane is only about 1.5 inches on either side of the focus point, and a nose is longer than 1.5 inches (see examples).

 

 

 

 
 

 

 

 

 

 

 

The photo on the left (top on mobile) was shot at wide open, (f/1.8) notice how the focus starts to drop off so quickly that the tip of the nose and her hair are out of the focal plane and very soft compared to directly underneath the eye on the left (her right).  The right photo (bottom on mobile) was shot with by stopping down the aperture to f/4.5 and decreasing the shutter speed to allow the same amount of light in.  Notice now the entire face and all of the detail is in focus, not just under the eye, and even her hair is in better focus from front to back.  The bigger focal plane increased our Depth of Field allowing for more of the head to be sharp.
  

 

 

 

Some ways to increase the DoF are to increase the number of the f/stop as mentioned, or stand further from your subject.  But if you stand too far, then you will lose that blurry background you might have wanted.  The easiest way (not always the best but for general purposes this is good) to get sharp faces with blurred backgrounds is to stop down to say f/2.8, place your subject five to ten feet in front of the lens, and the background as far from the subject as possible.  There are TONS of great, free apps for Android and Apple you can download to reference until you start to get the feel.  Now if you have done all of this but you still can't get those tack sharp photos, the last thing to look at is how much light you have in your scene and how you are capturing that light, which we will cover next.

Light

Photography is all about light, in fact it is in the name photography which has it's roots in Greek, where photo means light!  You are capturing photons of light that you see in the scene on an electronic sensor, and you have many ways to let that light in such as your aperture (previously discussed), ISO (increasing the gain electronically on the digital sensor), and shutter speed.  Your shutter speed determines how long the shutter is "open" and letting light fall onto the sensor.  How does this affect sharpness?  Well, bad light will not be able to give you the details you are looking for.  Whether that is too little light, or too much, you will lose sharpness.  The number one way shutter speed affects your sharpness is because you are shooting at too slow of a speed to handhold the camera, and you are getting camera shake in your picture which throws off focus.  The standard rule for handheld photography of 1/focal length is your absolute minimum for shooting without the assistance of a tripod or something else stabilizing.  So using our earlier example of a 50mm prime lens, you should never shoot slower than 1/50th of a second.  If you are shooting with a 70-200mm zoom at 200mm, then you should never shoot less than 1/200th, and so on.  Vibration reduction on your lens can get you to break that rule by up to four stops of slower shutter speed, but don't rely on that, stick to the rule.  Many photographers actually establish a blanket rule of never shooting below 1/250 or 1/400 no matter what lens they use.  So always make sure if you cannot use a tripod that you keep your shutter speed fast enough to ensure no camera shake causing the focus to be lost.  

Leaving after a shoot in the city, this was taken in extremely low light but I was able to take advantage of the available ambient light reflecting off a white washed wall just behind me that reflected perfectly on to her face giving enough light to keep the aperture at f/2.5 to maintain sharpness, even with dead batteries in the flash.

As mentioned before, bad light will prevent sharpness for many reasons like poor capture of details, and causing you to shoot at too slow of a shutter speed.  So how do you overcome this if you cannot open the aperture wider or shoot at a slower shutter speed?  Well, depending on your camera you may be able to just bump the ISO up to increase the signal gain on the sensor, but if you don't have a great sensor capable of shooting at high ISO you will end up with lots of digital noise on your photo.  Odds are that you are the only one who will notice the noise, not your client, but it still bothers us and makes us crazy as artists to see that on our work.  So now you are left with trying to get as much actual light on your subject as you can.  You can move the subject into better light which isn't always an option, use reflectors to move light around the area onto your subject, or use external light such as flash/strobe or continuous studio lighting, but that is a whole other subject we will discuss at a later date.  

In conclusion, remember that you are always trying to capture light in your photography and there are many ways to capture it.  The better the light hitting your sensor, the better the details you will capture.  The better the details, the sharper the photo is, and the better it looks.  Whether it is your focal points being on the wrong part of the light (subject), your aperture not giving you a deep enough focal plane, or your shutter speed causing camera shake these are all fixable issues.  Remember that the odds are best that it is NOT your camera, it is NOT your lens, it is you (sorry!), but that means you can fix sharpness issues without spending money and only spending time to practice!  Happy shooting, and good luck!  Feel free to leave comments or email me at [email protected] if you have any questions and thank you for your time!  -phil-

www.phegelphoto.com

 


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