For this week’s episode, I’m releasing a new tutorial for our Photographer’s Friend Depth of Field calculator, and I’ve included some practical examples from the field so this may be useful as a general tutorial, even if you don’t own Photographer’s Friend.
I was actually going to just release this video in the background, but with a bunch of stuff that came up and the fact that it’s supposed to be a holiday in Japan today, I decided to make this it for this week. If you are completely uninterested in our iOS app and have no interest in Depth of Field, I have a nice meaty episode lined up for you next week, so please stay tuned.
If you are interested in the new tutorial though, I’ve embedded it below, and you can also find it on our Photographer’s Friend Tutorials page. Also, a quick shout out to listener Ron Paynter in Australia, with a thank you for pointing out that I had a typo in the Startup Help for the Exposure Shift calculator. I can’t believe I missed out the “f” in Shift, but thanks for bringing some laughter to our breakfast table yesterday morning Ron.
I was actually working on a minor update to the app anyway, so the typo has been fixed in version 3.0.4 which is already on the App Store ready for people to upgrade. Anyway, here is the video, which I hope you enjoy, and I’ll be back with another episode next week.
This week we’re going to take a look at Exposure Value or EV, and I’ll explain what it is, why it’s useful, and why I’ve spent almost every waking minute for the last 17 days building a new Exposure Shift Calculator for our Photographer’s Friend app, which we’ll use for some of my explanations.
When we talk about exposure, we generally use aperture, shutter speed, and ISO settings to relay the absolute values of our exposure, but then if you want to change one of the values while maintaining the same exposure, you have to change one or both of the other settings in the opposite direction. For example, if you are using an aperture of f/8, with a shutter speed of 1/250 of a second, at ISO 200, and I recommend that you change your aperture to f/11, which is one stop smaller than f/8, and therefore lets in half the light, you would need to adjust the other settings to counter that change.
You might change your shutter speed from 1/250 of a second to 1/125, which is twice as long, and therefore lets in twice as much light, so you maintain the same exposure. If though, for example, 1/125 of a second might be too slow and you don’t want to risk your subject moving during the exposure, making them blurry, you might decide to increase your ISO from 200 to 400, which makes it twice as sensitive, and brings your exposure back in line.
This can get a little bit confusing, especially if for example, you don’t want to change your aperture from f/8, because it provides just the right amount of depth of field for the photograph you are making, you then have to think about how you could make the same change with the other settings. If you are happy with your shutter speed, you could of course just change your ISO from 200 to 100, making it one stop less sensitive, and you’d have the same exposure as you would if you’d changed your aperture from f/8 to f/11.
Although people sometimes refer to the changes made to exposure as steps, it’s more common to use the term “stop”. Before we go on, although this is pretty basic photography theory, let’s just recap that by aperture stops from say f/1.0 counting in full stops would go from f/1.0 through f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16 and higher. Depending on how you have your camera set up you might have half stops between these, but generally, most cameras and light meters use third stops, so for example, between f/5.6 and f/8 you will have f/6.3 and f/7.1, though this varies slightly sometimes with different manufacturers. It’s also worth noting that the smaller the number, the larger the aperture, so a lens set to f/5.6 lets in twice as much light as when it’s set to f/8, and f/11 lets in half as much light as f/8.
Stops in shutter speed terms are calculated by doubling or halving the time. For example, if your shutter speed is 1/250 of a second, making it one stop slower would be 1/125 of a second, and that is also one stop lighter because the light hits the sensor for twice as long. Making 1/250 of a second one stop faster takes it to 1/500 of a second, which is also one stop darker because the shutter is open half the time. This continues even when we’re doing long exposures of more than a second. One stop longer than 5 seconds is of course 10 seconds, and 20 seconds is one stop longer again.
ISO stops can be a bit confusing again, but similar to shutter speeds, you just keep doubling or halving the value for each stop. ISO 200 is one stop more sensitive or brighter than ISO 100. ISO 400 is one stop brighter than 200, and two stops brighter than 100. If we keep going, we’ll work through ISOs 800, 1600, 3200 and 6400 etc. The thing to be careful with of course is that very high ISOs can start to introduce noise or grain to your images, but I’ll regularly shoot at ISO 5000 or 6400 if necessary to get the shot. It comes down to testing your camera to see how much noise is introduced in various conditions and how comfortable you are with it.
Exposure Value Stops
So, following that recap, let’s talk about Exposure Values, which are also referred to as stops, but they can be more useful because when you refer to exposure in EV or Exposure Values, it’s not tied to any one setting. According to Wikipedia, the Exposure Value system was invented in the 1950s and uses a relatively simple formula to calculate a value that can be used to represent any combination of our camera settings.
The EV scale can also be mapped to various lighting conditions, for example, if you’ve heard of the “Sunny Sixteen” rule, which is a basic guideline to set your camera aperture to f/16 and use your ISO as the shutter speed, so at ISO 100, you’d set your shutter speed to either 1/100 or 1/125 of a second. This will get you a relatively good exposure on a sunny day, hence the name, sunny sixteen.
Well, on the EV scale, the sunny sixteen rule equates to 15 EV. On a slightly overcast day, you might open up your aperture from f/16 to f/11, one-stop wider, and this would mean you were shooting at 14 EV. For an overcast day, you might go to f/8, another stop wider, and that is EV 13. Conversely, you might increase your ISO from 100 to 200 for a slightly overcast day or from 200 to 400 for an overcast day, and of course, you could change your shutter speed, but if you have an Exposure Value to work to, it’s pretty easy to recalculate your settings.
If we keep going back, the zero base for our scale can be represented as an aperture of f/1.0 for one second at ISO 100. This is EV o (zero). We can go darker, using negative numbers. For example, on the EV scale we have the Aurora Borealis at between -3 and -6 EV, and the Milky Way and Galactic Core at between -11 and -9 EV. I actually found these old values to be a little bit too dark if I compare them to my own images, such as for example, the settings I used for this photograph of the Galactic Core that I shot on my Namibia Tour this year.
I shot this at f/1.4 which is one EV more than f/1.0, putting me at EV 1. I was using a shutter speed of 5 seconds, so to continue with our mental arithmetic to see how this changes our Exposure Value number, first I double the exposure from one second to two, which takes the EV back to zero, then double the exposure again to four seconds, which takes us to -1 EV. Another second to 5 is one-third of a full stop, so that takes our EV to -1 ⅓.
I also changed my ISO from 100 to 3200, so let’s see how this affects the Exposure Value. First, changing from ISO 100 to 200 makes my sensor twice as sensitive, so my Exposure Value goes up by one stop to -0 ⅓. Doubling the ISO again to 400 is another stop, so we’re back into positive numbers with 0 ⅔. 400 to 800 ISO gives us 1 ⅔ EV and 800 to 1600 is 2 ⅔ EV, then finally 1600 t0 3200 is 3 ⅔ EV.
EV Increases as ISO Increases
You might have noticed there that calculating ISO changes can be a bit confusing. For me at least, it seems as though the scale is going the wrong way, but because the EV represents our cameras ability to capture an exposure based on how sensitive the film is, the Exposure Value goes up as we make the sensor more sensitive. Before I started to really look into how to calculate Exposure Value, I would certainly have guessed the opposite way, so this has taken some getting used to.
I guess it’s easier to think of EV as the target, as in the Exposure Value of the subject, not the base, which is the settings on the camera. For example, I’ve just used a Light Meter to take an incident reading of the light on this very slightly hazy summer’s day in Tokyo, and my reading was EV 14 ⅓. We can actually adjust the sunny sixteen rule to understand that I’d get a good exposure at the moment by reducing my exposure by two-thirds of a stop from 1/125 of a second to 1/80 of a second at f/16. We’ll come back to some more examples that will make this clearer, but for now, let’s talk a little more about why using the absolute values of aperture and shutter speed etc. isn’t ideal.
When we’re shooting on my Japan Winter Wildlife tours, we are generally using Manual Exposure, to ensure that our subjects stay well exposed whether they are over a white snowy background or a darker background like trees or the sky. This works great when the light is constant, but if there are patchy clouds, we have to change our settings quite regularly, so I shout out that I’m changing my settings to the group.
If I simply shout out that I’m increasing my exposure by one stop, which is the same as saying I’m increasing my exposure by one EV, someone will invariably ask for actual settings in aperture, shutter speed, and ISO form. Then, if for example, I say f/11 for 1/1000 of a second at ISO 800, I often get asked, what would that be if I’m at ISO 400, or what if I’m at f/8, and it’s understandable because this can be a bit confusing.
Exposure Shift Calculator
To help with this kind of exposure shift, I received an idea from listener Steve Jarrel last year, for me to add a third calculator to our Photographer’s Friend app for iOS. The implementation I’ve come up with is slightly different, but the idea is basically the same, so I’ve just this morning finished some very complicated development to create a third calculator called the Exposure Shift Calculator. This has taken so much extra work, and is such a big change that I’m actually going to make this a paid upgrade to a new version of our app, but I’m currently looking into a way to provide a pseudo upgrade price for current version 2 owners, and more details of that will follow over the next week or so.
Today though, I wanted to introduce you to the new calculator to help shed a little more light on this discussion about Exposure Values. Because Exposure Values are at the core of all exposure calculations, it is at the core of my new Exposure Shift Calculator. Here’s a screenshot from an iPad Air, showing the calculator set at zero EV, which as I mentioned is the value you get with an aperture of f/1.0 for one second with ISO 100 (below).
When you first start using the calculator, you can of course dial in any combination of camera settings, but we’ll work from EV zero, for now, to show you how this works. If you want to store your original settings for later reference, just tap the large Store Current Settings button in the middle of the screen, and your settings will be displayed there until you tap the settings again, which clears them and brings back the Store Current Settings button.
I might, for example, use the calculator to find some settings to give me a good exposure at 14 ⅓ EV on this sunny day in Tokyo, and as we can see if I select an aperture of f/5.6, and leave my ISO at 100, I would need to set my shutter speed to 1/640 of a second. In this next screenshot (below) I’ve stored my EV zero settings for reference, and dialed in my new settings so that you can see how the store function works.
There are two ways to experiment with your settings after this though, starting with locking a single dial. If you tap the Aperture, Shutter or ISO dial labels, that label turns into my teal blue color and the padlock shows that it is locked, and now when you turn one of the unlocked dials, the other unlocked dial will automatically update to a value that maintains the same exposure. I’ve locked the original settings in the middle of the screen for reference, and then locked the ISO dial, which would be useful say if you were shooting with film and literally could not change the ISO until the end of the roll, or for example if your ISO was already very high and you don’t want it to go any higher.
I decided that I wanted to change my aperture to f/14, my go-to aperture for most of my landscape work, and you can see that the calculator automatically calculated that I would need to change my shutter speed to 1/100 of a second to maintain my Exposure Value of 14 ⅓. I can of course then tap the aperture dial to lock that at f/14, and if I change the shutter speed dial, it will give me a new ISO to use, to maintain the same exposure. Note though, that when you lock an individual dial that enables the ISO value to be recalculated, the EV will change, because increasing the sensitivity of the ISO increases your EV, so the other unlocked dial has to move in the opposite direction to maintain the exposure.
That concept led me to what turned out to be the most difficult feature to code, the Exposure Value Lock. If you tap on the Exposure Value number or the padlock to its right, any individually locked dials will be unlocked, but now when you spin any dial, the other two dials will automatically update to maintain the same Exposure Value. This was particularly difficult because not only did I have to calculate two other dials simultaneously, the ISO dial has to turn in reverse to maintain the Exposure Value.
For example, if I lock the aperture dial at f/14 and change the shutter speed from 1/100 of second to a 1/200 of a second, the ISO would change from 100 to 200, to counter the shutter speed change to maintain the same exposure, but because increasing the shutter speed increases the EV by one stop and making the ISO more sensitive also increases the Exposure Value, my EV changes from 14 ⅓ to 16 ⅓.
Exposure Value Lock
So, to lock the EV, I actually have to rotate the ISO dial in the opposite direction to ensure that the Exposure Value is maintained, rather than the Exposure. I know that sounds weird, but that’s what this took to achieve and actually provide a useful EV Lock feature. If for example I have a meter reading of 16 ⅓ wanted to EV, and I wanted to open up my aperture to f/2.8 for some nice shallow depth of field, by locking the EV and selecting f/2.8 on the aperture dial, the calculator gives me a shutter speed of 1/1000 of a second at ISO of 1000.
That’s useful to see your options while maintaining the EV, but in this case, if you know that you want an aperture of f/2.8 and because you know that you have plenty of light, rather than locking the EV and going fully automatic, it would be better to simply lock the ISO and move your aperture dial to f/2.8 and then you’ll get your new shutter speed of 1/5000 of a second, for a great outdoor exposure on a theoretically very bright sunny day.
Send To Buttons
If, for example, you don’t want the water in the fountain behind your model to be completely frozen by a shutter speed of 1/5000 of a second, you might decide to apply some neutral density filters, and to save you the trouble of remembering your shutter speed, I’ve also added a To ND Calc button at the top of the screen, above your calculated shutter speed, which, as you might imagine, will send your new shutter speed directly to the ND calculator and open it for you. This is also useful if you have calculated a shutter speed of five seconds or more and need a timer. Just jump over to the ND Calculator and hit the timer button.
Likewise, the To DoF Calc button will send your aperture to the Depth of Field calculator so that you can see how much depth of field you have at the currently selected or calculated aperture.
So, I hope this has helped a little if the concept of Exposure Values wasn’t something that you are familiar with. As with the other two calculators, as well as actually helping you to work in the field, they are great for learning the theory behind exposure and depth of field, as well as teaching it. Even if you have all this down, there’s nothing like being able to turn dials and show the effects of your changes to help people understand this stuff. Then hopefully when you are advised to increase your exposure by one or two stops, you’ll be better equipped to calculate the difference in your head, or reach for your iPhone and open the Photographer’s Friend.
Photographer’s Friend 3 Coming Soon!
As I said, my current plan is to make this a paid upgrade, so if you like what you see, but don’t already own version two, then please wait for a few days until I release version three. If you are reading or listening after more than a few days into September 2018 though, version three should already be available. And for those of you that have version two, I will try to provide a reasonable upgrade path, details of which will be provided in an update to version two of the app. If you don’t need the Exposure Shift calculator, you are more than welcome to continue to use version two, and I have a few improvements for version two that will be released very soon as well, so you won’t be left out to dry.
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Today I explain the effect that changing your subject distance and focal length has on the perspective of the visual elements in your photographs. This is often confused with a change in perspective due to your lenses focal length alone, but that really isn’t the case. Let me explain why.
I’m actually writing this post on request from my friends over at Craft & Vision. They asked me to do this last year, and I’m just getting to it now that the dust is settling after my winter tour season. I also shot the example photos that we’ll reference on the park near my brother’s house in the UK on Christmas Eve 2016. They aren’t great photos, but I wanted a scene with two distinct elements in it, one close by and one far away, so that we could see the effect I’m going to explain.
Focal Length Alone Does Not Change Perspective
People sometimes get confused when talking about this subject, and end up talking about how changing the focal length changes the perspective, and it actually does not. The only time the perspective changes is if you change the distance from your camera to the subject.
If you also change your focal length to maintain the same subject size, you will see a dramatic change in the relationship between the foreground subjects and the elements in the background. If you simply put a camera on a tripod, and without changing the distance to your subject, then shoot a series of images as you zoom in or out, you can crop away the excess image that is captured in the images at wider focal lengths, and you’ll see that the relationship between the main subject and the background will be exactly the same. The perspective itself does not change by changing the focal length alone.
The reason the perspective will change in my example photos, is because I moved closer to my main subject and zoomed out, changing my focal length, to make the the main subject appear the same size in each photograph. When you do this, the relationship between the subject and the background elements changes dramatically, as we’ll see.
The Effect of Subject Distance on Perspective
Let’s take a look at my example shots to explain. For these examples, I needed a nearby and a distant subject, so that I could easily explain this theory. I grew up playing in this park on holidays and weekends, and knew that I’d be able to find a tree to place in front of the power station in the distance, so let’s work with this.
My first image was shot at 105mm, from a distance of approximately 100 meters (330 ft). After making this first exposure, I made a mental note of where the tree was in the frame, so that I can recreate that as I moved closer.
I changed my 24-105mm lens from 105mm to 70mm, looking at the focal length markings on the barrel of the lens. Then I walked closer to the tree, checking the size of the tree in the frame, until I got it approximately the same size as in my first photograph. This second image was shot at 70mm from a distance of approximately 70 meters (230 ft). Notice how the tree is the same size, but the power station behind it has shrunk a little.
I repeated the process, changing the focal length of my lens from 70mm to 50mm, and moved closer still to the tree, until it was the same size in the frame again and shot my third image approximately 55 meters (180 ft). Once again, see how much smaller the power station has become.
For my final image I zoomed all the way out to 24mm and moved close enough for the tree to look the same size in the frame, and shot this from approximately 25 meters (82 ft).
To compare these four images, you can click on them to open the images in a viewer, and then click the right or left side of the images to move back and forth.
When you compare all four of these images, you’ll see that the tree is pretty much the same size in each, but if you look at the apparent size of the power station in the background, you’ll see that it changes dramatically as we get closer to the tree and zoom out to maintain the size of the tree. Let move on to explain why this happens.
Field of View
As we change the focal length of our lenses, we change their field of view. This is how much of the world we are able to capture in our image, and it’s directly linked to the focal length. On a full frame or 35mm sensor camera, at 105mm we can photograph horizontally 20° of the world around us. At 70mm we get 30°, at 50mm we get 40° and at 24mm, 75° of the scene before us enters our lens.
You can usually find the field of view for your lenses on the manufacturer’s web site, but I checked the field of view for each of my example photographs with a program called Raw Digger, that allows me to dig into my EXIF data. Canon actually write the field of view for the focal length used in the EXIF data of each image, and that’s really handy.
I also went into Canon’s Map Utility that comes with my GP-E2 device that I use to geotag my images, and using the scale on the map and a rule against my computer display, I calculated the shooting distances that I mentioned earlier. With these two pieces of information, we can easily chart out the relationship between the four example images, including our shooting distance and the angle of view, as you can see in this diagram (below).
After you click to view it larger, to stop the image from automatically advancing, just place your mouse cursor over the image.
Calculate Subject Size Based on Distance and Degree
To really explain this we’re going to have to get a bit geeky. Believe me, I’m no mathematician. It was my worst subject at school and I hate numbers, except when it comes to something that I’m interested in, like business, computers and photography, then I do like to dig down a little. First of all, for my own sake, I want to make sure that I’m doing this right, and to do that, I first figured out how to calculate the size of the tree in the photograph.
We know that Π (pi) = 3.14159, so if we divide 180 degrees, the widest field of view we’re ever likely to be using in photography, by 3.14159, we get 57. That means we can calculate the size of an object by multiplying the distance by the field of view in degrees and dividing that by 57.
Armed with this formula, we can calculate that at 105mm, when I first photographed the tree from a distance of approximately 100m, the field of view captured in the photograph was about 35 meters at the distance of the tree.
100 × 20 ÷ 57 = 35 meters
In Adobe Illustrator I resized the example images to 1,000 pixels wide, and used the measure tool to find that tree was 440 pixels wide, so it’s taking up 44% of the field of view. So we can multiply 35 by 0.44 to learn that the tree is approximately 15.4 meters across at its widest point. That sounds about right!
Width of Subject = Subject Distance × Field of View ÷ 57 × Subject Width (i.e. 44% = 0.44)
If we take the widest focal length of 24mm and do the calculation, we get roughly the same answer. At 24mm the field of view is 75° and I photographed the tree from 25 meters. So, 25 x 75 / 57 x 0.44 equals 14.4 meters. There’s a small variance, but I’m getting my actual shooting distance from my GPS information, and measuring it with a very small rule on a computer screen. There may also be something going on as we focus the lens, so I’m not too concerned about this variance. It’s close enough to prove to me at least, that my math isn’t too cranky.
Near and Far Objects
We can also mathematically understand why the power station gets smaller in relation to the tree, starting by doing the same calculations. Measuring out the distance from where I was when I took these photos, we are about 3,500 meters from the power station and it takes up approximately 37% of the field of view in the 105mm focal length photograph, so, 3500 x 20 / 57 = 1228 x 0.37, the power station is about 454 meters wide from this angle.
In the 24mm photograph, the power station takes up about 10% of the field of view, and we’ve moved 75m closer to the subject so 3425 x 75 / 57 x 0.1, which comes to 450 meters. Again, there is a very slight variance, but based on this we can see that we are able to approximately calculate the size of the objects in the frame based on the distance to the objects and the field of view of our lens at any given focal length.
Field of View in the Distance
To understand why distant objects are smaller in wider focal length images, let’s do one last pair of calculations, and find the width of our slice of world captured at the distance of the power station, kind of as a checksum. We actually got these numbers as part of our previous calculation, but to recap, we know that the power station is approximately 3500 meters away in our 105mm photo which has a field of view of 20°. At 100 meters, where the tree is, this captures 35 meter of the scene, but if we extend this out to where the power station is, we are capturing 1,228 meters of the world.
At 25 meters with a focal length of 24mm we are capturing 33 meters of the world, but at 3,425 meters, where the power station is, that captures a 4,500 meter wide scene. So an object which is approximately 450mm wide is going to take up 10% of a 24mm image, as opposed to 37% of a 105mm photograph. We know that we maintained the tree size at 44%, so this is our proof for why things get smaller as they get further away.
Not being very good at maths, after spending most of the day working on these formula, you can probably imagine how happy I was when I entered my calculations into an Excel spreadsheet, and calculated the size of the tree and power station based on field of view and distance alone, and then calculated that the percentage of the width that the power station would take in my images, was exactly the same as that which I’d calculated by measuring the pixels in Adobe Illustrator.
One Sentence Take-Away
In practical use, we simply need to remember the following sentence.
As we widen our focal length and move closer to our main subject the background elements in our scene will appear smaller.
That’s it! I know that this is somewhat obvious, and many of you will look at this alone, and think, I knew that! And that’s great, but I hope now that you’ll have a better understanding of why this happens. I know I understand it better than I did this morning, when I sat down to think about the math.
A Practical Examples
Let’s look at a few more photos from the field, not shot to illustrate this point per se, but they will help to get a better understanding of how different our images can be just by thinking about the distance to subject and focal length.
Here is a photo of a tree in front of a sand dune in Namibia (below), which I shot from 85 meters (280 ft) from the tree. Again, I know this because I geotag my images and checked on Google maps. My focal length for this was 80mm, but I cropped in a little along the top, so it’s probably the equivalent of 90mm.
The next image (right) was part of a series of images that I shot vertically to stitch together as a panorama, but it didn’t work, because the dune looked tiny in relation to the tree. In all honesty I don’t really know why I proceed to shoot the series, but it helps to illustrate this point, so all is good.
I actually shot this from around 30 meters (100 ft) away from the tree. Because I’ve gone to portrait/vertical orientation with the camera for this photo, we automatically get more foreground and sky, so it’s not a straight comparison, but you will surely be able to appreciate how going a little bit wider and moving closer to the subject has shrunk the apparent size of the background.
Knowing that the final image is what I wanted, I actually exposed the next photograph (below) before the others, from around 75 meters (250 ft) away from the tree, with a focal length of 165mm.
I think you’ll appreciate that the background looks very different in the long focal length shot, from a distance, compared to the shorter focal length shot closer to the tree, even though the dune starts pretty close behind the tree. But, because the sand dune is so large, it quickly recedes into the distance, and so starts to shrink in relationship with this tree very quickly.
Finally, here’s one last image (right) that I made as we walked away from this sand dune. I shot this at a distance of 1.3km (4,400 ft) with a focal length of 200mm.
Obviously now the tree is much smaller in the frame from this distance, but I want you to think about the difference between how the tree looks in this shot compared to the first two photographs of this tree and dune above. In all three images we can see the tree with the sand dune from top to bottom.
The apparent size of the tree compared to the sand dune is portrayed totally differently simply by changing my focal length and distance to the tree from the camera.
Don’t Zoom With Your Feet Just Because
One other thing that I’d like to mention, is that you’ll often hear people talking about zooming with your feet. Just as I did to get closer to this sand dune. Zoom with your feet is one of those mantras that people latch on to and use for a number of reasons.
I’m not going to go into details on my theories here, but I imagine that part of the reason for the popularity of this phrase is because people need to protect their egos, by backing up a decision to buy, or sometimes to not buy, a certain piece of gear. Worse still, sometimes people are just regurgitating a phrase that someone who should know better said in a confident tone.
Personally, when I’m photographing wild animals or photographing a valley from a cliff edge, I prefer not to walk forwards. In a situation when you can move forwards, you need to be making your decision to do so based on how the focal length, or more specifically the field of view, and the distance to your subject and scene will effect the look of your photograph. You definitely don’t want to be zooming with your feet just because someone etched the phrase zoom with your feet into your brain.
I hope that what we’ve covered today will help you to make an educated decision for yourself, as to whether it’s better to move closer to your subject, or shoot it from further away, while zooming with your lens, not your feet.