For chapter one in my book Stunning Digital Photography, I want to go over some quick tips that can really quickly improve your
photography. I'm going to use my favorite model here, Cowboy. The first tip that I have is that I
don't carry a camera bag around nor do I use a lens cap. You see all I have is a camera strap When you carry all that extra gear it
just slows you down.
Every time you go to take a picture you have to spend a few seconds taking your camera
out, maybe digging through all those different lenses. So here's tip number two, and it's to
eliminate distractions so this is how most people would take a
picture. They would just stand at eye level and take a nice wide angle shot. Nice smile, Cowboy.
And what happens there is, you don't really know what
the subject to the picture is, it looks fine when you're seeing it with your eye. But when you look at the actual photo, you
see a lot of things in the picture besides the
subject. To eliminate distractions, the easiest thing to do is to get closer and to zoom
in. So I'll do that now.
Cowboy, look up here. Good boy! Getting closer also reduces the depth of field, it blurs the
background a little bit which I cover in depth in Chapter four. The next thing to do, tip
number three is to try different viewpoints. So, I just shot Cowboy from eye level and it's not that flattering.
For smaller
subjects like dogs, you really wanna crouch down and get to the eye level same thing applies for kids. Good boy,
Cowboy. If you're taking pictures of something like
the Eiffel Tower, you can move to many different sides of it get high and get low, get close, zoom in
zoom out that leads me to tip number four which
is take lots og pictures but delete most at them. You can't take too
many pictures with digital, it doesn't cost you a thing but please don't put 150 pictures of the
same thing on Facebook.
Just pick one. For tip number 5 I would
like to talk about flash. Now by default your camera just points the
flash directly at your subject which provides a very flat lighting I'll take a sample shot now. A better way to
do it is to use bounce flash.
Many cameras allow you to attach an
external flash to the hot shoe With the bounce flash you can angle the
flash up. Many bounce flashes even have a diffuser built in that will spread the
light a little bit more evenly. Now as I take a second picture of Cowboy you'll notice that the lighting is very different the background has more even shadows, the lighting overall looks more natural And if he had red eye in the first
picture, he wouldn't have red eye in this picture For my last tip, I want to suggest that you edit your photos. All you need to do is
to download a free application like Picasa and just give it a little crop, maybe adjust
the colors and the white balance until looks good Often the application can edit the
settings automatically This was for chapter one in my book
stunning digital photography this was the most basic video and
chapter in the series after this it gets much more complex I can take you from beginner to
very advanced amateur or even professional if you're willing to put the
time into it.
The print book is about twenty dollars. If you get the ebook which is just a few dollars, you should be able to watch videos like this embedded right in it, many videos
which you can't find on YouTube or other sources. If you like this video
click subscribe above to see other videos like it and click like down below. If you have any questions
for me add them to the comments below I'll get
right back to you.
Thanks. High five Cowboy! Alright! [Background laughter].
Wednesday, October 24, 2018
Tuesday, October 16, 2018
Raw vs JPEG Real-world photography examples, advantages and disadvantages
Hi, I'm Tony Northrup, and for the book Stunning Digital Photography I'd like to talk about raw files. Raw
files take all the data captured by your camera sensor
and put it into a really big file that you can process later.
Now that's distinct from a jpeg file. If you use jpeg files,
your camera takes all that raw data and processes
it in camera and then you get to work with that
processed file. Now you might notice that a jpeg file tends to be about three
megabytes, whereas a raw file might be 25 megabytes.
The difference is important.
The raw file's giving you way way way more data. In fact,
it's giving every bit of data that the sensor captures. The jpeg file drops an awful lot of that data. Your jpeg pictures might still look good,
but they don't have all the data in them.
For example a raw file will capture, let's say, 10,000 different bits, different gradients, from black to white and it will store them all. When you
save it as a jpeg file, it has to clip the top and bottom part of that. It clips some the shadows and some of the
highlights and that means you're losing detail. To demonstrate that, let's look at
some jpeg files and raw files in my photo editing app, Lightroom.
Here I have a picture of a train shot in both raw and jpeg. And you can see that this is a pretty
challenging scenario, I'm shooting directly into the sun here. I'll switch over to the develop module and
try to recover some of the highlights. You can see I am able to retrieve some of the information.
Now let's look at the RAW file instead. Now, you can see how much more information I
was able to recover there. I was able to see quite a bit more of the
train in that one than in here. You can see
how much more that sunburst covers up.
Now I'll switch over to the raw file one more
time and bring up the shadows a little bit. And
you can see that I'm able to get a much clearer picture from the raw file than I could from the
jpeg file. Another good use for raw files is white
balance. In this night shot of the Brooklyn bridge you can see the white balance is
terrible.
With a jpeg file you can adjust the white
balance, but it's not quite as perfect because your camera has already decided
upon the white balance in camera and set that permanently for
you. With a raw file, you have quite a bit
more flexibility and you don't have to worry about any data loss, so you can fix the white balance and you will still retain perfect detail
as if you had set the white balance correctly in the first place. Of course it's always ideal, but you don't have to make those decisions at the time you're shooting with a raw file. You get to make those decisions later.
Which means, if you happent to make a mistake or if the lighting situation is such that it
would be impossible to pick one right answer, you can fix it in post as long as you
shoot RAW. This gives you more power later on. Let's look at a couple more examples. This is Shibuyo station in Tokyo, Japan and it's the busiest intersection in the world.
Which means I
couldn't necessarily bracket shots, because you can see just how much
movement there is here. So HDR wouldn't work to capture this
huge dynamic range between the darks and the blown-out highlights here. You know, look at the sign up here and you can see you can't read those words at all, this is completely white. With raw, I
can drag these highlights down and suddenly the sign is completely
readable.
Take a look at this area of the sign over here and how much is lost versus how much can be recovered. Now I'll switch over to the jpeg file and we'll
look at the same blue sign up here. I'll try to recover the highlights and you'll
see it's just not as good. Do a before and after with the raw file.
That's the raw file, and that's the jpeg file.
Once again the
raw file shows far more detail and the jpeg just has
more and more blown out. Here is another example, this is a sunset shot of the Boston skyline, and you can see it's at dusk but the sky is completely blown out. This is actually a great exposure for a night shot because I'm capturing all the detail in the shadows
here and if it were a jpeg the shot would just be a loss. But with a raw file I can drag those
highlights down and you can just see a ton of detail
in the sky.
You can see even though the sky looked over-exposed
initially there's absolutely no detail lost. Lot's of dust here, but you can see these
wispy clouds. Now let me switch over to the jpeg file
and I'll drop the exposure down to recover the highlights, and you can see
what happens. There's a little bit of detail that can be
recovered but you see these terrible lines up here.
Switching back to the raw file just
looks so much better. Here's another high dynamic range situation, this one in the day. You can see this ruin in Ireland is completely in shadow
because you have these overcast skies here. But there's a great
deal of detail in both the shadows and the highlights here.
So, with the raw file I can drag up these shadows and drag down these highlights and just overall reduce the contrast of it. Now, let me pull the blues down a little bit to show some more detail in the sky. And, wow, that's just a lot of detail that
was recovered in that picture. Now let's take a look at the jpeg file.
That's the jpeg file... And this is the
raw file edited. Now I can try to do that same
editing here in the jpeg file. And you can see I'm able
to recover some of it drag the blues down.
You can see after processing the
raw file just looks much much better. Because you have all that extra
information. When you choose jpeg files, your camera
processes that in the camera and just throws away that information forever. When you pick raw, you can always go back and save it and you have all the detail that your camera sensor
was able to capture.
Wildlife shots can be really challenging because you don't necessarily get to make adjustments and shoot later. Here I saw this ibis flying and I had to
captured it with whatever settings I had, I didn't get to take a picture and then look at my
settings and think about it. And I did a pretty good job but you can see it's a little bit
underexposed. That the detail that we wanna see are these gorgeous colors in the bird's wings and in a jpeg file, that
would be lost.
But, look here in the raw file and you'll see that we can recover a great deal of detail in this picture.
I'll drag the exposure up and pull these shadows up and you'll see what happens. Now that's just amazing, you can see all this
metallic color in this ibis, just really beautiful. And with a jpeg
file all that would be lost. Here is a little more extreme example, this osprey had caught a fish but because the sky was overcast it's
completely blown out and he's completely in shadow.
Now, here's an answer- wait around for
better lighting, right? But you don't always necissarily wanna waste
a whole day of shooting because I had bad weather that day. But with raw, this
file can be recovered. So the first thing I'll do is pull the
highlights down to recover some blue in the sky and then I'll just drag
the shadows up some. Pull the exposure up a little until the
bird is well exposed.
Some more shadows and then drop the blacks down And you can see I ended up with a pretty
good picture Another wildlife picture. I shot this flycatcher at sunset and it was just beautiful. And the lighting is
beautiful, you can see, because the reeds are backlit, that they're kind of glowing.
With wildlife usually want the subject to be front-lit, but I wouldn't have had the
beautiful lighting on the reeds if I did that. With raw, however, I can expose it properly
for the reeds and then recover so much of the shadow detail that you'll be able
to see the bird nicely.
So I'll pull up the shadows here bump the exposure up just a little bit and you can see it ended up being just really nice picture. So I hope
you'll check your camera's manual and learn how to turn on raw files for it. There are a few disadvantages that you
should know about. Raw files are way bigger and that's where the
disadvantages come from.
You can fit fewer pictures on a single memory
card, so you are going to need bigger memory cards or more of them. You fun out of buffer faster, so if you're, say,
shooting wildlife or sports and you're holding down that shutter on continuous you might find that you run out of buffer
in six or seven pictures. It depends on the camera, but after you run out of buffer the number of pictures you can take is gonna slow down a lot. Like it's gonna go from being 4 or 5 pictures a second to one picture a
second.
So if you find that you're running out of buffer all the time, it might be better to switch back to jpeg. It also takes up a lot more disk space. If you take thousands of pictures a week
you could find yourself buying a new hard drive pretty soon, but nowadays hard
drives are so cheap I say go for raw, delete the pictures you
don't need and you probably won't have any problem with that at all. If you liked this video, please click
subscribe up above and like down below.
And I hope that you'll check out my
book, Stunning Digital Photography, which has more than two hours of
instructional video. It focuses on photographic technique, so you'll learn
how to get the picture right in camera but I also show you all the advantages
of using raw in different scenarios including for night photography and HDR. Thanks..
files take all the data captured by your camera sensor
and put it into a really big file that you can process later.
Now that's distinct from a jpeg file. If you use jpeg files,
your camera takes all that raw data and processes
it in camera and then you get to work with that
processed file. Now you might notice that a jpeg file tends to be about three
megabytes, whereas a raw file might be 25 megabytes.
The difference is important.
The raw file's giving you way way way more data. In fact,
it's giving every bit of data that the sensor captures. The jpeg file drops an awful lot of that data. Your jpeg pictures might still look good,
but they don't have all the data in them.
For example a raw file will capture, let's say, 10,000 different bits, different gradients, from black to white and it will store them all. When you
save it as a jpeg file, it has to clip the top and bottom part of that. It clips some the shadows and some of the
highlights and that means you're losing detail. To demonstrate that, let's look at
some jpeg files and raw files in my photo editing app, Lightroom.
Here I have a picture of a train shot in both raw and jpeg. And you can see that this is a pretty
challenging scenario, I'm shooting directly into the sun here. I'll switch over to the develop module and
try to recover some of the highlights. You can see I am able to retrieve some of the information.
Now let's look at the RAW file instead. Now, you can see how much more information I
was able to recover there. I was able to see quite a bit more of the
train in that one than in here. You can see
how much more that sunburst covers up.
Now I'll switch over to the raw file one more
time and bring up the shadows a little bit. And
you can see that I'm able to get a much clearer picture from the raw file than I could from the
jpeg file. Another good use for raw files is white
balance. In this night shot of the Brooklyn bridge you can see the white balance is
terrible.
With a jpeg file you can adjust the white
balance, but it's not quite as perfect because your camera has already decided
upon the white balance in camera and set that permanently for
you. With a raw file, you have quite a bit
more flexibility and you don't have to worry about any data loss, so you can fix the white balance and you will still retain perfect detail
as if you had set the white balance correctly in the first place. Of course it's always ideal, but you don't have to make those decisions at the time you're shooting with a raw file. You get to make those decisions later.
Which means, if you happent to make a mistake or if the lighting situation is such that it
would be impossible to pick one right answer, you can fix it in post as long as you
shoot RAW. This gives you more power later on. Let's look at a couple more examples. This is Shibuyo station in Tokyo, Japan and it's the busiest intersection in the world.
Which means I
couldn't necessarily bracket shots, because you can see just how much
movement there is here. So HDR wouldn't work to capture this
huge dynamic range between the darks and the blown-out highlights here. You know, look at the sign up here and you can see you can't read those words at all, this is completely white. With raw, I
can drag these highlights down and suddenly the sign is completely
readable.
Take a look at this area of the sign over here and how much is lost versus how much can be recovered. Now I'll switch over to the jpeg file and we'll
look at the same blue sign up here. I'll try to recover the highlights and you'll
see it's just not as good. Do a before and after with the raw file.
That's the raw file, and that's the jpeg file.
Once again the
raw file shows far more detail and the jpeg just has
more and more blown out. Here is another example, this is a sunset shot of the Boston skyline, and you can see it's at dusk but the sky is completely blown out. This is actually a great exposure for a night shot because I'm capturing all the detail in the shadows
here and if it were a jpeg the shot would just be a loss. But with a raw file I can drag those
highlights down and you can just see a ton of detail
in the sky.
You can see even though the sky looked over-exposed
initially there's absolutely no detail lost. Lot's of dust here, but you can see these
wispy clouds. Now let me switch over to the jpeg file
and I'll drop the exposure down to recover the highlights, and you can see
what happens. There's a little bit of detail that can be
recovered but you see these terrible lines up here.
Switching back to the raw file just
looks so much better. Here's another high dynamic range situation, this one in the day. You can see this ruin in Ireland is completely in shadow
because you have these overcast skies here. But there's a great
deal of detail in both the shadows and the highlights here.
So, with the raw file I can drag up these shadows and drag down these highlights and just overall reduce the contrast of it. Now, let me pull the blues down a little bit to show some more detail in the sky. And, wow, that's just a lot of detail that
was recovered in that picture. Now let's take a look at the jpeg file.
That's the jpeg file... And this is the
raw file edited. Now I can try to do that same
editing here in the jpeg file. And you can see I'm able
to recover some of it drag the blues down.
You can see after processing the
raw file just looks much much better. Because you have all that extra
information. When you choose jpeg files, your camera
processes that in the camera and just throws away that information forever. When you pick raw, you can always go back and save it and you have all the detail that your camera sensor
was able to capture.
Wildlife shots can be really challenging because you don't necessarily get to make adjustments and shoot later. Here I saw this ibis flying and I had to
captured it with whatever settings I had, I didn't get to take a picture and then look at my
settings and think about it. And I did a pretty good job but you can see it's a little bit
underexposed. That the detail that we wanna see are these gorgeous colors in the bird's wings and in a jpeg file, that
would be lost.
But, look here in the raw file and you'll see that we can recover a great deal of detail in this picture.
I'll drag the exposure up and pull these shadows up and you'll see what happens. Now that's just amazing, you can see all this
metallic color in this ibis, just really beautiful. And with a jpeg
file all that would be lost. Here is a little more extreme example, this osprey had caught a fish but because the sky was overcast it's
completely blown out and he's completely in shadow.
Now, here's an answer- wait around for
better lighting, right? But you don't always necissarily wanna waste
a whole day of shooting because I had bad weather that day. But with raw, this
file can be recovered. So the first thing I'll do is pull the
highlights down to recover some blue in the sky and then I'll just drag
the shadows up some. Pull the exposure up a little until the
bird is well exposed.
Some more shadows and then drop the blacks down And you can see I ended up with a pretty
good picture Another wildlife picture. I shot this flycatcher at sunset and it was just beautiful. And the lighting is
beautiful, you can see, because the reeds are backlit, that they're kind of glowing.
With wildlife usually want the subject to be front-lit, but I wouldn't have had the
beautiful lighting on the reeds if I did that. With raw, however, I can expose it properly
for the reeds and then recover so much of the shadow detail that you'll be able
to see the bird nicely.
So I'll pull up the shadows here bump the exposure up just a little bit and you can see it ended up being just really nice picture. So I hope
you'll check your camera's manual and learn how to turn on raw files for it. There are a few disadvantages that you
should know about. Raw files are way bigger and that's where the
disadvantages come from.
You can fit fewer pictures on a single memory
card, so you are going to need bigger memory cards or more of them. You fun out of buffer faster, so if you're, say,
shooting wildlife or sports and you're holding down that shutter on continuous you might find that you run out of buffer
in six or seven pictures. It depends on the camera, but after you run out of buffer the number of pictures you can take is gonna slow down a lot. Like it's gonna go from being 4 or 5 pictures a second to one picture a
second.
So if you find that you're running out of buffer all the time, it might be better to switch back to jpeg. It also takes up a lot more disk space. If you take thousands of pictures a week
you could find yourself buying a new hard drive pretty soon, but nowadays hard
drives are so cheap I say go for raw, delete the pictures you
don't need and you probably won't have any problem with that at all. If you liked this video, please click
subscribe up above and like down below.
And I hope that you'll check out my
book, Stunning Digital Photography, which has more than two hours of
instructional video. It focuses on photographic technique, so you'll learn
how to get the picture right in camera but I also show you all the advantages
of using raw in different scenarios including for night photography and HDR. Thanks..
Monday, October 8, 2018
Physics 109, Lab 12 Digital Photography
In this lab we will investigate a typical
modern point and shoot digital camera to see how it works.
The camera you will be using is Canon G7, a point and shoot camera which can be controlled
from the computer. In particular you will learn about focus,
exposure time, aperture and ISO. In automatic mode a digital camera will choose
these settings for you, but if you want to take creative photographs, you have to know
how to choose them yourself In digital cameras , the image sensor is a
charge-coupled device, or "CCD" . When the sensor is exposed to light, the charge
distribution changes.
This new charge distribution is then read
off and processed into an image. Whereas in film camera, the image is formed
on a film which is a length of plastic that has been coated with certain chemicals. When
a picture is taken, the film is exposed to light in a controlled manner, using lenses,
an aperture and shutter. To begin the lab
Switch on the camera and connect to the computer.
Then open up the zoombrowser ex software that
you will use to control the camera. Click on acquire and camera settings and then connect
to camera. Then select the remote shooting tab and click start remote shooting.
Select the folder where to save the images. The camera is now connected and you can set
the camera settings.
Set the ISO to 400 AE. Mode to manual, exposure time which is referred
to as Tv in zoombrowser to 1/50 and aperture that is Av to 4.5. Then press release to grab
a picture. You can then zoom into the picture to see the pixels
us the slider on the upper left of the window to zoom in and out.
Zoom in until you can see the pixels, and out again until you cant see the pixels
any more You can also check the image size by checking
the properties panel.
When you change the focus on the camera, you
are changing the "image distance"- the distance from the lens to the image sensor-- while
leaving the focal length the same. This is done by moving the lens relative to the sensor.
If the image distance is changed, but the focal length is not, this has the same effect
as changing the object distance . You can see this in the lens equation. If f is constant
then the left hand side of equation should remain the same that means if either i or
o is varied the other one has to change to get a proper image in focus.
Increasing the distance between the lens and
the real image actually increases the total size of the real image.
The same basic thing happens in a camera. As the distance between the lens and the real
image increases, the light beams spread out more, forming a larger real image. Here you can see the camera changing the image
distance by moving the lens away from the sensor. In this section you will test the exposure
time, using the light-emitting diode(LED), and an audio generator.
Begin by setting the
frequency of the audio generator to 10HZ. Set the exposure time to 1/10 of a second
and ISO to 100. Take pictures of the diode, with different values of exposure time and
by changing the frequency of flashes accordingly. The number of bright dots varies with different
settings of frequency and different values of exposure time.
In these photographs, the
exposure time set to 1/10 of a second, the red led is on frequency 10hz, green one on
20Hz and yellow on 30 hz, that is why only one red dot is visible whereas there are two
and three green dots. The aperture of a camera is the hole through
which light has to pass in order for a picture to be made. The bigger the aperture, the more
light gets in, and the brighter is the image captured.
Here, you can observe the changing aperture by looking at the center of the lens. Next we come to ISO.
ISO controls the sensitivity
of the image sensor to light. The higher the ISO number, the more sensitive the camera
is. In this photo the graininess is caused due to a high iso number. Whereas this is
a photo of the same object with lower iso number.
Next we study the relation between aperture
and depth of field. First place a notebook 20 cm in front of the camera and lock the
auto focus, then set the aperture to 8 and exposure to 1/10 of a second. Then change
the aperture to 2.8 And exposure to 1/80 and take another photograph. You will observe
that the photograph with small has a larger depth of field as compared to the one with
bigger aperture..
modern point and shoot digital camera to see how it works.
The camera you will be using is Canon G7, a point and shoot camera which can be controlled
from the computer. In particular you will learn about focus,
exposure time, aperture and ISO. In automatic mode a digital camera will choose
these settings for you, but if you want to take creative photographs, you have to know
how to choose them yourself In digital cameras , the image sensor is a
charge-coupled device, or "CCD" . When the sensor is exposed to light, the charge
distribution changes.
This new charge distribution is then read
off and processed into an image. Whereas in film camera, the image is formed
on a film which is a length of plastic that has been coated with certain chemicals. When
a picture is taken, the film is exposed to light in a controlled manner, using lenses,
an aperture and shutter. To begin the lab
Switch on the camera and connect to the computer.
Then open up the zoombrowser ex software that
you will use to control the camera. Click on acquire and camera settings and then connect
to camera. Then select the remote shooting tab and click start remote shooting.
Select the folder where to save the images. The camera is now connected and you can set
the camera settings.
Set the ISO to 400 AE. Mode to manual, exposure time which is referred
to as Tv in zoombrowser to 1/50 and aperture that is Av to 4.5. Then press release to grab
a picture. You can then zoom into the picture to see the pixels
us the slider on the upper left of the window to zoom in and out.
Zoom in until you can see the pixels, and out again until you cant see the pixels
any more You can also check the image size by checking
the properties panel.
When you change the focus on the camera, you
are changing the "image distance"- the distance from the lens to the image sensor-- while
leaving the focal length the same. This is done by moving the lens relative to the sensor.
If the image distance is changed, but the focal length is not, this has the same effect
as changing the object distance . You can see this in the lens equation. If f is constant
then the left hand side of equation should remain the same that means if either i or
o is varied the other one has to change to get a proper image in focus.
Increasing the distance between the lens and
the real image actually increases the total size of the real image.
The same basic thing happens in a camera. As the distance between the lens and the real
image increases, the light beams spread out more, forming a larger real image. Here you can see the camera changing the image
distance by moving the lens away from the sensor. In this section you will test the exposure
time, using the light-emitting diode(LED), and an audio generator.
Begin by setting the
frequency of the audio generator to 10HZ. Set the exposure time to 1/10 of a second
and ISO to 100. Take pictures of the diode, with different values of exposure time and
by changing the frequency of flashes accordingly. The number of bright dots varies with different
settings of frequency and different values of exposure time.
In these photographs, the
exposure time set to 1/10 of a second, the red led is on frequency 10hz, green one on
20Hz and yellow on 30 hz, that is why only one red dot is visible whereas there are two
and three green dots. The aperture of a camera is the hole through
which light has to pass in order for a picture to be made. The bigger the aperture, the more
light gets in, and the brighter is the image captured.
Here, you can observe the changing aperture by looking at the center of the lens. Next we come to ISO.
ISO controls the sensitivity
of the image sensor to light. The higher the ISO number, the more sensitive the camera
is. In this photo the graininess is caused due to a high iso number. Whereas this is
a photo of the same object with lower iso number.
Next we study the relation between aperture
and depth of field. First place a notebook 20 cm in front of the camera and lock the
auto focus, then set the aperture to 8 and exposure to 1/10 of a second. Then change
the aperture to 2.8 And exposure to 1/80 and take another photograph. You will observe
that the photograph with small has a larger depth of field as compared to the one with
bigger aperture..
Subscribe to:
Posts (Atom)