Go to full frame is a responsible matter. First of all, of course, because of the high cost of such cameras. Therefore, photographers often have a question: buy a new lens or save up for a full frame? People also ask: Should I take a full frame right away or get by with a crop when buying the first camera? In this article, I will answer these and other questions in as much detail as possible.

About marketing

The efforts of marketers today are aimed at making people strive to buy the coolest camera and the most expensive lens. And it works. If it weren't for the prices, everyone would go with full frame cameras and L lenses. It just doesn't make sense, really.

Why?

Good photo, according to my estimates, consists of:

  • 10% coolness of your camera
  • 30% of the quality of your optics
  • 30% straightness of your hands when shooting
  • 30% post-processing literacy

Marketers of photographic equipment manufacturing companies play along with the aspirations of many, convincing them that they need to buy a cooler camera. The more megapixels, the more working ISOs, than faster speed autofocus, etc., the supposedly better photos will be.

The specific ratios of these factors depend on the genre of photography. For example, for I would estimate the ratio somewhere like this:

  • 5% camera and lens
  • 45% ability to expose light
  • 50% post-processing care

New lens or camera?

When choosing between upgrading a lens or a camera, it is also better to buy first. Moreover, you can afford an order of magnitude more variety on crop. A relatively inexpensive set that I would recommend for complete photographic happiness to start with:

  • any modern Canon crop camera
  • Canon EF-S 10-18mm f4.5-5.6 IS STM
  • Canon EF-S 24mm f2.8 STM
  • Canon EF-S 18-135mm f3.5-5.6 IS STM

All this together costs about the same as one full-frame camera without a lens. But you get the widest range of focal lengths with very compact, inexpensive and high-quality optics. A similar range on a full frame will cost 3 times more.

I wrote in detail about crop lenses in .

Let's get down to specifics.

What are the advantages of full frame over crop?

1) Wider dynamic range
2) Higher working ISO values
3) Better sharpness throughout the frame
4) Higher resolution
5) Convenience of focal lengths
6) More comfortable body

And now about each point in more detail.

1) dynamic range.

What it is? This is the width of the light spectrum that is captured in the photograph, the number of shades between completely light and completely dark color. It has always been believed that digital cameras are inferior to film cameras in this parameter. But full-frame digital DSLRs can argue with this statement. Crop cameras, on the other hand, are much more likely to produce white spots in the bright areas of photos and dark dips in the shadows.

Why is this needed? Here is the most main question. It all depends on the type of shoot. In particular, a wide dynamic range has almost no effect on shooting in a studio with pulsed light. This is important when shooting outdoors, and for landscapes.

Here comes another question, How many people even notice it? In my experience - No. It’s especially funny when people shoot with expensive high-aperture optics at full frame, and then apply effects a la instagram to the photo, completely killing them there paid for with hard earned money dynamic range.

2) High ISO

Due to the larger size of the sensor and the increase in the physical size of the pixel, full-frame cameras capture more light. As a result, you can shoot at higher ISOs without noise. It's really very convenient. But it should also be borne in mind that modern crop cameras already have very good parameters. For example, the old full-frame Canon 5D at ISO 400 already produced tolerable but noticeable noise. New crops shoot tolerably at ISO 1600.

3) sharpness

Total.

A camera with a full frame is, by the way, also a reason for subsequent spending on expensive optics. My opinion is that such an acquisition makes sense for experienced photographers who know why and for what they need it. Do I need to switch from crop to full frame? Decide for everyone personally. The main thing is that the decision was conscious.

If you have ever been interested in the device of the camera, then you have probably heard the term "full-frame" camera. Many photographers rave about cameras with large sensors, arguing this for a number of reasons. Today, we'll take a quick look at why so many photographers choose these cameras, and what exactly are the benefits of a full frame.

Matrix size overview

To understand what full frame means, it is necessary to look back in time and consider the basics of image creation. Throughout the existence of cameras, various sizes of matrices or films have been used.

The sensor is the part of the digital camera that is responsible for the formation of the image. When the camera shutter opens, the matrix begins to capture and recognize the image and continues to do so until the moment.

The Canon 5D has a much larger full-frame sensor than classic APS-C DSLRs.

With film cameras, the role of the "sensor" was performed by a separate exposed frame of the film. The most popular size in the pre-digital era was 35mm wide film. Full-frame cameras are cameras with a sensor that is the same size as 35mm frame film cameras.

Before the advent of full-frame cameras, it was mostly the smaller sensors that were used. Nikon simply refers to these cameras as DX, and the term "APS-C" can also be seen, but it is applied to digital SLR cameras with a slightly smaller sensor. Photographers usually refer to such cropped-sensor cameras as “cropped-sensor” cameras or say that the camera has a “cropped sensor”.

In "soap dishes" and mobile phones even smaller matrices are used.

Benefits of Full Frame Cameras

Amid all this talk about sensor sizes, the question arises why many photographers give their preference to a full frame camera, what are the advantages of a full frame? It turns out that cameras with a smaller sensor size can only dream of the advantages that full frame cameras have.

Their main advantage is more high quality Images. The larger the matrix, the better the camera recognizes details.

As we mentioned above, mobile phones and soapboxes have the smallest matrix sizes. Manufacturers are trying to solve this problem, to improve the quality of the image received by the cameras of mobile phones and point-and-shoot cameras, but it is unlikely that in the near future it will be possible to achieve the image quality of these cameras comparable to the quality obtained on full-frame cameras.

In addition, cameras with large sensor sizes tend to have better . This means they perform better in poorly lit environments, giving you more room to work in those situations.

Matrix size visualization

This figure shows the difference in the sizes of different types of matrices:

On small cameras, the so-called "crop factor" is clearly expressed in terms of the focal length of the lens. The main difference between a full frame and a crop is the size of the image space that falls into the frame:

a larger matrix captures more space in the picture.

On full-frame cameras, a 50mm lens provides a "normal" image at medium ranges, while on smaller sensors, the same lens will have a telephoto or zoom effect. The image looks like it has been cropped or truncated around the edges, hence the name crop sensor.

Go to full frame

If you are planning to switch to full frame, then for a start, I would recommend not buying a fancy camera. latest model, and find yourself something simpler and a little older and, preferably, in the market for used photographic equipment. Previously, a huge barrier to purchasing a full-frame camera was its cost.

Currently, this problem does not exist, since the Canon 5D is now available for about $ 700 or even less, and Nikon's D700 is also falling in price. Each of these cameras does not necessarily have latest features, but they both provide quite decent image quality.

Canon's full-frame 5D can be purchased for under $700 on the used market and is the least expensive option when moving to a full-frame digital camera.

When switching to the camera from big size sensors should also take into account the cost of purchasing full-frame lenses. After all, not all lenses that you wind on your "cropped" camera are suitable for use on a full-frame camera.

The cheapest way is to choose a set of simple prime lenses. Both Canon and Nikon have f/1.8 lenses across the spectrum that are not only effective in low light, but have good sharpness, just as good as expensive lenses.

Before discarding my old cropped lenses, I would advise you to check in practice whether they will work on your new full-frame camera. Surely one of them will fit.

Conclusion

Full frame cameras are becoming more and more popular and their prices are dropping, especially in the used camera market. Now, having considered all the advantages of a full frame, it becomes clear why many professionals prefer this particular type of camera.

In this article, we will discuss a few myths and the advantages and disadvantages of a full frame sensor and explain how it can affect Various types photos. We will also look at ways to fine-tune your shooting equipment so that you can full force use your full frame camera.

For good examples here we used a full-frame Nikon D600 and Nikon with an APS-C sensor. We will not go into the unique specifications of each camera manufacturer, as this may seem confusing and distract you from the discussion on our topic. But the principles discussed below will apply equally to full-frame DSLRs from Canon, Sony, Leica, or any other brand.

What is full frame?

"Full frame" is a term used to describe cameras that have the same sensor size as a 35mm film camera with a size of 36mm x 24mm. But most DSLRs use a sensor that is about 24mm x 16mm.

This is close to the APS-C aspect ratio, which is why they are often referred to as APS-C format cameras. Nikon makes cameras in both sizes, but uses its own designations. Its full-frame models are designated "FX" and its APS-C cameras are designated "DX".

Initially, almost all DSLRs used the smaller APS-C format. Sensor technology was in its infancy and large sensors were too expensive to produce.

Full-frame cameras have become less expensive over the past few years, and while the Nikon D3, D3s and D3x are offered to consumers at the price of professional DSLRs, the Nikon D800 and D600, released in 2012, cost much less. The price for them is still not low, but they are more affordable.

Nikon full frame sensor

The bigger, the better

In the days of film photography, it was believed that the larger the negative, the best quality you get an image. The same applies to digital sensors. The full-frame Nikon FX sensor is one and a half times wider than the DX format sensor. This affects the quality of the photos.

In general, pictures taken with a full-frame camera are sharper, with more detail, smoother midtones, a wider tonal range, and a greater sense of "depth."

Therefore, more and more enthusiasts and photography enthusiasts will be thinking about switching from a Nikon (or any other brand) DX-format camera to a full-frame model.

Despite the improved quality, which is easy to demonstrate, there are also disadvantages. Mirrored Nikon cameras DX formats are not only cheaper, they are in many ways easier to use and more practical.

Lens compatibility with full frame sensor

Another question that pops up when moving to full frame is with lenses. You can have one camera body today and another tomorrow, which cannot be said about a lens that can be considered a long-term investment. Years ago you could buy a Nikon D50 and it might be outdated, but the lens you got back then hasn't lost its relevance.

Nikon, along with the release of digital reflex cameras DX-format set up for them the production of a number of DX-format lenses. So if you decide to go full-frame FX, then you will definitely have to invest heavily in new lenses.

You can use DX-format lenses on an FX camera, but only in crop mode. The camera limits the area of ​​the sensor being used to a DX size box in the middle, so you don't benefit from the sensor's full resolution.

For example, in crop mode, a 36-megapixel D800 will produce 15.3-megapixel images. In this case, the 16-megapixel D600 will reduce the resolution to 6.8 MP. Thus, DX lenses are not particularly promising.

Of course, you may already have some FX lenses, such as Nikon's 70-300mm f/4.5-5.6 telephoto zoom, which is popular with owners of DX-format SLRs, when it's actually an FX format lens.

If you're thinking about switching to an FX camera in the future, start investing in FX-format lenses now because they will work on any Nikon DX-format SLR. The image below clearly illustrates what happens when you combine a sensor and a lens of different formats.

crop factor

Other a big difference between DX and FX formats is what they mean by lens angle. The DX sensor captures a smaller area of ​​the image, so it looks like you're using a longer focal length lens.

If you mount a 50mm lens on a DX camera, your photos will look like they were taken with a 75mm lens. This is the so-called "crop factor". Photographers also refer to it as "equivalent focal length", but it's actually the same thing.

Nikon's sensor's DX crop factor is 1.5, which means you multiply the actual focal length of the lens by 1.5 to get the equivalent focal length.

This can work in your favor with DX cameras. For example, if you have Nikon lens 300mm at f/2.8 that's on the D7000, it actually becomes 450mm at f/2.8!

If you upgrade to a full frame camera like the D800 in the future, your 300mm f/2.8 lens will still work just fine as a regular 300mm.

There are many things to consider when choosing between DX and FX formats, including practical and technical considerations.

Why is the depth of field different?

Theoretically, lenses should give the same depth of field on both FX and DX format cameras, so why would FX cameras produce less out of focus backgrounds?

Typically, on an FX camera, you need to stop down about 1/3 stop to get the same depth of field as with a DX-format camera.

Why is this happening? Because you are not actually using the same lens on both cameras. The smaller sensor on the DX model means you can use a shorter focal length to get the same angle of view.

For example, if you are using a 50mm lens on an FX camera, then on a DX camera you need to mount a 35mm lens to get the same angle of view - and the 35mm lens will give you much more depth of field due to its short focal length.

How to shoot with a full frame sensor

You need to improve your shooting technique to properly take advantage of the full frame sensor. Here's how to do it.

Investment in lenses
You will lose the advantage of wide sensor resolution if you use old or cheap lenses. good choice there will be Nikon's new 24-85mm VR, or 24-70mm f/2.8.

Focusing
The focus point is critical to using extra resolution. Manual focus is not always accurate enough, autofocus may be more accurate.

Aperture setting
You need one stop less aperture to get the same depth of field as a DX camera. Avoid apertures smaller than f/11 because diffraction will affect sharpness.

"Safe" shutter speed
Instead of 1/30s with a 30mm lens, try using 1/60s or even 1/125s for example.

Use a tripod
To ensure maximum sharpness in the image, use a tripod. Choose a quality one, it will not only be durable, but also reduce vibration from cars and people moving past.

Memory improvement
An 8 GB memory card may be sufficient on your 16 megapixel DX-format camera. But in the D800, it is only enough for 103 uncompressed RAW files.

How does a full frame sensor affect your photos?

Increasing the sensor size to full frame affects appearance your photos. It's about not only about megapixels.

1. Image quality
Full-frame photographs tend to have more detail and more dynamic range than images taken with a DX-format DSLR. With a good subject in the right shooting conditions, the quality advantage becomes clear.

2. Feeling of depth
The shallow depth of field that you get when shooting with a full-frame camera adds a strong sense of depth to the photo. It can prevent you from getting the maximum depth of field that you are aiming for, for example, in landscape photography.

More and more amateur photographers are now turning their attention to cameras with full-frame sensors, which should provide better image detail, smooth transitions in the midtone zone and a greater sense of “depth”. However, a wide variety of myths and misinformation are associated with full-frame matrices. What are the main features and advantages of cameras with a full-frame sensor, and is it worth changing a regular camera with a crop sensor to an expensive full-frame model? We will talk about this in this article.

Full frame sensor

But first, let's define what a "full frame" is. We are talking about the physical size of the photosensitive matrix used in digital camera. She, as you know, is responsible for the quality of the image. Full frame cameras are those that have the same sensor size as a 35mm film camera with a size of 36 x 24mm.

At the beginning of the development of digital photography, almost all devices had a light-sensitive sensor of a smaller format due to the emergence of technology and the too high cost of producing full-frame sensors. However, over time, the production of full-frame sensors has become less expensive, which has allowed leading manufacturers to offer full-frame cameras to users.

Although the price for them cannot be called low today, nevertheless, such full-frame cameras have become much more affordable. Examples of full-frame cameras are Sony SLT A99 or Nikon D700.

Matrices with a crop factor, that is, with truncated physical dimensions, are commonly referred to as APS-C sensors. Nikon, however, uses its own designations: "FX" for full-frame models and "DX" for cameras with cropped matrices. Typically, a crop sensor is 1.5 to 1.6 times smaller than a full-frame sensor. However, today cameras are produced with matrices having a variety of physical sizes.

Naturally, the majority of cameras with truncated matrices are in mass sale, they are cheaper and more convenient for beginners. If you shoot an image with a normal full-frame lens and superimpose it on a cropped sensor, then the image at the edges will be cropped by about thirty percent, that is, it will be one and a half times smaller. The number 1.5 is called the crop factor. Each manufacturer of photographic equipment has its own, but on average it varies within exactly 1.5 - 1.6.

As we know, back in the era of film photography, it was generally accepted that the larger the negative, the better and more detailed the image will be. A full-frame sensor is on average one and a half times wider than an APS-C sensor and, of course, this cannot but affect the image quality. What are the benefits of full frame?

Features and Benefits of Full Frame Sensors

First of all, a feature of cameras with full-frame sensors is the viewfinder scale, which is noticeably larger than that of conventional cameras with a cropped sensor. This, in turn, provides excellent opportunities for convenient selection of shooting parameters and angles. But the most important advantage of full-frame sensors is, of course, the possibility of obtaining clearer and quality pictures at high ISOs, with much less digital noise.

Large full-frame sensor allows you to "shove" into it large quantity photocells, and even larger, which has a positive effect on the perception luminous flux. Therefore, for the same number of megapixels, a full-frame camera will always provide better results at high ISO values ​​than a conventional crop sensor camera. You have the opportunity to seriously increase the ISO value when shooting, while you do not have to worry that the noise in the image will become visible.


The difference between a full-frame sensor and a crop sensor also shows up in the effect of increasing the focal length. The cropped sensor captures a smaller area of ​​the image, so the final picture looks like you were using a lens with a longer focal length. That is, on crop, the equivalent focal length increases in proportion to the crop factor.

For example, if you use a 50mm lens on a camera with an APS-C sensor, your photos will look like they were taken with a 75mm lens (crop factor = 1.5). That is, in the case of APS-C cameras, increasing the equivalent focal length can work in your favor. It is impossible to talk about the unequivocal advantage of a full-frame camera here, because everything depends solely on what you are going to shoot. Someone needs a full-frame camera to shoot a wide perspective, and someone wants to achieve a closer approximation of the objects being shot, and therefore it is more expedient for him to use a camera with a cropped matrix.

Shooting with a full-frame camera adds a strong sense of depth to images. This effect is achieved due to the shallow depth of field. As a general rule, on a full-frame camera, you need to close down the aperture by about 1/3 stop in order to get the same depth of field as with a camera that has a crop sensor. In optimal shooting conditions, full-frame cameras are also able to provide images with better detail and greater dynamic range due to the increased number of light sensors.

However, all these advantages of full-frame cameras are offset by the use of old or cheap lenses with them. If you decide to upgrade to a full frame camera, be prepared to invest heavily in new lenses that are compatible with full frame. You should pay attention to the optics that can convey all the advantages of a large sensor. The use of cheap and low-quality lenses negates any improvement in image quality that a full-frame sensor can bring with it.

Each manufacturer of photographic equipment currently produces optics separately for full-frame cameras and cameras with truncated matrices. For example, EF-S and EF lenses can be mounted on Canon amateur cameras, the choice of which is very diverse. For full-frame models, a limited set of EF optics is provided. That is, for a full frame, the available optics park is less.

But some of these lenses have characteristics that are almost inaccessible to the crop. Accordingly, specialized and high-quality optics for full-frame cameras can really emphasize all aspects of the performance of large high-resolution sensors.

Disadvantages of full frame cameras

As already noted, the effect of changing the focal length on crop matrices can be a serious advantage for the photographer and a decisive criterion when choosing photographic equipment. All you have to do is take a 300mm f/2.8 lens and mount it on a crop sensor camera and you actually get a 450mm f/2.8 lens.

That is, the crop factor allows you to achieve an increased reach of the lens with significant savings. Therefore, conventional crop-sensor cameras can be very useful, for example, when shooting animals in natural environment habitation, photographing sports competitions or reportage photography.

But the main stumbling block is still the cost of full-frame cameras. Models with full-frame sensors are still much more expensive than conventional ones, and therefore the question invariably arises as to the advisability of buying them. Full frame cameras tend to be the flagship products of any leading camera manufacturer. The acquisition of such equipment always hits the pocket. Moreover, when buying a full-frame camera, you will most likely have to buy additional lenses, because not all optics from crop cameras are compatible with full-frame cameras, and vice versa.

Due to the high cost, buying a full-frame camera for amateur photography is unlikely to be appropriate. For professional photographers, the advantages of a full frame compared to the cost of a camera are much more justified. In addition, experienced photographers know better how to properly use the features of a full frame sensor. Amateur photographers will have to improve their shooting technique when switching to full frame.

So, "full frame" due to the increase in the size of the receiving cell reduces the noise level at high ISO sensitivity, expands the dynamic range and increases the image detail. In addition, the lens on a full-frame camera gives a wider field of view, which can be required in many shooting situations. But if you decide to change your camera to a camera with a full-frame sensor, you should clearly understand for what purposes you will need it. Before buying a "full frame"

You also need to make sure you have compatible lenses so that you can take full advantage of your new camera. Beginning photographers often make a huge mistake by investing their entire budget in buying a more perfect and advanced camera, completely forgetting that it is not the camera that shoots, but the lens.

Full-format Nikon and Sony cameras (maybe others) can work both in the usual full-format mode, when the entire sensor of the camera is used to obtain an image, and in crop mode. For example, you can use the APS-C crop mode (DX for Nikon). In this mode, only the central area of ​​the camera's sensor is used. The size of this area exactly corresponds to the size of the matrices on cropped APS-C cameras. To put it simply - full-length cameras can be made to 'work crop'.

The ability to shoot in crop mode allows me to personally manipulate the equivalent focal lengths (EFF) a little. For me, this turned out to be a very nice feature when shooting with prime lenses.

An example of using crop mode: I often shoot events with a fast fifty-fifty lens and a full-frame camera. Sometimes I can't get close enough to my subject, so I turn on crop mode. To do this, in the camera menu, just turn on the 'Image area'-> 'Select. image area 'and select the value there 'Format DX 24 x 16'. In the “AF Point Illumination” setting, I have “Off” selected, which allows, after turning on the “DX Format 24 x 16” function, to darken the unused area of ​​​​the image visible in . In fact, in the optical viewfinder, I only see the image that I get after the shutter is released. Visually, it seems that the lens turns from a 50 mm fix into a 75 mm. This trick makes it easier to frame the future frame, to reach more distant subjects.

Of course, I am well aware that exactly the same result can be obtained while cutting out the central part of the photo during processing (the result will be 100% similar to what I get with the 'Format DX 24 x 16' function). But psychologically it is much more convenient to build a frame directly during the shooting.

WITH electronic viewfinder even simpler - there you immediately see the image obtained from the central part of the sensor without darkening the areas in .

Closer to the point

So, switching between FX formats<->DX and shooting the same scenes with the same lens, I noticed that sometimes the blurring of the far and near ground in the DX format looks (visually looks) stronger than in the full FX mode.

It should be just the opposite! We all know the story about the fact that full-frame cameras blur the background more strongly. How then to be?

Look at the next two shots and note for yourself where the background blur is stronger. Blurring refers to the size of circles of confusion.

First picture:

Original shot from Sony a7II camera. The picture has a lot of circles (discs) of blur

Second picture:

Original from a Sony a7II camera in APS-C mode (actually - cutting out the central part of the previous picture)

Visually, the blur zone in the second image is more pronounced, and the discs of blur are larger. At the same time, the second picture, roughly speaking, was taken on a crop. This happens if you shoot from the same distance without maintaining the proportions in the frame.

Let's take a separate pronounced disk (circle) of blur.

From the full size photo:

Blur disk in full size image

From the cropped photo:

The selected blur disk in the pictures has the same size in pixels.

A full-size photo taken with a Sony a7II is 6000 x 4000 pixels (24,000,000 pixels). The area of ​​the circle is Pi*D*D/4 and equals 54.297 pixels. In this case, the size of the circle is 1/442 of the image of the entire image (0.23%).

The cropped shot from the Sony a7II is 3936 x 2624 pixels (10.328.064 pixels). The area of ​​the circle is Pi*D*D/4 and equals the same 54.297 pixels. In this case, the size of the circle is 1/190 of the image of the entire image (0.53%).

When switching from a full-length shot to a cropped one, the ratio of the blur disk to the entire frame increased by approximately 2.3 times. The same number could be obtained thanks to the coefficient Kf=1.5, squaring it.

A serious conclusion: if you shoot on cropped and full-length cameras to the same lens, at the same value and from the same distance, then due to different proportions of blur zones.

Spoiler 1: different cameras of the same type (crop or full frame) different amount megapixels, but the ratio of the blur disk to the entire frame will be the same.

Spoiler 2: I was asked to do an experiment with a point light source placed at infinity. I did not do this, because the experiment can not be considered 100% honest. You can conduct your own investigation of circles of blur at infinity yourself.

Spoiler 3: in the article, I show images reduced to the same pixel dimensions - 1200 pixels on the long side. This must be taken into account.

Spoiler 3.1: for comparison, crop and full frame shots were adjusted to the same size. The pictures have the same aspect ratio of 2:3, while down scale the pictures look the same.

Spoiler 4: the article is not about DOF. Do not confuse the depth of field and the disc of blur.

Spoiler 5: do not confuse DOF and far/foreground blur force. The depth of field may be the same for two shots, but the strength of the background / foreground blur will be drastically different. To put it very bluntly, DOF is most dependent on the F-number (aperture number), and far/foreground blur is most dependent on the focal length of the lens.

The trick is that the ratio of object size to frame size will change. To shoot the same object, in this case, a twig with berries, with the same scale (so that the size of the twig in the frame is the same on both the full-frame and cropped cameras), in the case of a cropped camera, you will have to move further from the subject being shot than in time of using a full-frame camera.

Test. Get the same full frame and crop shots using the same lens

To maintain the proportions of the object being shot in the frame with a full-frame and cropped APS-C camera, the focusing distance should differ by 1.5 times. The difference in focusing distances is easy to calculate using my calculations.

Very important: the difference in focusing distance corresponds to the factor .

All pictures below were taken with the same ISO settings, and , but with different focusing distances and framing modes (it's the same as shooting with cropped and full-format cameras at the same settings).

The first shot was taken in full frame mode (FX mode), focusing distance is approximately 45 cm (data from ):

The second shot was taken in crop mode (DX mode), focusing distance is approximately 45 cm (data from ). The picture was taken on the same camera, from the same position as the previous photo, just this time the 'Format DX 24 x 16' mode is on (a complete analogy if a cropped camera was used). You can see how zoomed in the shot is:

Let's move the camera away from the object being filmed. The third shot was taken in full frame mode, focusing distance is approximately 60 cm (data from ):

The fourth shot was taken in crop mode, focusing distance is approximately 60 cm (data from ). The picture was taken on the same camera, from the same position as the previous photo, just this time the 'Format DX 24 x 16' mode is on (a complete analogy if a cropped camera was used). You can see how zoomed in the shot is:

Comparison of a picture on a “full-format” camera and a “cropped” camera:

It is clearly seen that the proportions of the object being shot in the frame remained the same (i.e. with the same scale), but the perspective has changed. In the case of the DX mode, the perspective has become narrower (visually felt as an influx of the background). The reduced perspective in the DX image matches that of a 75mm lens used on a full-frame camera.

The change in perspective is clearly visible in the next GIF animation. Notice how in DX (i.e. crop) mode, the background “approaches”, squeezing the perspective:

A small note. Although I indicated that the difference in focusing distance should be 1.5 times to get the same shooting scale, you can see that in this case the difference is 60cm / 45cm = 1.33 times. A small error may be due to the fact that the data may not be recorded accurately. This is indirectly confirmed by the fact that the lens has an MDF equal to 45 cm, but I did not shoot on MDF, since the focus ring was not screwed all the way, at the same time it shows 45 cm. Also, the lens has the Focus Breathing effect - changing the angle view while focusing. Yes, and the pictures, nevertheless, are not quite similar due to lens distortion (at the edges of the full frame they are more noticeable).

A small conclusion that everyone passes by: subject to the shooting scale (the subject being shot has the same proportions in paired shots) to a full-frame camera and to a cropped camera, using the same and the same F number (for example, the same fixed lens with the same F number) visual blur (disks blur zones) on the crop will look larger than on the full frame. Yes exactly! The crop, in fact, will blur the far/foreground more strongly. If you don't believe me, then just take a close look at the GIF animation above. You can visually see how much the blur zone disks of the DX camera are larger than the blur disks of the FX camera. I believe that this is the reason why it is so difficult to distinguish between full frame and crop shots using the same lens at the same value. Photographers psychologically expect a stronger blur on a full-frame camera, but it turns out quite the opposite. The radius of the disc of confusion, in this case, increases by K times, where K is the coefficient . Strange, but everyone passes by this conclusion.

Test. Get the same full frame and crop shots using different lenses (or a zoom lens)

In order for the images from the full frame and the crop to be the same (or very, very similar), you should use different focal lengths and values.

For example, if you take a lens, then the same shots on a full-frame and cropped camera should be obtained, for example, in the following case:

  • cropped camera uses 50 mm focal length and f / 2.8
  • full frame camera uses 75mm focal length and f/4

The following shots were taken at the same focus distance. The camera was always in the same place. Only the exposure and focal length settings changed. The exposure pair (shutter speed/aperture) was changed to compensate and blur strength.

The first picture was taken in full frame mode:

Similar shots

44 mm instead of 50 mm turned out, most likely, for several reasons:

  • perhaps it has not honest 75 mm at the long end, but 70 (like most lenses of this class)
  • perhaps 44 mm of focal length is inscribed in not quite correctly. Who knows how the Tamron chips are programmed
  • most likely, during the test, I still made a slight deviation in maintaining the similarity of the picture

Slightly different pictures turned out due to:

  • different world
  • 2.8 * 1.5 = 4.2, but the camera cannot set the value of F / 4.2, you can only select F / 4.0 or F / 4.5, F / 4.0 is closer to the theoretical calculation
  • different distortion at different focal lengths and framing modes
  • different at different focal lengths and framing modes

All test materials in RAW + JPEG format can be downloaded from this link and you can dig into the material from the article yourself.

Results

  1. The most obvious result. If you shoot the same scene on a cropped and full-frame camera, using a lens with the same focal length, at the same aperture value and from the same distance, then change the zoom level.
  2. Not an obvious result. If you shoot the same scene on a cropped and full-frame camera, using a lens with the same focal length, at the same aperture value and from the same distance, then the blur effect on a cropped camera will look stronger(due to the different scale of the blur zone / disk, see pictures with blur disks). In numerical terms, the strength of the blur increases by a square. As a result, we can say that in such a situation, the crop camera blurs the background more strongly. I noticed this feature during the actual shooting. It is this feature that caused this article to be written.
  3. Focus distance difference between cameras different sizes matrices, when using a lens with the same focal length and maintaining the shooting scale, it corresponds to the coefficient . For APS-C cameras (such as Nikon DX), compared to full-frame cameras, you will have to increase the shooting distance in 1.5 times to maintain the same shooting scale.
  4. Perspective difference. With the same lens on a cropped and full frame camera you can't get the same pictures. due to different rendering of perspective (see the first GIF-animation).
  5. The same frames (as far as possible due to different matrix resolutions and other conventions) from cropped and full-frame cameras can only be obtained on lenses with different focal lengths(see second GIF animation). In order for cropped camera shots to be as close as possible to shots from a full-frame camera, on a cropped camera, you should use a focal length K times smaller than on a full frame, and an aperture number K times smaller than on a full frame. K is the coefficient. In the case of the Nikon DX crop, K = 1.5.

Thank you for your attention. Arkady Shapoval.