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What is a DSLR? [The Beginner’s Guide]

DSLR cameras have been around for a while and they are currently the most used digital cameras around. Evolving from the old school SLR cameras, DSLRs have taken photography to a new level with improved features, convenient controls, and more. Not even just photos, these cameras have been capturing excellent quality videos.

The older Film Cameras used to take nice photos, but the process of capturing the image and getting the photo in your hand was way too long and comparatively more expensive. Going digital introduced a way to store a large number of photos inside a small SD card and view them on a display. You can still get a print-out but, it is completely up to you.

Brands like Canon, Nikon, Sony, Panasonic, Fujifilm, and Olympus have been making DSLRs for some time now, and they have gotten better. These cameras are now more capable than ever and anywhere from the budget to the premium segment, DSLR cameras are thriving right now.

What is a DSLR?

The Digital Single-Lens Reflex (aka DSLR) cameras are digital photography cameras operating on optical core elements instead of relying on electrical ones. There is a proprietary lens mount, a sensor below that, a physical shutter, a reflex mirror to reflect the image input, a prism mechanism to correct the inverted orientation, and an optical viewfinder.

The setup is pretty much what older SLR cameras were like, but instead of a film, you store your photos on a memory card and can transfer the same to a computer. Newer models also come with Bluetooth, Wi-Fi, and NFC. You can also get a smartphone app to transfer your photos over the air or to control your camera remotely.

How Does a DSLR Work?

As mentioned earlier, DSLR cameras are pretty similar to SLR cameras. That means it uses the same optical setup as well. Everything from the optics inside the lens to the optics inside the camera come together as one to pass on the visual to the sensor and to your eye. Of course, all the digital factors are there as well.

Optical Elements of DSLR
Optical Elements of DSLR

When you attach a lens to a DSLR camera, the optical elements inside the lens take the visual and pass it on to the sensor. The sensor captures the visual data and sends the same to the image processor which then constructs the final RAW image. If you are shooting in a non-RAW format (e.g. JPG), the camera also converts the RAW image to that format and adds the required color science to get the final image. Of course, there is also the shutter that opens and closes depending on the shutter speed settings on your camera.

Now, there is a second set of optical elements working at the same time. The visual passed on by the lens also gets reflected on a mirror that then passes that on to a prism element. The prism corrects the orientation of the visual (image) as that would be upside down before that point, and sends it to the optical viewfinder.

All the major controls are built into the camera body and there are additional ones in the camera menu. The lens also generally has controls like aperture & auto/manual focus built-in, but there are exceptions. The DSLRs also come with external displays on the back and you store all your photos in SD cards or faster CFast/CFexpress cards in high-end flagships.

Types of DSLRs

DSLR cameras don’t come in form factors but, there are essentially three types to them based on the type of sensor they are using. These include Full-frame, APS-C, and Medium Format. However, Canon also makes APS-H which sits somewhere in-between APS-C and Full-frame.

1. Full-frame DSLRs

Full-frame DSLR

The most comprehensive & prosumer DSLRs in the market in the market, has to be the Full-frame ones. As the name suggests, these have Full-frame sensors in them which means you get the exact focal range of the lens attached.

The camera itself also tends to be a bit on the bigger & heavier side. However, you do get the benefits of a physically bigger sensor including better low-light capabilities and better dynamic range in most cases. Of course, there is also no crop factor, so the.

2. APS-C DSLRs

APS-C DSLR

The APS-C DSLRs are the most common ones in the Digital SLR user base. The sensor is definitely smaller than Full-frame and this time you get a 1.52 times crop. So, whenever you’re attaching a lens, you’re getting a 1.52 times zoom and a 1.52x extended range.

Of course, the APS-C DSLRs don’t match up to their Full-frame flagship counterparts. But, they’ve gotten really good over the years, and in recent times, they can get pretty close in terms of quality.

3. APS-H DSLRs

APS-H DSLR

As mentioned earlier, the APS-H DSLRs are only produced by Canon, and as far as size goes, they sit between Full-frame & APS-C. That also results in a smaller crop factor of 1.29 times instead of 1.52 on APS-C.

Canon’s 1D series of cameras are the only ones coming with APS-H as of now. The physical size of these cameras are kinda gigantic

4. Medium Format DSLRs

Medium Format DSLR

The Medium-format DSLRs house the largest sensor available in consumer photography and they also cost a lot. The sensor crop factor is 0.64 times which means it zooms out instead of zooming in. That’s results in an even wider field of view than Full-frame.

The most common type of DSLR cameras found on the market are APS-C and Full-frame. The other two are pretty rare. Also, Micro Four Thirds sensors aren’t used in DSLRs, so you’re not gonna found any DSLRs in one of those smaller form factors similar to Mirrorless.

Advantages & Disadvantages of DSLR

DSLR cameras are excellent tools for shooting photos and videos. However, like every other gadget, they do have their own set of advantages and disadvantages. Here are a few that matter:

Advantages
  • If you shoot with the optical viewfinder, you can get insane battery life because the viewfinder isn’t using additional power.
  • DSLRs aren’t made with 4/3 sensors which means the maximum crop goes up to 1.52x (APS-C)
  • For beginners, just going into photography, there are a lot of cheap DSLR options available to start with.
  • Because DSLRs have been out there for a very long time, lens availability is often better and the lenses even come cheaper most of the time.
Disadvantages
  • In most cases, DSLR cameras are heavier and less compact. That makes it considerably harder to carry around compared to a Mirrorless or a Point & Shoot.
  • DSLR cameras often don’t get the latest and greatest features in budget and mid-range options. You have to get the flagships to get them.
  • The max FPS for shooting photos is often lower on a DSLR compared to a similarly priced mirrorless because of the physical shutter.

How different are the optics in DSLR & Mirrorless Cameras?

DSLR cameras use a complete optical system making the lens and the camera optics working together. The sensor catches up on the image passed on from the lens elements and the mirror also reflects it to the prism element to make orientation corrections which then goes to the optical viewfinder. And of course, there is a physical shutter.

Now, Mirrorless cameras still use the lens elements the exact same way, and the image processing is still done by the sensor and the processor, but the viewfinder is electrical (a tiny display), so there is no Mirror-Prism mechanism. The Shutter is also electrical, which means that it isn’t a physical one.

Mirrorless Camera vs. DSLR

In most cases, Mirrorless cameras are less bulky and more compact compared to DSLRs. Also, the most common sensor in Mirrorless is Micro Four Thirds but, they are also available in APS-C and Full-frame. Unlike DSLRs, there aren’t any Medium format or APS-H Mirrorless cameras made as of now.

DSLR vs Mirrorless

You do however get better battery life on DSLRs if you are using the viewfinder. As Mirrorless cameras have displays for viewfinders, they use up a chunk of the battery so, it’s isn’t even close to DSLRs. However, if you are using the display on the back, the battery life is pretty much the same.

Things to Consider When Purchasing a DSLR

Now as you have a good idea of what exactly a DSLR camera is, its functionalities, and how it differs from Mirrorless cameras, here are a few things that you need to keep in mind when purchasing a DSLR camera:

  • Make sure you’re getting a current model with a new sensor and a new image processor inside.
  • The camera needs to have good autofocusing as that’s what you’ll be using most of the time.
  • Having a good Shutter Speed range (e.g. 1/8000-30 seconds) and a good ISO range (e.g. 50-256000) matters, especially if you’re buying a pricey camera.
  • No matter which DSLR you end up getting, it should have good battery life and replacement batteries should be easier to find in the market.
  • If you’re going to shoot videos, make sure the device has at least 4K 30FPS and 24FPS. In flagships, 4K 60FPS and 1080P 120FPS (slow-mo) are necessary. 
  • A microphone jack is also necessary for videos and if there is an additional headphone-out jack, that’s a plus.
  • For filming or taking photos of yourself, a flip-LCD display is needed.
  • Having two memory card slots and support for faster CFast/CFexpress cards is a plus for flagships and upper mid-rangers.
  • Depending on if you want a crop factor or not, make your purchase decision. If you don’t need a crop go for a full frame, if you don’t mind the 1.52x crop, get an APS-C and save some money.
  • If you plan on shooting handheld, it’s better to get a lighter camera. That allows you to shoot for longer periods of time.

Depending on your budget, you have to mix and match from this wishlist, and if you have all pointers in check, you’ll end up with a great DSLR camera to shoot photos and videos with.


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