A Primer For The Modern DSLR

by William Lulow

This year, in 2026, I had a student who enrolled in one of my classes who wanted to learn more about his digital camera. This was someone who had plenty of experience with cameras and film, but needed more training in the use of digital equipment, so I thought I would go over some elements of digital cameras. Although I have been “digital” since about 2001, I keep learning more about the capabilities of today’s sensors and other camera controls and settings which continue to improve. I have been incorporating all the new knowledge in my current crop of lessons.

This is a recent digital image from my granddaughter’s swim meet. The settings for this image were ISO 10,000, aperture of f/4.5 and a shutter speed of 1/1250th of a second. These settings were required because of the low light levels and the speed of the action:

These days, the digital process is completely interwoven with the modern computer. You need a computer to be able to get a good idea of what you shoot with your digital camera. Digital cameras work by recording scenes digitally (with ones and zeros) on a “card” which can be a COMPACT FLASH CARD or smaller sized SDHC or SDXC ones. Each is capable of storing digital information, so it is a matter of which one the particular camera you like uses and the requirements of your assignments . These cards are available in many capacities from 4GB to 128GB and more, if you use the SDXC ones. The size of most images these days, is measured mostly in megabytes (MBs). For comparison, a one page typed document takes up about 250 BYTES.

A KILOBYTE (KB), is 1,000 bytes. (Roughly equivalent to 4 typewritten, 8.5×11 pages.) A MEGABYTE (MB) is 1million bytes. A GIGABYTE (GB) is a billion bytes. And, a Terabyte is 1 trillion bytes. (I have several external drives each holding 2TB of storage space. Typically a photoshoot consisting of about 100 images recorded on an SDHC card would take up roughly 1-3 GB of space. I use a 64GB SDHC card most of the time so I am able to put several jobs on this card although I usually erase the card after each “job.” A JOB consists of anything I shoot at a single outing, whether it’s a commercial assignment or just some images for myself, as on a trip, say. A large portrait shoot, for instance, (one in which 10 or 15 headshots would be made) might take up about 8 or 9 GB of space on the card. So you can see, that a 64GB card would be sufficient for really large jobs. (The SDXC cards have capacities up to around 2TB). As a matter of fact, I usually pack two cards with me on most jobs, just in case. On a trip to Italy last year I shot roughly 1,500 frames that took up about 16GB on that 64GB card. This capacity is way more than anyone would need for most photographic outings. As a matter of fact, one entire, busy year’s shooting, every single frame, occupies about 150GB on one of my 2TB (Terabyte) external hard drives.

(Note: these numbers are based on shooting full JPEG images at the highest resolution my cameras can handle. Many photographers like to shoot RAW images, which substantially increase file sizes. Most of my work needs to be transmitted to my clients over the internet. So, clients would need all the software that I use in order to view any RAW files. In addition, due to the large size of the files, transfer would take much longer. I get superb results shooting in JPEG format. I see no reason to use the RAW format unless it is specifically asked for by an art director.)

After you are finished with your shoot, you will need to download your images to your computer. I still use a PC, having started with them back in 1983 to run my studio’s mailing list. The comparable Apple machines in those days were three times the price, even though I thought they were superior to the IBM machines. By the way, Microsoft, (Bill Gates’ company) made megabucks trying to make the PC look like an Apple machine. They invented what’s called a GUI (Graphic User Interface) because typing everything you wanted a computer to do by hand was way too time-consuming. Nowadays, the PC can do everything the Apple can, but I think the Apple is still a superior product.

You have to realize that image files are large, as I have described, so you need a computer that’s fast enough in processing speed and has enough memory (RAM) to handle these files. My setup consists of:

• A computer with a processing speed of at least 2.9megaherz
• 16MB of RAM (Random Access Memory)
• 5 External Solid State Drives (SSDs) for image storage
• A 27 inch monitor
• 3 printers (One color printer that can print up to 13×19″ prints)
• 1 Flatbed scanner
• Numerous other tools that plug in to the computer via USB connections

The speed of the computer plus the right amount of memory will make processing images faster and easier. It is a major consideration for the digital process. The reason for the external drives is REDUNDANCY! It is the easiest way to ensure than your files are permanent! I have most of my files backed up to two different drives including an iCLOUD ACCOUNT. There are RAID systems which are a “REDUNDANT ARRAY OF INDEPENDENT DISKS” which automatically copy everything you save to two or more external disks. Here’s a desktop component for a RAID system. You would also have to buy the disks of course:

All this being said, most of us have come to realize that digital cameras now handle everything as far as exposure is concerned. With film cameras, there was no autofocus. All focusing chores were manual. You would set the film speed you were using into a handheld light meter or the one built into the camera and adjust your aperture on the lens itself and the shutter speed on the camera body. Now, everything is handled with the camera. There are a number of menus that enable you to change settings as well as a number of different MODES to which the camera can be set. Typically, these include:

• MANUAL MODE – The photographer sets all of them manually
• Av MODE – Photographer sets the APERTURE. All other settings are done by the camera
• Tv MODE – Photographer sets the SHUTTER SPEED. All other settings are done by the camera
• VIDEO MODE – Camera can record live video
• PROGRAM MODE (P) – The camera makes decisions on all exposure components except ISO setting
• AUTO MODE – The camera makes all exposure decisions.

In addition to handling everything exposure-wise on the camera itself, there are many more options available to the photographer in the various digital menus built in to most digital cameras.

• A PICTURE STYLE menu which is capable of various user-activated settings to help with the kinds of exposures you might make including a MONOCHROME setting for Black&White images (I call “original B&W).
• A choice of FUNCTIONS including a high-speed shutter setting
• A way to control EXTERNAL FLASH UNITS
• An ERASE TOOL that lets you selectively erase data you’ve saved to your SDHC disk.
• An AUTOFOCUS tool that allows you to set the areas of an image you want.
• A MULTIPLE EXPOSURE setting

These are just a few of the many settings a DSLR offers. So, whoever said that digital photography was easier needs to rethink things a bit. Here’s a medium-end, excellent digital camera with a “kit” lens attached:

All SLRs have a prism on the top which serves to re-orient images to be recorded on the camera’s CARD. The reason for this is that when lenses bend light rays to focus them on a sensor or film, the images are always upside down and backwards, as they were in older VIEW CAMERAS (the ones where you needed a focusing cloth over your head). Today, they are making MIRRORLESS DSLRs which do this electronically, so there is no need for a prism of mirrors, thus making the cameras much lighter in weight:

I have detailed various possible settings with these digital cameras in other articles, so I won’t go into them here. But suffice it to say that once you master the controls and learn where to change your settings on any digital camera, your photography will improve dramatically. There are many lower end digital cameras on the market that rely on MENU ADJUSTMENTS to alter the settings. These you need to avoid if you can. The higher-end cameras have separate dials for each control, which is much faster and easier to use. That’s why they cost more.

The information presented here will help anyone just getting started with the digital process learn the various camera settings and how to control them.