Nikon D3100 vs Olympus E-620: An In-Depth Comparison for the Discerning Photographer

Choosing between two entry-level DSLRs often boils down to subtle differences that can hugely impact your shooting experience. I've spent years testing cameras and lenses, and having spent proper hands-on time with both the Nikon D3100 and Olympus E-620, I want to share practical insights to help you choose what fits your photography style and ambitions.

Both these cameras target beginners stepping into interchangeable lens photography but come from different design philosophies and ecosystems. Let’s dive in.

First Impressions: Size, Handling, and Build

Ergonomics and handling are the first things you’ll notice when picking up a camera - you want something that feels just right in your hands for the kind of photography you do. The Nikon D3100 sports classic DSLR dimensions with a moderately deep grip and reassuring weight of 505 grams, whereas Olympus takes a slightly more compact approach with the E-620 at 500 grams but noticeably thinner front-to-back.

The D3100 sits chunkier, offering a more substantial feel that provides stability - especially helpful if you shoot telephoto or macro. On the other hand, Olympus’s E-620’s slimmer body lends itself wonderfully well to street, travel, or any scenario where lightweight gear is preferred.

I personally prefer the grip and button placement on the Nikon, especially if you pair it with some of the larger Nikkor lenses. However, Olympus’s fully articulated 2.7-inch touchscreen (though not touch-sensitive) is a gem for creative angles and vlogging, outweighing its smaller size.

Both cameras sport durable plastic builds without weather sealing, so neither is an upgrade if you plan to shoot in harsh conditions - important if you’re a landscape or wildlife shooter.

Navigating Controls: Interface and Usability

Functionality without frustration is a photographer’s mantra. The Nikon D3100 and Olympus E-620 both come with optical pentamirror viewfinders covering 95% of the scene, but differ slightly in magnification - 0.53x for Nikon and 0.48x for Olympus.

Nikon’s control layout is clean and beginner-friendly. It has tactile physical dials for shutter speed and aperture priority modes, which I find helpful when learning manual exposure adjustments - especially on the fly. ISO control, exposure compensation, and burst mode buttons are logically placed.

Olympus uses a slightly more cluttered layout because of its smaller body, and some important controls like ISO adjustments are buried in menus. The E-620’s articulated LCD shines here for angle flexibility but lacks touch input, which feels dated for 2024 expectations.

The fixed 3-inch 230k-dot TFT LCD on the Nikon is a bit larger and offers easier viewing in bright daylight when compared side-by-side with Olympus’s 2.7-inch HyperCrystal LCD. For live view focusing, I find Nikon’s screen a bit sharper.

Sensor Technology and Image Quality Analysis

At the heart of every camera is its sensor and processor setup, which define image quality across lighting conditions. The Nikon D3100 sports a 14MP APS-C CMOS sensor sized 23.1 x 15.4mm with an EXPEED 2 processor. Olympus’s E-620 houses a 12MP Four Thirds CMOS sensor, measuring 17.3 x 13mm and powered by the TruePic III+ engine.

The striking technical difference here is the sensor size. The Nikon’s APS-C sensor area (approximately 356 mm²) is about 58% larger than Olympus’s Four Thirds sensor (225 mm²), resulting in better noise handling and dynamic range. The D3100’s higher DxO Mark scores reflect this as well - achieving an overall score of 67 compared to 55 for the E-620.

In practical terms, Nikon captures deeper colors, better shadow detail, and less noise at higher ISOs. This makes it preferable for portraitists seeking natural skin tones or night shooters who push ISO beyond 1600. Olympus’s smaller sensor somewhat limits dynamic range and low-light performance, but it does produce vibrant colors, partly due to its sensor design and processing.

That said, the E-620’s image resolution maxes out at 4032 x 3024 pixels (about 12MP), slightly lower than Nikon’s 4608 x 3072 pixels (14MP). While a 2MP difference may seem minor, that extra detail can help landscape or product photographers who desire large prints or cropping flexibility.

Autofocus System: Speed, Accuracy, and Tracking

Whether you’re capturing a fleeting expression or a fast-moving bird, autofocus performance can make or break your shot. Two major considerations here: number of focus points and autofocus technology.

The Nikon D3100 provides 11 AF points, with one cross-type sensor that improves accuracy, especially in low contrast situations. The Olympus E-620 has fewer points - 7 AF points - but the exact nature of cross-type sensors isn’t published.

My hands-on tests under various lighting show the Nikon consistently locking focus faster and tracking subjects better, especially outdoors and when using phase-detection AF through the optical viewfinder. It also supports AF face detection and live view contrast detection, which performs reasonably well but isn't snappy.

Olympus’s E-620 suffered slower AF acquisition in low light, partially due to its contrast detection relying heavily on the sensor chip. It lacks continuous autofocus tracking in live view, which the Nikon supports. So, for action, sports, or wildlife photography, Nikon stakes a clear claim.

Burst Shooting and Shutter Speed

Speed isn’t everything, but it’s important for wildlife and sports photographers. Nikon’s D3100 can shoot bursts at 3 frames per second (fps), max shutter speed 1/4000th sec. Olympus E-620 is slightly faster at 4fps with similar max shutter speed.

While Olympus has a slight edge there, in my experience the D3100’s autofocus and exposure metering capabilities ensure a higher keeper rate per burst. The 3fps is nothing to scoff at for an entry-level DSLR.

Video Features: Capabilities and Usability

If video is in your plans, the Nikon D3100 outshines Olympus’s E-620, which lacks video recording altogether.

The D3100 records Full HD 1080p at 24fps and HD 720p at up to 30fps in MPEG-4 format. Though it lacks microphone and headphone ports, the basic video functionality is solid for casual creators and beginners getting their feet wet.

I appreciate Nikon’s inclusion of manual exposure controls during video and the option for live view autofocus, which help create smoother footage.

Olympus E-620, while strong on stills with stabilisation (more on that next), sadly offers no video mode, which I find limiting if you prefer a hybrid shooter.

Image Stabilization: Optical vs Sensor-Based

One notable advantage of the Olympus E-620 is its sensor-based image stabilization (IS), uncommon among DSLRs at its time.

This means shake reduction happens inside the camera body, regardless of lens used, improving handheld sharpness in low light and macro scenarios without a tripod.

Nikon D3100 does not have in-body stabilization; it relies on lenses offering Vibration Reduction (VR) technology. While many Nikon lenses support VR, entry-level kits sometimes don't include it, requiring careful shooting to avoid blur.

For macro and slower shutter speeds, I felt Olympus’s stabilization helped deliver sharper images handheld, a valuable feature for beginners exploring close-up work or indoor photography.

Lens Ecosystem and Compatibility

Lens options can heavily influence your choice and long-term satisfaction. Nikon’s F-mount has a vast selection - 309 lenses compatible with the D3100, ranging from budget to professional grade, including excellent third-party options from Sigma, Tamron, and Tokina.

Olympus E-620 uses the Four Thirds mount lens system - with 45 lenses available. Four Thirds lenses tend to be smaller and more portable but less abundant compared to Nikon. This is before the Micro Four Thirds (MFT) standard took over Olympus camera lines.

If you want an affordable, wide lens ecosystem with plenty of glass for every genre - from ultra-wide landscapes to super-telephoto wildlife - Nikon is the clear leader.

Viewfinder and LCD Experience

When shooting through the optical viewfinder, clarity, accuracy, and coverage are critical for composition and focus confirmation.

Besides the magnification difference mentioned earlier, both offer 95% coverage, meaning the frame edges won’t be fully visible. Not ideal for perfect framing but typical of entry-level cameras.

The Nikon’s fixed 3-inch screen is easier to see in bright conditions, but Olympus’s fully articulated screen is a game changer for creative composition - think low-angle macros or self-portraits.

This flexibility makes Olympus ideal for vloggers or enthusiasts experimenting with live view, though the lack of touch interface feels like a missed opportunity.

Storage, Battery Life, and Connectivity

Nikon D3100 uses SD/SDHC/SDXC cards, a near-universal standard with fast write speeds and affordability. Olympus uses CF Type I/II and XD Picture Cards, which are bulkier and getting rarer in availability.

Battery life is slightly better on Nikon - rated around 550 shots per charge compared to Olympus’s 500. In practice, that extra 50 shots might mean the difference when on a daylong outdoor shoot without spares.

Connectivity is basic on Nikon with USB 2.0 and HDMI ports, plus optional Eye-Fi wireless compatibility for remote image transfer. Olympus stays minimal on connectivity, lacking HDMI and wireless.

Practical Shooting Examples: How Do Images Compare?

Here are sample images from both cameras in various genres:

Nikon D3100 screen back Olympus E 620 screen back

Notice Nikon’s superior dynamic range when capturing the shadow detail on the waterfall scene and smoother skin tones in portraits.

Olympus delivers pleasing colors but struggles more with noise in the night shot. The image stabilization shines in handheld macro shots, giving Olympus a slight edge in fine detail retention.

Summary of Strengths and Weaknesses

Olympus E-620’s sensor-based stabilization is its killer feature for handheld shooting, while Nikon’s overall image quality and autofocus speed give it a clear advantage for most types of photography.

Genre-Specific Recommendations

Let’s break down which camera would suit your photography pursuits best.

Portrait Photography

Winner: Nikon D3100
The D3100 produces better skin tones, smoother bokeh thanks to a larger sensor and access to high-quality Nikon primes. It also has eye detection autofocus aiding sharp portraits.

Landscape Photography

Winner: Nikon D3100
Superior dynamic range and resolution make Nikon better for capturing landscapes with fine detail and tonal gradations. Lack of weather sealing means carrying protection regardless.

Wildlife Photography

Winner: Nikon D3100
Faster AF, tracking abilities, and better burst mode makes Nikon preferable for wildlife, especially when paired with telephoto lenses.

Sports Photography

Winner: Nikon D3100
Better autofocus tracking and decent continuous shooting rate stand out in movement-intensive conditions.

Street Photography

Winner: Olympus E-620
Smaller, lighter body plus sensor stabilization and a flip-out screen make it a better fit for discreet shooting.

Macro Photography

Winner: Olympus E-620
Built-in image stabilization helps handheld macro work more than Nikon’s lack of sensor IS.

Night/Astro Photography

Winner: Nikon D3100
Better high ISO performance and dynamic range critical for night scenes.

Video Capabilities

Winner: Nikon D3100
Olympus lacks video entirely.

Travel Photography

Winner: Olympus E-620
Compact size, articulated screen, and in-body IS combine for travel convenience.

Professional Use

Winner: Nikon D3100
Larger lens lineup, better sensor, video support, and better battery translate to more versatility - even though true professionals may leap to higher-tier bodies.

Final Thoughts: Which Camera Should You Buy?

If you want a beginner DSLR that excels at image quality, autofocus speed, and offers video capabilities - with access to an enormous range of lenses - I wholeheartedly recommend the Nikon D3100.

However, if you prefer a lightweight body with sensor stabilization and an articulated screen for travel, macro, or street photography - and video isn’t important - the Olympus E-620 stands out as a unique offering despite its older Four Thirds sensor.

The price gap also matters: Nikon comes in notably more affordable for better specs; Olympus carries a premium with less robust performance but some nice usability perks.

If you want my personal advice: go Nikon D3100 for most use cases, but if portability and stabilization entice you for casual shooting and close-ups, the Olympus could still be an appealing choice.

I hope this breakdown helps you approach your camera purchase with clarity and confidence. Both are capable tools with distinct personalities - don’t choose blindly, but align the choice with your photography goals. Happy shooting!

Disclosure: All tests and evaluations here come from extensive hands-on sessions in real-world scenarios over months. Your mileage may vary based on lenses and shooting conditions.