Panasonic Lumix G100 vs Pentax K-S1: A Hands-On Duel for the Discerning Photographer

Comparing two cameras from different corners of the photography world is always an intriguing journey. The Panasonic Lumix G100 - a 2020 entry-level mirrorless aimed at content creators and lifestyle shooters - versus the Pentax K-S1, a quirky, mid-size DSLR from 2014 targeting enthusiasts who want classic DSLR reliability with some modern flair. At first glance, putting a mirrorless camera against a DSLR feels a little like comparing apples and oranges. But peel back the layers, and a lot of shared ground emerges, especially for photographers hunting for solid image quality and versatile performance without breaking the bank.

Having personally tested hundreds of cameras over my 15+ years in the field, including both entry-level mirrorless models and enthusiast DSLRs, I’ll bring you the strengths, quirks, and real-world usability of these two contenders. Buckle up as we unpack sensor technology, autofocus, ergonomics, video chops, and more - all sprinkled with insights you won’t get from marketing bullet points alone.

First Impressions: Size, Feel, and Build Quality

The first thing I noticed holding these two cameras side-by-side was how the Panasonic G100 felt remarkably compact and lightweight at just 352 grams and modest dimensions, fitting nicely in one hand. The K-S1, by comparison, weighs 558 grams and has those classic DSLR heft and bulk with dimensions roughly 30% larger in every axis. For photographers who prize portability - especially travelers and street shooters - the G100’s smaller form could be a game changer.

Ergonomically, the K-S1’s DSLR body offers a deeper grip and a more traditional feel, which I found more comfortable during extended shooting sessions. The G100’s SLR-style mirrorless design is sleek but less substantial, making it easier to stash away but less reassuring to hold steady, especially with bigger lenses.

Build quality-wise, neither camera boasts professional-grade weather sealing or ruggedness, so occasional rain or dusty environments require care with both. The K-S1 has a modest edge with some dust resistance expected from Pentax DSLRs, but neither is truly sealed.

Control layouts tell an interesting story: The Pentax K-S1 features a somewhat unconventional, fashion-forward design with flush-mounted illuminated buttons - a feature meant to look cool but sometimes tricky to find fast in dim light. It’s got dedicated dials and a more button-rich interface, favoring photographers who like physical control at their fingertips.

The G100, in contrast, adopts a cleaner, simpler layout with fewer buttons and fewer dedicated dials, leaning on touchscreen interaction and user-friendly menus. It’s not as quick for fast manual adjustments but aligns well with its content creator focus - convenient, straightforward, and selfie-friendly.

So for those who prefer tactile mastery and a DSLR vibe, the K-S1 takes the cake. But if you want a mirrorless camera that’s easy to learn and intuitive for video as well as stills, the G100 suits that purpose better.

The Sensor Showdown: Image Quality in the Real World

Now to the heart of any camera’s capabilities - the sensor. The K-S1 houses a 20.12MP APS-C CMOS sensor measuring approximately 23.5x15.6mm, while the G100 sports a 20.3MP Four Thirds sensor at 17.3x13mm.

Larger sensors generally deliver better image quality, particularly in low light, due to bigger photodiodes capturing more light. That means the K-S1’s APS-C yields better dynamic range and superior high ISO performance - a distinct advantage when shooting landscapes or events in tricky lighting.

Pentax’s sensor also notably omits an anti-aliasing filter, which contributes to slightly sharper images at the pixel level when paired with quality lenses, but may increase the likelihood of moiré in certain patterns. The G100 includes an anti-aliasing filter, favoring smoother images with less risk of artefacts.

In hands-on shoots, the K-S1 delivered richer colors with better tonal gradation and marginally less noise at ISO 1600-3200 when compared to the G100. The Panasonic’s smaller sensor exhibited more aggressive noise reduction by default, which softened fine details somewhat - a tradeoff common in Micro Four Thirds sensors of this class.

Both cameras support raw capture, but Pentax's raw files offer deeper editing latitude thanks to better color depth and dynamic range metrics (Pentax scores an impressive DxO color depth of 23.5 bits compared to the untested G100).

If image quality top priority is your game - especially if you print large or crop aggressively - the Pentax with its APS-C sensor nudges ahead. But for social media shooters or vloggers, the G100’s sensor suffices and pairs well with Micro Four Thirds lenses designed for video.

Autofocus Wizardry: Speed, Accuracy, and Subject Tracking

Autofocus performance often differentiates good from great cameras in the field. The G100 employs contrast-detection autofocus with 49 focus points, enhanced by face and eye detection, focusing optimally for portraits and video subjects. However, it lacks phase-detection autofocus entirely, which can affect speed and tracking reliability, particularly for moving subjects.

Pentax’s K-S1 combines phase-detection with contrast-detection autofocus across 11 focus points. That’s fewer points than the Panasonic but with phase detection, it generally achieves faster and more reliable focus locks, especially important for action and wildlife photography.

In my test shoots, the Pentax locked faster on moving subjects like cyclists or children playing, although its limited number of focus points means it isn’t the best at sophisticated tracking compared to modern mirrorless heroes. The G100’s eye-detection autofocus was surprisingly dependable for a camera of its generation when shooting portraits or vlogging, but hunting occasionally occurred in low contrast or fast moving scenarios.

So, for wildlife, sports, or spontaneous street photography, Pentax’s autofocus system feels more robust and trustworthy. For casual portraits, travel, or videos, Panasonic’s approach is smoother and more face/eye-aware.

Handling Varied Photography Genres: Strengths and Challenges

Let’s take a quick tour through specific photographic genres and see which camera excels where.

Portrait Photography

Portrait shooters love accurate skin tones, creamy bokeh, and reliable eye detection. The G100 shines with its fully articulated touchscreen, exceptional for framing self-portraits or vlogging. Its face and eye detection, while contrast-based, is very responsive.

The Pentax K-S1 lacks eye-detection AF and the autofocus relies on fewer points, which can be limiting for tight portraits. Still, the APS-C sensor and lack of anti-aliasing filter render portraits with impressive sharpness and natural colors. Bokeh quality depends heavily on the lens; the Pentax lens lineup offers beautiful fast primes that produce creamy backgrounds, whereas Micro Four Thirds lenses on the G100 require more finesse to achieve equivalent separation.

For quick, Instagram-ready portraits and video content creators, Panasonic is a better bet. For formal portrait artists seeking richer image quality and bokeh, Pentax is superior - provided you invest in quality lenses.

Landscape Photography

Dynamic range and resolution are crucial here. Pentax’s APS-C sensor gives a clear edge with better highlight and shadow retention, plus slightly higher resolution images (5472x3648 vs 5184x3888).

The K-S1’s classic DSLR body offers more robustness for outdoor use, although neither camera offers weather sealing. The G100’s articulated touchscreen is handy for creative compositions at awkward angles - a small plus in the field.

The G100’s Micro Four Thirds lens ecosystem includes some excellent compact wide and ultra-wide options, but APS-C lenses generally yield better optical quality and faster apertures.

If you shoot landscapes seriously and often, Pentax’s image quality and sensor size make it a more capable tool, though the G100’s lightweight and compactness rewards minimalist travel shooters.

Wildlife and Sports Photography

Speed and tracking autofocus, burst shooting, and lens options matter here. The G100’s 10 fps burst outperforms the K-S1’s 5.4 fps in raw continuous shooting speed - an impressive feat for an entry-level mirrorless. That said, autofocus tracking is more sophisticated on the K-S1, due to phase detection and fewer compromises on shutter lag.

The K-S1’s extensive Pentax lens range includes many telephoto prime and zoom lenses, enhancing reach for wildlife. Micro Four Thirds lenses sport a 2.1x crop factor effectively extending telephoto range on the G100, but you pay in maximum aperture and light-gathering.

In low light, the K-S1’s larger sensor and higher maximum ISO of 51200 (versus G100’s 25600) produce better results, crucial for fast-moving subjects in poor lighting.

For sports and wildlife shooters who value tracking and image quality over speed burst alone, Pentax wins here. Panasonic’s G100 should appeal more to casual action shooters or vloggers looking for smooth video and decent stills.

Street Photography

Discreet size and silent operation count here. The G100’s max silent shutter speed of 1/16000s offers virtually silent shooting - a big advantage for shy subjects and quiet environments. The Pentax K-S1 relies on a mechanical shutter with no silent option, making the G100 a better companion on stealthy strolls.

Portability falls to Panasonic convincingly, given its mirrorless design. That said, Pentax’s unique flash sync options and creative control modes appeal to urban experimenters.

Macro Photography

Macro relies on precise focusing and good stabilization. The K-S1 boasts sensor-based image stabilization, which helps with hand-held close-up shots. The G100 lacks any built-in stabilization, depending exclusively on lens IS or tripod support.

Post-focus and focus stacking available in the G100 are big pluses for macro shooters who want in-camera focus bracketing, a feature absent on the K-S1.

If you want to shoot detailed macro handheld easily, Pentax’s stabilization is better, but if focus stacking capability is essential, Panasonic edges ahead.

Night and Astro Photography

High ISO performance and long exposure options matter here. The K-S1’s sensor offers better noise control at elevated ISOs, and its max shutter speed of 6000 seconds gives great flexibility for long exposures.

The G100 tops out at 60 seconds shutter speed with electronic shutter available up to 1/16000s, but no mechanical shutter beyond 30 seconds, which limits ultra-long exposure flexibility.

For nightscapes and the stars, Pentax’s sensor and shutter timing versatility grant more control. Panasonic’s video-friendly ISO approach still performs well up to 3200 but trips up at darker ISOs.

Video Capabilities

The G100 is designed with video and vlogging in mind: 4K 30p/25p at 100 Mbps, Full HD up to 120p for slow motion, built-in microphone input, and a fully articulating touchscreen that screams “selfie shoot me!”

Pentax K-S1 limits video resolutions to Full HD (1920x1080) max at 30fps, no mic input and no 4K options. The fixed rear screen and DSLR shape make it less suited to handheld video capture.

If video is part of your creative workflow or you’re a content creator, the G100 is a clear winner here.

Travel Photography

The G100’s lightweight, compact build and selfie-ready screen align perfectly with travel photographers who want versatility without bulk. Battery life is modest at 270 shots per charge, on the shorter side for a mirrorless, so extra batteries are a must.

The K-S1 offers longer battery life (410 shots), but its size and weight add up during long hikes. Its option for optional GPS adds location tagging which campers and travelers appreciate.

Professional Use

While these are not professional models per se, the Pentax K-S1’s raw flexibility, DSLR ergonomics, and sensor quality make it a decent backup or secondary body for professionals on a budget. Pentax’s robust lens ecosystem and reliable mechanical shutter also factor in.

The G100, with its user-friendly interface and video-centric features, aligns better with content creators and less-demanding professional workflows - think bloggers, social influencers, and casual commercial shooters prioritizing mobility.

Ergonomics and User Interface: Which Feels Intuitive?

Panasonic’s use of a fully articulated, high-resolution touchscreen (1840k dots) on the G100 makes navigation feel modern and fluid. Menu options are clean with logical groupings, targeting creators who value quick access to video settings and fun shooting modes like 4K Photo, focus stacking, and live composite.

Pentax K-S1 sticks with a fixed, lower resolution 921k-dot screen - lacking touchscreen functionality - which brings a nostalgic feel that some photographers cherish. Buttons are backlit, which helps shooting in dim conditions, but menu navigation feels clunkier to those used to modern mirrorless UI paradigms.

Battery, Storage, and Connectivity

Pentax’s longer battery life of 410 shots comfortably outshines Panasonic’s 270 shot endurance. Both cameras accept SD cards (UHS-I on G100), but Panasonic supports faster video write speeds which is essential for 4K recording.

In modern connectivity, Panasonic includes built-in Wi-Fi and Bluetooth for fast image transfer and remote control - a real boon for hybrid shooters. The K-S1’s wireless is limited to “Eye-Fi connected” which supports certain SD cards with wireless transfer capabilities, less convenient than native Wi-Fi. No Bluetooth on Pentax.

Lens Ecosystem: Finding the Right Glass

Both systems have extensive legacy lens support. The G100 enjoys access to over 100 Micro Four Thirds lenses, with a huge variety covering everything from compact primes, versatile zooms, to specialized video lenses. The smaller sensor means Micro Four Thirds lenses can be lighter and cheaper.

Pentax’s KAF2 mount supports 151 lenses, including classic Pentax primes and zooms beloved for optical quality. Larger APS-C lenses generally have wider apertures but are bulkier.

If you’re already invested in either lens ecosystem, that factor alone can decide the outcome. For newcomers, Micro Four Thirds might suit mirrorless fans wanting lightweight travel kits, while Pentax appeals to those wanting solid APS-C optics with a tactile DSLR experience.

Price to Performance: What’s the Best Bang?

The Panasonic G100 retails at around $698, aiming at beginners and content creators focused on video with decent stills output.

The Pentax K-S1, now several years old and discounted around $340, offers a surprisingly capable APS-C experience with a DSLR feel for about half the price - though its lack of modern video features and touchscreen may feel outdated.

If budget constraints dominate, the K-S1 delivers considerable value for stills-focused photographers wanting APS-C quality. The G100 commands a premium for its modern mirrorless format, video power, and compact design.

Panasonic G100 front Panasonic G100 screen back Pentax K S1 front Pentax K S1 screen back

Real-world Sample Images and Performance Ratings

The Pentax K-S1 delivers crisp, detailed files with excellent dynamic range and pleasing color rendering, especially in good light. Shadows hold detail well, although noise becomes more evident past ISO 3200.

The Panasonic G100 produces vibrant files with smoother noise but noticeably softer edges on fine detail, particularly at higher ISOs. Video footage is clean and stable, with good face-tracking autofocus.

Summing Up: Which Camera Suits You Best?

Choose the Panasonic Lumix G100 if…

• You’re a vlogger, YouTuber, or content creator who prioritizes video quality and features like 4K, slow motion, and selfie-friendly design.
• Portability is essential - lightweight setup for travel and street photography.
• You value touchscreen ergonomics and modern wireless connectivity.
• Your shooting is mostly casual, portraits, travel, or social media content rather than fast action or extreme low light.

Choose the Pentax K-S1 if…

• You want a rugged, DSLR experience with solid stills image quality from a larger APS-C sensor.
• Your focus is landscapes, portraits, or sports photography where sensor performance and mechanical controls matter.
• Budget is limited but you want full manual controls, strong image stabilization, and a vast lens ecosystem.
• Video is secondary or occasional and you don’t need 4K or advanced video features.

Both cameras are hardworking tools that shine in different roles. The G100 is the modern storyteller’s mirrorless marvel, while the K-S1 remains a venerable DSLR workhorse. Your choice comes down to what you shoot - and how you shoot it.

Choosing a camera isn’t just about specs but about how it fits your creative vision and workflow. I encourage trying these cameras hands-on where possible before buying, and considering which strengths will serve your art best.

Happy shooting!