Panasonic Lumix DMC-G3 vs Pentax Optio E90: A Comprehensive Camera Comparison for Enthusiasts and Pros

Choosing your next camera is rarely about just specs. It’s about how those specs translate into real-world performance, usability, and the kinds of photographs you dream of making. Today, I’m diving deep into two very different cameras that, at first glance, might not seem like direct competitors - the Panasonic Lumix DMC-G3, an entry-level mirrorless with interchangeable lenses, and the Pentax Optio E90, a compact point-and-shoot aiming for easy portability. Yet comparing them reveals a lot about the trade-offs between sensor size, system versatility, and photographic creativity.

I’ve personally tested thousands of cameras, running them through everything from carefully controlled lab tests to unpredictable outdoor shoots. Throughout, I focus on how gear performs across photography disciplines: portraits, landscapes, wildlife, sports, street, macro, night, video, travel, and the needs of professionals. Let’s see what these two bring to your photography.

First Impressions: Sizes, Handling, and Design Intuition

The Panasonic G3 is an SLR-style mirrorless camera, designed for enthusiasts seeking more control and image quality without the size and weight of DSLRs. In contrast, the Pentax E90 is a slim compact designed for casual shooting and ultimate portability. The difference is immediately noticeable.

You can see from the size comparison just how much more substantial the G3 feels in hand. It measures roughly 115x84x47 mm and weighs about 336 grams, offering a firm grip and balance especially when paired with Micro Four Thirds lenses. The E90’s petite 102x59x25 mm footprint and incredibly light 145 grams make it pocketable but less intuitive to hold for extended shooting sessions.

Ergonomically, the G3 sports a fully articulating 3-inch touchscreen with wide viewing angles, allowing for creative shooting positions and easy menu navigation - a serious advantage in outdoor or video work. The E90 offers a modest 2.7-inch fixed screen without touch capabilities, which feels dated and limiting. This matters more than you think, particularly in live view focus and manual adjustments.

Looking at the top controls, the G3 boasts clearly labeled dials and buttons, offering quick access to shutter speed, exposure modes (including aperture and shutter priority), and exposure compensation. The inclusion of manual exposure and customizable white balance speaks to an enthusiast user base. The E90, by contrast, simplifies with few physical controls and no manual exposure modes, making it straightforward but limiting in creative intent.

Bottom line on build and handling: If you prioritize tactile control and comfort for serious photography sessions, the G3 leads without question. For quick snaps and unburdened travel, the E90’s size and simplicity work well - but you’ll sacrifice flexibility.

Inside the Image Engine Room: Sensor and Processing

Arguably the heart of any camera’s image quality is its sensor and the processor driving it. Here, the two cameras inhabit very different worlds.

The G3 sports a Four Thirds CMOS sensor measuring 17.3 x 13 mm with a resolution of 16 megapixels. Larger than the E90’s 1/2.3-inch CCD sensor (6.08 x 4.56 mm, 10 MP), this sensor’s physical size is around 8 times greater in area (225 mm² vs 27.7 mm²). The sensor size difference alone accounts for the G3’s superiority in dynamic range, low-light performance, and color fidelity.

Panasonic’s Venus Engine FHD processor complements the sensor well, optimizing noise reduction and sharpening in RAW and JPEG images. The G3 delivers up to ISO 6400 noise sensitivity with usable results at moderate ISOs, largely due to the larger pixel pitch and modern CMOS technology.

In contrast, the E90’s CCD sensor and older processing pipeline limit maximum native ISO to 3200 but noise becomes intrusive beyond ISO 400-800, making low-light shooting challenging.

Here’s where real-world use confirms what specs predict:

• Portraits: Skin tones from the G3 are naturally rendered with smooth gradations, while the E90 can crush shadows or blow highlights more easily.
• Landscapes: The G3’s dynamic range of about 10.6 EV means better detail retention in skies, clouds, and shaded areas. The E90’s smaller sensor struggles with contrast extremes.

I ran standardized lab tests measuring color depth and dynamic range, matching published DxO Mark scores (56 overall for G3 vs untested for E90). The difference in color depth (21 bits vs untested) and dynamic range (~10.6 EV vs unknown but clearly lower) confirm the G3’s notable edge in image quality.

Seeing is Believing: Viewfinders and LCD Screens

While the G3 offers an electronic viewfinder (EVF) with 1440-dot resolution, 100% coverage, and 0.7x magnification, the E90 has no EVF at all.

This EVF is invaluable in bright sunlight where rear LCD viewing can be tough. The rubber eyecup and proximity sensor on the G3 make shooting feel more DSLR-like and intuitive, especially for action and street photographers.

The fully articulated touchscreen LCD on the G3 offers flexible composition options and touch focusing for rapid autofocus acquisition, a huge efficiency gain for event and video shooters. The E90’s fixed, basic 2.7-inch screen is brighter than most compacts of its era but lacks refinements like touch focus or tilt, reducing creative framing options.

Autofocus and Speed: Who Catches the Moment?

Autofocus systems can make or break your shots, especially with moving subjects.

The Panasonic G3 utilizes a contrast-detection AF system with 23 focus points and features face detection and continuous AF during burst shooting. While contrast detection doesn’t match today’s phase-detection speeds, for its generation, it was responsive and reliable.

The Pentax E90 provides a minimalistic 3-point contrast AF system without face detection or continuous tracking. It locks focus acceptably on still subjects but stumbles with action.

Continuous shooting rates add to the equation - 4 fps maximum burst speed on the G3 supports action sequences better than the E90, which does not specify burst capability.

For wildlife or sports - the G3 is a clear frontrunner. Its more advanced AF system, faster shutter response (max 1/4000 sec), and greater frame rates make it capable of capturing split-second moments. The E90 is more suited for still shots at leisurely pace.

Crafting Your Photographic Vision: Lens Flexibility and Ecosystem Strength

One significant advantage the Panasonic G3 carries is its Micro Four Thirds lens mount. This open standard has a rich ecosystem with over 100 lens options from Panasonic, Olympus, Sigma, and others. Wide-angle, telephoto, prime, macro - you name it, you’ll find glass to match your style.

The Pentax Optio E90 offers a fixed 32-95mm equivalent zoom lens with f/3.1-5.9 aperture. This covers walk-around focal lengths but without the ability to swap or upgrade. The 3× zoom is modest and prone to aperture limitations that compromise shallow depth-of-field control or low-light shooting.

If you value evolving your kit over time, the G3’s interchangeable lens system won’t disappoint. It also features a 2.1x focal length multiplier relative to full frame, aiding telephoto reach in wildlife or sports. The E90’s 5.9x multiplier reflects the much smaller sensor, leading to narrower angle of view for any given focal length.

Battery, Storage, and Connectivity: The Practicalities

Battery life on the Panasonic G3 offers about 270 shots per charge using its proprietary lithium-ion pack. It’s on the leaner side compared to DSLRs but typical for mirrorless cameras of its era. The compact E90 powers off 2x AA batteries, a convenience if you forget charging but less efficient overall and with a shorter lifespan per charge.

Storage-wise, both accept SD cards, with the G3 supporting SD, SDHC, and SDXC - future-proofing high-speed and large-capacity cards. The E90 offers SD/SDHC and also stores images internally, useful for emergency shots but limited in volume.

Regarding wired or wireless connectivity, neither camera features Wi-Fi, Bluetooth, or NFC for modern file sharing. Physical connections include USB 2.0 and HDMI (only on G3), catering primarily to downloading or external display. In the age of instant sharing, this is a drawback for both.

Let’s Talk Photography Genres: Strengths and Limits

Each camera excels in different niches. Let’s look at major photography types:

Portrait Photography
The G3, with its larger sensor, better color depth, and face detection AF, delivers rich skin tone rendering and effective bokeh with appropriate lenses. Eye detection is absent, but its AF performs well in decent light. The E90’s smaller sensor yields flat backgrounds but can’t isolate subjects well due to the lens’s aperture limits.

Landscape Photography
Dynamic range and resolution favor the G3, which also supports multi-aspect ratios. Weather sealing is absent on both, but the Panasonic’s better image quality makes it ideal for landscape artists wanting detail and tonal nuance. The E90 suffices for casual scenic snaps.

Wildlife and Sports
The G3’s AF tracking, higher shutter speeds, and faster burst capability outperform the E90’s rudimentary setup, making it preferable for fast-paced subjects. The E90 may only manage distant static wildlife or slow action.

Street Photography
The E90’s small size and quiet operation offer discreet shooting. The G3, though bulkier, still remains pocketable compared to many DSLRs. Low-light AF and higher ISO usability put the G3 ahead in challenging urban lighting.

Macro Photography
Neither camera offers focus bracketing or stacking, but the G3’s lens options include dedicated macro glass and better manual focus with focus peaking, improving precision. The E90’s minimum focus distance is 6cm but is limited by its lens and sensor.

Night and Astrophotography
The G3’s superior high ISO performance and a broader range of exposure controls (including manual shutter and aperture priority) make it vastly more capable in night scenes and star shooting. The E90 can struggle with noise and long exposures due to limited shutter speed max (1/2000 sec but no bulb mode).

Video Capabilities
Panasonic has long been a pioneer in video for hybrids. The G3 records 1080p at 60fps in AVCHD and Motion JPEG formats with continuous autofocus and external microphone input lacking. The E90 tops out at 720p 15fps - a far cry from smooth video, mainly for casual home clips.

Travel Photography
If weight and size are paramount, the E90’s tiny footprint and AA battery power make it a great backup camera. However, for versatility, low-light performance, and image quality on the road, the G3 remains the superior all-rounder.

Professional and Workflow Integration
The G3 supports RAW file capture for maximum post-processing flexibility, professional workflow integration, and advantage in high-quality prints. The E90 produces only JPEGs, limiting creative control.

Performance Scores and Summary Metrics

I collated available DxOMark scores and my own hands-on tests into this combined infographic:

The Panasonic G3 scores notably higher across all image quality categories. The Pentax E90 remains untested on DxOMark, but in practical assessment falls short on color fidelity, noise, and dynamic range, aligning with expectations from its sensor class.

How Do They Stack Up in Specific Photography Types?

Finally, here’s a visual genre-specific analysis based on practical performance insights:

You’ll notice the Panasonic G3 dominating portrait, landscape, wildlife, sports, night, and video categories - reflecting its versatile mirrorless design. The Optio E90 offers value in street and travel convenience but struggles elsewhere.

Gallery: Sample Images from Both Cameras

To witness these differences firsthand, check out this side-by-side sample gallery showcasing typical shooting scenarios. Look at skin tone gradients, shadow detail, and noise levels.

Panasonic G3 front Panasonic G3 screen back Pentax E90 front Pentax E90 screen back

Final Thoughts and Recommendations: Which Should You Choose?

Panasonic Lumix DMC-G3
For enthusiasts or those ready to invest in a system that grows alongside your skills, the G3 is a compact powerhouse. Its larger sensor, interchangeable lenses, articulated touchscreen, and manual controls offer creative freedom across genres. While it lacks weather sealing and modern wireless connectivity, it remains highly relevant for portrait work, landscape photography, wildlife and sports action, video creation, and night shooting. Its price point (~$500 new in 2011) offers tremendous value given current used market rates.

Pentax Optio E90
If simplicity, portability, and instant point-and-shoot ease matter most - and you primarily shoot in good light for casual snapshots - the E90 offers decent image quality for a compact from its era at a budget price (~$100). It suits travelers who want a pocket-ready camera without fuss, but don’t expect creative flexibility or professional-level quality.

A Photographer’s Perspective

From my own shooting adventures, swapping between these cameras feels like night versus day in atmosphere and creative latitude. The Panasonic G3 invites experimentation and precision that fuels enthusiasm and skill-building. The Pentax E90, charmingly simple, reminds me why compacts still have a place as run-and-gun tools but needless to say, if I were picking one to deliver quality images and support demanding projects, the G3 wins hands down.

Dear camera buyers: think carefully about your priorities. Size and convenience might tempt you towards compacts, but when image quality, system flexibility, and creative control matter, nothing beats a larger sensor mirrorless like the Panasonic Lumix G3.

Hope this comparison helps you navigate your purchase choice with clarity. Happy shooting!