Canon PowerShot G7 X Review and Test

Dec 17, 2014--The PowerShot G7 X is Canon's newest compact camera with a 20MP BSI CMOS sensor and an aspect ratio of 3:2. It incorporates Canon's newest image processor--DIGIC 6—that provides fast image recording and high-speed continuous mode. This is the same processor found in the company’s 7D Mark II, albeit in a dual version in the DSLR.

The Canon PowerShot G7 X is a compact camera with a high-speed zoom lens. The unit contains a large 20MP CMOS sensor and a DIGIC 6 processor. A multifunctional lens ring and additional setup dials make handling easy.

The camera has an integral high-speed 4.1X 24-100mm zoom lens (35mm film equivalent). The variable aperture still retains a high-speed character with the change from wide to tele, being just f/1.8 to f/2.8, which is quite unusual for compact cameras. In combination with the large sensor (for a compact camera) it allows users to easily create images with a shallow depth of field.

The camera has a pop-up flash, but an accessory shoe for external flash is missing. The camera offers Wi-Fi and NFC functions. The interfaces are located on the right hand side of the body.

By pressing the “RING FUNC.” button on the back the photographer can set up the function of the lens ring. In standard automatic mode (STD) this ring is used to change ISO speed settings, but of course it can also be used for zooming, manual focusing, white balance settings and more. The ring is located flush with the body and is very slim. A larger ring would be more comfortable.

The Canon G7 X has a mode dial on the top that allows the photographer to choose standard exposure modes and automatic modes. A second dial is used for EV compensation control. A zoom switch helps to change focal length, but the photographer can use the lens ring to zoom as well.

The camera has a 3-inch LCD screen (1,040,000 RGB dots) that is used as control center for menu setup but also as an electronic viewfinder. A dedicated EVF or optical viewfinder is missing. The LCD screen can be flipped upwards (180 degrees) to shoot selfies. In full automatic mode, the camera will switch to the portrait scene mode and changes the lens ring function to focal length. The tilting monitor is handy when taking macro shots near the ground, but a fully articulated LCD with a swivel joint would be more helpful.

The new Canon offers all standard exposure modes: P, TV, AV and M. It has a setup dial on the top which offers an additional “C” mode to save a customer defined setting In addition, the G7 X offers scene modes and a video mode that allows the use of manual exposure settings when recording videos. A second dial, which is located directly beneath the mode dial, allows for EV compensation settings in a  +/- 3 EV range.

The monitor can be flipped upwards by 180 degrees. This can be used for photographing images near the ground or more likely is aimed at the selfie crowd.

The control field on the back allows the user to set up drive mode, flash mode, focusing mode and display settings. It offers a setup dial that encircles the control field and is helpful for menu navigation or image parameter control. The camera has a built-in flash that is activated by a little switch on the left hand side of the body. An accessory shoe is missing, so the G7 X can't use external, add-on flash systems.

Comments on Image Quality

Color: The Canon reproduced the GretagMacbeth chart with a little over-saturation, with red colors especially boosted. This is noticeable in our portrait shot and the test box shot, where red elements seem to “glow.” The skin tone reproduction is good, but the skin tone in our portrait has a visible shift into the magenta area of the color space, which is used, we believe, to optimize or beautify these color areas. In some pictures this effect looks a bit overdone.

The automatic white balance system showed a very good performance. The gray patterns in the test chart are nearly perfectly centered and only the brightest gray and nearly white pattern show shifts into the yellow and green direction. The background in our portrait shot was reproduced with a slightly bluish cast.

The camera reproduced the portrait scene with very high, even exaggerated sharpness (see details in hair structure). The saturation of the red color (t-shirt) is very high and the skin tones have a slightly high magenta rate.

 Sharpness: The camera showed a very good result in the resolution test. The test chart was reproduced with 3350 of 3648 lines per picture height. The high sharpness is also a result of a very intense sharpness filtering and image processing by the DIGIC 6 processor and causes noticeable overshot and undershot effects. These effects are noticeable in our portrait shot: The hair structure of the model is over-sharpened and has a slight artificial look. In the test box shot the over sharpening of the contrast lines of the large Siemens star causes a strange result: The contrast line has a halo effect that is blurred (elements outside of the plane of focus), so the white halo extends into the black area of the lines.

The test box shot was reproduced with very neutral gray tones in the background. Colors look natural, even though some nuances (red colors) have a very high saturation.

Noise: The noise test results of the Canon G7 X are very good. The camera showed a slightly higher noise level than Canon cameras with an APS-C sized sensor, but this is still a very good result for a compact camera. The luminance noise factor doesn’t cross the 1.0 percent line until ISO 3200. Color noise gets visible in images with ISO 1600 settings and higher: color noise is filtered by an efficient algorithm. Only at ISO 12,800 do the noise filtering effects become annoying.

The camera showed excellent results in the dynamic range tests. The Stouffer chart was reproduced with 11.2 f-stops, which is a remarkably high result for a compact camera. Between ISO 200 and ISO 3200 the camera keeps this high level with 10 to 11 f-stops.

Comments on Video Quality

Due to its good color reproduction with only slightly oversaturated nuances, the camera achieved a high image quality result. The white balance settings are good and the camera neutral and is able to record neutral and coherent colors.

The resolution results are a little disappointing: The camera reproduced the full HD test chart with 684 of 1080 lines per picture height. Because of the low sharpness there are only minor aliasing or Moiré effects.

The results of the noise tests are very good: The camera records nearly noise-free videos up to ISO 1600. At ISO 3200 color noise artifacts become noticeable; at ISO 6400 the noise is clearly visible. Dynamic range results are extremely good and comparable to the results in photo mode. The camera achieved a maximum of 11.7 f-stops, which is a very high result for video recording system.

Pro

compact camera with large image sensor

manual camera settings; Raw mode

shallow depth of field effects possible (due to high speed lens and large sensor)

Con

missing optical viewfinder

These are edited test results and comments by Betterphoto, the testing lab for TIPA (Technical Image Press Association), an organization in which I serve on the Technical Committee.

Samsung NX1 Test and Review

Dec 10, 2014--The newest Samsung CSC (compact system camera) is the NX1. The camera has a 28MP (megapixel) APS-C sized images sensor and a hybrid AF system with 205 AF sensors (phase detection: 153 cross type sensors) and 209 AF areas (contrast metering). This makes focusing with the NX1 very fast and reliable, especially when using very fast burst modes for sports photography and similar photographic situations. The camera claims a burst mode with up to 15 frames per second, which we achieved during our tests.

The Samsung NX1 is an APS-C compact system camera with very high resolution. It has a 28MP sensor, a 2.36MP electronic viewfinder and a fast AF system. It has a massive metal body and is sealed/protected against humidity and dust. It is able to record videos in full HD and 4K.

In contrast to former NX systems with electronic viewfinders (EVF), which showed a blank or frozen image when shooting in burst mode thus making it near impossible to follow a fast moving object, the new viewfinder of the NX1 is perfectly adept at this function and allows for uninterrupted viewing. Adding to this functionality is the fact that the high resolution EVF has 2.36 million RGB dots. An eye sensor near the ocular automatically toggles between EVF and LCD image or the user can activate an “EVF” switch to change monitor mode manually.

The camera has a built-in pop-up flash system. In addition it offers an accessory shoe for external flash systems or remote trigger systems for studio flash systems. All interfaces are located on the left hand side of the body. The camera offers USB 3.0, HDMI, a microphone jack and an earphone jack.

In manual focusing mode, the camera automatically activates the magnifier function and focus peaking when the photographer moves the focus ring on the lens system. The lens ring can be used for additional settings because the camera supports Samsung's “iFunction” technologies, which allows the user to change image or exposure parameters with the lens ring.

The camera uses a combination of control field and a setup dial for menu navigation. The “Mobile” button near the top indicates the Wi-Fi function of the camera. A smartphone or tablet computer can be used as remote control.

The camera offers four function buttons on the left hand side of the top to set up AF mode, exposure metering, ISO speed and white balance directly. The status LCD on the right can be illuminated.

The camera has three setup dials to change image parameters and for menu navigation. The first dial is located near the shutter release button and on/off switch. The second wheel on the back (near the top) and the third dial is a combination of cursor control field and setup dial. The camera has less function buttons than professional Canon or Nikon cameras, but nevertheless handling is comfortable. The mode dial on the top can be used for user-defined setups (C1, C2). The dial on the left hand side sets up image shooting modes (single shot, burst mode high, burst mode low, self-timer). Also on the left are function buttons for ISO speed, white balance, AF mode and exposure metering mode.

The 3-inch LCD (1,036,000 RGB dots) can be moved upwards by 90 degrees and downwards by 45 degrees. It is helpful, but a fully articulated screen would be better.

Comments on Image Quality:

Color: The NX1 showed excellent results in our color tests. The test chart was reproduced with a little over-saturation, but still on a very good level. Some blue nuances are exaggerated, while the red colors are reproduced very precisely. The mean color error level is very low.

The Samsung NX1 reproduced the test box very clearly and crisply. The colors look natural and the differentiation even of difficult red nuances is very good.

Brighter skin tones have a slightly higher magenta rate. The automatic white balance system did a really good job. In darker color areas, it tends towards cooler nuances and the brighter tones are reproduced with a little yellowish or greenish character.

Sharpness: The camera showed an excellence performance in sharpness and resolution tests. The ISO 12233 test chart was reproduced with 4108 lines per picture height (nominal sensor resolution 4320 lines). It achieves this remarkably high result without any exaggerated sharpness filtering and the over- and undershot results are very low. This helps reproduce fine details like the hair of our model or the metal structures in our standard test box very clearly, with clean and natural results. The high sharpness and crisp look is also a result of the very good color differentiation.

Noise: The Samsung NX1 showed very good results in our noise tests. Even though the camera uses a sensor with extremely high pixel density, the luminance noise results are on the same level as the results of cameras with 20 or 24MP APS-C sensors. Up to ISO 12.800, the luminance noise level is lower than 1.0 percent, which is very good. Color noise is nearly invisible up to ISO 1600. Between ISO 1600 and ISO 6400 it becomes visible, but anti-noise filtering effects are very decent. At higher ISO settings these filtering artifacts get annoying, but are acceptable up to ISO 12,800. The highest ISO modes show a very intense filtering with visible loss of image details.

The dynamic range results are good, but a little lower than the results of some other APS-C cameras. The NX1 achieved a maximum of 11 f-stops and keeps a high 10-11 f-stop level up to ISO 1600; at higher ISO speeds, dynamic range will drop to 7.51  f-stops (ISO 51,200).

The portrait shot shows very nice skin tones. The exposure settings are perfect (P mode, ISO 100) and the differentiation in the red colored t-shirt is excellent.

Comments on Video Quality

The camera showed an excellence performance in full HD mode: The ISO 12233 chart was reproduced with 905 of 1080 lines per picture height. Videos in full HD mode look very crisp--sometimes even a little over-sharpened. Due to this high sharpness you may notice some moiré effects in this mode.

The results in 4K mode are a little disappointing. The camera reproduced the test chart with 1228 of 2160 lines. Videos in 4K mode have a little softer look than in full HD mode. The color reproduction in video mode is very good. Just like in photo mode, all colors have a very natural look and show nearly perfect color differentiation.

The noise results are very good. The camera allows the user to set ISO speed in manual mode but is restricted to ISO 6400 when recording videos. Dynamic range of videos is on a very high level (about 10 f-stops between ISO 100 and ISO 1600).

Scorecard

Pro

very fast camera system; very fast AF system

high resolution sensor, high resolution images

high resolution EVF

very good color reproduction

Wi-Fi and Bluetooth

tilting LCD

4k video

Con

dynamic range results should be a little higher

monitor cannot be turned sideways (can only flip up- and downwards)

The lab test and comments about the Samsung NX1 were done by Betternet, the Technical Image Press Association’s (TIPA) affiliated testing lab. I am a member of the association’s Technical Committee and have edited the report for this posting.

Olympus E-PL7 Review and Tests

Olympus E-PL7 Test and Review

The following review and test of the Olympus E-PL7 was done by the TIPA affiliated testing lab, Betternet. I serve on the Technical Committee of TIPA and have edited the test results for this posting. Visit www.tipa.com for more on the organization.

The Olympus E-PL7 is the newest camera in the PEN series. Like all PEN cameras, it lacks an integral viewfinder, but offers a large LCD screen on the back, a 3-inch screen with a resolution of 1.037.000 RGB dots. It has a sophisticated swivel mechanism that can be used to turn the monitor up- and downwards. It can also be tilted to the front when using the camera for “selfies.”

The E-PL7 is the newest model in Olympus PEN series. The camera offers a 16MP sensor, a swivel LCD for better image and menu control, a Wi-Fi module and a very easy handling.

The camera has a standard accessory shoe for add-on flash systems. Olympus supplies the E-PL7 with a small, compact flash, but in addition the camera can use standard flash systems or remote triggers for studio systems. The E-PL7 has an additional electronic interface on its back, right below the accessory shoe. This is where optional electronic viewfinders or external microphones can be mounted.

The Olympus E-PL7 is very small. Although not as small as the Panasonic GM series, it is nevertheless a very compact system.

The camera offers all standard exposure modes such as P, S, A and M, but is really designed for easy handling with numerous Scene modes. There are 25 image modes including such standard modes as portrait shot or “enhanced portrait.” There are very specific  modes like “candlelight,” “high key” or “documents,” the last being for images of printed pages that can be used with OCR (Optical Character Recognition) software.

The camera has a large mode dial on the top. In addition to standard modes it offers Scene mode settings with 25 programs and an ART mode for special filter effects. The dial, which encircles the shutter release button, is used to set up image parameters.

The camera is equipped with an integrated image stabilizer. Based on sensor shift technology, it can be used with every lens attached to the camera. The camera uses a 3-axis system and during tests we gained a 3EV advantage.

The camera has a swivel monitor that can be used for selfies. Of course, it is also helpful for all other scenes or when recording videos.

 The camera has a very robust and stylish body built on a metal chassis. Compared to other PEN cameras, the handle on the right hand side of the body is a bit thicker, which makes shooting and working with the E-PL7 more comfortable. The setup dial encircles the shutter release button and can be reached very easily. In combination with the 4 way control field on the back it is easy and comfortable to set up all parameters. Additional function buttons on the back or on the slanted top edge of the camera also help to set up the camera quickly and easily. The camera is equipped with a Wi-Fi module for connection to a smartphone or tablet.

The camera offers a 3-inch monitor with 1,037,000 RGB dots. The interface for an optional EVF, which can be mounted on the accessory shoe, is covered by a cap.

E-PL7 Image Quality Tests

Color: The E-PL7 created slightly under-saturated images, like nearly all Olympus PEN models. The error level is very low. Compared to many other camera systems (Nikon, Pentax), the dark blue nuances are reproduced very naturally. The white balance system causes a slightly bluish character and only the brightest gray patterns in our test chart show a shift into the yellow/green direction. Skin tones match nearly perfectly to their given values.

The standard test box shot shows natural colors and a good resolution result. Differentiation of red and green colors is very good, the colors of the Kodak test pattern are reproduced correctly.

Sharpness: The camera showed a good performance in our resolution and sharpness tests. The test chart was reproduced with 2848 of 3456 lines in picture height, which is an average result for a compact system camera. The camera could have gained a higher result if the image processor would use a little higher sharpness filtering and contrast line enhancement. Compared to other cameras the over- and undershot effects are very low. The graph of the edge profile shows a slight and very soft buckle/bulging form. Chromatic aberration effects also reduce the resolution result, but are on a good/acceptable level. All tests were done with the provided camera lens, the M.ZUIKO DIGITAL ED 14-42mm 1:3.5-5.6 EZ Pancake.

The Olympus E-PL7 showed a good performance in our portrait shot. The exposure resuts (P mode, lowest possible ISO mode “200”) are perfect. Skin tones are reproduced very naturally.

Noise: The Olympus showed an excellence performance in our noise tests. The luminance noise factor is extremely low. Between ISO 200 and ISO 1600 it is nearly 0.3 percent. The color noise artifacts get visible in images taken with ISO 1600 and higher. They get really annoying at ISO 25,600. Limiting your ISO to 6400 or 12800 would be the best bet.

The white balance system causes a slightly bluish character and only the brightest gray patterns in our test chart show a shift into the yellow/green direction.

The dynamic range results are very good: The camera gained a maximum of 10.9 f-stops and keeps a high level of about 10 f-stops up to ISO 3200 mode.

E-PL7 Video Quality Tests

The Olympus showed only average results in the video tests. The test chart was reproduced with 714.3 lines of 1080 lines in picture height, which is acceptable, but a little less than the top results created by Panasonic cameras with comparable sensor technology.

The color reproduction is similar to the color reproduction in photo mode: Colors have a very natural look, the white balance system hits the correct colors (only bright colors have a slightly yellow shift). Dynamic range is also comparable to the photo results. The camera gathered a maximum of 10.7 f-stops and about 9-10 f-stops in higher ISO modes. This is a very good result for a video camera.

Pro

compact body; stylish retro design

very good color reproduction

Con

missing optical view finder

missing integrated flash system (small external flash system is provided with the camera)

only 3 axis image stabilizer (Olympus offers cameras with 5 axis stabilizer)