Panasonic ZS70 Review

The Panasonic ZS70 (Panasonic TZ90 in most of Europe) accommodates an optical 30x zoom of the equivalent of 24 to 720 millimeters in a housing that is just over four centimeters flat. [Photo: Panasonic]

 

As the successor to the ZS60 (TZ80 – TZ81), the Panasonic ZS70 (Panasonic TZ90 in most of Europe) offers a 1/2.3″ sensor with a resolution of only 20 megapixels, which works with back-exposed CMOS technology. [Photo: Panasonic]

 

In addition to a 1.2 million pixel viewfinder, the Panasonic ZS70 (Panasonic TZ90 in most of Europe) also features a 7.5-centimeter touchscreen with a million-pixel resolution, which can be raised by up to 180 degrees.

 

In addition to the classic creative programs P, A, S, and M for semi-automatic or manual exposure control, the photographer also has numerous scene modes as well as the intelligent automatic mode at his disposal for shooting.

In addition to faces, scene movements, and camera shake, this mode also recognizes the objective itself in order to optimally adjust the camera or exposure parameters to it. In addition, the photographer has numerous filter and retouching functions at his disposal, for example, to embellish portraits.

Despite the compact housing, an electronic viewfinder with a resolution of 1.2 million pixels is integrated. Thanks to the proximity sensor, it activates automatically as soon as the camera is held up to the eye. Alternatively, the 7.5-centimeter display can be used for image composition.

A new feature is the ability to fold the screen up by up to 180 degrees, which not only simplifies ground-level photography, but also the so-called selfies. Thanks to the touch screen, it is also possible to focus on a scene detail with a fingertip on the display, and the Panasonic ZS70 also offers a touch trigger function on request.

The continuous shooting function achieves a fast ten frames per second at full 20-megapixel resolution. In addition, the Panasonic ZS70 (Panasonic TZ90 in most of Europe) also offers the 4K photo functions familiar from other Lumix models.

Thanks to the 30 frames per second at a resolution of eight megapixels, the right moment is not missed with action-packed scenes. In addition, the Panasonic ZS70 can move through the focus area in this mode so that you can select the desired focus point afterwards. It is also possible to combine all focus points in one image thanks to focus stacking.

 

The tripod thread of the Panasonic ZS70 (Panasonic TZ90 in most of Europe) is slightly outside the optical axis.

 

On the back of the camera is the 7.5 cm (3″) LCD touch screen that folds 180 degrees upwards for selfies. Two small magnets on the foldable LCD ensure that the display cannot move easily in the folded position.

In addition to the display, the photographer also has a small electronic viewfinder with eye sensor and diopter compensation at his disposal.

Unfortunately, the roller for adjusting the diopter compensation is located towards the inside of the camera, which forces the photographer to remove the camera from the eye when adjusting the compensation, if the left eye is to use the viewfinder.

If the right eye is intended for the viewfinder, then one does not necessarily have to put the camera down again and again, but one still has to fumble around with the finger close to the eye or eyelid in order to adjust the diopter compensation.

Also on the back of the camera are the various operating elements, such as the four configurable function keys and a rotary knob with internal speed selection keys for focus, flash, scroll, and exposure correction functions.

On the top of the camera are the mode dial, zoom lever, shutter release button, video recording button, and on/off switch. There is also a rotating ring around the lens on the front. Depending on the operating mode, the time or aperture, as well as the (manual) focus, can be conveniently set.

Of course, the touch screen on the back of the camera allows a variety of functions to be selected. The touch autofocus is particularly interesting. This allows the photographer to touch a point on the display, the camera then sets the focus on this point. This function is also available in combination with the viewfinder. While the photographer is looking through the viewfinder, he can move the focus point on the display with his finger.

The shutter release is very fast, especially in wide-angle with less than 0.2 seconds, but is significantly slower in telephoto with up to just over 0.4 seconds.

You look in vain for a flash shoe, and the built-in flash sits unfavorably between the “Lumix” logo and the small handle. This positioning makes it easy to accidentally have your finger in front of the flash, which naturally leads to unattractive illuminated areas when shooting.

The flash illumination in the laboratory did not surprisingly show a good illumination in the middle of the image and then a decrease in illumination towards the corners of the image. From a radial distance of approx. 73 %, the flash illumination becomes visibly lower.

SDHC or SDXC memory cards are used for recording. These are inserted into the memory card compartment on the underside of the camera, which can be seen after the simply secured flap has been opened.

The memory card must share this lower flap with the battery of the camera. The second flap is on the right-hand side of the Panasonic ZS70. Even if it only bears the HDMI lettering, the micro-USB interface is hidden next to the HDMI interface.

This is also used when charging the camera’s battery, as an external charger is not included. With the USB power supply, the camera is not choosy.

Equipment And Features

The equipment of the Panasonic ZS70 is extensive. Photographically, the camera offers aperture and time auto and a manual mode. If you don’t feel like it, you can choose the appropriate mode from 23 scene mode programs, and the camera then controls the internal settings from the recording to settings in the image processor.

The aforementioned scene mode programs cover a wide range of photographic possibilities with various portrait, landscape, night, and action programs. If this is too much work for you, you can simply set the intelligent automatic or “iA” for short on the rotary wheel. This functionality auto detects scenes automatically and adjusts the shooting settings accordingly. In addition, an “iA+” mode is available that allows manual adjustment of brightness and color.

In addition to the pure recording programs, there are also “Special Effects” available, which even have their own place on the ZS70´s upper function rotary wheel. With these presets, special effects can be conjured up in images without the need for subsequent image processing on the computer.

The spectrum of the 22 different effects ranges from the analog film inspired black and white and retro effects to dreamy filters that, for example, provide highlights with star grids. The ZS70’s function rotary wheel is then completed by a panorama setting, a configurable user setting, and a dedicated film function.

With the exception of the panorama setting, the photographer can go to the main menu of the camera at any time and, depending on the scene or effects program set, perform autofocus and individual functions, change to another scene or effects program, or change to one of the image styles. Image styles are basic image parameters that include contrast, sharpness, noise reduction, and color saturation. Image styles are available as defaults but can be edited by the photographer in the above-mentioned parameters.

There is also storage space available for your own image style. Image styles are also available in the video function.

Interesting is the 4K photo function. Although this uses “only” a fraction of the sensor resolution, it has the advantage of having the correct resolution for playback on a 4K television. For Panasonic, this function is so important that it has its own button on the back of the camera. By pressing this button, the photographer can activate the 4K Pre-Burst, which saves images before they are taken.

You can also select the Continuous Shooting function with Start-Stop function, where the photographer presses the shutter button once to start continuous shooting and again to stop continuous shooting. Or a “normal” continuous-advance function is selected that takes pictures as long as the photographer holds the shutter-release button down.

The post-focus function can also be found on a separate button. Like the 4K photo function, this function could already be found in the predecessor model but is still worth mentioning. This function allows the photographer to determine where the sharp area should be after shooting and then save it in a new image.

In addition, the camera can process the images captured with the function in a focus stacking and thus process them into a continuously sharp image.

The video function of the Panasonic ZS70 offers the photographer or better videographer a 4K resolution of 3,840 x 2,160 pixels and a frame rate of 24, 25, or 30 frames per second. The Full HD video function, i.e. with 1,920 x 1,080 pixels, even achieves up to 60 frames per second.

The so-called rolling shutter effect is present, but only minimally visible. The MP4 or AVCHD format serves as the video container. The video itself is encoded with H.264. The sound is recorded by a built-in stereo microphone and can be equipped with electronic wind noise reduction.

In addition, the Panasonic ZS70 offers a simulated “zoom microphone function”, in which the microphone level is coupled with the zoom process (but the actual recording characteristic does not change). While the camera warms up slowly in 4K video recording, it warms up much faster in 4K pre-burst.

The ZS70 offers the photographer a USB 2.0 interface and a micro HDMI interface for connection.

It becomes particularly interesting with the WLAN function of the camera. It not only allows the photographer to connect to the Panasonic app on a smart device, which allows the camera to be remotely controlled with everything around it and to add position data to captured images but also to integrate it into an existing wireless network as a drive. Panasonic offers the photographer significantly more possibilities to use the camera wirelessly than other camera manufacturers.

Picture Quality Of The Panasonic ZS70

Panasonic’s ZS series is one of the few compact camera series that still sell well. No wonder, since the compact housing contains an enormous zoom range that no smartphone could offer in 2017. After the update of this article in 2020, there were already smartphones that could provide this zoom range.

 

While the hardware already originates from serial production, the firmware of our test unit still has version number 0.1. This is a usual procedure, functionally and from the picture quality, this firmware already corresponds to the final state, and should no more bugs appear (we have not noticed any), the version number is simply set to 1.0 at market launch.

Compared to its predecessor, the Panasonic ZS60, the rear-exposed BSI CMOS sensor now resolves a full 20 megapixels instead of the previous 18. Both are actually too much for the tiny 1/2.3″ sensor.

In the past, Panasonic switched the ZS series (TZ series in Europe) from a high resolution to a low resolution and back again and again without any significant changes in the image quality. The reason for this lies in the compact superzoom lens, which has to fit into the four-centimeter flat housing despite the 30x zoom. This is a fine mechanical and optical masterpiece! The downside of compactness, however, is the low luminous intensity, which limits the resolution, especially in the telephoto range, due to diffraction.

Lens Of The Panasonic ZS70

That the ZS70 can’t keep up with cameras equipped with larger sensors and/or lenses with higher speed (and less zoom) is therefore obvious. The test with the testing software also shows this more than clearly.

The maximum resolution is a remarkable 54 line pairs per millimeter (lp/mm) in 35mm equivalent, but only with an open aperture of F3.3 in the center of the image in the wide-angle position of the lens. A slight loss of resolution already occurs when dipping down to F4 (see diagram from the laboratory test below).

At F5.6 the resolution already drops significantly to below 40 lp/mm, at the smallest aperture F8 it is just over 25 lp/mm. If you zoom, the initial opening is quickly reduced.

With a focal length equivalent to 135 mm, the maximum aperture is only F5.3, the resolution is just over 40 lp/mm in the center of the image, and at F5.6 as well, which is slightly higher than with the correspondingly dipped wide-angle lens. With F8, on the other hand, it’s barely 25 lp/mm.

In telescopic position, at 720 millimeters corresponding to 35mm, the initial aperture is F6.4, which is only sufficient for just over 30 lp/mm. After all, it’s barely below 30 lp/mm at F8. Considering now that one needs approximately 30 lp/mm in order to print a sufficiently sharp image in a size of 20 x 30 centimeters, it becomes clear that even the resolution in the image center is not always sufficient.

 

The situation at the edge of the picture is even more dramatic. In wide-angle, there is an enormous drop in resolution to around 22 lp/mm, at F8 even to 16 lp/mm. With a medium focal length, it is at least just over 30 lp/mm at the edge of the picture – at least as long as you don’t stop down further than F5.6.

In the telescopic position, the edge resolution is about 20 lp/mm. In the wide-angle and in the telephoto, the image corners are visibly blurred at 20 x 30 centimeters, only at a medium focal length, one can expose reasonably in this size. Therefore you better limit yourself to 13 x 18 centimeters, a good 20 lp/mm will be sufficient. 20 lp/mm is also sufficient for a presentation on a Full HD or 4K television.

The fact that such a large zoom in such a compact format always means a compromise becomes more than clear. Even the best image sensor can’t change this. After all, the camera corrects optical errors such as distortion, edge darkening, and chromatic aberrations very well, so that these errors can still be measured, but are practically irrelevant. However, there is one exception that is not covered by the measurement: The camera tends to bloom with strong contrasts, resulting in magenta-colored color fringes. With a desaturation of corresponding color channels, the effect can be masked quite well in image processing, if necessary with local masking, but becomes clearly visible without it.

 

Image Quality Of The Panasonic ZS70

The image quality, however, consists of much more than resolution and optical errors. The sensor and its ability to capture light and convert it into beautiful images also play a major role.

Correspondingly, the signal-to-noise ratio only reaches sufficient values, but not good ones. Up to ISO 200, the value is still above the critical limit of 35 dB, at ISO 400 and 800 it scratches, from ISO 1.600 it is below. However, the noise reduction ensures that brightness noise up to and including ISO 1.600 is only minimal. The value only rises slowly at ISO 3,200, but significantly at ISO 6,400, the highest sensitivity level. Color noise does not play a role up to and including ISO 3,200 but occurs at ISO 6,400.

However, the low noise also has its downside, as noise reduction is usually difficult to distinguish between unwanted noise and desired fine details of the motive. Above ISO 200, the level of detail decreases visibly, although ISO 400 still has sufficient detail. The images already look softer, but this only becomes clearly visible from ISO 800, where they look much softer, until at ISO 1.600 and 3.200 there are hardly any details left.

In contrast, noise suppression provides surprisingly good values for the input dynamics. This is because bright noise pixels are filtered out in a dark area, making the black darker. Up to ISO 200, eleven and more f-stops input dynamics can be measured, and up to ISO 800 it is well over ten f-stops.

Only then does the dynamic range decrease noticeably and go up to eight f-stops into the basement. The tone value transfer is only moderately divided, the output tone value range is good up to ISO 800 with 160 or more of 256 possible brightness levels. However, very good values are not achieved here, only at ISO 80 there are over 192 levels at all.

 

The color fidelity, on the other hand, is surprisingly good. Although one or the other color shade differs slightly from the original, there are no coarse outliers. Thus the pictures appear alive with somewhat more saturated warm tones, the cyan slightly shifted towards blue makes the sky blue more beautiful.

The actual color depth is very good with over four million colors up to ISO 400 and then starts to decrease. At ISO 800 there are still over two million good colors, at ISO 3,200 only less than one million and at ISO 6,400 even less than 250,000.

The DFD autofocus also does a very good job with the ZS70. At wide-angle, it takes just 0.16 seconds from pressing the shutter button to taking the picture. In telescopic position the time is almost tripled to 0.44 seconds, but the autofocus is not really slow here either. The pure release delay for pre-focusing is only 0.03 seconds independent of the focal length, a very good value.

The small image sensor on the one hand and the powerful zoom lens, on the other hand, set very narrow limits to the image quality of the Panasonic ZS70 (Panasonic TZ90 in most of Europe), as is usual in the travel zoom class.

The resolution suffers equally from diffraction during dimming and zooming. The optical performance at the edge of the picture is quite poor, especially at wide angles, which leads to blurred corners.

The image sensor provides good image quality only at low sensitivities. At each ISO level, this decreases significantly, which leads to slight losses even at ISO 200. But up to ISO 400 the images are still acceptable good, ISO 3.200 and especially 6.400 should be avoided as much as possible, as not much arrives in the image file, which could have been a colorful, detailed image.

The ZS70 achieves the highest resolution at open aperture and lowest focal length. Relative to a 35mm sensor, this is 54 line pairs per millimeter (lp/mm) in the center of the image. At the edges of the image, however, the resolution drops to 21.9 lp/mm, so that the blur in the edge areas is already visible on a 20 x 30 cm printout.

Due to the small sensor, the diffraction blur starts very early and limits the resolution characteristics of the lens. The camera delivers the most balanced results at a focal length of approx. 135 mm and an aperture of F5.3.

Although the maximum resolution drops here, the resolution increases in the marginal areas and the visible blur “disappears”. At maximum focal length and aperture F8, both the resolution in the center of the image and the edge areas decrease to such an extent that blurred areas are visible on a 20 x 30 cm printout. Only aperture F6.4 offers significantly better results here in the center of the image.

The ZS70 clearly shows that it is a “Shoot-to-Print” camera when sharpening the shot. In the wide-angle range and open aperture, sharpness artifacts can be clearly seen that only settle below ten percent just above aperture F4 (with the resolution, the sharpness artifacts also decrease) and then continue to decrease.

Sharpening artifacts are not a big problem in the telephoto focal lengths and the peripheral areas. The accuracy of ISO sensitivity is high.

The lens of the ZS70 shows only a small edge shadowing (vignetting) in the wide-angle range. In the middle “tele” and maximum “tele range”, the edge darkening is still smaller. Cushion and barrel distortions are neither relevant in the wide-angle nor in the telephoto range. The chromatic aberration, on the other hand, is slightly visible in the wide-angle range, but not in the telephoto range.