SUPRA M74NG – tablet PC with 7″ IPS screen, 3G, satellite navigation, Android 5.1 and other functions for 50 USD

Tablet PC SUPRA M74NG
Tablet PC SUPRA M74NG

Company Supra recently released new tablet PC M74NG, having 7″ multitouch IPS screen ( with 1024 x 600 pixels resolution and 170 PPI density ), support of 3G connections, satellite navigation, Android 5.1 OS and other modern functions and costing around 50 USD. In it following is built in : 4-cores MT 8321 processor, working on 1.3 GHz frequency; 512 MB of RAM; 8 GB of built in memory with ability to extend via Micro SDHC flash cards with capacity up to 32 GB; and ability to use as cell-phone with 2 SIM cards. Tablet can work in 2G and 3G networks, without 4G support; GPS navigation, without GLONASS support and acceleration sensors are built into it.

Tablet PC SUPRA M74NG ( views from all sides )
Tablet PC SUPRA M74NG ( views from all sides )

Just for the check in SUPRA M74NG two cameras are placed : 0.3 MP frontal one and 2 MP main one; it can establish Wi-Fi ( IEEE 802.11 b/g/n ) and Bluetooth wireless connections for remote data transferring and communications with other devices. On external panels of tablet following modules can be found : USB port for connection with computer and other devices plugging via OTG; TRS 1/8″ mini-jack output for headphones; power switch and volume control buttons; and speaker, playing mono sound. It is bundled with Li-ion battery with 2600 mAh charge, which is enough for 4 hours of work; its body is made from plastic; device sizes are 188 ( width ) x 108 ( height ) x 10 ( depth ) mm and mass is 270 g.

Package contains : SUPRA M74NG tablet PC itself, USB cable, USB-OTG cable, recharger ( 2A and 5V ), 1-year warranty card and user’s guide. All in all for such money tablet is great; there is ability to wish for 4G, GLONASS support, larger RAM size and other functions, but price will increase accordingly with them. Manufacturer does not tell which graphical chip is used, if used at all ( maybe devices uses software rendering on its 4-cores CPU ), otherwise tablet is great for such money.

Behringer iStudio iS202 – iPad dock-station with advanced audio recording and playback functions

Behringer iStudio iS202 - iPad dock-station
Behringer iStudio iS202 – iPad dock-station

Among Behringer audio devices there is dock-station iStudio iS202 for Apple iPad ( 1, 2 and 3 generations ) with advanced audio recording and playback functions. Device can work from 2 A and 12 V power adapter or 8 AA batteries; on its top panel following controls are placed : buttons for phantom power +12 V switching for microphone inputs, Hi-Z mode switch for input 2 and AUX mode switch for inputs; separate knobs for amplification control of 1, 2 and AUX inputs; monitor mode switch for headphones ( 1, 2 and AUX inputs, signal from iPad ); volume control knobs of main outputs and headphones. On its frontal panel 1/8″ mini-jack output for headphones is located; on back panel there are : power switch button; power adapter input; composite video output; USB port ( probably, device can be used as external USB audio card without connection to iPad ); MIDI input and output; two TRS 1/4″ jack inputs for expression and foot switch pedals; 2 TRS 1/4″ jack main balanced outputs; ground connector; 2 RCA linear/AUX outputs; combined XLR/TRS 1/4″ jack output, which can work in microphone ( balanced ), linear and instrumental Hi-Z modes; another one such input, which can work only in microphone ( balanced ) and linear modes. On bottom side of Behringer iStudio iS202 there are batteries compartment and panel and holes for connection to instrumental stands.

Behringer iStudio iS202 - iPad dock-station ( back view )
Behringer iStudio iS202 – iPad dock-station ( back view )

Behringer iStudio iS202 connectors have following properties : microphone inputs ( gain in 25 – 55 dB range, maximal input signal level -7 dB, 2.6 kOhms impedance ); linear inputs ( gain in 0 – 30 dB range, maximal input signal 16 dB, impedance 40 kOhms balanced and 20 kOhms unbalanced ); instrumental input ( gain in 0 – 30 dB range, maximal input signal 16 dB, 16 MOhms impedance ); AUX input ( linear mode : amplification -infinity – 0 dB, +22 dB maximal input signal; phono mode : amplification -infinity – 52 dB, -40 dB maximal input signal; both modes : 47 kOhms impedance ); main outputs ( signal level -infinity – 6 dB, maximal output level 13 dB, impedance 240 Ohms balanced and 120 Ohms unbalanced ); headphones output ( signal level -infinity – 6 dB, maximal output level 16 dB, impedance 150 Ohms ). Device sizes are 305 ( width ) x 216 ( depth ) x 75 ( height ) mm and mass is 1 kg ( without power adapter, batteries and iPad ).

Package contains : Behringer iStudio iS202 dock-station itself, power adapter, 3-year warranty card and user’s guide. All in all device is interesting and has lots of audio connectors, part of inputs and outputs are balanced; however here is need to look on dock-station and external studio-level USB audio interfaces : it is possible, that such interface with similar ports sets of Steinberg, Behringer itself, Focusrite, Roland, M-Audio, ESI and other manufacturers production cost less. Their purchase is more suitable, because they can tightly integrate with modern DAWs ( FL Studio, Cackewalk Sonar, REAPER, Avid Pro Tools, Ableton Live, Steinberg Cubase and others ) via specialized drivers with ASIO 2.0 and Core Audio support.

Test-review of Mir-1V photo lens for M42 mounts on MFT sensor with crop-factor 2

Mir-1V photo lens for M42 mounts
Mir-1V photo lens for M42 mounts

I love optics, now I have 2 photo lenses : Mir-1V and Helios 44M-7 both are made in Russia and have M42 mounts for attachment to camera ( it has 45.5 mm work segment, with according adapters lenses can be easily used with all modern cameras, except of mirrored Nikon cameras, which have larger operating segment and require lens adjustments or mount thread modifications ); lets test first one of them to learn its strong and weak sides, optimal photos and videos making conditions and the most optimal settings for different environments. Lets begin with technical characteristics : it has 37 mm fixed focus distance, f/2.8 – f/16 diaphragm ( this is a middle light strength lens ), it is designed for 24 x 36 mm film or full-frame sensors, field of view is 60 degrees, minimal focusing distance is 0.7 m, 6 lens elements in 5 groups are built into it, they have yellow coating. My lens has 10 diaphragm blades ( 8 and 10 bladed variants were manufactured ), opening form is closer to circle, than of Helios 44M-7; standardized resolution is 45/23 lines/mm ( center/sides ). Lens length is 56 mm, maximal diameter is 59 mm, mass is 200 g; 49 mm optical filters and attachments can be screwed to it. It is copied from Carl Zeiss Jena Flektogon 35mm F2.8 lens; different modifications of Mir-1V were produced from end of 1950-ies.

Mir-1V photo lens for M42 mounts ( back view with partially closed diaphragm )
Mir-1V photo lens for M42 mounts ( back view with partially closed diaphragm )

On Micro Four Thirds sensor with crop-factor 2 field of view is reduced 2 times ( only central part of light beam is used ) : from one side this reduces field of view, from the other side this allows to use only central part of lens with lowest amount of aberrations and highest resolution and gives tele photo lenses in compact body. Photos, made with Mir-1V lens can be seen on this page : test photos of Mir-1V lens. Test video with counter and side lighting without YouTube recompression can be seen here : test video of Mir-1V lens.

Mir-1V photo lens for M42 mounts ( side view with control rings )
Mir-1V photo lens for M42 mounts ( side view with control rings )

Lens has diaphragm presetting ring, so that minimal diaphragm can be limited; however on sensor with crop-factor 2 there is no big need in diaphragming it. Diaphragm control ring made slightly unlogical in accordance to presetting ring : when mark is on minimal diaphragm value, it is fully open, when it is on maximal value, it is maximally closed; probably, this way it is easier to implement such mechanism; but there is ability to accommodate to it very fast and remember in which direction diaphragm opens and in which closes. Focusing ring has smooth and tight movement : everything is ok in this respect; lens can be screwed by its mini-blend and unscrewed by its focusing ring ( after setting it on minimal 0.7 m macro focusing distance ). Frontal glass is located deeply enough and closed by small blend on the sides, so on nature lens can be used without attachment blend.

Mir-1V photo lens testing, counter light, Sun in the center of frame
Mir-1V photo lens testing, counter light, Sun in the center of frame

Helios 44M-7 has small depth of field ( DoF ) and it is easy to focus it on object, even focusing on camera display; Mir-1V has larger DoF and it is harder to focus it on the object, it is better to use it with tripod. Also it has middle light strength and requires longer expositions, so, when photos are made from hands they can be blurred in motion, here tripod is also useful. Mir-1V has quite peculiar color reproduction : indoor and at cloudy weather it is even slightly “brutal” ( colors intensity is decreased further and dark parts become even darker ); at sunny weather color reproduction is natural. On sensor with crop-factor 2 it has no chromatic aberrations at all, even at sides; and it is good in counter and side lighting, however attachment blend is useful, when Sun is close to the border of frame.

Mir-1V photo lens testing, counter light, Sun at the top border of frame
Mir-1V photo lens testing, counter light, Sun at the top border of frame

There is need to learn to use this lens, it requires more work to be precisely focused and longer expositions; it should be used with tripod or there is need to learn to hold camera in hands so, that its shaking will be minimal. The other advantage : it has no electronics at all and its body is made from metal ( aluminum ), so it is much more resistant to shaking. All in all Mir-1V lens is very good, when used properly, and gives much better photos quality, than bundled kit zoom lenses wit large glasses amount of cameras; especially taking into account price, for which it can be bought.

Mir-1V photo lens testing, light, Sun close to the border of frame ( lens flares are visible )
Mir-1V photo lens testing, light, Sun close to the border of frame ( lens flares are visible )

Additional photos, made with this lens, can be seen in White Stone in December article. Here I just started to learn to use it and many of photos are blurred in motion, due to camera shaking. On the next week I’ll print test image, made its photos and add them to article with testing description and results. But even now there is ability to say, that lens will produce sharp photos even on open diaphragm, because it is used on sensor with crop-factor 2; the same way as it gives chromatic aberrations free image with such sensor. In January or February I’ll order macro rings and will test this lens in more macro mode with larger magnifications and on closer distances. If you have other propositions on this lens testing, then share them in the comments to this article, I’ll perform them, if they will allow to better unfold technical abilities of Mir-1V. In the next article I’ll test monster of soviet optics : Helios 44M-7 with 50 lines/mm resolution and aperture 2.

Mir-1V photo lens testing, light, Sun is further from border of frame ( there are no lens flares )
Mir-1V photo lens testing, light, Sun is further from border of frame ( there are no lens flares )
Mir-1V photo lens testing, chromatic aberrations, longitudinal ( trees branches and trunks without wind )
Mir-1V photo lens testing, chromatic aberrations, longitudinal ( trees branches and trunks without wind )
Mir-1V photo lens testing, chromatic aberrations, lateral ( tilted black letters on white paper ) + 70 cm macro photo
Mir-1V photo lens testing, chromatic aberrations, lateral ( tilted black letters on white paper ) + 70 cm macro photo

Update from 16.1.10 : here are photos of test mira for lens sharpness and geometrical distortions determination ( in article there are PNG parts of these images, originals are in album with rest of test photos ); mira is slightly rotated around lens optical axis and its right side is closer to camera, but there is ability to make conclusions. Firs of all, diaphragm 2.8 of lens is not usable at all, because even on sensor with crop factor 2 there is lots of soap even close to the center of image; diaphragms 4 – 5.6 give sharp images and are working values for lens, down to diaphragm 8 image is good, this value also can be used with tripod. Second, diaphragms 11 – 16 are also not usable due to very long exposures required and blurring, this time due to diffraction. So, here are additional conclusions : even on Micro Four Thirds sensors with crop factor 2 there is need to close diaphragm to 4 – 5.6 – 8 values and use these ones to obtain sharp images and videos without diffraction.

Mir-1V photo lens testing; diaphragm 2.8, center of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 2.8, center of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 2.8, right bottom corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 2.8, right bottom corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 2.8, left top corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 2.8, left top corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 4, center of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 4, center of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 4, right bottom corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 4, right bottom corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 4, left top corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 4, left top corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 5.6, center of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 5.6, center of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 5.6, right bottom corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 5.6, right bottom corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 5.6, left top corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 5.6, left top corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 8, center of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 8, center of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 8, right bottom corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 8, right bottom corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 8, left top corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 8, left top corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 11, center of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 11, center of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 11, right bottom corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 11, right bottom corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 11, left top corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 11, left top corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 16, center of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 16, center of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 16, right bottom corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 16, right bottom corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 16, left top corner of mira, sharpness and diffraction
Mir-1V photo lens testing; diaphragm 16, left top corner of mira, sharpness and diffraction