By site editor Dan Chung
Electronic viewfinders (EVFs) are fast becoming a must have accessory for news and documentary shooters with newer cameras like the Sony F3, FS100 or Panasonic AF100. They can also be used to get a much clearer view of what is going on in the frame with some video DSLRs. They are essentially a mini monitor with a loupe attached.
At the NAB show this year Alphatron are showing their high resolution competitor to the popular Zacuto, SmallHD and Cineroid EVFs. Alphatron’s EVF-035W-3G main selling point is that it has a higher resolution along with both SDI and HDMI connections. The product is made in co-operation with established monitor manufacturer TVlogic.
The interesting thing is that the Alphatron display is a 960×640. 3.54 inch (diagonal) display which looks suspiciously similar to the one found on the Apple IPhone4S. When displaying a16:9 widescreen image the EVF will place bars top and bottom resulting in 960×540 pixels being used.
According to Alphatron this is significant because this resolution allows the EVF-035W-3G to downscale a HD 1920×1080 image with a downscaling factor or exactly 2. The resolution of 960×540 is exactly half of the full HD resolution which is 1920×1080.
Other competing displays with a lower 800×600 resolution have a greater downscaling factor of around 2.4. Because this is not a whole number Alphatron claim that there is a significant difference in picture quality.
Alphatron claim the downscaling factor of 2 is a ‘magic number’. This is what is says on their website:
“The EVF-035W-3G shows 1 out of every 2 pixels. However, if the downscaling factor is not an integer (i.e : 2.4 or 2.25), some of the horizontal and vertical pixels cannot be reproduced in a correct way. Hence, fine details, particular those for accurate focusing, cannot be reproduced.”
Other specs of the EVF are shown in this table:
The Alphatron seems to be a slightly bigger unit than my current Zacuto EVF and so it will be interesting to see how it really works at NAB 2012. Pricing has not yet been confirmed.
