You’ve probably read plenty of articles touting the benefits of Sony’s translucent mirror technology (e.g. high fps, AF for video, quietness, etc…), but what about the cons? One of the main downsides to having a translucent mirror is that the light hitting the sensor passes through an additional layer (the translucent mirror), which reduces the amount of light and the image quality.
Ray over at TheSyberSite attempted to quantify how much the mirror affects the resulting image quality by removing the mirror on his A55 and comparing the resulting photos. He confirmed that about 1/2 stop of light is lost, and estimates that 5% of the detail in each shot is lost due to the mirror. Head on over to the article for some side-by-side comparisons.
Here’s an interesting look at the guts of the pellicle mirror Sony A55 and how the camera works. The camera being examined in the video is already disassembled and neatly organized by layer. If you haven’t seen or read much about the A33/A55 before, this video will bring you up to speed on the advantages of having a translucent mirror instead of a traditional one.
If Sony succeeds in this technology shift, it will be quite a change from the 1960s, when Canon introduced their version of the translucent mirror for film cameras but ended up going back to normal mirrors before long.
TIME magazine has named the Sony Alpha A55 as one of the top 50 inventions of 2010. They write,
A.K.A. the camera that never blinks. Traditional digital SLR cameras take the nicest photographs around, but they’re hobbled by a decades-old technical limitation: when you snap a picture, the mirror that’s been redirecting the image to your eye and to a focusing sensor pops up momentarily as the image is captured. Until it goes back down, the camera can’t focus. Sony’s Alpha A55 ($849.99 with lens) fixes that with an ingenious translucent mirror that stays put. That means you can shoot up to 10 perfectly focused photos a second and record HD video that never goes blurry. Bonus advantage: with no need to allocate interior space for a moving mirror, the Alpha is noticeably smaller and lighter than its Sony SLR brethren.
10 perfectly focused photos per second? That’s a pretty interesting claim.
Sony has issued an “important notice” that shooting HD video for semi-long periods of time with the A33 and A55 may cause the sensor to overheat, shutting off the camera. How long the camera lasts depends on ambient temperature and image stabilization is enabled. If it’s 30° C (~86° F) the A55 can only go 6 minutes with IS turned on. Read more…
Two advantages of the translucent mirror found in the Sony A33 and A55 are high fps continuous shooting (since the mirror doesn’t slow things down) and the lack of viewfinder blackouts when shots are being captured.
If you’re not sure what this means, the above video demonstrates what it feels like to shoot at 10fps using an A55. It kinda looks and sounds like you’re playing some sort of computer game.
The rumors that have been circulating in recent weeks were spot on: Sony has just announced four new DSLR cameras: the A33, A55, A560, and A580. As expected, the A33 and A55 are the world’s first pellicle mirror DSLRs, and have the features and specs we posted just yesterday: phase-detect autofocus while recording HD video or shooting 7fps or 10fps respectively. Read more…
The above is supposedly a leaked photo of the not-yet-announced Sony A33 and its pellicle mirror, the first of its kind on a DSLR. Rumor has it that the camera will officially be announced early tomorrow morning.
Sony is set to introduce shooting speeds of up to 10fps, as well as video, in its latest Alpha DSLR cameras, the Alpha 55 and Alpha 33, by using a new non-moving ‘translucent’ mirror. Echoing the technology of the pellicle mirror in Canon’s EOS RT of 1989, Sony’s new semi-transparent mirror allows light to be fed simultaneously to a camera’s imaging sensor and AF system, removing the need for a moving mirror and providing the potential for much improved focus tracking as well as active AF in Live View and video modes.
Alleged photographs of the upcoming Sony Alpha A33 and A55 DSLR cameras have popped up in an overseas forum. The images look legitimate, though the A55 and A33 front views are identical images that had the model number Photoshopped. Not sure why that is.
Here’s what the next couple weeks are going to look like in terms of press events possibly related to DSLR announcements: Nikon goes first on August 19th, Sony does theirs on August 24th, and Canon has one scheduled August 26th. Nikon will likely be announcing the D3100, while Canon drops the 60D during theirs.
A big rumor regarding Sony’s upcoming unveiling is that they’re going to be showing us the world’s first pellicle mirror system on a DSLR camera. This means instead of a traditional bulky mirror that swings out of the way — as found in current DSLRs — the Sony DSLR will have an ultra-thin and ultra-lightweight semitransparent mirror that allows photos to be shot without the mirror swinging out the way. Read more…