Are mirror less camera and lens systems superior?

newton · Joined: 10 Mar 2011 Posts: 343 Location: USA

I am wondering what the role of mirrors have in detracting from image quality, if at all, and if mirror less cameras are really superior, when considering the entire lens system.

scsambrook · Expire: 2011-11-18

Well, the moving mirror in a typical SLR plays no part in forming the image on film or sensor so it can't detract from quality - unless its action is so violent as to cause shake or vibration Very Happy

However, pellicle mirrors, which reflect some light into a viewfinder system and allow the majority of it to pass through to the film or sensor, could become dirty and so affect the image. That did happen with the old Canon Pellix back in the 1960s/70s.

The new generation of mirrorless cameras has advantages of compactness and lightweight, as well as allowing the lens designer potentially greater freedom in his/her (i.e the computer's) work.

RioRico · Posted: Sat Apr 02, 2011 5:17 pm Post subject:

For ultimate image quality (IQ), shun all mirrors, lenses, prisms, everything. Use a finely-made pinhole projecting onto a large-format frame. Oops, that is not convenient. So, use a film rangefinder camera with no mirrors nor prisms, just a good lens, maybe a 50/3.5 Elmar. Oh no, film isn't digital. So use a phone.cam, both digital and convenient, and to hell with IQ! Wink

No, as scsambrook said, the mirror (or lack thereof) has no impact on IQ. If it did, professionals in fields where IQ is critical would throw away their crop dSLRs and use only MILCs. Check the astrophotography and foresnics forums and see whether MILCs have taken over.

wupdigoj · Joined: 18 Mar 2010 Posts: 85

Mirrors have obviously no direct impact in IQ. However, they impose some restrictions in the lenses design: the minimun distance between the rear element and the focal plane. So theorically and specially in short focal lengths, mirrorless cameras have some advantage.

Javier

AhamB · Joined: 22 Jun 2008 Posts: 733 Location: Germany

What Javier is saying. The long register distance of SLR's force lens designers to make asymmetric "retrofocus" designs for wideangle lenses. I've read they're basically inverted telephoto designs. Apparently this makes it more difficult to correct CA and have good corner sharpness.

Lenses for mirrorless (one word) cameras or rangefinders don't have this problem, but for digital sensors they have another problem, being the very oblique angles of light which the sensor has trouble collecting from a lens that is very close to it. Leica/Kodak(?) has mitigated this problem to some degree with offset micro lenses, but there is still a problem with color shift, especially when you use Zeiss ZM or Voigtländer lenses on the M9.

Other mirrorless cameras such as the Sony NEX can get smeared corners at wide apertures with lenses of 28mm and wider, and varying amounts of color shift (cyan/magenta color cast in different parts of the frame).

jun · Joined: 25 Jan 2011 Posts: 54 Location: Philippines

am i missng something with regards to the use of the mirrors in traditional dslr?
the dslr has been around for a decade or so? why is it that it is only in the past 2-3 years did they eliminate the mirror?

was there a technology hurdle somewhere that prevented the mirrorless system?

is the viewfinder the only use of a traditional mirror system?

ManualFocus-G · Expire: 2014-11-24

Well, tradionally the main manufacturers hadn't produced electronic viewfinders and screens capable of keeping up with the action for a start.

RioRico · Posted: Sun Apr 03, 2011 10:55 am Post subject: Re: why only now?

AhamB · Joined: 22 Jun 2008 Posts: 733 Location: Germany