OM-D E-M5 vs E-5 (build quality)

Started May 13, 2013 | Discussions thread
boggis the cat Veteran Member • Posts: 6,329
These aren't results from 'cropped' lenses

Sergey_Green wrote:

philosomatographer wrote:

The fact of the matter is, as we get access to higher-resolution sensors, the SHG lenses show undeniable optical superiority over the best that Nikon, Canon, and Zeiss/Sony have produces thus far. That's why they are so expensive, that's why they are so large in relation to the sensor, and that's why we put up with the limited, small sensors of this system.

Whether it will or will not remains to be seen, but generally 2/3rds frame will extend deeper into the corners than the 4/3rds frame, and it is hardly unusual to occasionally see softer in comparison to he rest of the frame corners. The 4/3rds simply crops those extremes off.

If you are mounting a lens designed for APS-C (or 135) on FT, then it gets a centre crop.  But for native FT lenses the design takes the 4:3 ratio into account, so the vignetting performance is as intended (and also distortion, CA, etc).

IIRC, the Zuiko SHG lenses were supposedly designed to yield a full resolution gain out to around 20 MPixels -- i.e. the sharpness should be sufficient out to that limit.  Probably assumed to be a huge capability at a time when pixel counts were only just getting up to the 8 MPixel mark.  Now it seems likely that the SHG design will be exceeded within two or three years, perhaps five at most.

(Although the pixel size will be getting too small at this density on the FT sensor, IMO.  Perhaps the manufacturers will relent from pursuing the pixel count when there are no real benefits to be gained and work on more useful areas.)

BTW - Sergey - note the complete lack of visible light falloff. The Tamron you've been promoting as being "equally good on full-frame" has 2.7EV light falloff in the corners at this aperture (2.8) - despite the modest "1 stop" you claim (see e.g. the LensTip tests), and comes nowhere near this ability to resolve small details in difficult light with this level of perfection. If you don't see it, you are ill-equipped to be commenting on these matters.

There is optical vignetting, and there is pixel vignetting, and because you may see occasional darker corners does not necessarily mean that the lens "did" it.

Are you referring to telecentricity issues?

I thought that the usual argument was that the FT telecentricity design aim was irrelevant given that other manufacturers use offset on-sensor micro-lenses to correct for this issue?

(If this is still an issue then my understanding of this is wrong.)

I personally do not see it a drawback when shooting wide open. As I said above, you simply get cropped off corners on the more square looking (4/3rds) frame. Many compacts take great advantage of this same format as well.

4:3 is a more efficient use of an image circle than 3:2 -- but, again, if you are discussing lenses designed for the sensor (and thus the aspect ratio) then there is no 'cropping advantage'.

 boggis the cat's gear list:boggis the cat's gear list
Olympus E-5 Olympus E-M1 Olympus Zuiko Digital ED 12-60mm 1:2.8-4.0 SWD Olympus Zuiko Digital ED 50-200mm 1:2.8-3.5 SWD Olympus 12-40mm F2.8 +7 more
Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow