EF-M 15-45 ... sometimes soft side of the image

Started 2 months ago | Questions thread
KevinRA Contributing Member • Posts: 644
Re: EF-M 15-45 ... sometimes soft side of the image

davev8 wrote:

KevinRA wrote:

davev8 wrote:

KevinRA wrote:

toomix wrote:

I know, a lot of debate has been done about this lens. In general, I'm happy with it but I have noticed that sometimes (maybe 30% of the cases) it has left side of the image rather soft. There is no pattern in focal length, aperture, or focusing distance ... does anybody experience the same issue, please?

Other shots are perfectly sharp ...


Try shooting 45 degrees like a newspaper - and see if the depth of field is linear or if the lens is tilted. If slightly tilted, the large depth of field may mean that the image is sharp across the frame in some shots if optimum focussed but not in others. Another test is to set up objects a different distances from the camera across the frame - is the plane of focus a constant difference? I have this issue to a slight degree in my 15-45 (I tolerate it) but not as bad as a sigma 56mm at f/1.4, a canon 15-85 (which was bad even at f/8) or more surprisingly a 2nd hand 60mm macro.

would not decentering be easier to spot if the camera was set up perfectly square on a tripod to say a news paper taped to a wall with the lens wide open ???

Works well for a f/1.4 lens to see if a problem but wont diagnose it the cause and may not be repeatable in slight tilt case. The OP here says 70% of the time their lens is OKish at least. Depth of field depending on focussing may be enough to cover a slight tilt depending on exact focus point - whereas a test looking at where the optimum focus point is should diagnose the issue. E.g. is the plane of focus not flat - or in a true de-centred lens, is the left side soft however focussed.. The latter always an issue, the former YMMV... Just looking at the OP's problem.

i think if you have a lens that its decentering is hidden at F3.5/wide open you will never notice it in real world photos ...if you got very technical at looking for it you probably want find any cheap kit lenses that are perfect

I'm sure to a degree you're right, but have tried this casually on plenty lenses in time - and most seem to "pass" for me Ok including the old kit EFS-18-55 I had....

Out of all the lenses I've tried, only ones with issues have been canon 15-85 (even at f/11), sigma 56mm f/1.4 (fine by ~f/4), sigma 10-20 (dreadful, long time ago), 16-35L (at > 28mm but OK at f/9ish) and just lately a canon 60mm macro (used copy and looks like decentring not tilt I think). My 15-45 EF-M is not far off (and neither was the 1st copy I had to return as was part of a faulty M6II kit).  All others never noticed a problem at all.   The 56mm for example fails a brick wall test - but actually is fine in most use - as normally at wide apertures only the subject (e.g. part of the frame) is in focus anyway - so even if at edge of frame then fine. The 10-20 though would require a stack, even to get a sharp shot at f/11 cross the frame.

Try some tests and see?


 KevinRA's gear list:KevinRA's gear list
Canon EOS 5DS R Canon EOS M3 Canon EOS 5D Mark IV Canon EOS M6 II Canon EF 200mm f/2.8L II USM +13 more
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow