Hi all!
I have encountered a following problem. Brand new R5 and brand new RF 35 with or without the newest firmware produce a terrible back focus for apertures above 1.8. At aperture 4.0 the back focus is the worst, resulting in the least acceptable resolution in the point of intended focus. I have also tried another copy of rf 35 and the problem persists. This problem sometimes vanishes by itself for no reason and the camera works well until shutdown. I have tried all kinds of settings to find out what might trigger it, firmware updates, all kinds of AF and modes- nothing helps. The only way I can achieve normal results is to mount a 50 mm 1.2 rf first ( flawless work) and then change it to 35 mm without turning off the camera. For some reason it will do a trick and a camera fill hit the focus at any aperture after that until shut down.
I attach a link with a couple of center crops of the target. They are both shot from a tripod at 1/1000 a second, AFS stabiliser off ( but nothing changes if it is on), aperture 4.0, iso 1600 ( yes ISO is high, no if you set it to 100 nothing changes), distance to a target is around 3 meters. One photo is taken after changing a lens from 50 mm, the other straight after I restarted a camera a moment later.
I also attach a center of a shot made at 1.8 aperture which is clearly sharper than the one made at 4.0 after the restart.
Why am I sure that is is a back focus? Because I ran several photoshoots and always saw focus on ears rather than on eyes. And because I tried gazillion shots on a ruler and I clearly see a problem.
What am I asking? I am asking the ones who have this combo to test it and see if the same thing happens. Just pick any target with small text on it like some package and shoot it in AV mode from a tripod or any steady surface at 1,8 and 4,0 apertures and watch if the resolution of the text downgrades.
What I am NOT asking for. Please do not advise to change my shooting technique or make any assumptions unless you do the test yourself. I made this test numerous times accompanied by a technician in a camera shop and I DO manage to achieve perfect results with other lenses or straight after changing the lens from 50 to 35 until I switch the camera off. I also tested another lens in another shop, same result. I already contacted an authorised Canon technician and will take the combo to him on Monday so you will have nicer pictures at 100 ISO, rulers etc.
I do know the Optical limits review, where they stated that 35 rf is prone to focus shift. The focus shift that they illustrated is incomparable to the one I get. Mine results in OOF images where at the sweet spot of the lens you get the worst results.
The crops form undedited raws are attached via the link
LINK REMOVED BY MOD_1 as we don't know the safety of the link.
I have encountered a following problem. Brand new R5 and brand new RF 35 with or without the newest firmware produce a terrible back focus for apertures above 1.8. At aperture 4.0 the back focus is the worst, resulting in the least acceptable resolution in the point of intended focus. I have also tried another copy of rf 35 and the problem persists. This problem sometimes vanishes by itself for no reason and the camera works well until shutdown. I have tried all kinds of settings to find out what might trigger it, firmware updates, all kinds of AF and modes- nothing helps. The only way I can achieve normal results is to mount a 50 mm 1.2 rf first ( flawless work) and then change it to 35 mm without turning off the camera. For some reason it will do a trick and a camera fill hit the focus at any aperture after that until shut down.
I attach a link with a couple of center crops of the target. They are both shot from a tripod at 1/1000 a second, AFS stabiliser off ( but nothing changes if it is on), aperture 4.0, iso 1600 ( yes ISO is high, no if you set it to 100 nothing changes), distance to a target is around 3 meters. One photo is taken after changing a lens from 50 mm, the other straight after I restarted a camera a moment later.
I also attach a center of a shot made at 1.8 aperture which is clearly sharper than the one made at 4.0 after the restart.
Why am I sure that is is a back focus? Because I ran several photoshoots and always saw focus on ears rather than on eyes. And because I tried gazillion shots on a ruler and I clearly see a problem.
What am I asking? I am asking the ones who have this combo to test it and see if the same thing happens. Just pick any target with small text on it like some package and shoot it in AV mode from a tripod or any steady surface at 1,8 and 4,0 apertures and watch if the resolution of the text downgrades.
What I am NOT asking for. Please do not advise to change my shooting technique or make any assumptions unless you do the test yourself. I made this test numerous times accompanied by a technician in a camera shop and I DO manage to achieve perfect results with other lenses or straight after changing the lens from 50 to 35 until I switch the camera off. I also tested another lens in another shop, same result. I already contacted an authorised Canon technician and will take the combo to him on Monday so you will have nicer pictures at 100 ISO, rulers etc.
I do know the Optical limits review, where they stated that 35 rf is prone to focus shift. The focus shift that they illustrated is incomparable to the one I get. Mine results in OOF images where at the sweet spot of the lens you get the worst results.
The crops form undedited raws are attached via the link
LINK REMOVED BY MOD_1 as we don't know the safety of the link.
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