It might just be a lens that ends up incompatible. A condition like this seems like an engineering nightmare to correct and still not compromise other functions of the lens. Especially since it seems like it's an amplification of light directed onto the sensor from the aspherical lens element (why it's only on the outside of frame). I'm curious if they will be able to solve this problem in a practical way. I did reach out to Sigma and I am in the process of giving them raw files to examine and hopefully do their own tests. The flare rings are non existant in the 5D Mkiii or my 6D, so the shots would have looked similar, just minus the flare rings. No matter what settings are in camera for lens correction, or exposure, it's visible. The sample photos were shot with various fstops, I didint bother doing in depth comparison because this issue is present regardless of fstops, exposure or ISO. I can't see your aperture settings in the Exif?Īlso a 1:1 side by side test with the same scene and the same settings between the 5D mkIII and the R tested with different apertures (1.4, 8 and 16 for instance) and different placement of the light in the frame (out most corner, half way to the middle and in the middle for instance) would be the best illustration to show that this is a pure camera/adapter problem. I only have personal experience of the FE16-35/4 so I know how that one behaves in detail and it only does this between 16-23 mm (irrelevant for your prime) and only at smaller apertures (f16 etc) and only if the light source is near the center of the image. Several of the UWA zooms on Sony FE does the type of ring flare you got. The next focal length I really need to get is 35 mm and this sigma issue raises serious concerns for me getting the 35mm Art, because I have not seen any tests done with that lens and this camera where they're shooting back-lit. It has serious conflict with the either the adapter and or sensor on the EOS R. It's clearly the way they engineered the 24mm 1.4. I also have the Sigma 50mm 1.4 and that works just fine. There's nothing shiny inside the barrel of the adapter and nothing that should be causing that from any physical standpoint. You don't have to like my pictures, but it would help: Ĭorrect, the lens works perfectly on my 5D Mark 3. Like most camera tests, Sigma probably just mounted it and shot some indoor lighting and never even bothered to check real world conditions.ġ) Just for clarity, have you tested the same lens on a Canon FF DSRL and you get better results there?Ģ) How does the inside of the adapter look seen from the sensor side when the lens is mounted? Can you see any chrome parts? Are the black parts shiny or matt black?Ĥ2 Megapixels is the answer to life, the universe and everything. The most logical guess is that the lens was not calibrated correctly to the EOS R with the Canon adapter barrel. Both the lens and the camera are brand new. The adapter is perfectly clean and the lens is also. Testers holding the adapter and getting oily fingerprints on the inside barrel? Reflections off the inside barrel of the adapter? And the light is hitting the same Canon sensor. The end of the lens is in the same position with both a 5D mkIV and a EOS R w/adapter. I wonder what could possibly be causing this behavior. The only possible difference I can think of between the optical paths of a 5D IV and an R would be in the microlens array in front of the sensor, but this doesn’t look like a case of badly designed microlens either. That is a very interesting phenomenon, because an adapter with no glass in it like Canon’s should not exhibit any problem of this sort that doesn’t also manifest itself when attached to a DSLR.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |