I have an eos R and I got a refurbished 24-70 f4 from the Canon website for Christmas and I’m having trouble with the sharpness and focus of the lens. Has anyone had trouble with refurbished lenses before? I’m so disappointed because I was so excited for an L series lens but I feel like my old 50 1.8 is getting better focus.
Hello and welcome to the forum. I guess that not all "L" lenses are created equal, but you should be getting decent results. I have EF lenses that I use on my R mont camera, and they work seemlessly. What EF to R adapter are you using? I have never brought anything from Canon refurbished. but I would be thinking about sending it back. Gary
Welcome to the forum Kandice, if after a day or so you have not found a solution I suggest you direct your quirey to Johnsey as he is very switched on in this area.
Few thoughts here, your Eos R uses the sensor instead of the mirror for focus, so focusing should perform great regardless of lens. If you had a DSLR I would wonder if they sent a lens used out of tolerance or if you could use micro adjustment to correct the softness, this all does not apply to mirror-less. The 24-70 should outperform the nifty fifty especially wide open. I think some examples would help where you point to what your seeing, but web sized crops can also only be so helpful. I would try to narrow if your having a focus problem with just this lens or if it is indeed a soft lens. In any event, if you have a return policy with canon on the referb I would start the conversation about sending it back, you likely have a small window to decide to do so, they could probably send you a different copy and you can identify if it was the lens itself.
Thank you everyone for responding. I finally was able to do some example shots. These are both shot at f 4.5, 1/500, iso 2000. The first is with my nifty 50 and the second with the 24-70 f4 and are SOOC except I did enable profile corrections in LR on both. I focused in my daughters left eye for both images.
Thank you everyone for responding. I finally was able to do some example shots. These are both shot at f 4.5, 1/500, iso 2000. The first is the my nifty 50 and the second with the 24-70 f4. View attachment 11449
I can't really see much difference with the images that you have posted. I am not doubting you as once you have resized the images for the forum, the difference may not that easy to see. I don't own either of the lenses that you are using. So I went searching on the net and I had a look at the lab tests that have been done on both lenses. And indeed, the 50mm f1.8 prime is sharper than the L lens at f4.5. I was a little shocked to be honest with you. But that is what the test results are showing. I can't really advise you what to do with the 24-70 f4. I know if it was myself, I would not be that happy with it, and I would look at exchanging it for another model of Canon lens, or getting a refund. Yes, it is a more flexable lens than the prime, but if it is not showing you the sharpness you are looking for........... Gary
The problem with these images is that they are too small to evaluate sharpness. They need to be at least 2000-3000 pixels wide to be of any use. Could you please upload larger images?
When you take your next photos Kandice can you take a picture of a ruler / tape measure strip at 45 ish degrees specifically focusing on a number to see if the set up is actully focusing where you think it is.
Thank you everyone for your input and suggestions so far. When I uploaded my photos I tried to upload the original file but it said there was a limit of 1MB so I had to upload a medium size file to be under that size requirement. Am I doing something wrong there? And I will take some photos with a tape measure today but I don’t know what you mean by 45 degrees, I’m sorry I haven’t done any of this stuff before and don’t know what I’m doing. Thank you all so much!
Image size, I did not realize we have a 1mb limit, i know we had a pixel dimension limit, the settings on the back end may have been tweaked to help with space savings. In any even your re-size was so small it as only 60kb and can only be viewed at a small size, you could share a much larger image before getting to the size cap. You could also upload elsewhere such as Flickr or Dropbox and link to the images if they are full res copies. Regarding the 45degress thing.. the nature of that was a lens sharpness test. You can search google for a few articles on what you can do. One thing would be to just shoot a chart straight on lined up while taped to the wall so the chart fills the frame, and use your center focus to see how sharp it is when you are controlling everything this should show how sharp the lens actually is. Mentioning the angle shot with a tape measure... you could shoot a ruler or chart with ruler on it at an angle and identify if it was back or front focusing and see if it was something that could be fixed by micro adjustment; lenses have a bit of tolerance the factory considers acceptable which is why DSLR have micro adjustment in them. Again being mirrorless I don't see this being applicable since the AF system is focusing off the sensor and should be hitting consistent focus regardless. But you could give that a try as well and see what you get. The raw file tells where the focus point is, so you want to go dead center in your testing to use the sharpest part of the lens.
lay the tape measure out like 80 cm on a flat surface, with the 0 at the top and the 80 at the bottom of the frame, set the lens to wide open and focus on the 40cm mark holding (or tripod) the camera at 45% or shallower so you get a sharp focus point where you aimed then it should go out of focus as it goes away from the focused area. if the 40cm (what you focused on) is not the sharpest of the image compared to the rest then something might be amiss. normally you do this to adjust the focus points of a mirror camera, not needed with mirrorless but at least it will see if you are getting what yu aimed at, you might have unfocused eyes and need to alter the diopter (the +/- thingy) on the view finder
Just to give you an idea of what I mean about image size. This image is 2048 X 1366 pixels and is 417KB but at full size the sharpness is very evident and this was taken with a Canon EF 28-80 low level kit lens which preceded my better glass. But decent images can be gotten from kit lenses if you work at it. Just click on the image to view at full size which is nowhere near the size limit. There is no need to upload an image straight from the camera.
Did you use a tripod while taking your separate evaluation photos? Be sure to use one if you follow through with the tape measure or chart photos. This will help you perform a fair comparison. Or just do not drink any coffee that day
