New 85mm f/1.8 Very soft to 3.5

<p>Just got a new 85mm 1.8 and have been testing it. Seems very soft from 1.8 to 2.8, but tack sharp at 3.5 up. My 50mm f1.4 performs a lot better from 1.8 to 2.8.</p>

<p>I've seen sample 1.8 shots online for this lens and they seem a lot better than what I'm getting. If I take this to the Canon repair center in Jamesburg, NJ can they somehow improve the wide open performance w/o sacrificing IQ stopped down?</p>

<p>Also check out the reviews at Photozone.de for some comparisons ( <a href="http://www.photozone.de/canon_eos_ff/419-canon_85_18_5d">on 5D</a>, <a href="http://www.photozone.de/canon-eos/164-canon-ef-85mm-f18-usm-test-report--review">on 350D</a>) to see if your perceptions are correct.</p>

<p>Are you sure you have good focus. 85mm and f1.8 needs accurate focus. Try focus bracketing using manual focus. If there is an AF issue, it can be fixed, but the repair will be different than if it's an optical issue.</p>

<p>The 85/1.8 is amazingly sharp. See <a href="http://www.bobatkins.com/photography/reviews/canon_ef_85mm_f18_review.html">http://www.bobatkins.com/photography/reviews/canon_ef_85mm_f18_review.html</a> for some image samples and comparison shots.</p>

<p>If it's out of spec for some reason (e.g. misaligned element), fixing it will improve performance at wide apertures. It will not reduce performance at smaller apertures.</p>

 

<p>I'd be 90% sure that you're dealing with a focus calibration issue and not a "soft" lens. I've not seen any complaints that I can recall about poor performance from this lens and the two different copies I had were both amazingly sharp, even in the wide open apertures.</p>

<p>Mine was very good at F1.8 whereas my 50 1.4 was terrible. You probably need calibration. Monkey with the MA on your camera and see if your can improve it. </p>

<blockquote>

<p>My 50mm f1.4 performs a lot better from 1.8 to 2.8.</p>

</blockquote>

<p>I agree with the others: your focussing is probably off. Try Live view and see what the sharpness is like after manual focussing. The 85/1.8 is better than the 50/1.4 from 1.8 to 2. At 2.8 they are about equal.</p>

<p>Mine was very good even WO, I'd suspect you need to do a MFA for this lens. Also, do you have more than one body to test it on? you may find very different results from different bodies, esp. WO.</p>

<p>I tested on a 7D and a 5D Mark II, same results but 5D performs slightly better. It was on tripod with mirror lock and 2 second timer. What's really odd is f3.5 is always sharper than f4.5 on the 5D. I took several pics at each f stop just to account for AF issues. I'll take it to Canon next week. If that does not work, I'll send it back to B&H for a better copy.</p>

<p> </p>

<p>FWIW I have the 85mm f/1.2 L lens and had a micro-focus adjustment performed on both my 5D Mk II and 7D to "zero in" the optics to the bodies.<br>

Calibration results were 5D Mk II: +2 and 7D: +4. Wide open, anything greater than ± 2 at that focal length will be critical and will appear as "soft" focus.<br>

Get the instructions on how to perform MFA first, then run the test before you return the lens for repair.</p>

As Sheldon points out have you fine tuned your camera bodies autofocus for this lens? To really check the lenses

performance : camera on tripod, manual focus, and live view to focus with. If it is still soft it is a bad lens. If ithe results

are crisp you need to fine tune the AF performance for the specific individual camera + lens combination.

<p>I also agree with the others - my 85 F1.8 is a little soft at F1.8 but from F2 is great, my 50 F1.4 does not get really good until F2.8 and even then my Contax 50 F1.7 is better. Either it is technique, micro adjust or a bad lens copy.</p>

<p>If you download the latest Canon DPP versions they have an option to show the AF point. You can download it from usa.canon.com go to the downloads for the Canon 1DS Mark IV (get the update for DPP from the latest model - they are all the same but they only put the newest versions under the newest models for some silly reason). Then take a picture wide open (make sure the lens is set to AF and not MF (not trying to insult here, just trying to help), look at the picture with DPP and right-mouse click and select AF point. It will show the squares of your AF points and it will light up the one used in red.</p>

 

<p>why not post pictures of what you're referring to as "soft?" ALL lenses are soft wide open. I've used the 85 f/1.8 before and it is not soft at all.</p>