Canon 28-7-L 2.8 auto focus problem

[gary_deschenes]

<p> Just want to know if anyone out there has had a Canon 28-70mm 2.8 Lens have auto focus problems that needed repair and if so was/is it affordable. I have a daily user on my 5D and the auto focus has decided to work when it wants and at that the shots are blurry. Switch to manual there sharp. I popped the lens on my friends 5D and the problem followed so I think its the glass and his Canon 24-70 on my 5D worked flawless for the time he allowed it on my camera. As well, I have the BG-E4 grip with dual Canon BP-511A's but the camera's dead within two days even after no use. (I always shut it off but coincidentally this and the lens issue all seemed to start happening about the same time). I guess maybe the batts have had it but wonder how long could/should one expect them to last - these have seen the better side of 4 years... maybe time for new. Maybe someone out there has seen this and I have bigger problems than I think (like getting the Mark II). Thank you in advance, its a great forum and I always learn so much here.</p>

[MathewDH]

<p>Hi Gary,</p>

<p> I bought a used little used 24-70 a few years ago on Ebay and it still serves me well. Now don't laugh, I bolted it onto my Canon 300D and have used it also on my 10D IR converted. I like to do stitched panoramas and hope someday to be able to afford a new body with a full frame sensor.<br>

It sounds like you need to have it rebuilt. The best way to find out the cost is to contact Canon. It might be a lot cheaper than buying a new L lens. In fact you may find the lens just needs cleaned and serviced. As for batteries, normally they have about a 100 recharge cycles lifespan. I do not do a lot of shooting so they last me longer but they still fail after so many charges. I now have some unused Quantrary batteries as backups since my two original Canon marked batteries have died. If your batteries are being used a lot then you will go through them pretty fast. I found with my camera that a dying battery failes to put out a good enough charge and some photos will show a darkened distorted picture. So that is a indicator they are dying. Another indicator is a drained battery taking little time to recharge - meaning it is not charging very much at all.<br>

When it comes to sharpness, digital is not it. Part of it I read has to do with the sensor system on the Canons but another part is the algorythm that converts the RAW files to tiff images. It leaves a soft image. Hence the need for a refocusing plugin like Optipix. Once I do an upgrade to CS5 in a month or two, I will be adding this plugin for that purpose. I dislike the effects from using a sharpening tool on images and have to be very carefull about not making it look like a crappy jpg.<br>

So where are you at, and what is your favorite subject to shoot?<br>

CHEERS...Mathew - Port Angeles</p>

[AlRohrer]

<p>I have a Canon 28-70 f/2.8 L that started to get a little soft as it aged. Can't remember what you call it but there was a part that needed replacement and it is common with this lens. Cost just over $100.00 and it has worked like new since on all of my cameras.<br /> Good luck,<br /> Al</p>

[gary_deschenes]

<p>Mathew, Al - Thank you for your reply's. Lens is off to Canon for repair.</p>