service manual required for EF 500f4 L IS USM lens

[Nickp]

I have some internal dust that I am wanting to clean out from my lens, but I could do with the manual to assist in the disassemble of the front section to clean off the dust that has built up

Thank

[TCampbell]

How much dust is it?  I ask because it is not possible for the camera to focus on dust in the lens -- it can't actually show up in an image.  A build-up of dust would eventually result in a loss of contrast, but not a loss in detail resolving capability.

If it's just a little dust, I'll suggest you do what we tell everyone in the astronomy community:  don't touch it!  You'll do more damage trying to "clean" it then you it could ever do if you just leave it alone.

If the dust build up is pretty significant... then I might want to clean it out, but for a 500mm f/4L lens... I'd send it off to Canon service for cleaning.  There's no way I'd try taking apart a lens that valuable myself unless I was so wealthy that I could afford to treat it like a disposable lens and prepared to buy a replacement lens. 

[Nickp]

Thanks for the advice and I have arranged for it to be serviced and cleaned by Canon as on reflection you are correct in your comments. It is a precision piece of kit

[RobertTheFat]

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@Nickp wrote:
Thanks for the advice and I have arranged for it to be serviced and cleaned by Canon as on reflection you are correct in your comments. It is a precision piece of kit

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Yeah, you'd be kicking yourself if you spent several hours cleaning the lens, only to discover that you had screwed up the focus or something and were going to have to send it in anyway. Canon may be expensive, but they do a good job. And if you have a lot of equipment, you can cur your repair costs somewhat by joining CPS.

[Nickp]

Thanks for the advice, i have contacted Canon and they are going to carry out a full service on the lens, and clean the internals thoroughly and reset it to as new condition. 

As you say, it's better to spend a few pounds than loose several thousand, appreciate the comments

Regards,

Nick

[ebiggs1]

You can certainly turm several thousand dollars worth of lens into a paper weight very quickly.