dust in Canon 100 - 400 mark ii (1 Viewer)

[Steve Babbs]

Hi all

I've just noticed how much dust is behind the objective lens on my lens. Considering it is about 8 months old and I haven't actually taken it anywhere that dusty this seems pretty crap to me. Have others got this problem or do I just have a Canon lens jinx? (My mark i had the AF fail in just over a year and then the IS failed about a year later but I suspect it had less dust in it.)

Regards

Steve

 

[lewis20126]

crikey, that is a worry - not really checked mine but will do now..

The old 100-400 was known as the dust pump.

cheers, alan

 

[johnf3f]

Any zoom that extends will, potentially, suck in dust regardless of whether it is twist of push-pull.
In 5 1/2 years my "dust pump" failed to pump dust but others were not so lucky.
It almost certainly will have zero effect on IQ so I wouldn't worry too much.

 

[RonW]

I had the same problem, lots more dust than the old version. I had mine cleaned (for free) by Canon after I had it for four months and checked to make sure all rings were fine. Looks like it is less of a problem now, but time will tell.

 

[ternaround]

I've had the original 100 400 for 9 years and not a speck of visible dust in it, I still prefer the original lens.

 

[lewis20126]

I've had the original 100 400 for 9 years and not a speck of visible dust in it, I still prefer the original lens.

Do you take it out of the box?

cheers, a

 

[johnf3f]

Do you take it out of the box?

cheers, a

Not all "Dust Pumps" pumped dust - mine was a complete failure!
I wish the Mk2, with it's superior optics, was a trombone action like the old one! I find the twist zoom to be much slower and less well balanced with an extending lens - though most seem to prefer this mechanism.

 

[bob freeman]

Not all "Dust Pumps" pumped dust - mine was a complete failure!
I wish the Mk2, with it's superior optics, was a trombone action like the old one! I find the twist zoom to be much slower and less well balanced with an extending lens - though most seem to prefer this mechanism.

Fully agree with you on that one John,it was much easier and quicker to zoom in and out with the old Mk1 lens and folk (including Canon me thinks)thought going to the twist zoom action would stop the Dust Pump effect.
How wrong they turned out to be 🤐

 

[johnf3f]

Fully agree with you on that one John,it was much easier and quicker to zoom in and out with the old Mk1 lens and folk (including Canon me thinks)thought going to the twist zoom action would stop the Dust Pump effect.
How wrong they turned out to be 🤐

I can't comment on the new version - never (yet) owned one! But I would love to have the new (MK2) optics in the old (Mk1) lens barrel and no IS = sweet!

By any standards the 100-400 Mk2 is a better lens than the Mk1, it is just that I think it could have been even better if it retained the same barrel construction of the Mk1. Maybe I am weird, quite possibly, but push-pull zooms are far more intuitive, faster operating and better balanced for me. Having said that it is quite likely that I am going to buy a 100-400 Mk2 so I am willing to put up with the poorer ergonomics of the Mk2 for the better glass!

As to the twist versus trombone zoom? Any zoom lens that extends will such in air and dust - simple physics. The twist zooms may (?) suck in less dust but that is only because they are slower to zoom so the seals get a better chance to work. I want speed so that's why I prefer the push-pull/trombone action.
P.S. All the old Canon FD manual focus 70-200 F4 lenses that I have tried/owned didn't suffer from dust - so it can be done.................

 

[Steve Babbs]

and I thought I was the only person who actually liked the old push-pull zoom! I do think that there should be better dust sealing in what is - by 'normal' people's standard - an expensive bit of kit.

 

[john miller]

Have had the mk2 for about 6mths, still when something suddenly appears try to pull the lens out instead of twisting. Mk2 a far better lens, if only they had kept the push-pull. Never had a dust problem in 10yrs with the mk1.

John

www.kellingnature.zenfolio.com

 

[Dave Boyle]

Hope its ok to revive an old thread but this seemed like the best place

I took my Canon 100-400 mkii in to be cleaned last week, its sucked in lots of dust over the years & there's now fungus growing inside - it came back straight away & they won't touch it, saying its not economical to clean. So I just wanted to warn people it might be worth getting their lens cleaned fairly regularly if they start seeing dust &/or fungus & not leave it too late.

You can find everything on YouTube so next week I'll be taking it apart & giving it a go myself - has anybody ever done this? Taking off the objective lens looks pretty straightforward at least & I'm kind of thinking I probably can't make it any worse! Incidentally, in one of the YouTube videos the fella says he's never known a lens suck in as much dust as the mkii 100-400

 

[Steve Arlow]

I had to send my 100-400mm mkii to Canon for a clean last month due to excessive dust on the inside of the objective glass. This was following trips to Israel and Texas so environments were pretty dusty but even so I expected better dust proofing than this. As it was just outside of warranty I had to stump up for the clean.
Wish these lenses were all internal zoom as that would resolve the sucking in of excessive dust.

 

[Dave Boyle]

I had to send my 100-400mm mkii to Canon for a clean last month due to excessive dust on the inside of the objective glass. This was following trips to Israel and Texas so environments were pretty dusty but even so I expected better dust proofing than this. As it was just outside of warranty I had to stump up for the clean.
Wish these lenses were all internal zoom as that would resolve the sucking in of excessive dust.

Taking the objective lens off is pretty straightforward, all you need is a good PH00 screwdriver (don't use a cheap one because you'll chew up the screws), a pair of tweezers & a suction cup to lift the lens out (I used the one you use to stick a satnav to a windscreen). Then, for me at least, just using a rocket blower I easily got rid of all the visible dust on the lenses - the inside of the barrel is sticky, I guess designed to trap any dust that gets sucked in, but it doesn't seem to work very well!

I think to make everything internal you'd end up with a huge lens that would be far less practical but the mkii doesn't seem to be any better than the mki for sucking in dust

 

[DoghouseRiley]

Did you have it attached to the R7? It isn't weather proofed to any standard.