How to clean a flourite lens?

[canonlover]

Is there a particular way that I should be cleaning a flourite lens, as opposed to a standard non-L series lens?

 

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My camera dealer told me I shouldn't really use a compressed air cleaner on a flourite element as it can damage the coating. He suggested using a cloth and/or a blower brush instead.

 

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Is this reasonable advice to follow?

 

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Also, how should I clean the mirror and underside of the focussing screen on my EOS 30/Elan7E?

[Ken Katz]

The flourite and UD elements are inside the lens. I have never used

compressed air on any photo equipment. I clean lenses using this

stuff, in this order (depending on how dirty it got): (1) blower

brush (2) micro cloth (3) breath on lens then micro cloth (4) lens

cleaning fluid (residual oil remover or formular MC) and micro cloth.

 

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Use only the brush on the focusing screen. Don't touch the mirror!

[steve_dunn3]

I don't use compressed air on my lenses, though I don't know if it's

supposed to be bad or not. I'd agree with the suggestions of the

previous response.

 

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Like the first response said, the fluorite element is not exposed -

every lens model that has a fluorite element as the first real element

has a piece of protective glass in front of it. Unless you're

disassembling the lens to clean it (not recommended unless you know

what you're doing :-), you'll never come in contact with the fluorite.

[isaac sibson]

<div>Since, as far as I'm aware, the lens in question is the 70-200

F4L, the fluorite element is the third element. Both the front and

rear elements of this lens are standard glass (see this block

diagram <a href="http://www.canon.com/camera-

museum/camera/lens/ef/bd/ef_70~200_4l_usm_bd.gif">EF 70-200 F4L USM

</a>, but they are coated and should be treated carefully. Certainly

a lens should not need cleaning for several months after the last

clean (or after it is bought), unless it has been used in some

particularly "dirty" conditions.

 

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For this reason, I like to keep a filter on the lens, since it is a

simpler job to take the filter off the lens and clean it than to

clean the lens itself, with rather lower stakes (I'd rather scratch

a £40 filter and replace it than a £600 lens). Of course, with

quality glass like the 70-200 F4L, you must not skimp on the filter.

[david_oneill]

I just purchased a 70-200f4L and I noticed your comment on not

skimping on the filter. What would you recommend as a filter for this

lense?

[preston_merchant]

B+W Filters are generally regarded as superior:

 

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http://www.schneideroptics.com/filters/filters_for_still_photography/

 

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I use them and am happy with them.