I would be very cautious about this idea. The cutting of the wire will
work harden it and copper will scratch fluorite. I suppose you could
soften it again by flaming though. If any scraping is in order I would
definitely use a dissecting microscope to avoid lens damage. Pushing a
wadded lens tissue with liquid lubricant and forceps should a first
option I think.
my 2c
Regrds Mark Cannell
Barry O'Brien wrote:
> A factory-trained service technician recommended to me that if a lens
> needed scraping in any way then the preferred implement was copper
> wire. If you cut this with ordinary side-cutters there is a bevelled
> edge produced.
>
> Barry O'Brien
>
> At 12:04 a.m. 02/04/2009, you wrote:
>> Unrelated really but, our biggest problems is undergraduates on the
>> teaching lab microscopes getting DPX on the lenses.
>> While they are always told how to avoid this, drop the stage before
>> swinging a high magnification lens into place, in the excitement a
>> fair number forget this after having tipped the contents of the DPX
>> bottle onto the slide and floated a cover slip on the top.
>>
>> I have been told that chloroform should get this off, however this
>> has not been particularly successful when the DPX has dried on.
>>
>> Of course I do get the DPX off but I hesitate to mention my technique.
>>
>> Anyone come across a tried and tested method that doesn't involve
>> careful application of a razor blade?
>>
>> Leigh Silvester
>>
>> ------------------------------------------------------------------------
>> From: Confocal Microscopy List [
>> mailto:[log in to unmask]] On Behalf Of Guy Cox
>> Sent: 01 April 2009 11:00
>> To: [log in to unmask]
>> Subject: Re: Cleaning lens.
>>
>> When I first learnt about microscopes (a very long time ago) I
>> was taught that while dry objectives often had their front
>> element mounted with some adhesive, oil immersion objectives
>> didn't - the element was held by a screw ring. Hence it was safe
>> to clean them with solvent - we usually used xylene because that
>> was handy - it was also used in mounting specimens (with canada
>> balsam). Of course this didn't offer any solution to the clumsy
>> clot who gets oil on the x40. But that wasn't actually quite so
>> common then because oil immersion lenses were longer - ie not
>> parfocal - so if someone swung the turret round the dry lenses
>> would clear the oil. On the other hand this didn't make using oil
>> lenses too easy - and they didn't have spring noses then either.
>>
>> Nowadays I'd have thought that if any adhesive is used it would
>> be epoxy which is pretty much immune to solvents.
>>
>>
>> Guy
>>
>>
>> Optical Imaging Techniques in Cell Biology
>> by Guy Cox CRC Press / Taylor & Francis
>> http://www.guycox.com/optical.htm
>> ______________________________________________
>> Associate Professor Guy Cox, MA, DPhil(Oxon)
>> Electron Microscope Unit, Madsen Building F09,
>> University of Sydney, NSW 2006
>> ______________________________________________
>> Phone +61 2 9351 3176 Fax +61 2 9351 7682
>> Mobile 0413 281 861
>> ______________________________________________
>> http://www.guycox.net <http://www.guycox.net/>
>>
>>
>> ------------------------------------------------------------------------
>> From: Confocal Microscopy List [
>> mailto:[log in to unmask]] On Behalf Of Keith Morris
>> Sent: Wednesday, 1 April 2009 6:47 PM
>> To: [log in to unmask]
>> Subject: FW: Cleaning lens.
>>
>> I think Zeiss’s comment that repeated use of ethanol will damage
>> Zeiss’s lens cement was just that – use it a few times a day and
>> the Zeiss objective will probably fail in 6 months or so [and
>> this might be the case for many solvents, ethanol is simply one
>> more readily at hand*]. Use ethanol every month or so and chances
>> are the objective will last a lot longer [and fail for another
>> reason]. Use ethanol on a very elderly microscope where the
>> lenses are mounted in say gum resin though and you will destroy
>> the objective pretty much instantly [or at least get a nasty
>> smear of gum resin all over the clear bit] - hence some people’s
>> historical aversion is justified. I did mention to a Zeiss rep
>> why did he just use 70% ethanol on our new 100x zillion NA TIRF
>> objective when Zeiss say that repeated use will damage the
>> objective, he said, well repeated use will damage the objective,
>> but once or twice won’t matter [and then I thought ‘well I
>> suppose it’s not actually his £8,000 objective’]. Other
>> manufacturer’s actually recommend ethanol, e.g. Olympus. However
>> immersion oil doesn’t dissolve in ethanol that well, hence
>> another reason for the recommended use of other solvents, e.g.
>> Petroleum ether - see
>> http://instrument-support.nikonusa.com/app/answers/detail/a_id/10379
>>
>> *from the micro/primer site: "In the past, solvents have been
>> routinely employed for nearly any cleaning task in microscopy,
>> and particularly for removal of immersion oil. Potential problems
>> associated with solvent cleaning are sufficiently serious that
>> the best current approach in cleaning the microscope is to use
>> solvents only when absolutely necessary, essentially as a last
>> resort rather than a first step. The issue of the use of solvents
>> is further complicated and confused by contradictory
>> recommendations in the scientific literature, as well as by
>> differences in manufacturers' technical publications. Although
>> alcohol and xylene are widely recommended as lens cleaning
>> solvents, they are also named as being harmful to both the
>> mechanical and optical components of many microscopes. Because of
>> the variation in solvent recommendations, and the likelihood that
>> some of the materials used in the instrument components are not
>> known to the user, it is prudent to restrict use of any solvent
>> to an absolute minimum.”
>>
>> i.e. have a look at:
>> http://micro.magnet.fsu.edu/primer/anatomy/cleaning.html
>>
>> Most of this discussion of solvents only applies to immersion oil
>> objectives, where the oil isn’t miscible in water. Our inverted
>> microscopes with all air objectives are rarely cleaned, otherwise
>> it’s just a blow with a puffer. On microscopes where oil and air
>> co-exist it’s often immersion oil contamination of the air
>> objective that’s the problem, so it’s solvents again. In the days
>> when only my group operated the microscopes, with all our oil
>> immersion free upright microscopes the objectives almost never
>> needed cleaning.
>>
>> For other spillages such as culture medium [inverted microscope
>> again] some solvents will probably fix biological muck onto the
>> lens, and there’s the salts content, so the use of water based
>> cleaners has been suggested [e.g. even breathing on the lens and
>> then lens tissue, using optical/glass cleaning solutions]. Water
>> drying onto the lens is a disaster though. Some even recommend
>> things like breaking polystyrene foam [to get a clean surface]
>> and gently rubbing the [oil free] lens with that. Or there’s
>> Sparkle - whatever that is, here in the UK it was a silicon based
>> furniture polish [yuk] not a commercial window glass cleaner.
>> That’s the problem with industrial cleaners, who knows what’s in
>> them or whether the constituents have been modified – you could
>> try it on an inconspicuous area of the objective lens first, I
>> suppose. Presumably optical lens cleaners are glass friendly
>> though, and many use glass cleaning products with no reported
>> problems. All the links in the previous posts [below] give loads
>> of ideas for cleaning objectives [when necessary].
>>
>>
>>
>> http://www.zeiss.com/C1256F8500454979/0/F9B766E00E70F4C4C1256F8D0054FFF8/$file/thecleanmicroscope.pdf
>>
>>
>>
>> http://books.google.com/books?id=Dhn2KispfdQC&pg=PA51&lpg=PA51&dq=petroleum+spirit+cleaning+objectives&source=bl&ots=JxlHfCVuF5&sig=NTJt3Ol66sgsB8gluF1eKpeXLCc&hl=en&ei=DfvRSdGpI5WrjAflkvjlBg&sa=X&oi=book_result&resnum=1&ct=result
>> <http://books.google.com/books?id=Dhn2KispfdQC&pg=PA51&lpg=PA51&dq=petroleum+spirit+cleaning+objectives&source=bl&ots=JxlHfCVuF5&sig=NTJt3Ol66sgsB8gluF1eKpeXLCc&hl=en&ei=DfvRSdGpI5WrjAflkvjlBg&sa=X&oi=book_result&resnum=1&ct=result>
>>
>>
>> http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/artfeb04/cdclean.html
>>
>>
>> www.
>> <http://www.olympus.co.uk/microscopy/images/illum_cleaning.pdf>
>> olympus.co.uk/microscopy/images/illum_cleaning.pdf
>> <http://www.olympus.co.uk/microscopy/images/illum_cleaning.pdf>
>> http://www.olympusmicro.com/primer/techniques/fluorescence/troubleshoot.html
>>
>>
>>
>> Keith
>>
>> ---------------------------------------------------------------------------
>> Dr Keith J. Morris,
>> Molecular Cytogenetics and Microscopy Core,
>> Laboratory 00/069 and 00/070,
>> The Wellcome Trust Centre for Human Genetics,
>> Roosevelt Drive,
>> Oxford OX3 7BN,
>> United Kingdom.
>>
>> Telephone: +44 (0)1865 287568
>> Email: [log in to unmask]
>> Web-pages: http://www.well.ox.ac.uk/cytogenetics/
>> ------------------------------------------------------------------------
>> From: Confocal Microscopy List [
>> mailto:[log in to unmask]] On Behalf Of Chris Tully
>> Sent: 30 March 2009 16:40
>> To: [log in to unmask]
>> Subject: Re: Cleaning lens.
>>
>>
>>
>> Dear all,
>>
>> While working for a Leica Microsystems dealer the local field
>> service engineer (factor trained) used a sequence of ethanol and
>> heptane to clean truly dirty lenses. For standard cleaning a lens
>> wipe and Sparkle was his recommendation. But for dried oil or the
>> like he would graduate to cotton swabs and either ethanol then
>> heptane or a 50:50 mix of the two.
>>
>> Chris
>>
>> Chris Tully
>> Microscopy and Image Analysis Expert
>> [log in to unmask] <mailto:[log in to unmask]>
>> 240-888-1021
>> http://www.linkedin.com/in/christully
>>
>> On Mon, Mar 30, 2009 at 10:12 AM, Ian Montgomery <
>> [log in to unmask]
>> <mailto:[log in to unmask]>> wrote:
>>
>> Keith,
>>
>> Methylated spirit that’s what he said, although I still prefer
>> and use ether when necessary.
>>
>> Ian.
>>
>>
>>
>> Dr. Ian Montgomery,
>>
>> Histotechnology,
>>
>> I.B.L.S. Support Unit,
>>
>> Thomson Building,
>>
>> University of Glasgow,
>>
>> Glasgow,
>>
>> G12 8QQ.
>> ------------------------------------------------------------------------
>> From: Confocal Microscopy List [
>> mailto:[log in to unmask]] On Behalf Of Keith Morris
>> Sent: 30 March 2009 14:12
>>
>>
>> To: [log in to unmask]
>> <mailto:[log in to unmask]>
>>
>> Subject: Re: Cleaning lens.
>>
>>
>>
>> Are you sure the Zeiss Engineer didn’t say ‘petroleum spirit’?
>> Methylated spirit is mainly ethanol, and so best avoided - the
>> Axiovert 100 manual says repeated use of 70% ethanol will damage
>> the objectives [but you can use it if you want]. Generally the
>> faster the solvent evaporation from the lens/cement area the
>> better, hence the suggestion of the solvent [pure] diethyl ether
>> by many [and that’s what I use].
>>
>>
>>
>> ‘Zeiss cleaning mixture L’, which the engineer’s now use since
>> diethyl ether has been withdrawn from their kit, is 90% by volume
>> ‘benzoline’ [petroleum ether sometimes called medical alcohol]
>> and 10% ‘isopropanol’ [2-proponal, dimethyl carbinol,
>> 2-hydroxyproparne]. The bottle says ‘Clean the optics by moving
>> in circles, slight pressure should be exerted on optics during
>> cleaning’. Petroleum ether or spirit isn’t the same as the
>> diethyl ether solvent/anaesthetic often used to clean objectives,
>> but apparently it does the job for Zeiss optics.
>>
>>
>>
>> Keith
>>
>> ---------------------------------------------------------------------------
>> Dr Keith J. Morris,
>> Molecular Cytogenetics and Microscopy Core,
>> Laboratory 00/069 and 00/070,
>> The Wellcome Trust Centre for Human Genetics,
>> Roosevelt Drive,
>> Oxford OX3 7BN,
>> United Kingdom.
>>
>> Telephone: +44 (0)1865 287568
>> Email: [log in to unmask] <mailto:[log in to unmask]>
>> Web-pages: http://www.well.ox.ac.uk/cytogenetics/
>> ------------------------------------------------------------------------
>> From: Confocal Microscopy List [
>> mailto:[log in to unmask]] On Behalf Of Ian Montgomery
>> Sent: 30 March 2009 12:28
>> To: [log in to unmask]
>> <mailto:[log in to unmask]>
>> Subject: Cleaning lens.
>>
>>
>>
>> In one of our teaching labs many years ago a student complained
>> they were having a problem with the x100 OI objective and sure
>> enough the image was lousy. I cleaned the objective and slide
>> then re-applied a spot of oil and still the image was lousy. I
>> then asked the student how exactly they had set up the
>> microscope. Shock horror, my world collapsed. They had unscrewed
>> the objective, filled it with oil, screwed it back on then put a
>> drop on the slide. After weeks of trying to clean the objective
>> it went into the trash as beyond economic repair.
>>
>> Cleaning objectives, I use the fluid recommended by the local
>> Zeiss engineer, 90% methylated spirit and 10% isopropanol.
>>
>> Ian.
>>
>>
>>
>> Dr. Ian Montgomery,
>>
>> Histotechnology,
>>
>> I.B.L.S. Support Unit,
>>
>> Thomson Building,
>>
>> University of Glasgow,
>>
>> Glasgow,
>>
>> G12 8QQ.
>>
>>
>>
>>
>>
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>
> Dr Barry O'Brien
> Dept of Biological Sciences,
> University of Waikato
> Private Bag 3105
> HAMILTON
> New Zealand
>
> Fax 0064 7 838 4324
> Phone 0064 7 838 4179
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