Fungus in rear elements Sigma Mini Wide 28mm f2.8

ColinM · 10-21-2022, 09:42 AM

Hi all,

New to these forums, but noticed a few people managed to disassemble a Sigma Mini-Wide 28mm f2.8.

Just wondering where to find how to as I have just got one off eBay with some fungus on the inner rear elements.

I have dabbled with other lenses, getting mixed successes.

Any help appreciated.

Thanks

**marcusBMG** · 10-21-2022, 10:48 AM

Hi, welcome.

see

sigma 28mm 2.8 mini wide II disassemble for problems - PentaxForums.com

ColinM · 10-22-2022, 12:37 AM

Thanks marcusBMG, that will help me get the rear off the lens. Is there anything about getting the lenses themselves out and getting access to clean them?
ColinM

---------- Post added 10-22-22 at 01:22 AM ----------

Hi,

I have found this guide elsewhere on the Internet to strip down a Mini-Wide II, not sure what the difference is between the one I have which doesn't have the II.

https://www.vintagestories.nl/post/disassembly-sigma-mini-wide-ii-28mm-f2-8

ColinM

**marcusBMG** · 10-22-2022, 02:28 AM

I'm not sure what the difference between the first miniwide and the II are - in general terms they are very similar. I would be surprised if they weren't more or less the same: take off the mount and the rear element housing will unscrew (somehow). Nail varnish remover (acetone) may be useful for softening any thread locker. Then you may need to ease or tap the elements out NB note which way round they go - put it back in back to front and you wil be wondering what on earth has happened to your images. sometimes it is sufficient to just reach in once you have access to the affected side of teh element - bit of tissue on a cocktail stick, lens pen to finish.
I use a drop of mould and mildew remover in meths and a dried out paper lens cleaning tissue - basically anything wit detergent effect will clean the fungus right off and kill it. Then just normal lens cleaning stuff - tissues, blower etc to finish off. With small elements it is even more pertinent to use plastic gloves and avoid getting fingerprints etc on the glass.

10-21-2022, 09:42 AM	#1
ColinM New Member Join Date: Oct 2022 Posts: 2	Fungus in rear elements Sigma Mini Wide 28mm f2.8 Hi all, New to these forums, but noticed a few people managed to disassemble a Sigma Mini-Wide 28mm f2.8. Just wondering where to find how to as I have just got one off eBay with some fungus on the inner rear elements. I have dabbled with other lenses, getting mixed successes. Any help appreciated. Thanks

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
For Sale - Sold: Sigma 28mm Mini-wide II f2.8 (US)	meszidik	Sold Items	2	03-17-2010 11:52 AM
For Sale - Sold: [Worldwide] Sigma mini-wide II 28mm f2.8	causey	Sold Items	5	03-11-2010 07:40 AM
For Sale - Sold: Sigma Mini-Wide II 28mm/f2.8, MF, K-mount, "A" setting, in excellent condition	yb_abq	Sold Items	14	04-25-2009 03:55 PM

10-21-2022, 10:48 AM	#2
marcusBMG Site Supporter Join Date: Nov 2012 Location: North Wales Photos: Gallery \| Albums Posts: 2,869	Hi, welcome. see sigma 28mm 2.8 mini wide II disassemble for problems - PentaxForums.com

10-22-2022, 12:37 AM	#3
ColinM New Member Join Date: Oct 2022 Posts: 2 Original Poster	Thanks marcusBMG, that will help me get the rear off the lens. Is there anything about getting the lenses themselves out and getting access to clean them? ColinM ---------- Post added 10-22-22 at 01:22 AM ---------- Hi, I have found this guide elsewhere on the Internet to strip down a Mini-Wide II, not sure what the difference is between the one I have which doesn't have the II. https://www.vintagestories.nl/post/disassembly-sigma-mini-wide-ii-28mm-f2-8 ColinM

10-22-2022, 02:28 AM	#4
marcusBMG Site Supporter Join Date: Nov 2012 Location: North Wales Photos: Gallery \| Albums Posts: 2,869	I'm not sure what the difference between the first miniwide and the II are - in general terms they are very similar. I would be surprised if they weren't more or less the same: take off the mount and the rear element housing will unscrew (somehow). Nail varnish remover (acetone) may be useful for softening any thread locker. Then you may need to ease or tap the elements out NB note which way round they go - put it back in back to front and you wil be wondering what on earth has happened to your images. sometimes it is sufficient to just reach in once you have access to the affected side of teh element - bit of tissue on a cocktail stick, lens pen to finish. I use a drop of mould and mildew remover in meths and a dried out paper lens cleaning tissue - basically anything wit detergent effect will clean the fungus right off and kill it. Then just normal lens cleaning stuff - tissues, blower etc to finish off. With small elements it is even more pertinent to use plastic gloves and avoid getting fingerprints etc on the glass.