How to maybe remove some Fungus in Sigma DG 120-400mm 1:4.5-5.6 APO HSM

There was some Fungus inside the front lens group and the back lens group in this Sigma DG 120-400mm 1:4.5-5.6 APO HSM. But it was actually "easy" to remove with Hydrogen Peroxid 3% on a "PEC-PAD" lens wipes.

I first try with Isopropylalcohol 99% but nothing happen, then I try with lighter fluid, and the same happen, it will the Fungus was still there.

So the best solution to remove Fungus is still in my opinion Hydrogen Peroxid 3%.

I sooner found out that it was not nessasary to remove the whole front ring with the lens elements, but I should only have unscrew the front retaining ring and in that way come into the lens elements.

Take good care when working with the back lens group, because of the thin flex cables.

Here are some link's to different repair tool's:

Japan Hobby Tool rubber cone:



18 different size rubber repair tool's:



You can also buy this set.

Lens Repair Set with pointed, flat, half flat tips:

JIS cross head screw driver's:

Or this set, that is the set I use:

Lens cleaning wipes (PEC-PAD):

Thin Cotton Buds x 200 you can buy them here:

DSLRKIT Pro Lens Vise Tool Repair Filter Ring Ajustment Steel 27mm to 130mm:

Japan Hobby Tool Helical Grease Made in Japan:

Loctite 222 50ml Threadlocker

[taurus]

Thank you for the encouragement. I need to get some more tools before i start the job. 👍

[rahandulcaspatal]

Muy buen trabajo amigo estaría interesante saber cómo acceder a las lentes interiores

[Madbeef]

Great video. Suddenly the task doesn't seem that daunting.

[zivamariediva]

Very very helpful. Now I will have a go. Thank you so much

[celblau]

Excelente video Maestro, se agradece siempre su enseñanza!, saludos cordiales!

[Woodyjims-shack]

Thanks I just fixed my loose 50-500 with the help of your video. Going after front element fungus next 👍 thank you 😁

[horsetom]

Excellent video, well explained. Keep up the good work 👍

[martinmuldoon]

Brilliant information, I will prepare a clean room, wash well plus wear hair net etc, now I'm motivated to give this a go on my sigma 70mm to 200mm lens.

[robph]

I would think the lens element can be put back at any position radially. (Only the convex/concave sides are important). But you even mark the radial position with the dot. But you know this business more than any body.

[yktube]

Among so many other things, never EVER provide direct pressure from your fingers ! - Instead turn your sterile cleaning material into a little puff pillow. This assures that you're not applying too much pressure DOWN onto the coatings - What if a tiny particle is embedded in the tissue or still laying on top of the lens element? This is always a possibility unless you're in a 'Clean Room'. - Finally, you must always utilize a self standing High Intensity Lamp (brilliant LED also works) to continuously inspect every step of the re-install of elements & groups (he applied Loctite & never once inspected the optical path in this manner !). BTW : I've been a camera tech for over 35 years...

[christinenash]

Hi can you tell me how to get to the inner lens thank you for great video

[worroSfOretsevraH]

Hi.
Can you please do a fungus removal video on binoculars? Thanks.
(and maybe teach us how to align it afterwards without professional tools)

[priyasad]

Thank you for sharing good video and very helpful information

[yermanoh]

i just took my sigma 70 200 2.8 out of my bag for the first time in almost 2 years ....there's a nice big blotch of fungus on the front element and a small bit on the edge of the second, oh well i might have to try this, , , doesnt look to scary

[tomc]

Hi Kenneth; Great video as always. Would the cleaning of the lens also prevent future fungus attacks?

[bartwaggoner]

Still watching... but where was this lens stored to get fungus at such an early age?

[il-ganna]

I used this method on an old Sigma 18-200 DC. After managing to unscrew the ring from the back lens group - I couldn't get the lens out to clean the fungus in the end because they seem to also be held together by 3 microscopic screws...Any tips?
Either way this was very helpful to make sure nothing broke in the process, thanks!

[aamirkhan-onus]

I have sigma 120-400mm. Middle glass have fungus..how to open?...plz suggest...thanx

[bartwaggoner]

Do you prefer lighter fluid over isopropyl for cleaning regular dirt/oils from the lens elements?

[bearcub]

Your repair videos are awesome, thanks for sharing. I have been looking for the rubber tools but can't find them do you have a link somewhere?