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Tutoriels de réparation pour la gamme Minolta qui a désormais interrompu sa production.

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Is this look like a crack or a deep scratch? *Minolta 80-200 f4.5 kit*

I asked this back in 2018, but didn't have the means to get a proper balanced photo of the defect. I know I could edit the 2018 post, but it's 5 years old and I had bad photos.

I have had this lens for quite a few years, as well as a mint 50mm 1:7, and both are "common" as the 50mm was often a kit lens, or a popular add-on at the time it was new. It has no issues and I got a chance to take it out 5 years later; it is freaking good. However, I took this one out with me as well to better inspect it (as well as a backup Sigma with similar range; 28-200 f1:38-5.6 UC) just in case; glad I did, as it was not pretty.

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I'm pretty much just about 100% confident this is a crack, which is why I reverted back to the Sigma but was also prepared with a spare Quantaray* which doesn't go out as far, but is made by Sigma. Is this look usable, or should I dump it in a parts lens lot?

*PLEASE DO NOT GIVE ME ANY CRAP about this based on the name like dedicated forums. I know about how quick some people are to rip on someone for having a Quantaray despite most being made by Sigma and not Tiffen since it's a Ritz special. Mine look like Sigmas.

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@nick - Is the Yellow/Orange spot a light refection? If it is then I would say its most likely a scratch. Optical glass is on the softer side and there are metal coatings to prevent flares and often on the outer surface a harder Quartz or Sapphire coating is deposited.

I had a scratch on a very expensive lens and as its no longer made replacing it was not in the cards. I tried windshield epoxy using a vacuum to fill the gash being careful not to over do it as you can't polish it down without damaging the coatings around it which would make more of a mess!

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@danj It is a reflection but I had to hold off he lens at a weird angle to show where it is. Sad to say, but the lens design basically makes the filler strategy borderline impossible.

Guess I should consider myself lucky it happened on a throwaway lens I can throw away and not care.

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@nick looks like a crack but looks can be deceiving. I suggest a crack detection with dye penetrant testing (PT). Get some fluorescein and wipe in on the lend. Let is sit for a short time (15-30sec) then simply wipe it off. Now use a UV light and shine it on your lens. If it’s a scratch you can wipe it off, it its a crack the dye will have penetrated into the crack and continue to shine under the UV light.

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I felt it with my fingernail once, but only at the right angle. I can feel one of the marks with my nail but not the other. The reason I mentioned just getting rid of it is not to "waste it", necessarily. The hard truth is this is a $15-20 lens all day due to the kit lens nature. The reason I'll wait and see to get an idea before I decide if I want to sell it (for parts, I can't confidently sell this one on as good due to it) if it's bad is SOMETIMES the best bodies like the 700/800si come with cheap lenses I just do not care about which were for protection. I'd just sell it with a few other bums for parts so someone can repair it and use it.

I might run one photo through it to see if the damage affects the photos. If it does, then yeah keep the 50 and not this. I hate to waste a frame of Fuji 400 on such a cheap lens, but I have to :(. If it's noticeable, yeah I won't feel as bad about the test.

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Nick sera éternellement reconnaissant.
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