Is there a way to eliminate this conversion artifact?

[geldo]

It is the curved top of a microwave oven out of focus against a white wall.
Thank you.
(100% crop)

[Morgan_Hardwood]

Share your raw + PP3 using https://filebin.net/

[shreedhar (Shreedhar Inamdar)]

It looks like Demosaicing artifact. Have a look at

Diagonal interpolation correction artifacts with AMaZE Demosaicing

Hi everyone, I am new here and was referred by Sandy McGuffog from the thread I posted over at the luminous-landscape forums. In that thread I describe in great detail my observations about how different demosaicing algorithms render detail and the issues I observe with each. To summarise: Overall I find AMaZE to give me the best quality, but it is plagued with artifacts that appear like 45-degree diagonal ‘ringing’, and it was Sandy that turned me on to the term ‘diagonal interpolation correct…

[geldo]

here’s the raw file
https://filebin.net/t23vwo0k4f53ng1t

[heckflosse (Ingo Weyrich)]

These are not conversion artifacts. They are already visible without demosaic:

[Elle (Elle Stone)]

Hmm, that uninterpolated (and interpolated) “artifact” looks somewhat familiar. I have an old manual focus Distagon 2.8/28mm lens that produced a similar artifact when photographing sharply defined diagonal lines (in particular a test shot that included some diagonally-placed color post-it notes) when used with a Canon 400d digital camera, which had an 8MB sensor.

As best I could determine by perusing the internet at the time (perhaps in 2008), the problem might have been that the lens was “outresolving the sensor”. But I have no idea whether this really was the issue. And I haven’t photographed a similar sharp diagonal line with this same lens on my Sony A7, to see what happens with a 24MB sensor. And given all the shenanigans Sony A7 plays with their asinine (am I allowed to use this language on pixls.us?) lossy-compressed raw files, I don’t think such tests have much validity for the Sony A7.

[geldo]

Well, it is with a discreet dose of shame that I just discovered what the top of the microwave really looks like. Thank you for your answers, I am sure I can do much better than this

Thank you all!

[afre (Alan)]

Ha ha, it is a feature!