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I just bought a Canon 750D. The picture has too much noise. The detail/shine of the diamond is not really showing. I am also using a tripod and timer.

The lens is the EF-S 18-55mm ƒ/3.5-5.6 IS STM. The picture was taken at 55mm, for 1/20 sec at ƒ/22 and ISO 200. I used manual focus, with center-weighted metering.

DATA

  • I do not understand what of the images is at 100%, no resampling. The round or the one in the left? – Rafael Apr 30 '17 at 1:47
  • @Rafael , Left is the raw and the right is the edited. The detail of the diamond is not really showing. – Margz Apr 30 '17 at 5:38
  • F/22 at 55mm is the worst setting for sharpness for that lens. Look it up on DXOMark.com. It's about 3-mpix (perceived megapixels). – Mike Dixon Apr 30 '17 at 11:15
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I see very little to no noise in the example provided with the question. What is evident from looking at the example is blurring that can be attributed to the effects of diffraction by using an aperture of f/22.

For more about diffraction, please see:
What is a "diffraction limit"?
Do smaller apertures provide more depth of field past the diffraction limit, even if peak sharpness suffers?
How does sensor size impact depth of field and diffraction for macro photography?

For more about digital image noise, please see:
What is noise in a digital photograph?
What is "ISO" on a digital camera?
Why photos taken with flash appear to have less noise?
What's the best way to deal with hot/stuck pixels in long exposure night photographs?
Should I turn off in-camera long exposure noise reduction when shooting for image stacking?

For more about stacking images to increase depth of field, please see:
What are the best practices for DOF stacking?
What is a focusing rail?
Why would a photographer do focus stacking?
Can software auto-detect image focus?

For more about how to maximize depth of field (DoF) to get an entire object in focus, please see:

How can I get crisp, clear product photography with everything in focus?
How best to shoot "packaged goods"?
How to take a photo of a close-up object without focus stacking?
How do I get more in focus when aperture is already quite small?
How can I capture product photography with the entire product in focus?
How can I get more of this macro photo in focus?
How to have a sharp product image?

For more about tying it all together, please see:
How could I achieve stock quality sharpness?

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Noise will improve if you go from ISO 200 to ISO 100.

f22 is a bit too narrow aperture with risk of diffraction artefacts. Consider opening the lens a bit, and go for the depth of field via image stacking instead.

The 18-55mm zoom lens is not really a good macro performer; consider a fixed lens such as the 100mm macro or the plastic fantastic f1.8 50mm with an extension ring. Or and old manual focus M42 50mm (Tessar or Industar, which is the same thing, come to mind) with an M42 extension ring, they come very cheap.

With shooting shiny objects be careful with lighting, it can be real pain...

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I think there are two options:

  • Shoot ,as Jindra Lacko allready noted, with ISO 100. The lower the sensitivity is the higher SNR (signal-to-noise ratio) is as well.

  • Shoot the scene multiple times and blend the images in one. Here you use the randomness of the noise in your advantage - when blending (averaging) random values - noise - they tend to cancel out but the systematic pattern - scene - tends to stay untouched.

  • Consider better fixing, I think the ring moved sligtly.

  • Stacking images will average out photon shot noise that is random. It will do nothing for pattern read noise that is constant from one shot to the next. The best way to deal with read noise is to take a dark frame periodically during the shoot and use the dark frame subtraction feature included with most image stacking applications. – Michael C Apr 29 '17 at 16:00
  • @MichaelClark How can one achieve pattern noise? And to your suggestion, did you mean to take pohotose in sequence ring1-black board1-ring2-... and in postprocessing substract the BB1 from ring1 etc and stack results? – Crowley Apr 29 '17 at 17:18
  • One need not take a corresponding dark frame for every regular frame. For a short session just one at the end will suffice. Dark frames, their uses, how to use them, and pattern noise have all been covered well in questions here. – Michael C Apr 29 '17 at 21:42

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