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File format must be JPG, JPEG, or PNG.
Color mode must be RGB.
Images should be 2,000 pixels or larger on the longest side.
Resolution should be at least 300 dpiThe images must have good visual image quality:
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54. Images should be free of vignettes, glare, and other kinds of light effects:
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65. Images should have a fully repeatable or a completed pattern (if put together, they look seamless):
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76. Images should be free of image noise:
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87. Images cannot be posterized:
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98. It’s desirable to avoid moiré patterns:
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109. Images must not have distorted perspective:
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