How to understand ISO in cameras
ISO controls how sensitive the camera’s sensor is to light. By increasing the sensor sensitivity you are able to shoot in darker conditions without a flash. Look for cameras that offer ISO 1600 or higher. Some cameras can shoot as high as ISO 25,000 – 102,000. Now, there is a trade-off to using a high ISO setting. Higher ISOs usually mean more noise (colored speckles) and grainier images.
Low ISO: ISO 25,50, 100.
Good for full sun, brighter situation.
Medium ISO: ISO 200, 400, 800.
Good for during the day: dull overcast sky or full open shade. Indoors: a well-lit situation or flash use.
High ISO: ISO 1000, 1600, 3200, 6400
Good for a darker situation, lowlight indoors or outdoors, no flash use.
Tech notes: Help maximize the available light.
Very High ISO: ISO 12500, 54000
Good for hand holding the camera in very low light.
Tech notes: use fast shutter speed to avoid blur.
It's important to use a tripod, to minimise the ISO of high ISO, to have crisper and clearer images.
Here a gallery of product photography, keeping a ISO of 100, to keep all the details clear and crisp.