If a picture you are about to post looks blurry to you, or has absolutely no detail because it is too dark, too washed out, etc - It is going to look the same to us. A dark, featureless, blurry copper disk is going to look just like a dark, featureless, blurry copper disk to us.
Posting a blurry mess and asking us to ID it is generally pointless.
Zoom and Crop: Please crop your pictures. The only thing of interest in the picture should be the item in question. Posting a picture with a tiny object in the center with 25 square feet of your kitchen table in the background is unproductive.
Rotate: Posting pictured sideways or upside down are difficult to look at. Of course, the exception is when you have no idea which side it top, bottom, left or right. If it is a coin and it has a someone's head of the face of the coin, it should be obvious.
Tablets and Phones all have software that can focus, resize, zoom, crop, and rotate. Using the excuse that you don't know how to use the software is just plain lazy. If you want us to help you out, you need to help us out too.
When in doubt of a picture's quality, show it to someone before you post. If they can't make it out, retake, or ask them to take it.