Canon has a very good article on the upcoming eclipse discussing a lot of tips and tricks. The article ends with the following:
SAFETY FIRST: Never look at the sun without accredited and approved solar filtration over your eyes. Permanent, irreversible eye damage and/or blindness can result in seconds. Never point your camera into the sun without an approved solar filter over your camera lens(es). Not using a solar filter at eclipse magnifications will ruin your camera in seconds. Never improvise, modify or use general photography neutral density filters.
here is the link:
http://learn.usa.canon.com/resources/articles/2017/solar-eclipse/photographic-exposure-solar-eclipse.shtml?categoryId=12
If you want to reply, then
register here. Registration is free and your account is created instantly, so you can post right away.