How many words is suitable to use at a title photograph?

[juanmanolo]

Hi!

I don't have any idea about how many keywords is appropiate to include at a photograph's title, alternative text and description and how much does it affect to SEO. Could you help me?

Thanks.

[scanlin]

Best practices for on-page SEO say that the alt text for an IMG tag should be equal to the keyphrase that the page is optimized for. So if you are optimizing a page for 'blue widgets' then having an IMG with alt text = 'blue widgets' would be good. You may also want to name the image file blue-widgets.jpg (or blue-widgets.png or .gif). It's one of several on-page signals you can send Google that this page is all about blue widgets.