The subject of image warming came up recently in the forum with someone asking,
"What does it mean" and "How is it done".
Adding warmth to a photograph can be achieved with most image editing programmes.
Paint Shop Pro X for instance offers several different tools 1 of which looks like this....

You can also fit various filters to your lens and this is explained below

A colour temperature chart gives you some idea of what sort of result
to expect depending upon your white balance setting and the weather..

A very good article which covers the subject nicely is reproduced below.
The author is Jim Altengarten

And lastly Here is a link to an extensive article from the Apogee Photo Magazine
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