A series of regular blog posts displaying images from “British Cavalry Uniforms of the 19th Century”; a set of trade cards issued by Badshah Tea Co. of London in 1963.
#24: The 4th Light Dragoons
“The officer depicted on this card is of the 4th Light Dragoons as they were in 1822, shortly after regiment was converted from Heavy Dragoons. [A previous] card in this series shows the uniform worn during the Peninsular War.”

Sites of interest about the 4th Light Dragoons:
The ‘previous card’ referred to above, The 4th Queen’s Own Dragoons, was posted back in March 2017. Another card depicting a later incarnation of the 4th Light Dragoons was posted back in October 2016, just prior to it’s conversion to Hussars in 1860.
National Army Museum page on the 4th Queen’s Own Hussars (Light Dragoons).
The old museum of the Queen’s Own Hussars is due for closure in 2017 but a project for the replacement (in a merger with the Queen’s Royal Irish Hussars museum) is underway. The new Warwick-based Queen’s Royal Hussars museum is currently fund-raising and donations are being accepted through this new website.
A good summary of the history of the regiment can be found here on a family history website, concentrating on the period 1824-1856 during which time an ancestor served.
Roger Fenton photograph of officers of the 4th Light Dragoons during the Crimean War.