A cryogen free cooling apparatus comprising: a vacuum chamber; a first heat radiation shield surrounding a working region and located in the vacuum chamber; a cryofree cooling system having a first cooling stage coupled to the first heat radiation shield and a second cooling stage, colder than the first cooling stage; aligned apertures (52, 56) in the first heat radiation shield and the vacuum chamber wall; sample loading apparatus having one or more elongate probes and a sample holding device attached to the one or more elongate probes, the one or more elongate probes for inserting the sample holding device through the aligned apertures (52, 56) to the working region; and one or more thermal connectors, whereby the sample holding device is releasably coupled for heat conduction via said thermal connector(s) to the first heat radiation shield so as to pre-cool a sample on or in the sample holding device before the sample holding device is inserted into the working region; characterised by a second heat radiation shield located inside the first radiation shield and surrounding the working region, the second heat radiation shield coupled to the second cooling stage and having an aperture aligned with the apertures (52, 56) of the first heat radiation shield and the vacuum chamber wall so as to allow the sample holding device to pass therethrough, whereby the sample holding device is releasably coupled for heat conduction via said thermal connector(s) to the second heat radiation shield so as to further pre-cool a sample on or in the sample holding device before the sample holding device is inserted into the working region. a vacuum chamber; a first heat radiation shield surrounding a working region and located in the vacuum chamber; a cryofree cooling system having a first cooling stage coupled to the first heat radiation shield and a second cooling stage, colder than the first cooling stage; aligned apertures (52, 56) in the first heat radiation shield and the vacuum chamber wall; sample loading apparatus having one or more elongate probes and a sample holding device attached to the one or more elongate probes, the one or more elongate probes for inserting the sample holding device through the aligned apertures (52, 56) to the working region; and one or more thermal connectors, whereby the sample holding device is releasably coupled for heat conduction via said thermal connector(s) to the first heat radiation shield so as to pre-cool a sample on or in the sample holding device before the sample holding device is inserted into the working region; characterised by a second heat radiation shield located inside the first radiation shield and surrounding the working region, the second heat radiation shield coupled to the second cooling stage and having an aperture aligned with the apertures (52, 56) of the first heat radiation shield and the vacuum chamber wall so as to allow the sample holding device to pass therethrough, whereby the sample holding device is releasably coupled for heat conduction via said thermal connector(s) to the second heat radiation shield so as to further pre-cool a sample on or in the sample holding device before the sample holding device is inserted into the working region.