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tokens: of J H K photometry of the entire 3C 294 system. Notes. To derive the magnitudes from Steinbring et al. (2002) , the fluxes from components a, b, and c have been summed. Photometry of individual components have been derived by Quirrenbach et al. (2001) and Steinbring et al. (2002) . A comparison to our data is shown in Table 5 . The difference between the Quirrenbach et al. (2001) and Steinbring et al. (2002) data is large, approximately two magnitudes, while our measurements are somewhere in between. Again, the size of the aperture used is not given for either the Keck-data or CFHT-data. Table 5. Comparison of HK photometry of components a, b, and c of the 3C 294 system. Notes. The K images have been taken through different filters (see Table 4 ) but the differences are small and did not affect the large differences seen between the individual measurements. We also created J − H , H − K s , and J − K s color maps for 3C 294 to search for any evidence of spatially-dependent extinction in the three components. No obvious feature was detected. 3.2. Optical spectra of the <ext-link ext-link-type="aoi">3C 294</ext-link> system The one-dimensional and two-dimensional spectra of the 3C 294 system are shown in Fig. 4 . Despite our 2 h integration time, we do not detect any obvious continuum. When rebinning the spectra in spectral and spatial direction by a factor of five, a hint of continuum can be glimpsed in the red channel. However, with this rebinning, the potential continuum of components a, b, and c would overlap, preventing us from distinguishing between the two components (see below). We detected the Ly α λ 1215 Å, C IV λ 1550 Å, He II λ 1640 Å, and C III] λ 1907/1909 Å lines in the blue channel. The C III] line is blue-shifted with respect to the other lines. This is not unusual in AGN (e.g., Barrows et al. 2012 ) and may be a result of the increased intensity of the transition at λ 1907 Å relative to the one at λ 1909 Å at low densities ( Ferland 1981 ). Only one emission line at λ 6749.4 Å can be detected in the red channel. It is faintly present in the individual spectra from both MODS instruments and is not an artifact of the data reduction. Under the assumption that it originates from the same source as the emission lines in the blue channel, we identify this line with the Ne [IV] doublet λ 2424/2426 Å at z = 1.783. Similarly to our C III] λ 1907/1909 Å line in the blue channel we would not be able to separate the double lines individually given an instrumental resolution of ∼5 Å. If the identification is correct, we may even associate the very faint emission at λ ∼ 6485 Å with C II] λ 2326 Å at z ∼ 1.788. The position of this line coincides with a forest of night-sky emission lines, however, so this detection is tentative. To our surprise, we do not detect Mg II λ 2798 Å in our spectra, which we would expect at λ ∼ 7790 Å. However, Mg II is relatively weak in radio galaxies ( McCarthy 1993 ) and line ratios can vary strongly in