Start with a measured older example
Ztijl records a sold black Fog & Mørup Semi with a 47 cm diameter and a stated height of 26 cm. It describes a white interior and says an electrician checked the wiring. Those are details of that offered lamp; the electrical statement is not a report on another example.[1]
GUBI’s current Semi reference names Claus Bonderup and Torsten Thorup and dates the design to 1968. Its current sizes are a separate product range. Do not use a contemporary size chart as a complete catalogue of earlier Fog & Mørup production or copy an old seller’s conflicting design date without qualification.[2]
Ask for the widest shade diameter, shade height, total suspension length and photographs of any labels. Keep design attribution, producer and the age of the individual lamp as separate entries in your notes. A shape match alone cannot fill them all.
A thin edge makes damage easy to overlook
Request evenly lit views from above, below and across the rim. A wide shade can look oval in perspective even when it is round, so ask for a direct view or measurements across more than one direction before diagnosing distortion from a photograph.
Look for disclosed dents, a distorted edge, repairs and changes to the interior coating. Do not assume a dent can be pushed out without affecting the surface. Ask a suitable lighting restorer about the result and cost before pricing the lamp as an easy cosmetic project.
| Part | Question to resolve |
|---|---|
| Outer shade and rim | Dents, distortion, coating loss and repairs. |
| Interior | Finish, discoloration and any repainting. |
| Holder and suspension | Complete, compatible components and replaced parts. |
| Cable and electrical assembly | Assessment and work needed for intended installation. |
A fresh woven cable is a visible change, not evidence that the complete light has been assessed. Ask what work was done, by whom, and what documentation accompanies it.
Try the diameter at full size
Cut a paper circle matching the offered shade diameter and compare it with the table. A 47 cm circle over a 100 cm-wide top leaves 26.5 cm of tabletop on each side when centred in plan. That illustrative calculation describes the footprint only; it is not a recommended hanging height or a prediction of the light spread.
View the proposed size from the doorway and from seated positions. Include the shade’s depth and where its lower rim would appear in your sightline. If the table extends, decide which configuration the light should centre on and whether the other arrangement remains comfortable.
Have the installer consider suspension, ceiling support, suitable lamp specification and the intended position. A paper mock-up is useful for scale; electrical suitability and the final light effect need the actual complete fixture and appropriate professional advice.
Buy the lamp, the work and the journey together
Ask the seller to list the components supplied and identify any replacements. Confirm whether the ceiling canopy and intended suspension fittings are included and suitable for the planned installation. Similar-looking parts are not automatically compatible.
For shipping, ask how the broad rim will be protected without pressure that can distort it. Include necessary restoration, electrical work and installation in the total cost. A more expensive complete example may make better sense than an inexpensive shade with an uncertain assembly.
A useful enquiry
Please confirm the shade dimensions, show the rim and interior directly, list replaced and missing components, and provide the scope of any electrical work. I plan to install it above a ___ cm table.
Choose the Semi whose scale and complete condition you understand. Its sweeping outline is the attraction; the details make it a light you can enjoy using.