I was looking into buying the official Fujifilm macro extension tubes for the GFX yesterday to do some macro photography work for fun, but now I am leaning towards giving 3rd party adapters a try since I can purchase both for less than the price of one Fujifilm adapter. There isn’t a lot of information around about how well they work with the GFX lens line up.
The Viltorx 18mm and 45mm adapters should match the Fujifilm GFX macro extension tub specs below, but Fotodiox has slightly longer extenders at 20mm and 48mm.
Photons to photos also made their own calculations when Fujifilm’s specs went missing, which you can see here or below. Information about extension tubes hasn’t been very easy to find since they are kind of a niche product, but for $100 they could be a lot of fun and help to make your kit more useful.
Of course, we could calculate this out ourselves using the formula below.
An extension tube increases lens magnification by an amount equal to the extension distance divided by the lens focal length. For example, adding a 25 mm extension tube to a 50 mm lens will give a magnification gain of 0.5X. Therefore, if the lens’s original magnification was 0.15X, then the new magnification will be 0.15X+0.5X=0.65X. The closest focusing distance will also decrease to ~210 mm.
Viltrox 18mm DG-GFX Extension Tube: B&H Photo / Amazon
Viltrox 45mm DG-GFX Extension Tube: B&H Photo / Amazon
Fotodiox Pro 20mm Auto Macro Tube for GFX: B&H Photo / Amazon
Fotodiox Pro 48mm Auto Macro Tube for GFX: B&H Photo / Amazon
Fujinon 18mm Macro Extension Tube: B&H Photo / Amazon / Adorama
Fujinon 45mm Macro Extension Tube: B&H Photo / Amazon / Adorama
