Fujifilm Fujinon XF 8 mm f/3.5 R WR
6. Distortion and field of view
Please Support UsIf you enjoy our reviews and articles, and you want us to continue our work please, support our website by donating through PayPal. The funds are going to be used for paying our editorial team, renting servers, and equipping our testing studio; only that way we will be able to continue providing you interesting content for free. |
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Field of view
As we had photos of starry sky at our disposal we decided to measure the real field of view of the tested lens both for corrected JPEG files and uncorrected RAW images. In order to do that we transformed the pixel layout (X,Y) from the photo into the equatorial coordinate system (right ascension and declination), which locates a star on a celestial sphere. That way we could determine the field of view of the lens with utter precision and in the right way, so for rays of light coming from infinity.In case of JPEG files the transformation was based on 201 stars spread evenly across the frame, with the relative mesh-fitting error of just 64 seconds of arc. The result we got amounts to 120.8 deg with the measuring error of 0.2 of a degree. It is in perfect accordance with the official value provided by the producers; it's nice that Fuji is very honest in their approach because they state the field of view already after decucting distortion correction.
It also means that uncorrected RAW files offer you a wider field of view – in that case our result amounted to 125 degrees exactly, with a bit higher level of error, that of 0.3 of a degree.
Distortion
The real distortion level can be measured only with uncorrected RAW files. In this case you see huge barrel distortion, amounting to -7.43%. When it comes to JPEG files distortion is corrected but not perfectly well – our measurements showed also its barrel variant but on a level of 1.31%.
Fujifilm X-T2, 8 mm, JPEG | |||
Fujifilm X-T2, 8 mm, RAW | |||