Sony FE 200-600 mm f/5.6-6.3 G OSS
6. Distortion and field of view
Field of view
A full frame rectilinear 200-600 mm lens should give you a range of angles of view from 12.35 to 4.13 degrees. In their official specification Sony states that the offered range of angles of veiw changes from 12.5 at 200 mm to 4.17 at the 600 mm focal lenggth. We managed to check these declarations by taking photos of a starry sky and transforming 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.In case of the 200 mm focal length we used 64 stars for our transformation and they were spread evenly in the photo. The average mesh-fitting error amounted to just 3 seconds of arc. We got a result of 11.66 deg with an error that doesn't exceed 0.1 of a degree. As you see our result is distinctly narrower than the official declaration and it reflects rather 212 mm, not 200 mm focal length.
In case of the 600 mm focal length we used 17 stars and the average mesh-fitting error amounted to just 1 second of arc. The field measured by us amounted to 4.11 deg with a measuring error on a level of 0.05 deg. It seems, though, that the real maximum focal length of the lens might be bigger, reaching near 603 mm. There is a difference between our result and official specifications but it is merely cosmetic. It is important, though, that the producer didn't try to save on the maximum focal length and, as we are going to show a bit later, didn't bring it to its nominal level by allowing a significant focus breathing.
Distortion
In case of the smaller APS-C sensor distortion doesn't give us more serious reasons to complain. At the widest angle of view you get very small pincushion deformations of +0.77% that start to increase with the increase of the focal length. At 300 mm you see +0.93%, and at 400 mm the level is +0.99%. At this point the rise of distortion stops and then its level falls, decreasing at 600 mm to +0.85%. It is important, though, that the results don't exceed 1% at any focal length.
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. |
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
| Sony A7R IIIa, APS-C, JPEG, 200 mm | |||
|
|||
| Sony A7R IIIa, APS-C, JPEG, 300 mm | |||
|
|||
| Sony A7R IIIa, APS-C, JPEG, 400 mm | |||
|
|||
| Sony A7R IIIa, APS-C, JPEG, 600 mm | |||
|
|||
On full frame, understandably, there are far more problems. At 200 mm you deal with pincushion variant of +1.67%. It is not perhaps a very high level but if you remind yourself that the real value of the shortest focal length is 212 mm and if you additionally want to correct distortion to zero, the cropping of images makes the minimum focal length of the tested lens increase to a level of 220 mm or even higher.
At the 300 mm distortion increases to +2.19% and at 400 mm it reaches +2.26%. In case of the maximum focal length distortion is already lower, reaching +2.03%.
In this category the Sony 200-600 mm fares better than the Tamron 150-500 mm which, momentarily, could exceed even +3%.
| Sony A7R IIIa, FF, JPEG, 200 mm | |||
|
|||
| Sony A7R IIIa, FF, JPEG, 300 mm | |||
|
|||
| Sony A7R IIIa, FF, JPEG, 400 mm | |||
|
|||
| Sony A7R IIIa, FF, JPEG, 600 mm | |||
|
|||
