Knorp
Well-known member
Could have been worse though ...
Re-thinking basic assumptions
‘For the G Master lenses we decided we would assess the spatial frequency at 50 lines per mm,’ says Ohtake: ‘Usually lens makers, including ourselves, evaluate lenses at 10 and 30 lpmm (or 10, 20 and 40 for Carl Zeiss-branded optics).’
‘At the start of the process we all agreed we should change the spacial frequency [to a more challenging target],’ he says: ’but which is best to get good performance? We could design for 100 lpmm but the lens would become very bulky and long - which might not be a very practical lens. A balance of the size and the optical performance was very important.’
The target of 50 lpmm wasn’t dictated by the company’s 40MP camera or 4K video, he says. ’All our FE lenses were designed for at least 40MP. Because we have an image sensor team within Sony, we get to see the sensor roadmap, so we’ve been designing for this all along with FE. With the G Master we’d like to make lenses that can be used forever.’.’