11-06-2017, 12:41 PM
(This post was last modified: 11-06-2017, 12:42 PM by Brightcolours.)
My EF-S 10-18mm f4.5-5.6 IS STM appears to focus correctly close by (~1.5-2meters) and pretty correctly further away (not sure, I remember it to be 6-7 meters away) on my 6D. Of course, only can try it at f5 max. Have to put them on the computer still, though, to check better.
The f/1.8 makes a huge difference. Even at 3...5 metres away the DoF is not deep. And the higher the resolution the more a100% view shows missed focus although it doesn't look too bad at first look.
I was thinking about the focus abilities in artificial light. All of them do have kind of a frequency, be it 50 or 60 Hz or higher for fluorescent lamps (up to 200 Hz, I think). If the cameras refresh rate for the AF-module comes close to such a frequency or even synchronizes with, the worst what could happen is the camera only switches AF when the light also goes dark. The flicker reduction setting made me think about this frequency thing, but I don't know if the impact is big.
I reckon it is caused by the camera not being able to determine exactly what to use for AF exactly, as the AF points cover quite a bit more territory than they do with e.g. tele-lenses. Having a slower aperture helps a lot in those cases, I would think.
What may help is focusing on large contrast transitions, if any items can be found at the same distance as the subject one wants to focus on. This is something that not only works fairly well with extreme UWAs, but also when experiences very low light levels, IME anyway.
Kind regards, Wim
Gear: Canon EOS R with 3 primes and 2 zooms, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, tubes; Olympus OM-D 1 Mk II & Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ....
11-07-2017, 07:56 AM
(This post was last modified: 11-07-2017, 08:00 AM by Rover.)
That was about what I was thinking once I got the hang of it a little, Wim. When there's a large central subject, everything (mostly) works fine. Of course, one may argue that this is how you should be shooting an ultrawide anyway...
Yes, but that emptiness might be part of what I want to say with the picture?
Like "ooh I'm missing a Rock Kenwell somewhere here" :lol: