FYI - Fuji af performance in low light vs Sony RX 1

[GaryLH]

Below is a cut and paste from a forum thread that was started by Ray about his experiences w/ Sony RX 1... This cut and past in particular is about his torture test of the xp1, x100 versus the rx1 in low light af performance and the difference in performance he found w/ the Fuji's simply by switching to c-afs.

Here is link to original thread.
http://www.seriouscompacts.com/f38/sony-cyber-shot-dsc-rx1-first-impressions-low-light-shots-17305/

Gary

------------------------- cut and paste ----------------------------------

Between Mike's video above and getting called out on a similar analysis on the DPR Sony forum, I've really learned something today that I probably should have known before this, given that I've been shooting with either the X100 or X-Pro for about two years now. C-AF is overwhelmingly better in low light on the Fujis than S-AF. I think I remember hearing this in the early days of the X100, trying it and not finding enough difference to pay much attention to, and then more or less rejecting the idea ever since. But I guess as Fuji has improved its firmware and then released the ILC models, they really got their act together on this. I just finished doing a low light torture test of sorts, using the X-Pro and the RX1. The RX1 was in S-AF (there's really only one AF mode on their little selector switch - the other options just give you partial or full manual focus), the X-Pro in both S-AF and C-AF. S-AF to S-AF the RX1 was immensely better than the Fuji, locking on consistently where the Fuji would hunt and hunt and only occasionally lock on eventually. BUT, switch the Fuji to C-AF and the cameras behaved more or less identically. Almost no hunting, consistently locking on at the first pass. And at basically the same speed. Couldn't really find a difference between them.

So, I feel like I just got another really good low light camera - I've sort of run from the X-Pro in tough focussing situations in low light. Its sensor is great in low light and when there's something to focus on, the images are great. But in low contrast situations, it was nearly impossible to get it to lock focus. Now I know it can - as long as we're using C-AF. I should have known this before now, for sure...

 

[Buzz40]

Thanks, Gary. Good tip. Will give it a try as I haven't really played around with S AF mode yet. Then again, even shooting by candle light at 6400ISO and f1.4 at sub 1/50 sec exposures, I've had pretty good luck at locking on focus. Just have to find a good spot of contrast.

 

[PatrickT]

Interesting...

Not sure I've ever used AF-C on my X100. I'll have to try that out!

 

[GaryLH]

From my experience w/ the rx100, it seems to be doing at least some sort of partial continuos. I have noticed that the LCD screen will show different things come into focus w/o using the half shutter press.. It always made me wonder if they were at least doing a periodic sample of possible next subject that maybe focused or it could be just my imagination.. To a fast enough CPU, 500 milliseconds can be an extremely long time.

Gary

 

[David_Manning]

Gary, I thought the same thing about my RX100. I wonder if disabling facial recognition would change the camera's behavior. I usually see focus "shifting" after a half-button press when a face, or another face, enters the field of view.

I'm too lazy to check it myself 🙂

 

[GaryLH]

Gary, I thought the same thing about my RX100. I wonder if disabling facial recognition would change the camera's behavior. I usually see focus "shifting" after a half-button press when a face, or another face, enters the field of view.

I'm too lazy to check it myself 🙂

David,

When I first starting noticing it, I did not have facial recognition on... It is one of the options I always turn off until I get used to the camera.

Gary