# T4i continuous Video AF, CDAF or PDAF?



## MK5GTI (Jun 5, 2012)

ok, i can't wait to see the announcement on friday; I need the continuous AF becoz i shoot toddler all the time, and i can't keep up with MF, my temporary solution is my Sony 5n.

i always want a VDSLR that can do continuous AF in Video mode, but if the T4i video AF performance is same as the Nikon D7000, with sluggish video CDAF, then i don't see why it took Canon that long to bring that kind of AF into DSLR. unless the CDAF they use is the same speed as Olympus EM-5 and Panasonic GX1? that would be interesting!

i hope the T4i or the upcoming 70D would have same performance as the Sony Alpha DSLR thou..... just without the limitation.


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## Synomis192 (Jun 7, 2012)

I believe that the Nikon C-AF in their video mode doesn't work too well. 

But you're right, Canon better have a C-AF that works better than the Nikon.

If it doesn't they'd better call it the T3.5i 

How well does the focusing system work for the Sony Alpha series?

*off-topic*
I didn't know that the Sony 5n has continuous auto focus for video.

I've actually been looking at the 5n as a secondary camera for traveling. Would you recommend the Sony 5n?


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## MK5GTI (Jun 7, 2012)

the Sony Alpha DSLR focus really well in video mode, it is just the same as focusing in photo mode, becoz of their translucent mirrior, so they are able to use Phase Detection AF all the time.

the down side is, aperture has to be wide open, but if you want full control, you lose continuous AF, so not both....

The 5n is great, AF is quicker than the original NEX3 or 5, but still slower than EP3, GF3, and the EM-5. but IQ wise, i am very satisfied with it. For travelling, you can get the 18-200, both Tamron and Sony made one.

if you want it for portrait, there is only 1 lens available if you want bokeh, the 50 F1.8, but it focus even slower than the kit lens, don't know why.....

wait for another month or so, Sonyalpharumors mentioned the NEX 5n successor will come soon, so the 5n price will go down


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## MK5GTI (Jun 7, 2012)

can someone explain how this hybrid AF work for video?

_Live View shooting

Set Aspect Ratio 3:2, 4:3, 16:9, 1:1
Hybrid CMOS AF focusing system * (+ tracking, FlexiZone-Multi, FlexiZone-Single), phase difference detection method (quick mode)
Manual focus (approximately 5x / 10x magnification possible)
* Focusing brightness range: EV 1-18 (23 ℃ in, ISO 100)
Continuous AF can
Can touch the shutter
Real-time image sensor Metering mode Metering
Evaluative metering (315 segments), partial metering (approximately 8.8% of the Live View screen), spot metering (approximately 2.8% of the Live View screen), Center-weighted average
Metering range EV 0 – 20 (23 ℃, ISO 100)
Display two kinds of lattice_


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## preppyak (Jun 7, 2012)

MK5GTI said:


> the down side is, aperture has to be wide open, but if you want full control, you lose continuous AF, so not both....


That seems like a silly solution for AF. And if the lens is wide open, do you mean it would shoot at f/1.8 on your primes all the time? Cause I would imagine that would get old fast, especially if I wanted more DOF. Or is it the other way around, where it always shoots at f/11 (which would make it no better than your standard camcorder)?

Either way, the inability to control the settings manually would be a deal breaker for me


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