XTi vs 1V Auto Focus Speed

I bought a used 1V. It seems to be in good shape but when I compare it's

autofocus speed against the speed of my XTi I find that the XTi hunts less (in

low contrast\dim light) & focuses faster.

I'm using the XTi's center focus indicator versus whatever the 1V selects. EF

50mm 1.4 & 300 F4L lenses. Can anyone comment?

Thanks.

Have you try to use only the center focus point on 1V when comparing focusing speed?

What Mike said...

 

How can you make a decent comparison if you don't have both cameras set up the same way?

 

Also, remember that the XTi is a brand new camera, while the 1V is over seven years old. While I have never used a 1V, I do use a 1D, which should have a comparable AF system as they were released not too far apart from each other and are of the same basic design. I find that my friend's XTi has an autofocus that seems not to be noticeably better or worse than the 1D (when it comes to anything but fast-moving sports in AI servo mode). If anything, the XTi acquires focus more quickly than the 1D in very low light. The apparent extra magnification of the XTi might be helping this, but I think it is more likely due to the seven year age difference.

 

Keith

What Mike and Keith said...

 

The XTi may even have a better AF system in low light but your comparison doesn't prove or disprove it is better than 1V. I have no experience with XTi but my old 20D was very comparible to my 1D in one shot mode but in terms of tracking in AI Servo mode my 1D was much better.

 

Try your tests in terms of "tracking" in low contrast/dim light and good light.

 

My guess is that if you use single center AF point on both cameras you won't have the tools to measure which one is faster. Both are fast. Use the 1V when you need fast AF (good light?) and 10fps.

Actually I remember reading something about new Digital Rebel (first generation model) out performed 1Ds in a cener sensor focusing speed at a certain low light condition (around EV 2 - 6 range, I think) from Popular photo magazine few years back. I'm sure that the new Rebel XTi must have equal or improved focus technology to out perform the old Rebel one, so it doesn't really surprises me. However, to be more accurate and fair, you should compare center focusing points on both cameras. Also note that the size of those two center sensors are different so that you may want to vary brightness and size of the subject (fill the entire frame or 2-5% around the center).

Thanks for those who answered.

For static subjects & one-shot mode the XTi c\w center spot selected is faster & surer (at least to my eyes) when compared to the 1V c\w center spot selected.

In low contrast light & for static subjects the XTi\center spot is definately faster then the 1V & camera selected spot(s).

I'm going to shoot birds tomorrow so I'll compare the XTi & 1V in AI Servo.

The AF sensor on the XTi is the same sensor used in the 20/30D. I have both the 1v and the 20D and have also observed that the 20D focuses faster in lower light than the 1v. In regular lighting however, the 1v shines as it is faster (blazingly fast!) and more accurate, and is very impressive with the PB-E2 drive attached which allows very accurate predictive AF at 9fps and 10fps in single shot. It acquires a subject and tracks it much better than the 20D does and produces more fast action keepers than the 20D, although the 20D is no slouch by any means. Of course the 1v is working with 45 AF points of which 7 of those are cross-sensors as well, so that helps. Have fun with the comparison; you should be able to get a lot of great shots with your XTi and a good lens, but your 1v will probably nail most of the birds most of the time in normal lighting conditions. Let us know what your findings are...I'm interested in hearing about your experience with these two side by side. I love my 20D to pieces, but the 1v is legendary.

 

Andy

Canon still advertise the EOS 3 with the 300 2.8 as being the worlds fastest focusing lens

 

So this is an interesting development

 

Not really the same topic, but my EOS 3 focusses quicker and more accurately than my

EOS 5D - with centre spot selected.

 

This becomes readily more apparent with low light levels

 

My EOS 5D focus is faster than the EOS 1NRS...

 

When using the Centre spot with expanded focusing area, I find it is on a par with the EOS

3, except it can get too clever for its clogs and looses the plot.

 

This is particularly noticeable in Aviation photography, where the EOS 3 really wipes the

floor clean. The EOS 1NRS in this situation outperforms the 5D.

 

And to be clear I am most impressed with the 5D's focusing abilities. However am

searching for something digital more in line with my EOS 3, so keeping a weary eye out for

the EOS 1D range but will test an EOS 400D just to see for myself that it really is better,

which I will be stunned to see.

 

Cheers G

I don't know about the XTi, but my wife has a 30D and I have a 1V. The autofocus system of the 30D, albeit pretty fast, is no match for that of the 1V.