Another great video! Just wondering how much exposure settings would affect the AF speed. I notice with my Xt2 that there can be a delay in the AF if it's also trying to get an AE reading at the same time (although I haven't done any full-on testing to see if this is definitely the case) so I'm wondering if shooting with ISO on auto might be slower than a fixed ISO as the camera is trying to process the two things simultaneously. I was thinking another interesting test would to have all the lenses at their respective "wide open" points and shoot at the lowest ISO and keep the shutter at the same speed but change the actual light in the room to see what effect that would have?? YAY Science.
I'm assuming that when you talk about shutter button focusing, you are using a 'half-press' (as opposed to actually taking a picture). If so, then there should be no difference between auto focus speed. I mean which ever button used to start the AF algorithm should be irrelevant. To me that definitely sounds like a firmware issue...unless the circuitry inside the camera is such that shutter button is directly connected (physically wired) to an interrupt pin on the processor.
Thomas, I have been amazed at the quality of the images from the 70-300 but I have found like yourself, quite a few times it not locking focus and this is even with green box indicating focus. However by moving from spot focus to smallest box zone focussing, it nails it every time which is odd. I was shooting deer in very low light and it grabbed them every time. The light was so low I was shooting at 3200 iso and 60th sec on an X-T4 at 300mm f5.6 and they were excellent results, combined with the image stabilisation the zoom performed amazingly. I was wondering whether I had forgotten to switch iff eye auto-focus and it was confusing the spot focussing. Gary
I found the best results were always from the smallest AF point but the consistency between front and back button was the most confusing. But yes in general the 300mm AF speed is pretty great
Sorry this is two different factors. I shot them all at f10 as once you include the teleconverters this is a aperture every lens can achieve e.g. I couldn’t test the 100-400 at f2.8 because it can’t go to f2.8. The other factor is I tested them all 200mm as you’ll get different results at different focal ranges “zoom factor” is what I said but isn’t the best way to describe this. And I choose 200mm as once again it’s a range that every single lens could be at (aside from the 50-140). In short you’ll get different results if you change your focal range or any number of other factors I mention in the video, but this was the most obvious way for me to remove those variables to get comparable results. Hope this clears it all up.
Yeah I think you'd be right, but I can't switch between front and back focus for that. And as it takes me hours to test them all, doing many gave a reliable enough results as apposed to doing a few at a slower speed
@@ThomasBusbyPhotography I could imagine pushing front or back button puts very different demands on the AF system depending the pattern of the shake induced. If your test setup using a remote yields the high hit rate, I‘d consider this a likely explanation :)
The difference we're so extreme between the two that I don't think that little bit of shake would explain it. Not trying to argue as I agree that a timer would make a improvement, but the differences were very extreme I'm some situation
Would have been interested to see results from using the fastest aperture from each lens as well as f/10, after all for sports and wildlife chances are you will be using it wide open for the fastest shutter speed.
I did mention that very quickly in the video that I did test them wide open as well just to compare and the speeds were the same. But in the end a bunch of other factors effect AF speeds and so just have a comparison was the main key.
Another informative video, but the selection process gets more complicated all the time. Are you going to generate a spreadsheet or something to show all the findings. I can see the conclusion getting complicated possibly depending on what you expect or want from a lens. That lens charts looks looks fairly busy. Would there be any difference if a simple horizontal of vertical line was used ? Like a tree branch one would focus on if the bird was strongly backlit ?
Yeah subject and light will be a huge difference for AF and as there are infinit number of options there I couldn't test them all. As for overall bringing all this testing together yes I have something in mind to keep it simple
Great video Thomas. Been watching this series and was going to wait until the end before making a decision on whether to purchase the 70-300 mm. However, a camera store here in Sydney have a sale at the moment and I picked up the lens for $1,146 AUD. Have only been out to use it once and pretty happy with it. Was photographing my daughters cross country running competition and some shots were good however was hit and miss when using continuous focus mode. I don’t use continuous focus very often so I suspect it may have been the user and not the lens. Look forward to the rest of your series.
I'm wondering was is the AF speed of the 50-140 WITHOUT the 1.4x converter? Let's say at 140mm...would it be faster than or closer to the 200mm (0.47sec) then? Because it appears to be slower than the 70-300 which I find surprising. Also, you say the 50-140mm with the 1.4x is 1.30x slower but slower than what? At what zoom? Do you compare the 50-140 at 140 with the 50-140+1.4x at 200 to say it's slower with the 1.4x teleconverter?
I’m sorry I’m struggling to understand your questions. With the 50-140mm I tested it at 140mm. Then added the 1.4x and 2x converters and tested again. And then moved the camera further away until the frame looked the same as if at 140mm and then tested again with both converters. The test has some flaws but I hope this answers your questions
@@ThomasBusbyPhotography Ok but what is the AF speed at 140mm? Because I can't find it in your video. I can only find the AF speed of the 50-140 with the 1.4 converter and I think the converter would automatically slow the AF process so it's unfair for the 50-140... '°¬\
Another great video! Just wondering how much exposure settings would affect the AF speed. I notice with my Xt2 that there can be a delay in the AF if it's also trying to get an AE reading at the same time (although I haven't done any full-on testing to see if this is definitely the case) so I'm wondering if shooting with ISO on auto might be slower than a fixed ISO as the camera is trying to process the two things simultaneously. I was thinking another interesting test would to have all the lenses at their respective "wide open" points and shoot at the lowest ISO and keep the shutter at the same speed but change the actual light in the room to see what effect that would have?? YAY Science.
I had everything for these tests set the same, though when I did test each lens at max aperture the speeds didn't change which was good.
Precious information that will save me hundreds of $$$!
You're welcome
Super lens test, thanks for sharing
Like the song, Young are simply the best 😎. Thenks for this studio about all this lenses. Its a masterclass.
You are simply the best. Sorry haha
Hahaha thanks
I'm assuming that when you talk about shutter button focusing, you are using a 'half-press' (as opposed to actually taking a picture). If so, then there should be no difference between auto focus speed. I mean which ever button used to start the AF algorithm should be irrelevant. To me that definitely sounds like a firmware issue...unless the circuitry inside the camera is such that shutter button is directly connected (physically wired) to an interrupt pin on the processor.
You are correct and yes there shouldn’t be a issue at all, but there was and it was weird
Thomas, I have been amazed at the quality of the images from the 70-300 but I have found like yourself, quite a few times it not locking focus and this is even with green box indicating focus. However by moving from spot focus to smallest box zone focussing, it nails it every time which is odd. I was shooting deer in very low light and it grabbed them every time. The light was so low I was shooting at 3200 iso and 60th sec on an X-T4 at 300mm f5.6 and they were excellent results, combined with the image stabilisation the zoom performed amazingly. I was wondering whether I had forgotten to switch iff eye auto-focus and it was confusing the spot focussing. Gary
I found the best results were always from the smallest AF point but the consistency between front and back button was the most confusing.
But yes in general the 300mm AF speed is pretty great
Hi Thomas, I don't understand why you chose F/10 to rule out the "zoom factor". Can you expand on this? What do you mean by zoom factor?
Thank you!
Sorry this is two different factors. I shot them all at f10 as once you include the teleconverters this is a aperture every lens can achieve e.g. I couldn’t test the 100-400 at f2.8 because it can’t go to f2.8.
The other factor is I tested them all 200mm as you’ll get different results at different focal ranges “zoom factor” is what I said but isn’t the best way to describe this.
And I choose 200mm as once again it’s a range that every single lens could be at (aside from the 50-140).
In short you’ll get different results if you change your focal range or any number of other factors I mention in the video, but this was the most obvious way for me to remove those variables to get comparable results.
Hope this clears it all up.
@@ThomasBusbyPhotography , thank you!
So is F/10 the widest aperture that all the lenses could be at 200mm?
Exactly, once you factor in the teleconverters.
(I can’t recall now if it was f10 or f11 but they were all the same anyway)
Great job!
Thanks!
I‘m wondering if AF hit rate would be more consistent using remote release cable… what do you reckon? Great test! Keep it up!
Yeah I think you'd be right, but I can't switch between front and back focus for that.
And as it takes me hours to test them all, doing many gave a reliable enough results as apposed to doing a few at a slower speed
@@ThomasBusbyPhotography I could imagine pushing front or back button puts very different demands on the AF system depending the pattern of the shake induced. If your test setup using a remote yields the high hit rate, I‘d consider this a likely explanation :)
The difference we're so extreme between the two that I don't think that little bit of shake would explain it.
Not trying to argue as I agree that a timer would make a improvement, but the differences were very extreme I'm some situation
Would have been interested to see results from using the fastest aperture from each lens as well as f/10, after all for sports and wildlife chances are you will be using it wide open for the fastest shutter speed.
I did mention that very quickly in the video that I did test them wide open as well just to compare and the speeds were the same.
But in the end a bunch of other factors effect AF speeds and so just have a comparison was the main key.
Another informative video, but the selection process gets more complicated all the time. Are you going to generate a spreadsheet or something to show all the findings. I can see the conclusion getting complicated possibly depending on what you expect or want from a lens.
That lens charts looks looks fairly busy. Would there be any difference if a simple horizontal of vertical line was used ? Like a tree branch one would focus on if the bird was strongly backlit ?
Yeah subject and light will be a huge difference for AF and as there are infinit number of options there I couldn't test them all.
As for overall bringing all this testing together yes I have something in mind to keep it simple
hmm the 70-300 with TC misses with shutter af is a bit concerning to me. I don't use back button focus.
It might just be a issue with my exact test, but worth testing your self if back button AF isn’t something you want to try
Great video Thomas.
Been watching this series and was going to wait until the end before making a decision on whether to purchase the 70-300 mm. However, a camera store here in Sydney have a sale at the moment and I picked up the lens for $1,146 AUD.
Have only been out to use it once and pretty happy with it. Was photographing my daughters cross country running competition and some shots were good however was hit and miss when using continuous focus mode. I don’t use continuous focus very often so I suspect it may have been the user and not the lens.
Look forward to the rest of your series.
What camera do you have?
@@ThomasBusbyPhotography I have an X-S10.
I'm very sure the xs10 has the same AF system as the xt4.
Have a look through the menu under AF/MF and see if there are different tracking options
at 3:00 -- why does the 70-300 have lens hood on and the others dont? It makes it look too big this way
No reason, just depends on if Fuji sent it to me with a hood or not
I'm wondering was is the AF speed of the 50-140 WITHOUT the 1.4x converter? Let's say at 140mm...would it be faster than or closer to the 200mm (0.47sec) then? Because it appears to be slower than the 70-300 which I find surprising. Also, you say the 50-140mm with the 1.4x is 1.30x slower but slower than what? At what zoom? Do you compare the 50-140 at 140 with the 50-140+1.4x at 200 to say it's slower with the 1.4x teleconverter?
I’m sorry I’m struggling to understand your questions.
With the 50-140mm I tested it at 140mm.
Then added the 1.4x and 2x converters and tested again.
And then moved the camera further away until the frame looked the same as if at 140mm and then tested again with both converters.
The test has some flaws but I hope this answers your questions
@@ThomasBusbyPhotography Ok but what is the AF speed at 140mm? Because I can't find it in your video. I can only find the AF speed of the 50-140 with the 1.4 converter and I think the converter would automatically slow the AF process so it's unfair for the 50-140... '°¬\
(sorry I'm French and it's not easy to write English without sounding like a child...)
No worries at all
Ok but…what is the AF speed at 140mm? 😂
I am assuming that you used the Xt4 for your autofocus testing?
Ahhh yes I did forget to mention that but you assume correctly
15th.
I think your slipping buddy
The curious thing is: back button AF is the same AF as shutter button AF . Technically no difference.
I thought so too, but In some cases it was a VERY obvious difference