The XT3 AF accuracy on difficult surfaces

With both my former XT2 and my present Xh1 I experienced quite many OOF shots mainly with birds, especially when the emerge from deep water and are covered with water, same with seals and frogs; also with very dark surfaces, white ones, brilliant ones, and all grey feathers of a bird.

This has nothing to do with IBIS since it appears in both T2 and h1

The T3 has no problem at all in such circumstances

below some samples with a very limited light (low clouds in winter), birds of the pond navigating betweens dead lotus plants, slowly

The only way to catch them was to use the smallest size of Af sensor in AFS to get the fastest AF lock since the birds could disppear











behind the plants

I got 100% of tack sharp shots (aprt noise due to High Iso and low SNR..

Formerly that was impossible mission with either T2 or H1 (altogether a 32000 shots experience..)









These are crops to a get a better detailed view, the originals have a wider frame that allowed me to follow the birds erratically moving

Last comments these are test shots and do not pretend to anything else...

Bob

--
Good judgment comes from experience
Experience comes from bad judgment

results in a 200% view..

If you want to see at 100% (actual) record first the photo the open it at 100% on your computer The + view on the DPR viewer due to crop is just ... awful at least on my 24" screen..

One original without crop







--
Good judgment comes from experience
Experience comes from bad judgment

Thanks Bob for these very interesting results. It's incredibly useful to know the limitations of one’s equipment in different circumstances and to have a comparison with similar cameras.

I am trusting that the next iteration of the X-H family will be as good as that of the current X-T3 as presumably it will have the same sensor & processor and maybe, with a bit of luck by then, even some Kaizen fairy dust to improve the focussing still further.

Fortunately, for much of my work the focussing is a little less demanding than the circumstances you mention and so my X-H 1 is fine at the moment. Nevertheless, I am looking forward to the X-H2 in order to get the focussing advantages you find with your X-T3 as it's always good to have some capability in reserve. It will seem a long wait!

Thanks again for sharing your experience with these cameras!

Phil

Thx Phil

I am most pleased with the H1 and its remarkable iBIS but I immediately noticed the difference in sensitivity, accuracy and speed in AFS not talking about AFC and tracking.

These test shots appear by chance (low light, black birds, a very narrow slots to shoot, ideal conditions to test the capabilities of the new AF (not to produce master pieces !!!)

Hi Bob

The ability of your X-T3 to focus on the birds hiding in the reeds is quite remarkable and I really look forward to getting this when the X-H2 comes out in a year’s time (or hopefully earlier!).

I'm also delighted with my X-H1 which I deliberately chose over the X-T3 as I needed IBIS more than the greatly improved focussing the X-T3 offers, although that would be very useful to have! Most of my work is in dark to very dark conditions where I have to operate at low SS (sometimes down to 1/4 s) with lenses wide open & high ISOs. On one occasion it was verging on the impossible to even see where I was going and sadly a tripod was out of the question. However, the IBIS saved the day & I managed to get some reasonable images.

Keep up the good work – much appreciated!

Phil

The X-T3 focus is extremely accurate most of the time. It is challenged by back light and sometimes will fail to focus if the subject is very close and the camera was last focused far away. The fix is to zoom wider and when focus locks, zoom in slowly and focus will stay on the subject. I have also seen it lock focus on nothing and then track tack that nothing as your subject moves focus moves yet it's not if focus. I wish the camera supported clutch focus where you grab the focus ring and it immediately overrides the autofocus.

Tried with the 18-135mm at 135mm f 5.6 far then close AF without problem

Backlit is difficult for most on snesor AF systems

Could you detail the issue of AF on nothing , which AF settings, which lens,....

Fot the moment I find the wide tracking at last operationnal (vs XH1 or Xt2)

Bob

baobob said:

Tried with the 18-135mm at 135mm f 5.6 far then close AF without problem

Backlit is difficult for most on snesor AF systems

Could you detail the issue of AF on nothing , which AF settings, which lens,....

Fot the moment I find the wide tracking at last operationnal (vs XH1 or Xt2)

Bob

Click to expand...

Hi Bob,

I see the af tracking of nothing about 1 in 500 to 1 in 1000 images. Settings AF-C Erratic Tracking and single point or zone. It happens when I'm not on the subject and the camera gives me time to lock on one yet I don't get focus selector on the subject. I can see my subject in frame yet it is OOF and the amazing ting is that the camera will track the OOF nothing. I've seen this when the bird came through the area that was originally focus selected yet the camera changes the focus distance so it's never in focus. It is a user error situation yet quite an interesting behavior.

Morris

Why not trying a CFG 6 = CFG 5 but FRONT instead of AUTO ?

I had a lot of trouble with background with my former XT2 solved in using FRONT

What is your opinion ?

baobob said:

Why not trying a CFG 6 = CFG 5 but FRONT instead of AUTO ?

I had a lot of trouble with background with my former XT2 solved in using FRONT

What is your opinion ?

Click to expand...

Hi Bob,

I don't see background sticking with the X-T3. It will happen if you don't get the focus selection on the subject.

Morris