Efji, qui tient à être exhaustif parce qu'on lui a appris au catéchisme
qu'on pouvait mentir par omission, nous envoie un long article de
DPreview dont on sait qu'il fait partie du groupe Amazon. Loin de moi
l'idée que cet article pourrait en être faussé, mais quand même...
Amazon existe pour gagner de l'argent et peut donc avoir une certaine
influence sur la rédaction de DPREview et sur les influenceurs qui y
apparaissent.
https://www.dpreview.com/news/0579754933/photo-business-the-rise-and-impending-fall-of-social-media-influencers
Donc, que Mark Pain ait besoin de Nikon et que Nikon ait besoin de
DPReview, ce n'est pas un crime, il faut seulement lire l'article avec
un esprit critique bien affûté.
Cet article comporte 2430 mots. Il va donc falloir restreindre la
lecture aux points cités par Efji : l'autofocus, les artefacts de LEDs
ainsi que les commentaires de Mark Pain sur son D5 et son Z9.
*L'autofocus.*
Efji nous déclare avec un enthousiasme tout juvénile :
"Le Z9 est un appareil génial pour le sport dont l'autofocus surpasse
les réflex."
Que dit Mark Pain ?
Ben, il se contredit plus ou moins :
Q : How does the Z9 compare in terms of performance against your DSLRs?
A : I think it’s revolutionary, in terms of 3D tracking with face
detection. It’s a stunning improvement over the D5 and D6. With sport of
course, it’s horses for courses, and i’m discovering that even with the
the best systems, it’s all very well if you’ve only got two or three
faces in the frame, but as soon as you shoot rugby or a fast-moving
sport like netball, you can’t always rely on it. *So yes there are
massive improvements, but as a working photographer I’m not getting many
more photos in focus than I would with my DSLRs*. Technically though,
it’s incredible, and for anyone without my amount of experience, it will
definitely help them. So far I’ve only used it in human face and eye
priority mode, and the way it sticks to heads and eyes is absolutely
brilliant.
Mark Pain, photographe professionnel, n'obtient donc pas beaucoup plus
de photos au point qu'avec ses réflex D5 et D6. La sophistication
technique du système autofocus, que j'ai déjà signalée, n'apporte guère
de résultats meilleurs sur le terrain.
Q : With the Z9 you get almost complete autofocus coverage, across the
frame. Is that useful to you?
A : Not really, because every part of my experience and learning as a
photographer is geared towards keeping my subject in the frame, as
centrally as possible. I would argue that the two most important factors
for sports photographers are making sure you’re using the right focal
length, and being able to keep your subject within the central 2/3 of
the frame. Very rarely is my subject at the extreme edges of the frame.
Idem. Comme je l'ai dit, mettre des collimateurs partout, argument de
marketing, n'a pas d'intérêt réel.
*Vitesse de suivi de l'autofocus* :
The camera is only as good as what you ask it to do. They don’t learn,
like humans do. It still amazes me how few professional sports
photographers ever change the tracking speed of their AF, for example.
None of us can keep our subject in the middle of the frame all the time,
but *I change my AF tracking speed depending on what I’m shooting, so
that if I know either that the camera is likely to get it wrong, or my
subject is likely to temporarily leave the middle of the frame, I just
turn the tracking speed down a notch so that it doesn’t try to go
hunting for something else*. For example I was shooting a kayaking event
at an Olympic Games, and I knew that my subject was about to momentarily
go underwater, so the autofocus would lose his eyes. I just knocked the
tracking sensitivity down to slow, and when he went underwater for that
moment, the AF didn’t jump off to his hands, or water droplets flying up
or whatever else.
On apprend ainsi que pour avoir de bons résultats, dans certaines
circonstances où le sujet peut quitter le champ, il faut changer la
vitesse de suivi de l'autofocus.
*Les artefacts de LEDs.*
Q : The Z9 features a fully-electronic shutter, rather than a mechanical
or hybrid shutter. I know you’ve had some issues with the dreaded ‘LED
banding’ on advertising screens – can you talk me through it?
A : To date, I’ve shot about ten professional jobs with the Z9, covering
four different sports, indoors and outdoors, and it’s been an issue – I
won’t call it a problem, as such – in about *half of the places* I’ve
been to.
There are two things that are concerning to me – concerning with a small
‘c’. One is that *the effect changes from venue to venue*, I assume
because the LED boards themselves are different [editor’s note -
exposure time is another potential variable].
The other thing that’s annoying is that *even when the LED board is out
of focus in the background, the banding is always pin sharp*. So it
looks like someone’s taken a ruler and a pencil and drawn a line over
that soft blurry part of the image."
Q : Would the LED banding issue affect your ability to sell pictures to
a client?
A : No, probably not, and I need to emphasize that this is an issue that
won’t affect 99% of people considering buying a Z9. I’ll make the switch
to being full mirrorless, I think everyone will, but what I’ll probably
do [for now] is that *if I know I’m being paid by a sponsor to shoot an
event, and there are LED boards, I’ll bring a DSLR along as well,
alongside my Z9*. If I’m shooting for company ‘X’ I want company ‘X’s
logo to look perfect in the images.
Q : Aside from the banding issue, is there anything about the Z9 that
you’d like to see changed or improved?
A : The camera is absolutely stunning. It is more usable by far than
some of its competitors that I’ve shot with. From my point of view as a
working professional though, *the file sizes are way too big. As a
sports photographer I don’t need all those pixels. I still shoot Raw
most of the time, which isn’t very common in the sports world anymore,
and the new compression options save on card space, but they still open
in Photoshop at 130MB,* regardless of the compression mode. That’s still
a huge image size, twice the size of files from my D6. It’s a pain for
my workflow. Currently *the only way I can reduce the output resolution
is to shoot in DX crop mode, which isn’t always ideal. I want a Z9 ‘lite’*.
Ainsi, le Z9 est mieux utilisable en mode DX (APS-C) pour diminuer la
taille des fichiers !
Quelle meilleure preuve que le 24x36 est dépassé en termes de taille
d'image ?
Et à quoi serviront tous ces pixels latéraux ?
Tout cela montre que les choses ne sont pas aussi claires que cela. Le
Z9 montre même des défauts qui lui font préférer un réflex dans
certaines circonstances.
On voit bien que Mark Pain ne veut pas trop fâcher Amazon et Nikon.
La solution ? Amazon vous la donnera :
- acheter un Z9
- acheter un D6
- acheter un D300 (ou un D7000 s'il ne reste pas assez de sous).
Et là, on est paré !