If youre in AF-C and fire off a burst the Z system HAS to correct for any focus shift. The aperture locks itself in while shooting and the camera is still adjusting AF.... so why would it not be compensating for any focus shift there may be? This is an old DSLR "issue" hes falsely applying to Mirrorless.
800mm f6.3S PF Review - Thom Hogan
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ricardo00
Well-known member
Your caracal is a beautiful cat! While I was photographing the distant bobcat hunting, I was slowly walking towards it carrying the 800mm with the 1.4TC. And another bobcat popped out of a bush and slowly walked by me. This bobcat was so close I could hardly fit the whole cat in the frame. I sat down but it sauntered past me and kept on going:Thank you. I drew it up in Coreldraw, using clipart icons and also a font set depicting some African animals. But the birds are Chicken, Pigeon, Sparrow I think so more global citizens! I was aiming at extremes in diversity as a rough guide to gauging distances etc. The distances are computed using an online site. I carry this on longer trips printed as a "cheatsheet" with DoF tables etc
Thank you.
Interesting. IME, and from reading, wild cats are challenging to get close to on foot. Being so alert is obviously key to their survival living alongside the most destructive species on Earth and their commensal domesticates, notably dogs. Lion are one exception in the very few places where they they still survive.
A couple of times I've found lions truculent on meeting up but typically they just want to carry on with their siesta or eating etc. If wary they retreat during daylight if treated with due respect, but they can be dangerously cheeky at night... As once when I was engaged in nighttime fieldwork studying bats - treed by lions for most of the night (until they departed at dawn); such that I empathize ever since with baboons forced to sleep in trees
In contrast I've managed only once photographing a leopard while walking over in many years
Caracal along on the periurban fringe habitats in the Western Cape have become more habituated, compared to decades back. I shared a photo of a memorable encounter.
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fcotterill
Well-known member
For the record, comparision and status of the 800 PF in detailed presentation by Brad Hill and also this earlier thread on 800 PF
His overview and review
http://www.naturalart.ca/artist/cameragear2.html#anchor_lenses_800_6.3
[sorry just seen it's already shared above by Lordofthelight ]
His overview and review
http://www.naturalart.ca/artist/cameragear2.html#anchor_lenses_800_6.3
[sorry just seen it's already shared above by Lordofthelight ]
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Tails
New member
I disagree. People looking for more pixels on target without trying to get closer are going to be disappointed by using a longer FL. Heat distortion is the same regardless of focal length, but if you have a shorter focal length, you will try to get closer and get a better picture because now you have less heat distortion. Buying longer and longer glass is not a solution to getting better wildlife pictures.
Getting closer is not always advisable but the 800 also does not overcome atmospheric distortion.
I have had the 800 pf since 5-1-22. I have photographers ask about it because they are having trouble getting "in focus" photos of birds accross a lake etc. with 300, 400, 500 to 600mm focal lenghts. I first alert them about atmospheric distortion not being overcome by the 800mm. Some have shared their images and it is seldom a focus issue but is an atmospheric distortion issue. So first I tell them about atmospheric distortion that is present any time there is a temperature variation between the air you are shooting through and the surface of water (frozen or liquid) or land you are shooting accross. As that temp differential gets larger and/or the distances get greater the impact gets more dramatic.
Unlike Thom whose wildlife photography is mostly mammals from a safari vehicle. I am a run and gun on foot bird photographer with subjects in a wide range of weather, distances, terrain, habitat, sitting, hiding in the brush, running and flying. I am a citizen scientist and search for and photograph a lot of very small birds like sparrows and gnatcatchers and larger like eagles, geese and swans. I hand hold and do not use blinds/hides.
One strong caveat I have about trying to get closer. There are many times it is better that you do not try to get closer to avoid disturbing the animal's hunting, causing nest abandonment or disclosure to predators etc.. No photograph is worth harming the subject by depriving them of food, stressing to the point of exhaustion or exposing them unduly to predators. In those cases the 800mm really shines and I frequently have the Z9 in DX mode so 1200mm equivalent FOV to be able to stay further away.
I have a 1.4TC and carry it sometimes but have not used it on the 800 pf except for tests. Since my subjects and I are on the move and one second I might be shooting a sparrow in the brush at close to minimum focus distance and suddenly a hawk or falcon flys by or vice versa, there is no time to add or subtract a TC and frequently barely enough time to push one button on my lens to toggle between dx or fx mode.
ricardo00
Well-known member
Good points about disturbing the behavior. I have definitely found that sitting and watching from a distance does not disturb wildlife (ie. badgers, bobcats, foxes, coyotes, as well as birds) and they will go about their normal behavior versus when you try to get closer (which often spooks them and they leave_. They are very much aware of my presence, even with the Z9 which is silent. I have seen people with camouflage, etc and the wildlife also clearly know an object is moving closer to them (they are not fooled by a large object that looks like a tree moving closer). It is much better to start at a distance, the wildlife may even move closer if one is sitting still.
The other point for people like myself who go to photograph raptors bringing food to their nests is that there is no way to get closer to a nest (ie. white-tailed kites, hawks, eagles, owls) high up in a tree or the local peregrine falcon nest which is on a cliff overlooking the Pacific Ocean. It is both illegal and dangerous (and beyond my capabilities) to go climb that cliff. Besides one could disturb the chicks. In the past I even rented the 800mm f/5.6 to photograph these nests so will be very happy to just bring my 800mm PF and set it up on a tripod (either with one of the TCs or without). Luckily I got my 800mm PF in time for the chicks.
PS. And heat waves radiating off the ground or rocks on the cliffs is definitely a problem. However no matter what lens one uses, the problem is the same. One has to go early or on a cloudy day so the strong sun we have is not warming up the ground or rocks and causing this problem.
bowline
New member
Thank you all for confirming what I too experienced when I bought Hogan's guide to the D5 of Hogan's content and writing style. Purportedly chock-a-block full with preordained insights based upon secrets gained from his exclusive contacts within Nikon, it turned out to be a slog; page after page of rambling pontification and simulated erudition. However I will remain as gracious as possible since net/net, it ricocheted me straight into Steve Perry's no nonsense but humorously edgy, seat-of-the-pants experience-based approach and this equally clever and enthusiastic forum. One book later and one email exchange with Steve gave me the confidence to shed the D5 for a Z9 (and thanks to you all) with adapter, a pair of TC's, a 70-200/2.8, a 400/4 and the soon to arrive, the heat-stroked, first-ever focus-shifting prime 800. Thank you all.
Worst investment I ever made was Hogan's Z9 book ... never even came close to finishing it. Yup Steve rocks.
Tails
New member
Well, if the aim is to document animals without disturbing them, I don't think 800mm is the tool, a hide is. But a 800mm would help obviously.
Maljo
Well-known member
About Focus Shifting: Camera Labs review of the 800 Z mentions the background sharpens up faster than the foreground when stopping down but looking at the images its almost imperceptible. And, this lens is likely to be used wide open most of the time.
If you had read the comment thoroughly I don't think we do disagree. If you CAN get closer it's better to do so. If you CAN'T get closer more FL puts more pixels on target and heat distortion is the same.
ricardo00
Well-known member
How do you use a hide if the animals are moving around over large distances (crossing the road, etc)?
O
Well-known member
For me i would assume a 600mm F4 would gather more light versus 800 F6.3. in lower light conditions.
Cropping on a 45 Z9 D850 or 60 mp Z8? sensor using a F4 prime would dilute somewhat the benefit of the extra 200mm on a F6.3 lens ??
Adding a TC wouldn't that take the 800 out to nearly F9 wide open..........????
My Achilles heel is always light, i see so many people go home or pack it up when the light gets a little challenging, and i solder on happily.
99% of the time using a large long prime i use a light mono pod or tripod, I also sometimes find on any long large lens the find wind can be a small issue so much so that i sometimes take off the hood to get through.
I like the fact the 800 is 1.4 kg lighter than a 600 F4 FL, the other benefits would i assume be that the 800mm has new Z technology.
I am a total F2.8, F4 lens lover, I look at everything through time light and speed needs, I find for me 600mm is a sweet spot being F4 as well as being slightly more versatile.
I have not used the 800mm and have an open mind, i do love what Nikon has done, yes the weight is great, defiantly don't like the price.
Only an opinion
ricardo00
Well-known member
I go to the birds and a hide is completely out of the question I do not stay in one place. As I noted I cover a lot of ground.
I agree to both points. I would even say that with the 800 acquiring focus can be troublesome in certain light conditions, where the 400 comes up faster. Might be the larger opening of the lens (2.8 vs 6.3).
maikm
New member
Just to point out one error in Thom's review: min aperture is not f/22, but f/32. I'm using small apertures with it all the time, like f/29, to achieve slow shutter speeds like 1/30 while panning. Combined with the low base ISO of the Z9, I really enjoy getting to my desired shutter speeds in most lighting conditions without fiddling with slot-in ND filters.
tclune
Well-known member
It's my understanding that lenses focus with the aperture wide open, then close down just before taking the shot. That's why cameras have preview buttons. FWIW
JoelKlein
Well-known member
Which means that Thom - will all respect - wrote rubbish?
I assume you mean the aperture not the objective lens. If so the 400 is not f/2.8 if you had either the on board 1.4 TC in use or added the Z TC 2.0 to get to 800mm in that case it would be f/5.6.
Two major things that help me focus in low light or on birds with backlighting is having my EV on my Z800 lens control ring to get proper exposure fast without having to take my eye off the viewfinder. The second is having a button on the lens programmed to toggle between DX and FX with one push. Yes I do make these changes on birds in flight hand holding without taking my eye from the viewfinder while tracking and photographing the bird.
fcotterill
Well-known member
to quote the review, "The lens does have some focus shift (to the back), so be careful using it at any aperture beyond the maximum, as the Z System autofocus system won't automatically correct for it." If it is serious, this should show up in the lens on a solid tripod to prefocus on a suitable target, and use focus-peaking to detect a shift at smaller aperturesMaybe - but it's mirrorless so front and backfocus and very uncommon - especially with newer Z lens designs. My 800mm PF is very accurate.
By maximum aperture, I think he is referring to the widest aperture. In this the lens would normally focus wide open at f/6.3, and if you are trying to shoot at f/9 or f/11 you might find that the actual focus is different than wide open. I have not seen that, but technically it is possible. AF Fine tuning would not really be useful for this because the problem is not present wide open. My experience is I'm shooting wide open most of the time anyway, and the added DOF from stopping down should cover any focus shift issues.
Here is an article about focus shift.
What is Focus Shift?
photographylife.com
As Jim Kasson explained for the 35 f1.8S and 24-70 f4S Nikkors, the real world relevance of focus-shift depends on its magnitude relative to the pixel resolution (4um in a 45mp sensor). The magnitude of focus shift across apertures has not been quantified in the 800 PF, apparently. It will be challenging in the lab. And as you say, I've yet to read any complaints from an owner of the 800 f6.3S.
Quantifying focus-shift is challenging, and in any case as Jim concludes if you focus at the final aperture focus shift is not a problem; but it can be only if you focus wide open and stop down before exposure
https://blog.kasson.com/nikon-z6-7/af-s-and-afc-accuracy-24-70-4-nikkor-s-on-z7-at-35-mm/
AF-S and AFC accuracy — 24-70/4 Nikkor S on Z7 at 70 mm - the last word
This is one in a series of posts on the Nikon Z7. You should be able to find all the posts about that camera in the Category List on the right sidebar, below the Articles widget. There’s a drop-down menu there that you can use to get to all the posts in this series; just
blog.kasson.com
35 mm f/1.8 Nikkor S focus shift - the last word
This is one in a series of posts on the Nikon Z7. You should be able to find all the posts about that camera in the Category List on the right sidebar, below the Articles widget. There’s a drop-down menu there that you can use to get to all the posts in this series; just
blog.kasson.com
JoelKlein
Well-known member
Basically AF-C would correct for it. No?
John Navitsky
Well-known member
i think not due to a quirk in how mirrorless af works. it autofocuses with one aperture, then takes the shot with another. but seriously, i doubt this is a significant real world issue since if i’m shooting at f16 or something my dof is increased.
this smells like one of those theoretical issues that people say to remind you they know about them
