I'm not Larry, but ...

The formula that Larry gave is known as the "thin-lens formula." It describes how the light travels through an "ideal" lens consisting of a single thin element. In that case, the object distance is measured from the object you are focusing on and the middle of the element and the image distance from the middle of the element to the sensor. In this ideal case, the object distance + the image distance equal the distance from the sensor to the object.

Real life photographic lenses are thin though, but the thin-lens formula still works pretty well as an approximation. To be more accurate for real lenses, you measure the object distance to the "entrance pupil" and the image distance from the "exit pupil". Those locations depend on the lens design but you could roughly approximate them by assuming the front element and rear element surfaces. As you can see, the object distance + the image distance does *not* equal the distance from the sensor to the object, but is close except for object distances that are close to the lens.

Sure, grey market could be the explanation.

MT, you're about as connected and informed as anyone, but there seem to be some units out there -- perhaps pre-release. Check out the
thread on Fred Miranda's site.

I love the image.

It seems to disagree with you though. The EXIF says 1/3s, 24mm, f/11, ISO 64 (24-70/2.8 lens on a D810 body).

In the DxO list, the D5 is within a 1/3 stop of the Df, so they're all pretty close. Close enough that you wouldn't likely see the difference.

IIRC DxO does pretty much the same thing Bill Claff does -- in both cases they find the ISO that interpolates to a goal dynamic range value. Bill's is something like 6.5 PDR and DxO was something similar. Neither takes very high ISOs like 12800 into account in any way.

The PDR graph I posted the link to though does allow, however, someone to ask the reverse question, "what is the PDR at ISO 12800?".

Well there's this.

The S-series is intended to be the Z-mount high-end, gold-ring equivalent. Non-S-series lenses could be consumer-grade, or meet other special characteristics -- just like F-mount lens catagories.

Look closer. Both have serial numbers that start with 30xxxxxx. I like buying used Nikons from UsedPhotoPro because they report the serial number and shutter count. Though I haven't bought form them, mpb.com does also.

I should have been clearer. I should have said non-S-series Z-mount lenses.

The lens roadmap Nikon put out was just for S-series lenses. They've said that they'll be making other non-S series lenses in the same timeframe, but they don't have a roadmap for those.

Does this qualify?

or perhaps this?

Did you actually try it with a flash or flash controller attached? The Z bodies recognize at least some flashes and controllers and automatically go to "d8: off" mode while the hot-shoe is occupied. My Godox flashes and transmitters for instance do that on my Z6. It works quite nicely.


EFCS replaces just the front mechanical curtain with an electronic equivalent -- just like the name says. The rear curtain with EFCS is mechanical.

Silent is electronic for both front and rear (and thus silent). They are completely separate modes with completely separate settings.

If you're OK with using your SD cards for now, you might want to wait until the CFExpress (XQD 2.0) comes out. They are supposed to be faster, cheaper, more available and upward compatible with a firmware mod (which hopefully Nikon will do for their XQD bodies). There's a good chance they'll be available in 2019 according to rumors. Even if the D500 doesn't get the firmware to handle CFExpress, it stands to reason that XQD cards will drop in price once CFExpress hits the shelves.

I'd suggest remeasuring before you buy your additional reflector-based grids, diffusors, barn-doors, etc. I'll bet it's 7".

I'm guessing that stitching water waves was not easy. It turned out quite nice though.