r/NikonZ8

Are Nikon firmware updates sufficient to accommodate the dynamic range of Sony's new DGO?

Now that Sony has implemented Dual Gain Output on the recent Alpha 7V camera (https://www.reddit.com/r/SonyAlpha/comments/1piova1/a7v\_photonstophoto\_dr\_data\_is\_released/) and is preparing to do so on the next version of the Alpha 7R, achieving a significant increase in dynamic range, it would be appropriate for other manufacturers to respond with updates to their cameras.

The new Sony uses DGO automatically only when shooting at low ISOs and with the mechanical shutter and relatively slow frame rates, allowing it to take two sensor readings during the shot and then combine the two readings for DGO into a single RAW file.

The slow frame rate must allow for two readings and the result to be combined into a single RAW file.

Shooting with the mechanical shutter, which remains closed until the next shot, must allow data to be collected from the sensor (pixels excited by light) twice before the sensor is reset and can once again receive light and new information.

The increase in dynamic range resulting from DGO is particularly interesting for landscapes, object photography, and perhaps portraits: that is, where the low ISO sensitivity that allows it can be utilized.

The sensor readout time of the new Sony (about 15 ms) is much slower than that of the Nikon Z9 and Z8 (less than 4 ms) and even slower than the Z6 III (about 10 ms), but it seems that Sony takes two readings in this time, while Nikon takes only one.

The two readings of the Sony DGO can be compared to two shots taken in very rapid succession; in fact, the sensor will be sensitized for the duration imposed by the mechanical shutter, and the two readings are made on this data before the shutter can open again and reset the sensor, allowing it to record new information.

Of course, the new Sony, also because it is the latest arrival, has a faster processor than other cameras (Sony, Nikon, Canon, etc.), and this gives it an advantage, but its sensor readout times are certainly not lightning-fast.

What are the alternatives to Sony's new DGO, which can be used on other cameras?

The "old" HDR function, which uses bracketing with multiple shots, is not suitable because not only would you need a PC to combine them into an editable RAW file, but the sum of the shutter speeds would always be so long that it would only be used with still subjects (not even for landscapes with a bit of wind, water, animals, and moving objects).

A more modern function would be needed that uses the processor to merge data, even from just two very close sensor readings (without using the processor to perform further processing on a long sequence of rapid shots) into a single shot. Ultimately, the sensors are optimized for two different ISO values, and the post-shoot processing times could be similar to those of long-exposure noise reduction.

This question therefore arises for photographers who already own advanced and fast cameras like the Nikon Z 8 and Z 9, but also the Z6 III, primarily for landscape and object shots (and possibly portraits). Is it possible to improve the dynamic range of a shot, achieving exposure times fast enough for these subjects (i.e., without using continuous shooting, which Sony also offers to achieve the same goals)?

If the Nikon Z 8, Z 9, and Z6 III are capable of shooting RAW at 20 fps and 14 bits (and simultaneously saving the twin JPEG and applying the processing), this means that to obtain two consecutive shots, the current times are 100 ms (also necessary to process and compress the corresponding JPEG with the chosen settings).

But if we consider that for the two flagship cameras, the times for two consecutive sensor readings are less than 8ms (less than 1/100") and that there's no need to waste time processing two JPEG files, if the memory buffer size could hold the data from two 14-bit RAW readings, the camera could then take all the time necessary to process the two readings and combine them into a single 14-bit RAW file, and from this also create the corresponding JPEG or HEIF file.

It could be a new single-shot mode "Landscape 2 read Max Dynamic Range", which would only work up to ISO ... (for example, the two base ISO values) and only with shutter speeds slower than ... (1/100" would already be sufficient).

In summary, there are three technical issues that can enable this process:

1. Memory size – can it hold two 14-bit RAW readings?

2. Time required to perform two consecutive readings and save them to memory (e.g., 1/100”).

3. Processing time for the two readings to produce a single 14-bit RAW file and extract a JPEG or, better yet, HEIF file.

Is Nikon capable of doing this by reprogramming the Expeed 7 processors on flagship cameras?