Leica announced the SL3 on 8 Mar 2024 and I managed to get mine on 10 Mar 24 as I pre-ordered it on 1 Mar 24 from Sue.  The Leica SL3 represents the pinnacle of Leica's renowned craftsmanship and innovation in the realm of full-frame mirrorless cameras. With a blend of cutting-edge technology and classic design, the SL3 caters to both professional photographers and enthusiasts alike.   Having been fortunate enough to own the SL, SL2, SL2-S and now the SL3, one can clearly see the evolution of the system from 2015 to 2024.

These are some of the new features on the SL3:

- Smaller and lighter body

- 60MP BSI sensor with triple resolution

- Tilting screen

- Maestro IV Processor

- Dedicated ISO top dial

- Electronic power button

- 8K video recording

- New Leicons interface

- Phase detect autofocus with object recognition (animal only as at FW1.10)

- Faster WiFi

- Accepts CF Express Type B Cards

- Timecode sync connector (dunno what it is as I don't shoot video)

- Fastest shutter speed is only 1/16,000s instead of 1/40,000s on the SL2

- Flash sync speed dropped to 1/200s instead of 1/250s

Listed below are the detailed review of its features:

Sensor and Image Quality:

• The Leica SL3 features a 60MP full-frame BSI CMOS sensor, delivering exceptional image quality with stunning detail and dynamic range.  This sensor is the same as the ones used in the Q3 and M11.  
• The sensor's low-light performance is remarkable, allowing photographers to capture clean and noise-free images even in challenging lighting conditions.
• Tested the SL3 during the launch in Singapore and managed to take some beautiful photos of Day Jitprasong in challenging lighting conditions.

Maestro IV Processor:

• Powered by the Maestro IV processor, the SL3 offers lightning-fast performance and responsiveness.
• The processor enables continuous shooting at up to 15 frames per second, ensuring that you never miss a decisive moment.  However, due to the increased resolution, it is lower than the SL2-S 25 frames per second.

Autofocus System:

• The SL3 boasts an advanced hybrid autofocus system with Phase Detect Autofocus & Object Detection, providing precise and accurate focusing across the frame.  However, I can't seem to notice much of an improvement over the SL2.
• With face detection and tracking capabilities, the autofocus system effortlessly keeps pace with moving subjects, making it ideal for capturing fast-paced action and sports photography to a certain extent.  It will still cannot compete against the likes of the mature Sony, Canon, Nikon or Olympus AF system.  The AF system for the Sony A9iii is insane and there is no way a Leica can beat it.
• The inclusion of the Animal Detect Autofocus algorithm creates a rectangular block on the animal, however, it does not lock onto the eyes.  Maybe the new firmware may change this as this is still in the beta stages.

In-Body Image Stabilization (IBIS):

• Equipped with a 5-axis sensor-shift image stabilization system, the SL3 compensates for camera shake, allowing you to capture sharp images at slower shutter speeds and with longer focal lengths.  Although some influencers commented that this is a step backwards from 5.5 stops from the SL2, the 5 stop IS is not gonna be noticeable.
• IBIS also enhances the performance of adapted lenses, making it a versatile choice for photographers who use a variety of optics.

8K Video Recording:

• The SL3 supports high-resolution 8K video recording at up to 30 frames per second, delivering cinematic quality footage with incredible clarity and detail.
• It also offers C8K at 10-bit 4:2:2 H.265 recording, providing greater flexibility in post-production for color grading and editing.
• As I don't really shoot videos, I can't comment on these new 8K features.

Weather-Sealed Construction:

• Crafted from a robust magnesium alloy and featuring extensive weather sealing that is rated IP54, the SL3 is built to withstand the rigors of professional use in challenging environments.
• Whether shooting in rain, snow, or dusty conditions, photographers can rely on the SL3 to deliver consistent performance without compromising durability.  There were some reports that Leica actually tested the SL3 all the way from -40C to 70C.

Intuitive Handling:

• The SL3's ergonomic design and intuitive controls ensure a seamless shooting experience, allowing photographers to focus on capturing the moment without distractions.  The SL3 is 5mm narrower in width, 3mm shorter in height and 76g lighter than the SL2.  Due to the fact that the SL3 is slighter shorter in height, my little finger is dangling in mid-air........Will definitely need to add the new HG-SCL7 handgrip to my setup.
• The customizable buttons and new ISO dial on the top plate enable users to tailor the camera settings to their preferences, enhancing efficiency and workflow.
• The new 2.3 million pixel tilting screen is a boon for macro photographers as we don't need to bend down too low to capture the low-lying insects.  The first time I used it, I was kinda amazed how robust the screen was as compared to other cameras.  
• Now that the SL3 is smaller, I wonder how it stacks up to the similar Panasonic Lumix S5ii in terms of size.

Integrated Connectivity:

• With built-in Wi-Fi and Bluetooth connectivity, the SL3 enables seamless wireless sharing of images and remote camera control via the Leica FOTOS app.  The wifi on the SL3 is 10 times faster than the SL2 and I am amazed by the transfer speed.  The download speed is really incredible now....In the past, I'd only use the WiFi downloads if I forgot to bring the cable.  Now with the increased download speed, I'll be using it more than the SL2.
• The SL3 also features a new CF Express Type B & UHS-II SD card slots for flexible storage options and efficient file management.

Optical Viewfinder and High-Resolution LCD:

• The SL3 features a high-resolution electronic viewfinder with a refresh rate of up to 120 frames per second, providing a smooth and immersive viewing experience.
• It also boasts a 3.2-inch touchscreen LCD monitor with a tilting design, allowing for easy composition and review of images from various angles.

I didn't know a pineapple looks like this from the top.

Compatibility and Lens Ecosystem:

• The SL3 is compatible with Leica's growing range of SL-series lenses, renowned for their exceptional optical quality and craftsmanship.
• Additionally, with the use of adapters, photographers can leverage Leica's extensive lineup of M and R series lenses, expanding their creative possibilities.
• However, I would wish Leica could give macro or product shooters the ability to have Focus Stacking/Bracketing or Live-Composite via a firmware update.

In summary, the Leica SL3 is a formidable tool for photographers seeking uncompromising image quality, performance, and durability over the SL2. From its high-resolution sensor and advanced autofocus system to its robust construction and intuitive handling, the SL3 embodies the essence of Leica's commitment to excellence in every aspect. Whether shooting stills or video, in the studio or the great outdoors, the SL3 empowers photographers to unleash their creativity and capture moments with unparalleled precision and beauty.