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Ultracker Aleta S2C is a 360 camera that can capture 12K (66-megapixel) 360 photos and shoot 360 video in 4K. With one of the highest photo resolutions on the market, it is emerging as the virtual tour camera of choice, and it is now available in the US.  I’ve been using Aleta S2C since August 2018 and here are is a detailed hands-on review, with full-resolution sample photos April  26, 2019 update: 7-shot in-camera HDR mode and auto exposure bracket 

Ultracker Aleta S2C review
LED banding resolved
Firmware 104 improves stitching, resolves LED banding
Aleta S2C update adds Google Street View compatibility and other improvements
Aleta S2C update adds Google Street View compatibility and other improvements
Aleta S2C WDR increases dynamic range
Aleta S2C WDR increases dynamic range

Table of Contents:
Summary and Review
Specifications and features
Street View compatibility
Time lapse mode
How to shoot and stitch on Aleta
Sample photos
WDR sample photos
HDR sample photo (firmware 1.03.37)
Firmware 1.04
How to update the firmware
Summary; Price and availability

Updates
December 28, 2018 update: Street View compatibility + improved stitching.
October 31, 2018 update: new samples with improved stitching
August 31, 2018 update: availability, how to shootnew samples.
June 18, 2018: New sample photos from prototype.
May 15, 2018: features updated, price and availability updated

Executive Summary and Review, Tutorial, Comparisons, and Sample

Here is a review, tutorial and comparison of the Ultracker Aleta S2C.

Ultracker Aleta S2C sample photos and comparisons with Insta360 One X (reviewed here), GoPro Fusion (reviewed here), Xiaomi Mi Sphere (reviewed here) and Panono (reviewed here):

Background

There are many 360 cameras on the market, and they’re leapfrogging each other with video resolution.  But most 360 cameras have a photo resolution of only around 16mp and very few have a resolution higher than 32mp.  Seeking to fill the need for high resolution photo, Ultracker’s Aleta S2 is a new 360 camera that captures 12K (66 megapixel) 360 photos.  There will be two versions of the Aleta S2: S2C (Light) and S2 Pro (Professional), which differ in video quality.  The S2C is now available, while the S2 Pro is still being developed.

Here is a product video:

Ultracker Aleta S2 and S2C Specifications and Features

Here are their specfications.  Note: Aleta S2 and S2C specifications are the same, except for the video framerate at 4K.

Lenses five 2.6mm fisheye lenses (four horizontal + 1 zenith)
Aperture f/2.2
Field of view Fully spherical
Sensors five 14mp CMOS sensors
Photo resolution 11520 x 5760 (66mp)
Video resolution 3840 x 1920 @ 30fps (S2 model)
3840 x 1920 @ 10fps (S2C model)
3072 x 1536 @ 24fps
1920 x 960 @ 30fps
Time lapse 7680 x 3840 @ 2fps
5760 x 2880 @ 3fps
Live streaming HDMI, Wi-Fi, RTMP, RTSP
Audio Line in, Microphone input
Stabilization 9-axis IMU (gyroscope, accelerometer, e-compass)
Connectivity Wi-Fi 802.11 b/g/n
Micro USB
Micro HDMI
Storage Micro SD
Compatibility Android, iOS
Battery 18650 Li-ion battery (2600 mAh) x 2
Operating temperature -10C to 40C (14F to 104F)
Operating humidity 0 to 90%
Dimensions 103mm diameter x 158mm height
Weight 425g

One of the key features of Ultracker is its in-camera optical flow stitching.  For users who prefer to stitch with their own software, it is also possible to save the photo as five unstitched photos.

Aleta also features WDR, an HDR mode that blends and stitches two exposures automatically, and HDR mode (which is actually an exposure bracketing mode). The in-camera stitching and HDR mode will be particularly useful and convenient for virtual tour photographers.

Street View compatibility

As of firmware 1.03.37, the Google Street View app can now control the Aleta S2C and wirelessly import its photos with GPS metadata.  The only current limitation is that in HDR mode, Street View keeps crashing.  Hopefully, Ultracker will fix this issue.  Firmware 1.03.37 also improved the stitching quality (see below).

Time lapse mode

In addition to photos, Aleta S2C also has a time lapse mode.  Here is a sample shot by Ultracker:

 

How to shoot and stitch with Aleta S2C (updated April 26, 2019)

Shooting with the Aleta is easy.  You can either shoot with the on-camera controls, or the app.  The on-camera control is limited to a shutter (although it can use a self-timer).  Startup takes a while on the prototype (around 30 seconds, including the time to read the Micro SD card).  However, there is a standby mode that can allow it to resume shooting in a couple of seconds.

To change settings, you need to use the app. You can download the app on the iTunes app store or Google Play Store.  Once the app is installed, you can connect the camera to the app using your phone’s Wi-Fi.  The password will be shown on the LCD display of the camera. By default, it is 88888888 (eight 8’s).  I recommend turning on the camera (waiting for it to complete its startup), launching the app and then tapping on the app’s Wi-Fi icon on the upper right side.  In most cases, the app will connect to the camera automatically.  In my experience, this connection method is more reliable than using the phone’s Wi-Fi settings to connect to the camera.

Aleta S2C app controls

Aleta S2 stitches photos automatically in-camera, in 360 equirectangular format, saved into the Micro SD card.    You don’t need to do anything.  However, it also has the option to save a photo as five unstitched photos, for stitching with 3rd party stitching software (this is called “Raw mode” even though the photos are JPG not Raw).

Aleta S2C has noticeable fan noise and the battery life seems quite short.  On the other hand, it uses inexpensive Type 18650 batteries which are readily available for low cost at many electronics stores.

The Aleta S2C’s standard photo mode has limited dynamic range and excessively high contrast, but it has three waysto increase dynamic range: WDR mode, HDR mode, and auto exposure bracketing.  WDR mode can be used for both photos and videos.  The user can adjust the intensity of the WDR effect.  From the app’s main screen, tap on the three dots on the bottom left corner, tap on the WDR icon, and adjust the slider.  You’ll be able to preview the effect in realtime.  WDR will not result in ghosting and can be used for day or night photos.

Aleta S2C WDR mode
Aleta S2C WDR mode

HDR mode is a true in-camera HDR mode for photos.  It can take 3, 5, or 7 shots and fuse them in-camera.  To use this feature, switch to photo mode on the left side of the screen and choose Day or Night (it doesn’t work for Sports or Manual), then make sure HDR is selected.  To adjust the settings, tap on the three dots on the bottom left corner and tap on the gear icon to bring up the Settings.  In the Settings screen, scroll down and tap HDR Mode.  There are three presets, and a manual option:

Weak: 3 shots, 1.5EV exposure intervals, HDR effect 60
Medium: 5 shots, 1EV exposure intervals, HDR effect 80
Strong: 7 shots, 1EV exposure intervals, HDR effect 60
Manual: user selects number of shots, the exposure interval, and the intensity of the HDR effect.

Aleta S2C HDR mode
Aleta S2C HDR mode

Finally, auto exposure bracket takes a bracket of 3, 5, or 7 shots, with constant ISO and of course aperture.  Each exposure is stitched identically to the other two exposures, making it easy to fuse them in an HDR program such as Photomatix.  See below for samples.  To use AEB mode, tap on the exposure mode and tap on the right arrow to bring up additional exposure modes, one of which is AEB Org mode.

To change the settings on AEB mode, tap on the 3 dots on the bottom left, tap on the gear icon to bring up the settings screen, and scroll down and tap on AEB mode.  The settings for AEB are similar to those of HDR mode except there are no presets.

Aleta S2C AEB mode
Aleta S2C AEB mode

Aleta S2C retains the most recent settings for exposure mode and self-timer.  For example, you can set the self-timer to 10 seconds, and the exposure mode to HDR, and Aleta S2C will retain those settings even if it is powered off.  It is therefore possible to shoot a virtual tour without using your phone, although I recommend using a phone to check your composition.

Aleta S2C Sample Photos and Photo Quality (updated January 11, 2019)

Aleta S2C’s strength is its excellent detail, which is made possible because each of its five lenses uses the full sensor, unlike most 360 cameras that fit a circular fisheye into rectangular or square sensor, and thus are unable to use a significant portion of the sensor. By using the full sensor, the Aleta maximizes the detail from each of its sensors.

Although Aleta S2C has a fifth lens that faces the zenith, its stitching is on the whole less smooth than some professional 360 cameras such as the Insta360 Pro.  This is because each component image from the Aleta S2C has very little overlap with the other images, and therefore it is much more difficult to get smooth stitching.  However, Ultracker has been working hard on improving its stitching with every update.  The latest update (Firmware 1.04 released January 11, 2019) improves the stitching noticeably, as seen below.

Another issue with Aleta S2C is that its slowest shutter speed is not very slow (up to 4 seconds, as of firmware 1.03.37), which forces it to use higher ISOs in low light.  This is partly mitigated by a night WDR mode (see below), which can increase the dynamic range of high ISO shots.  However, a future update will extend the shutter speed limit significantly.

Aleta can also be vulnerable to flare under some circumstances, and there is some visible chromatic aberration.

WDR Sample Photos

In August 2018, Ultracker added a WDR (wide dynamic range) mode.  Although WDR and HDR both increase the dynamic range, WDR is different from HDR in that WDR uses only a single photo, whereas HDR uses multiple exposures.  WDR takes two exposures and fuses them into a single photo. Here is a cropped photo showing the dramatic difference with and without WDR:

Aleta S2C WDR increases dynamic range
Aleta S2C WDR increases dynamic range

Here are the 360 photos showing WDR.  First, a photo without WDR:

Here is a photo with WDR:

There is also a separate Night WDR mode for low light:

Ultracker Aleta S2C low light WDR mode
Ultracker Aleta S2C low light WDR mode

Although the WDR mode does increase the dynamic range significantly, the result appears to too artificial in my opinion.  Rather, to get the best quality from the Aleta S2C, it is necessary to use the HDR mode (see below).

Aleta S2C AEB mode (formerly HDR mode)

Aleta S2C’s HDR mode is actually an exposure bracketing mode.  It takes three exposures at -2EV, 0EV and +3EV.  The three exposures are stitched identically and saved into one folder.  Here is a sample with firmware 1.03.37, fused with Photomatix Pro:

With decent HDR software, you can get much better results from the “HDR” exposure bracketing mode than the WDR mode.

Firmware 1.04

Firmware 1.04 improves the stitching and enables a slower shutter speed for night HDR mode.    You can download firmware 1.04 here.  See instructions below on how to update the firmware.

Stitching in small spaces is generally more challenging for many 360 cameras.  Here’s a bathroom shot with 1.03:

Here’s the same bathroom shot with 1.04:

The stitching in the nadir has been improved.  Until now, there had been a tendency for the nadir to appear distorted.  The new firmware corrects the distortion:

Aleta firmware 1.04 improves the stitching in the nadir
Aleta firmware 1.04 improves the stitching in the nadir

Note that the toilet bowl in the issue has a slight stitching error, but that is because it was closer to the camera than the minimum stitching distance of around 3 feet.

I also noticed the LED banding is gone, but I don’t know if it just so happened to be the right shutter speed to avoid banding, or if there was some other change that somehow avoids LED banding altogether:

LED banding resolved
LED banding resolved

How to update the firmware

Updating the firmware on the Aleta S2C is simple.

1. First ensure that the battery is charged, or use the AC adapter to plug the Aleta S2C to a power outlet.
2. Copy the firmware zip file to the root directory of a Micro SD card.  Do not unzip the file, and ensure that there are no other zip files in the Micro SD card.
3. Insert the Micro SD into the Aleta S2C and power it on.  After the startup sequence wait around 15 seconds.  You’ll see that the LED display will turn upside down and state, “Firmware updating.”   Allow the firmware to finish updating.  The camera will reboot automatically.

Updating Aleta S2C firmware
When updating Aleta S2C firmware, the LED will be upside down.  This is perfectly normal.

SUMMARY; PRICE and AVAILABILITY (updated: January 11, 2019)

Ultracker Aleta S2 high resolution 12K 360 camera
Ultracker Aleta S2 high resolution 12K 360 camera

Ultracker Aleta S2C has excellent resolution and detail.  When used in exposure bracketing mode (“HDR” mode) with a good third party HDR software, Aleta S2C can produce very good images that are better than any other 360 camera for $1200 or less, as of December 2018.  Indeed, I found it has more detail than even the Insta360 Pro or Insta360 Pro 2 (see this virtual tour camera buying guide and comparison).  At the same time, Aleta has a very fast workflow thanks to its in-camera stitching.  Its bracketed “HDR” photos can also be easily batch processed in Photomatix HDR.

The Aleta S2C does have several downsides to be aware of.  Its stitching is seldom perfect, and you can often see some warping somewhere in the photo.  You also need to mindful of its minimum stitching distance, which is around 3 feet.  There is also noticeable chromatic aberration and flare.  White balance is usually inaccurate, and unfortunately it doesn’t have a true Raw DNG mode.  Finally, it is not very good for low light due to the limited shutter speed (4 secs.).

In summary, I would recommend Aleta S2C for photographers who want to be able to take high resolution photos quickly, and are either able to tolerate some imperfections in stitching, or are willing to repair those imperfections in post processing.  The standard photo mode has very limited dynamic range and the WDR mode has unnatural tone mapping therefore good third-party HDR software is practically a necessity for the Aleta.  The HDR software I’ve been using is Photomatix Pro, which is available for 15% discount using this link and the discount code 360rumors.

Where to buy; Discount

As of January 2019, the price of the Aleta S2C is around $1210 on Amazon with Free Prime shipping.  However, for a limited time, you can get a 20% discount using the code 29R8EDJT . Thank you very much for supporting 360 Rumors at no additional cost to you so I can do more tests and reviews.  Ultracker’s official website is here.

The post Ultracker Aleta S2C Review – high resolution 12K photo (66 megapixel) 360 camera (updated April 26, 2019) appeared first on 360 Rumors.

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