Viltrox AF 28/4.5 (FE): Wide-angle pancake lens

This is my third autofocus lens for the Sony a7c.

The Viltrox AF 28/4.5 (FE). It is a disputed lens, but I found it interesting.

The main attraction of this lens is its size. The lens is very small even for a pancake lens. However, it is an autofocus lens. Moreover, it is an autofocus only lens. There is no possibility of manual focus: no ring at all (not mechanical, not electrical).

Since this is a full frame lens, the 28mm focal length is practical for everyday use. It reminds me of the Ricoh GR, which I like.

The lens is quite slow: f/4.5. I find it tolerable for FF, because the APS-C equivalent is f/3 - not much worse than the f/2.8 of the Ricoh GR. But don't expect fast autofocus in low light.

Unfortunately, f/4.5 is the only aperture. There is no aperture control. The camera displays f/4.5 and cannot change it, even in Av/M modes. For me, this is the main drawback. I would like to be able to use f/8: even two apertures (f/4.5 and f/8) would be enough.

It is funny that there is an octagonal diaphragm imitation:

Is it for better sunstars? I haven't tested  it yet.

What I like most is the slider to use the lens without a cap. It protects the front optical element:

It is very practical! Fast opening/closing and small size.

And, by the way, there is no filter thread.

The lens has 6 elements (2 ED, 2 aspherical) in 6 groups.

(It looks as if the background image of the lens is reversed/mirrored. The largest optical element is actually closest to the camera)

I can compare the Viltrox 28/4.5 with my Samsung pancake lenses: the Samsung NX 30/2 (left) and the Samsung NX 20/2.8 (right).

Of course, the NX 30/2 is optically much better (in my opinion), but it is equivalent to the 45mm (it is not a wide-angle lens). The NX 20/2.8 (equiv. to FF 30/4.2) is optically comparable to the Viltrox 28/4.5.

And what the Sony a7c looks like with the Viltrox 28/4.5:

I like it.

See also related notes:

• Pentax Q 07 11.5/9 Mount Shield Lens (2025-08-21)
• Viltrox AF 28/4.5: Firmware update (PC) (2025-07-21)
• Pentax Q: My experience (2025-03-05)
• Viltrox AF 28/4.5: Firmware update (2025-02-19)
• Viltrox AF 28/4.5: Samples [1] - FF - f/4.5 (2025-02-02)

Image albums:

• Viltrox AF 28/4.5 FE

Jeep Cherokee KJ: ABS/ESP working again

A few months ago I replaced the front right wheel hub. This was due to ABS/ESP trouble codes (C1015, C101C, C101F). This is caused by a broken ABS sensor, but the Iljin front hubs are not compatible with the original OEM sensors.

I chose the Iljin hub again, but this time I bought it as Iljin IJ123040 (instead of SNR R186.29).

The replacement made ABS/ESP work. All wheel signals are in the diagnostic:

See also related notes:

• Jeep Cherokee KJ: OEM front ABS sensor and Iljin hub (2024-08-14)
• Jeep Cherokee KJ: ABS control module and SZ Viewer (2024-08-09)
• Jeep Cherokee KJ: ABS/ESP trouble codes (C1015, C101C, C101F) (2024-07-25)
• Cherokee KJ: электроника и передняя правая ступица (2016-09-16)

Image albums:

• Jeep

Helios-40 85/1.5: Samples [2] - FF - f/1.5

Camera: Sony a7c (FF, 24MP)

Lens: Helios-40 85/1.5 at f/1.5

Overall, the Helios-40 can be considered a fun lens. However, I am not a fan, so I sold mine in 2024. I would prefer the Carl Zeiss Jena Biotar 75mm f/1.5, but it is so overpriced. Maybe take a look at the TTArtisan 75/1.5? Not today.

See also related notes:

• Гелиос-40 (85/1.5) и бленда (2022-05-14)

Image albums:

• Helios-40 85/1.5

Twin Peaks Theme on Piano ( Falling + Laura Palmer's Theme )

https://www.youtube.com/watch?v=wEVbkWjeSBM

VirtualBox and Nvidia drivers (Windows 10)

I use VirtualBox on Windows 10 to run Linux and older Windows in guest VMs.

One day, the VMs started crashing. At first I didn't see the dependency (it was some software and hardware changes before), but then I remembered that I had updated the driver for my NVidia GT710 graphics card. 

There is a recommendation to disable 3D acceleration in guests, but that didn't help. I temporarily replaced the GT710 with an AMD HD 7770. Now the VMs no longer crash.

So the Nvidia driver broke VirtualBox in Windows 10.

See also related notes:

• Old graphics card for Gyroflow [RX480] (2025-01-26)

Cannondale Cujo 1 (2018): OEM (WTB) saddle troubles

When I started riding my Cannondale Cujo 1 (2018), I noticed that my pants were wearing out and tearing at a higher rate.

The tear looks like this:

I think it is because of the grooves on the saddle (OEM WTB).

The grooves are notches with sharp edges. They act like the teeth of a file. Note that the tear is higher on the right side.

I decided to replace the saddle to save the following pants.

See also related notes:

• Seido Origin CrMo 144 (bike saddle) (2025-04-17)

Image albums:

• Bicycle

RockStar/AstrHori 35/1.8: Samples [2] - FF - f/1.8

Camera: Sony a7c (FF, 24MP)

Lens: RockStar/AstrHori 35/1.8 at f/1.8

The lens could be very interesting for me, but unfortunately the color rendition is very poor. It is very difficult to get natural colors, at least with my Sony a7c. Could this be a lens for black and white photography? 

See also related notes:

• RockStar/AstrHori 35/1.8 (Sony FE/E): Full-frame lens (2024-03-06)

Image albums:

• RockStar/AstrHori 35/1.8

Zorki-6: Rangefinder film camera (another copy)

The Zorki-6 is obviously not a great rangefinder camera. But it is simple and quite reliable for a camera from the USSR. The main problem is the age of the copies. The Zorki-6 cameras were made in the years 1959-1966: about 60 years ago. Being a cheap camera, it's often not well maintained.

My first copy had some shutter problems, so I returned it to the seller. And in 2024 I bought another one:

This copy is much better. It works pretty well. As I recommended, it is the 1964-1966 version.

See also related notes:

• Zenit-S: film SLR camera (2025-03-31)
• Zarya: Scale focus film camera with interchangeable lenses (2025-01-28)

Image albums:

• Photographic film

SZ Viewer W1-2025-01-08 (Windows), L1-2025-01-08 (Linux)

SZ Viewer (Windows, Linux) changes:

1. Support for D16A engine control module 33980-55P2*/33920-55P0 (1.6 DDiS diesel engine of FIAT origin).

See also related notes:

• SZ Viewer: общая информация (2014-02-15)

SZ Viewer A1-2025-01-07 (Android)

SZ Viewer (Android) changes:

1. Support for D16A engine control module 33980-55P2*/33920-55P0 (1.6 DDiS diesel engine of FIAT origin).

See also related notes:

• SZ Viewer: общая информация (2014-02-15)

Thuraya-4 launched

Thuraya-4 has launched yesterday

https://news.satnews.com/2025/01/03/spacexs-falcon-9-sends-up-thuraya-4-for-the-first-launch-of-the-new-year/

===

SpaceX’s Falcon 9 sends up Thuraya 4 for the first launch of the new year

Success for SpaceX as Falcon 9 launched the Space42 Thuraya 4 mission to a geosynchronous transfer orbit from Space Launch Complex 40 (SLC-40) at Cape Canaveral Space Force Station in Florida at 8:27 p.m. ET. This was the first launch for Falcon 9 in the new year, and was the 20th flight and recovery for this Falcon 9 first stage booster, and SpaceX’s 341st recovery of an orbital-class rocket.

===

See also related notes:

• Thuraya (2024 state) (2024-12-08)

Image albums:

• Mobile

Risespray 11/2.8 Fisheye: Samples [3] - FF - f/2.8

Camera: Sony a7c (FF, 24MP)
Lens: Risespray 11/2.8 at f/2.8

See also related notes:

• Risespray 11/2.8 Fisheye (for full-frame mirrorless cameras) (2023-08-14)

Image albums:

• Risespray 11/2.8 Fisheye

R.I.P. SZ Viewer A1

I have decided to stop releasing the Android version of SZ Viewer (SZ Viewer A1) to the public after February 2025.

Currently, I distribute SZ Viewer A1 only through Google Play.  However, I don't want to verify my developer account as required by Google because it asks for too much personal information to be displayed to users. So my developer account will be removed after 27 February 2025.

At the same time, I have no plans to distribute SZ Viewer A1 as public APK files.

I might release a version of SZ Viewer A1 (in Google Play) before the deadline. But I am not sure. I'm very tired of SZ Viewer after 11 years: I spent a lot of time and resources with no profit and no prospects. It's time to get rid of the dead weight.

See also related notes:

• SZ Viewer A1: That's all Folks (2025-02-27)
• Nokia 5.3 (2025-01) (2025-01-29)

Image albums:

• Internet

Gyroflow v1.6: Important update for Sony cameras

The new v1.6 of Gyroflow offers very important features for Sony cameras (including my Sony a7c):

1. It supports IBIS data and lens profiles. So it is possible to record video with IBIS enabled and stabilize it with Gyroflow. Previously, you had to turn off IBIS to work with Gyroflow.

I have already tested it and it works fine. But the preview in Gyroflow with IBIS enabled video is much worse than the rendered result! There is a lot of jitter in the preview that is not present in the result. As far as I understand, the preview doesn't take into account the sensor movements made by IBIS. Anyway, this is a great feature.

2. Gyroflow automatically sets the frame readout time, which is important for rolling shutter correction. At least for the Sony a7c, Gyroflow uses values very close to my measurements.

See also related notes:

• Sony a7c: Three years with the camera (2025-02-06)
• Old graphics card for Gyroflow [RX480] (2025-01-26)

Image albums:

• Video

Scala+Gradle: AMD Ryzen 7 PRO 3700 vs 5700X

Scala+Gradle: AMD Ryzen 7 PRO 3700 vs 5700X

My other CPU comparison: AMD Ryzen 7 PRO 3700 (very similar to 3700X, Zen 2 based, 8 cores, 3.6/4.4GHz) vs AMD Ryzen 7 5700X (Zen 3 based, 8 cores, 3.4/4.6GHz). The previous comparison was done in the raw image processing program ART.

This time I compared the build time of a Scala project using Gradle (64-bit Java 1.8.0_221). The project is not too big, but it uses macros which slow down the build a lot.

Source lines of code (without blank and comment, calculated with cloc):

Java: 71653 (most of them auto-generated)

Scala: 39151

Java: Oracle JDK 1.8.0_221 (64-bit Server VM)

Scala: 3.3.3

Gradle: 8.11.1

Build time (best result of several attempts):

AMD Ryzen 7 PRO 3700: 55-56 seconds

AMD Ryzen 7 5700X: 49-50 seconds

The performance gain is again around 14-15%.

See also related notes:

• DDR4 3000 vs DDR4 3600 (2025-02-11)

Image albums:

• PC

Pentax K 55/1.8: Samples [2] - FF - f/1.8

Camera: Sony a7c (FF, 24MP)

Lens:  Pentax K 55/1.8 at f/1.8

See also related notes:

• Pentax K 55/1.8 vs Pentax A 50/1.7 (2023-10-07)

Image albums:

• Pentax K 55/1.8

Thuraya (2024 state)

At the beginning of 2024, there were two operational Thuraya satellites: Thuraya-2 and Thuraya-3. Unfortunately, the Thuraya-3 satellite was out of service in the spring of 2024. Today, only Thuraya-2 is operational.

This is very bad for Thuraya users in the eastern and northeastern regions. While Thuraya has tried to reconfigure the network to force Thuraya-2 to work in these regions, the network connection may be very poor (SMS only) or non-existent due to the low elevation angle (<10-20°) of the satellite.

You can estimate the actual elevation angle and direction to the Thuraya-2 in your location on the service: https://www.n2yo.com/?s=27825

The launch of the new Thuraya-4 satellite is planned for December 2024. However, the Thuraya-4 is intended to replace the Thuraya-2, so it is not clear if and how soon it will help improve connectivity in the affected regions.

See also related notes:

• Thuraya-4 launched (2025-01-05)

SZ Viewer W1-2024-12-07 (Windows), L1-2024-12-07 (Linux)

SZ Viewer (Windows, Linux) changes:

1. Added support for some modules (D13A engine,  ABS/ESP control module 52129438AC).

2. Minor UI changes.

Note that version for macOS is discontinued.

See also related notes:

• SZ Viewer: общая информация (2014-02-15)

Scala 3: How to disable significant indentation (Gradle)

Overall, I like the changes in Scala 3. Most of them are actually simplify Scala programming. But I hate significant indentation (indentation-based syntax).

Meanwhile, I have become friends with Haskell's indentation-based syntax, but Scala's significant indentation made the syntax very fragile. It is very annoying.

So I disable significant indentation whenever possible. (With Scala 3) I use Gradle instead of sbt. To turn off significant indentation in a Gradle project:

tasks.withType(ScalaCompile) {
    // disable significant indentation
    scalaCompileOptions.additionalParameters = ['-no-indent']
}

Anyway, programming in Scala 3 tends to make me use braces (curly brackets) even more (in a Rust-way).

Pentax M 100/4 Macro: Samples [2] - FF - f/4

Camera: Sony a7c (FF, 24MP)

Lens: Pentax M 100/4 Macro at f/4

See also related notes:

• Pentax M 100/4 Macro (2024-01-01)

Image albums:

• Pentax M 100/4 Macro