Category Archives: Uncategorized

Service Registration and Cancellation via SMS for Mobile Phone Service in Vietnam

Service Registration and Cancellation via SMS for Mobile Phone Service in Vietnam (Đăng ký hoặc hủy các dịch vụ giá trị gia tăng của điện thoại đi động bằng SMS):

1. Viettel (Customer Service Operator: 1800-8098)

  • Check currently register services (kiểm tra các dịch vụ mất tiền đang đăng ký): 
    • Viettel: SMS “TC” send to 1228
  • 1.2. Roaming (chuyển vùng quốc tế):
    • Register: sms “CVQT” send to 138
    • Cancel roaming: sms “HUY” send to 138  (when receiving confirmation sms, send “DONG Y”).
  • International call (gọi quốc tế):
    • Register: sms “QT ON” send to 133
    • Cancel service: sms “QT OFF” send to 133
  • Miss-call Alert MCA service (Thông báo có cuộc gọi nhỡ):
    • Register basic package: sms “DKC” send to 193
    • Register advanced package: sms “DK” send to 193
    • Cancel service: sms “HUY” send to 193
  • Data service package (3G service – dịch vụ 3G): 
    • Mobile Internet 3G charge: 

Package Name

Subscription   (d/month)

Free usage limit

Limit before changing speed

Fee for exceeded usage



















Unlimited (Không giới hạn)

600MB/month (tháng)




Không giới hạn





Không giới hạn



 (Effective on 16/10/2013)

2. Vinaphone:

  • Check currently register services (kiểm tra các dịch vụ mất tiền đang đăng ký): 
    • Vinaphone: SMS “TK” send to 123

3. Mobifone:

  • Check currently register services (kiểm tra các dịch vụ mất tiền đang đăng ký): 
    • Mobifone: SMS “KT” send to 994

Understanding light: Surface Appearances

Surface Appearances

All surfaces produce diffuse, direct, and polarized reflection in varying degrees. We see all of these reflections, but we are not always conscious of them. That is because of our brain.

Psychological image vs photo-chemical image

The psychological image in the brain may be quite different from the photo-chemical image the eye actually sees. Psychologists have not completely explained why this difference exists. Movement certainly has something to do with it, but not  everything. Some visual defects are less disturbing in a motion picture than they might be in a still photograph, but not much… Photographers know that the brain cannot edit an image of the scene as well as the scene itself. We discovered that fact when we learned how quickly we could spot defects in our images, even though we could not see them at all when we carefully examined the original scene.

When we photographers make a picture we have to consciously do some “editing” onto the “original scene” that other observers do unconsciously.

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SMD LED Brand Comparison

2014 Comments from Functional Utility Inc

CREE and Epistar are the most popular chips/drivers used in the automotive LED light bar industry, although there are actually more than a dozen different brands that are commercially available.

CREE, Inc. was established in 1987 and is based in the USA. They hold thousands of patents in more than twenty countries around the world and are universally accepted as the LED industry’s most prolific innovators. CREE makes the best LEDs, but other manufacturers are in a close second place when it comes to LED quality. Epistar Inc. (a Taiwan based company) and Nichia Corp (a Japan based company) produce good quality LEDs as well. It is important to note that CREE licenses the use of its patents to others, and all three of the leading LED companies manufacture most of their LEDs in China.

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How to use the RAW file on Git2?

Convert RAW file into DNG for Action Camera GIT2?

(For Windows only – as of 2016/05)
How to use the RAW file on Git2?

Thanks to the DashCamTalk member @the-force who helped us to provide this tool and script.

First turn on the RAW option in the Photo mode settings. It will take much more time to save the .JPG and .RAW file after enabled the RAW option.

Convert the RAW file to DNG

RAW2DNG tool:

This tool can support for both 16:9 and 4:3 raw images. Just drag and drop the Raw files in the program, select proper image format and click on convert.

Correct the DNG file

There is much red in original DNG file, below tool is for correcting black level, white level and white balance.

To use the correction tool, simply drag and drop the dng files (also multiple files at once) on the fix_levels.bat. Please note that the exiftool.exe has to be in the same folder as the batch file. The dng files will then be corrected and replaced automatically.

The correcting tool is not perfect, maybe some other Git2 users can help to improve it.

Below fixing DNG script is provided by @Nigel.

exiftool -BlackLevel=200 -WhiteLevel=4095 -AsShotNeutral=”0.5100 1 0.6400″ %1 -overwrite_original

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Understanding light: 3 key principles of light

Three key principles of light:

  1. The effective size of the light source is the single most important decision in lighting a photograph. It determines what types of shadows are produced and may affect the type of reflection.
  2. Three types of reflections are possible from any surface: diffuse reflection, direct reflection, or glare. They determine why any surface looks the way it does.
  3. Some of these reflections occur only if light strikes the surface from within a limited family of angles. After we decide what type of reflection is important, the family of angles determines where the light should or should not be.

These three principles are statements of physical laws that have not changed since the beginning of the universe. They have nothing to do with style, taste, or fad. Understanding these principles enables us to decide what lights need to be where before we begin to place them.

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