Author Archives: janpenguin

About janpenguin

Email: janpenguin [at] riseup [dot] net Every content on the blog is made by Free and Open Source Software in GNU/Linux.

Tamron Zoom Macro 1:2.8 lens test

It’s first time of playing with macro lens. The resolution power is amazing.  I’ll definitely try different settings for the macro shooting. 100% crop of the original 6k image 100% crop of half size of the original image

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How big is the 24M image?

I’m still learning about features of Sony A6000.  Shooting in raw mode creates about 24M bytes of ARW files. The image size is 6000 x 3346. Large format of JPEG file has the same size. My new HP monitor has … Continue reading

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Blue flower, a cat, and a dog

f/8, 0.0050(1/200), ISO 100 f/8, 0.0003(1/4000), ISO 100 f/8, 0.0004(1/2500), ISO 100 Level adjustment is done by GIMP.

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I got a 105 mm f/2.8 prime lens

The lens is ASAHI PENTAX TAKUMAR 105mm f/2.8, M42 mount. I bought it from an eBay seller in Japan. 24M Mar 11 09:40 DSC00374.ARW 28M Mar 11 09:56 DSC00374.png 35M Mar 11 10:55 DSC00374-M.png I created a 6k (6024×4024) image … Continue reading

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How to change default menu in Grub2

Hibernation and resume resets the default menu.  Below method does not work. When the system boots, grub show the boot menu. Debian GNU/Linux Advanced options for Debian GNU/Linux Select Advanced options for Debian GNU/Linux shows six submenus. Debian GNU/Linux, with … Continue reading

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Windows outperforms Linux in OpenSCAD?

Hmm… it’s very interesting! Should I change the title? Result of Devuan 64 bit system: AMD FX-6100, 8 G memory, Radeon 3000 OpenSCAD version 2017.02.11.nightly 2/13/2017 I built a graphic workstation lately: – Intel Core i5, Skylake – DDR4 32G … Continue reading

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Steel Fisher v1.5 is coming

I used Original Prusa i3 MK2 to print ABS parts. All printed ABS parts Replaced 12 balls Latest firmware: ReprapFirmware dc42 1.17d , DuetWebControl 1.14 Duet Web Control 1.14 It now monitors CPU temperature.  During print the CPU temperature stayes  … Continue reading

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