View on GitHub

Quorten Blog 1

First blog for all Quorten's blog-like writings

KEH Camera, and the fate of National Camera Exchange

quorten

2020-09-21

Categories: pentax-k-1-camera   covid19  
Tags: pentax-k-1-camera   covid19  

KEH Camera, that’s a new name to me, but it’s where I bought my replacement used Pentax AF200T flash box. Sure they pride themselves in being mainly an online store, but where are they located in? Georgia, oh okay, that’s a great location to be in for international shipping.

20200921/https://www.keh.com/shop
20200921/https://www.keh.com/shop/about-us

Interesting blog article about spending more on a camera body versus spending more on a lens. If you’re a skilled photographer, spending more on a DSLR camera body can pay off, but less skilled photographers are generally recommended to go cheap on the body and expensive on the lens. For film, cheap camera bodies can perform fine in terms of quality, really it comes down to skilled use of the lens and the film type.

20200921/https://www.keh.com/blog/should-you-spend-more-on-a-camera-or-spend-more-on-lenses

Read on →

Wow, Amiga community argument resulted in unauthorized board clone

quorten

2020-09-20

Categories: raspberry-pi  
Tags: raspberry-pi  

End of all TF (Amiga) projects because of a TF536 unauthorized clone. Wow, this is a really interesting happenstance.

The boards got cloned following an argument in the forums. Some other folks thinking they’ve been being cheated and wanted to “teach a lesson,” so to speak. They were otherwise scheduled to be released as open-source February of next year, but that plan got canceled and instead a copyright infringement lawsuit is being pursued instead.

And wow, how the community themselves comments how they sometimes try to fight each other when they should really be trying to help each other.

20200919/https://www.exxoshost.co.uk/forum/viewtopic.php?f=65&t=3359

My process to migrate a disk image from hard disk drive to SSD

quorten

2020-09-19

Categories: unix  
Tags: unix  

I had one laptop where it was suspected that there may be hardware issues on the computer. The laptop still had a spinning disk hard drive in it that was planned to be replaced with an SSD, but procrastination pushed that timeline back further than hoped for. Normally I’d just power on the laptop housing the hard disk drive, boot to GNU/Linux, and use network copies to assist. But, finally getting around to doing this on a late timeline, I had to be extra cautious compared to normal and take a few extra steps.

So, the plan for archiving the hard disk drive.

I will do a “jukebox copy,” copy in four segments at a time, each 190 GiB.

190 * 4 = 760 GiB

That’s more than the approximately 640 GiB on the hard disk drive. Each segment copies to the internal laptop SSD, then we copy to the 6 TB hard drive, accessed via an external USB hard drive enclosure. That’s where we do the final reassembly. For the sake of safety, each segment will go to a separate file, then I’ll copy to a final combined file once done.

So, that comes down to using 4 dd command lines, as folows.

PLEASE NOTE: Make sure to terminate gvfs-udisks2-volume-monitor while doing source disk copies. You don’t want your disks auto-mounted and modified when they haven’t been completely copied!

Read on →

Using `gparted` on a loop device disk image file

quorten

2020-09-19

Categories: unix  
Tags: unix  

So, you have a disk image file, and you want to make some partition modifications to prep it before copying to a new hard drive or SSD of a similar but slightly different size. How do you do that? It’s actually very easy, if I just give your the commands.

sudo losetup -P /dev/loop0 disk1.img
sudo gparted /dev/loop0

So, what does this mean? First of all, gparted can take a device file, so even though it won’t iterate loop device files by default, you can ask it to operate on loop device files specifically. Second, you can specify the -P option to force the kernel to create partition device files for each partition in the loop-mounted disk image. I should have known this one earlier, this is a much easier way to loop-mount partitions from a disk image file.

partprobe can be used to refresh the partition table and partition device files for physical drives, but it doesn’t work for loop devices.

Read on →

My first encounter with wearing down a SLR camera flash tube to the end of its life

quorten

2020-09-19

Categories: pentax-k-1-camera  
Tags: pentax-k-1-camera  

So, I’m using my good only SLR camera flash, Pentax AF200T, on my Pentax DSLR camera just as normal, but then as I am in the middle of a shooting session, I notice the flash won’t fire. Batteries low? I check the flash charge status, it says its ready. But the camera won’t fire it. Camera fuse disabled it? I try restarting the camera. No dice. I look at the flash box, it was facing away from me on a separate tripod stand. The ready light is on, so I press the test button. Nothing happens. Maybe it needs new batteries because firing requires a certain voltage threshold?

Okay, so I change the batteries, and okay, it’s working again. I take several more photos, but then it stops working.

Okay, so it’s real, the flash can wear out like this, and that’s part of the reason for the test button. Dang, or maybe it’s just stressed this one time?

Here, they say the bulb is broken, send it in to the manufacturer for repairs. Okay, dang, no can do with a vintage flash box then.

DuckDuckGo slr flash ready but test button won’t fire
https://community.usa.canon.com/t5/Speedlites/My-speedlite-600-ex-rt-will-turn-on-but-it-won-t-fire-Any/td-p/114765

Read on →

COVID-19 several months into the pandemic

quorten

2020-09-18

Categories: covid19  
Tags: covid19  

Here is an interesting article on what we know about COVID-19 after this much time into the pandemic. The main thing I think is interesting, COVID-19 isn’t that strong of a virus. Not just in terms of the fact that it tends not to kill its host upon infection (and hence its successful spread), but the fact that the virus, when exposed to the environment, tends to get damaged and loose its viral effectiveness quite easily. Really, the only thing that enables its spread is close human contact, especially breathing the same air from another person. And, of course, airplane transit of humans is what facilitated its international spread.

https://elemental.medium.com/the-most-likely-way-youll-get-infected-with-covid-19-30430384e5a5

Embedding fuse bits in compiled AVR output, high-voltage serial programming

quorten

2020-09-17

Categories: raspberry-pi  
Tags: raspberry-pi  

Is it possible to embed AVR fuse bit values inside a compiled C source file for programming? Indeed it is. However, be forewarned that getting this into avrdude is not as straightforward as you may like. Essentially, you’re going to have to extract the .fuse section and pass in the value in a separate command.

20200917/DuckDuckGo avr-gcc fuse bits
20200917/http://www.nongnu.org/avr-libc//user-manual/group__avr__fuse.html
20200917/DuckDuckGo avr-gcc avr dude fuse section
20200917/https://www.avrfreaks.net/forum/fuse-bits-c-source-avr-libc-and-program-avrdude

How do you do high-voltage serial programming for the ATTiny85? Easy, just build this circuit with Arduino, or a slight variant with more level shifters Raspberry Pi. The solution is rather simple, just use a BJT transistor to control the 12 V signal. Please note that 1K resistors are used on all Arduino outputs, probably to protect the Arduino from any unexpectedly high voltages. A 1K resistor is also used in the 12 V power supply path, to limit the amount of 12 V current that can flow.

The Arduino sketch, in particular, just resets the fuse bits so that you can use standard In-System Programming (ISP) over SPI to write the rest of the program code. avrdude does have high-voltage serial programming modes in it, but I’m not sure how to use those with Raspberry Pi.

Read on →

MacSD, another SCSI to SD device, and others

quorten

2020-09-15

Categories: mac-classic  
Tags: mac-classic  

Interesting, there’s another SCSI to SD device out and about called MacSD. It’s rather elusive from its site, hasn’t been much discussion of development of it from its original author so it seems. But it does emulate CD audio.

20200915/https://68kmla.org/forums/index.php?app=forums&module=forums&controller=topic&id=60732&tab=comments#comment-650620
20200915/http://macsd.com/

Also, there’s also some other Arduino-based devices.

20200915/https://hackaday.com/2016/12/25/the-tiny-scsi-emulator/
20200915/https://bitbucket.org/tinyscsi/tinyscsiemulator/src/master/
20200915/https://github.com/ztto/ArdSCSino-stm32/blob/master/ArdSCSinoV2.png

Finally, a random article. Restoring multiple Commodore 64 devices at once.

20200915/https://hackaday.com/2016/08/07/detailed-log-of-commodore-64-refurbishing/