Updating Thecus n5550 NAS to report over 3GB of RAM

Out of the box, the Thecus N5550 NAS will only report that 3GB is available, even if you have 4GB or more of RAM installed. Apparently, this is due to the N5550 reserving 1 GB for the Local Display Module, which is used to administer the NAS using an external monitor rather than by the web server. The Thecus N5550 forums have some additional details about this. If like me, you do not require the Local Display Module, you can disable the effects of this memory reserve by updating the kernel boot arguments on the N550.

NOTE: Updating boot arguments can seriously harm you NAS is done incorrectly. I take no responsibility if your system is harmed, or you lose data. Make backups of your data before any risky updates. You've been warned. 

Updating the kernel boot arguments requires root SSH access to your NAS. To enable this, go to Home > Network Service > SSH and enable the SSH Service. Next open up a terminal and SSH into the N5550 using the root user. The root password should be the same as the password for the admin user in the web server.

camille:~ astro$ ssh root@10.0.0.120

root@10.0.0.120's password: 

Note:

    Please do not delete or modify any files or folders or it may result in system operation abnormal.

holly:~#

Next, mount the boot partition of the NAS.

holly:~# mount /dev/sdaaa1 /boot

holly:~# ls -al /boot

drwxr-xr-x    4 root     root          1024 Jun  5  2013 ./

drwxr-xr-x   26 root     root          1024 Feb  3 21:08 ../

drwxr-xr-x    3 root     root          1024 Nov 20 23:39 boot/

drwx------    2 root     root         12288 Jun  5  2013 lost+found/

holly:~# 

Now open up /boot/boot/grub/menu.lst using vi.

holly:~# vi /boot/boot/grub/menu.lst 

You should see something like the following:

default=0                                                                                                                

timeout=0                                                                                                                

hiddenmenu                                                                                                               

title Normal                                                                                                             

    root(hd0,0)                                                                                                          

        kernel (hd0,0)/boot/bzImage ro root=/dev/ram0 max_loop=210 console=ttyS1,115200n8 mem=4G video=LVDS-1:d          

        initrd (hd0,0)/boot/ramdisk                                                                                      

title Backup                                                                                                             

    root(hd1,0)                                                                                                          

    kernel (hd1,0)/boot/bzImage ro root=/dev/ram0 max_loop=210 console=ttyS1,115200n8 domb                               

    initrd (hd1,0)/boot/ramdisk                                                                                          

~                                                                                                                        

~                                                                                                                        

~                                                                                                                        

- /boot/boot/grub/menu.lst [Modified] 6/11 54%

Do a quick search about using vi if you are not familiar with using it (I personally use GNU Emacs), but you should be able to move to using the arrow keys, and press i to enter insertion mode (editing). Remove the text that says mem=4G, and save the file and quit by hitting escape then : (colon), and wq! .

Now exit your SSH session.

holly:~# exit

logout

Connection to 10.0.0.120 closed.

camille:~ astro$ 

Disable SSH access to your N5550 by going to Network Service > SSH, and reboot your NAS by going to Home > System Management > Power Management and select Reboot. When your N5550 has rebooted, you should see 4GB (4003MB) of RAM reported under Home > System Information > Hardware Information.

Cheers,

Astro Weasel

Formatting SD card as FAT16 under Mac OS X

I recently purchased a Columbus V990 GPS logger so that I could geo tag my photos. The V990 supports 4GB SD cards. Interestingly, it can read SDHC cards, which would seems to imply that it should be able to support up to 32GB. After digging a bit deeper into the specifications, the limiting factor is due to the V990 supporting only FAT16 file system formats.

The Disk Utility GUI in Mac OS X cannot format SD cards with FAT16. Only FAT32 appears to be supported. In order to format a card as FAT16, you will need to use the command line version of Disk Utility, diskutil, and the BSD command line tool newfs_msdos.

The first step is to get the SD card mounted, which usually involves inserting it in your card reader. Once this is done, you will need to find out the device name that is assigned to card. So run the following on the command line:

bash-3.2$ diskutil list

/dev/disk0

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:      GUID_partition_scheme                        *1.0 TB     disk0

   1:                        EFI EFI                     209.7 MB   disk0s1

   2:                  Apple_HFS Macintosh HD            999.3 GB   disk0s2

   3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3

/dev/disk3

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:     FDisk_partition_scheme                        *8.0 GB     disk3

   1:                 DOS_FAT_32 GPS_LOGS                8.0 GB     disk3s1

In my case, the SD card is at /dev/disk3. Now we just need unmount the device:

bash-3.2$ diskutil unmountDisk /dev/disk3

Unmount of all volumes on disk3 was successful

The next step is to run newfs_msdos and indicate that we want to create a FAT16 filesystem:

bash-3.2$ sudo newfs_msdos -F 16 /dev/disk3

newfs_msdos: warning: /dev/disk3 is not a character device

512 bytes per physical sector

newfs_msdos: warning: sectors/FAT limits sectors to 4194721, clusters to 65534

newfs_msdos: warning: FAT type limits file system to 4194144 sectors

/dev/disk3: 4193536 sectors in 65524 FAT16 clusters (32768 bytes/cluster)

bps=512 spc=64 res=1 nft=2 rde=512 mid=0xf0 spf=256 spt=32 hds=255 hid=0 drv=0x00 bsec=4194144

After remounting the SD card, you will notice that the capacity is only 2GB, a bit short of what the V990 is supposed to support. In order to increase the capacity to 4GB, we need to increase the number sectors per cluster to 128: 

bash-3.2$ sudo newfs_msdos -F 16 -c 128 -e 1024 /dev/disk3

newfs_msdos: warning: /dev/disk3 is not a character device

512 bytes per physical sector

newfs_msdos: warning: sectors/FAT limits sectors to 8388929, clusters to 65534

newfs_msdos: warning: FAT type limits file system to 8387776 sectors

/dev/disk3: 8387072 sectors in 65524 FAT16 clusters (65536 bytes/cluster)

bps=512 spc=128 res=1 nft=2 rde=1024 mid=0xf0 spf=256 spt=32 hds=255 hid=0 drv=0x00 bsec=8387776

This gives us a 4.29GB FAT16 filesystem, with 1024 files per directory, which is useable by the V990.

VR Light Leaks with Nikon 24-85mm AF-S

There are two main advantages to taking star trail photographs during the winter: 

1. The air is colder, which can result in clearer skies. 
2. The sun sets much earlier. Often as early as 4:00pm for me. Taking photographs is a far easier endeavour in comparison to the summer when the sun sets at 9:00pm and good exposures are only possible after 12:00am.

There are two main disadvantages to taking star trail photos during the winter:

1. The air is colder and it can get down right freezing!
2. Winter often brings more precipitation, which results in more clouds, which results in less stars.

During a recent trip to Harrison Hot Springs, I was lucky enough have clear skies. So I took the opportunity to photograph the stars. My setup was a Nikon D600 with the Nikkor 24-85mm AF-S lens. After taking some initial test shots, I noticed a light leak at the bottom and lefthand side of the frame: 

Harrison Lake, facing North (24mm, f/3.5, 30sec)

With my DK-5 finder on, I initially thought that the leaks might be the artificial lights that were to my left and right.  I placed my lens hood on, but still observed the same amount of light leaking into the 24-85mm. I decided to recomposed, just to see if something would change:

Harrison Lake, facing NNW (24mm, f/3.5, 15sec)

Same amount of light leak, and in the same location in the frame. I tried various things, including using my toque to cover up various parts of the camera and lens.  After about an hour, clouds were beginning to approach, so I decided to use my 35mm 1.8 AF-S (DX, not the new FX version) to salvage what I could of the evening. 

When I moved to a warmer location, I spent some time experimenting with the Nikkor 25-85mm to see what was going on. I had used this lens for star trail photography before, so these light leaks were a bit of a surprise. I tried various experiments, including placing the lens cap on the lens and taking the exposure in a light-tight box, but I would continually get something like the following:

Light leak with lens cap on (f/3.5, 30sec)

This was very odd, considering that the surrounding light was changing during my tests, but the light leak remained the same. I suspected that the focus window on the lens was leaking light, and I even used a flashlight to help track down the leak on the camera/lens, but again, the exposure remained the same. The only thing that caused the light leak to change was zooming the focal length to 85mm:

Light leak at 85mm (f/4.5, 30sec)

Since the light leak always remained the same, all I could think of was that the camera itself was generating some kind of light internally (the view screen? the status LED? the LCD screen?). After doing some in-depth searching on the web, I came across a post on Luminous Landscape where someone theorized that the VR in lenses might be using lasers. I turned off the VR and voila, the light leak was gone:

Light leak gone! (24mm, f/3.5, 30sec)

I felt silly that my VR turned on the entire time, considering that I shouldn't have had VR turned on when my camera in mounted on a tripod! Time to create a preparatory "checklist" for my star trail photography. For those that are interested, here's a photograph taken with the 35mm 1.8 AF-S on the D600:

Nikon D600 with the 35mm f/1.8 AF-S (f/8, 30min)

Cheers!

Verified. Nikon D600 does not light leak on long exposures

It is fully confirmed: My Nikon D600 does not light leak on long exposures. During a to Bromley Rock Provincal Park near Princeton BC, I took a 30 minute exposure of the night sky and the Similkameen River. A near full moon shining on the viewer finder and but no light leaks. Excellent results! The supplied Nikon DK-5 is the key.

Star Trails and Moonlight at Bromley Rock

Star Trail Light Leaks with Nikon D600

One of my favourite subjects for photography is star trails. On a recent trip to Martha Creek near Revelstoke, I was disappointed with some of the results I was achieving with my Nikon D600, especially given that the exposures were 8 minutes in length:

Minor Light Leak at Martha Creek

I had much better success with my Nikon D90 in earlier shots:

Milky Way At Lac Le Jeune

Initially I thought this was being caused by the fire or small lights in my campsite. I made adjustments, and faithfully re-composed to a different location and attempted a 30 minute exposure. The results were very disappointing to say the least:

Major Light Leak at Martha Creek

I began to question the usefulness of a D600 in one of my favourite styles of photography, and was considering calling Nikon support to report the issue. But before doing so, I did a quick search on Google and observed results that were similar. 

After digging further on various forums, I concluded that I might have had light leaking through the viewfinder of the D600 , which was odd considering I had not had this problem with the Nikon D90 . I did some quick experiments using my Cokin IR and Cokin ND filters during daylight conditions:

Cokin IR Filter - Light Leaks

Cokin ND8, ND6, & ND4 Filters Stacked - Light Leaks

Light Leaks! After adding the Nikon DK-5  to the viewfinder of the Nikon D600  (you know, that small piece of plastic that your camera came with, but you didn't know to do with!), I was pleased with the results:

Cokin IR Filter - No Light Leaks

Cokin ND8, ND6, & ND4 - No Light Leaks

I have not yet tested this in a star trail scenario, but I am quite confident about what I was observing, and relieved that my decision to move to a D600 was not a bad one.

Cheers!