Showing posts with label biased web. Show all posts
Showing posts with label biased web. Show all posts

Sunday, June 17, 2018

answer--not physically destroy hdd, for erase data from a hard disk so no one can ever recover it.


Thinking about selling used hard drives.

Recently I bought external 2.5" hard disk drive because my external 2.5" hard drivers have low on free space. Copied all the data to new hard drive from old hard drives.
Now I have number of hard drivers--external 2.5" 500GB, 750GB and a few desktop PC 3.5" hard disks that no use. So I'm thinking about to sell it.

Before I'm selling, I needed to clean up the hard disk so no one can recover my personal data. I don't much have important data though--I have a lot of piece of writings and ideas. But I don't think people will understand what those a pieces of writing is for.
I know this because some of those ideas, I already wrote in my twitter or blogs but no one seems to understand what I am saying. So I don't much care about those.
But I have been learning photography so I have tons of photos which I'd like to erase it.

So I did googling and came across this--in Quora:
How do I erase data from a hard disk so no one can ever recover it? 


Why would you like to physically destroy hard disk which you spend a lot of money for?

Quite surprise to see so many answered with physically destroy the hard drive.

I thought -
Wow...wows!
Nowadays, everyone is sooo rich that everyone suggest to physically drilling, shredding the hard disk.
I'm not rich so I had to completely erase the data before selling.


I know the simple solution without physically destroying it.

I know how software works--because I was a programmer. So I know very easy and simple way. Download some software--bigger size will be better, useless documents or anything from the internet or your not important things like Netflix movie files. And delete all your data. And then copy the downloaded software, documents and all. And kept copy it(same files over and over--make folder to more easier--Windows will make new name for it like below screenshot) until hard disk became zero-ish byte of free space.
screenshot: overwrite files for make unrecoverable

So when the recovery software or professional try to store data from my hard drive, they will only recover those useless data.
It's THAT simple to permanently erase data.
Yes, it takes time. But it perfectly works.


Yes, someone answered what I suggested--overwrite data to remove personal data.
And someone saying that forensic analyse(or something) still can find a bit of information from there. Sure. That might be true.

That's why my solution makes more sense.

Because my personal data was already replaced by thousands, thousands and thousands of files.
That means forensic analyse take more, more and more time to figure out which bit of information connected to the which part of information. It's like thousands, thousands and thousands of jigsaw puzzles to figure out.
And it will be almost impossible because a lot of pieces were missing.

Loren Forslund answered very interesting one and I think it's very good method, too:
My method is using Ubuntu disks utility to break all partitions down and formatting the drive into one “FAT” partition. Now make 2 equal partitions and format them in EXT4 writing over the drive. Now break these partitions back to one NTFS partition over writing the disk. I’m sure if you had one million dollars worth of DOD equipment and 3 months of time you may get a scrap of something, but I doubt anything useful.


People watched way too much TV shows--CSI kind of TV shows.

Especially this part:
I'm sure if you had one million dollars worth of DOD equipment and 3 months of time you may get a scrap of something, but I doubt anything useful.
 - People were watched way too much TV shows
 - and they were way too much talk about this theoretical ideas.

Let's talk about reality.
I told you that I bought a external 2.5" hard disk which has 4TB space--actual size is 3.63TB.
So I put all my old data to this new hard disk..
screenshot: my external hard disk drive's files and folders

Last time, I had a lot of software and documents from the internet. But when I started taking photos, I had to delete those files because nowadays DSLR or mirrorless camera need bigger space to backup.
And other reason is I can always go online to get those software again.  So I don't need to kept in my hard drive.

So in my case, 50% of files(153,598 / 2 = 76,799 files) were probably personal data. But each photo was like 7 to 24 mega bytes only. I have software, downloaded documents, audiobook from Librivox and games and those were far more bigger size than photos.

So even if I have 50 to 70% of files were personal data(because photos I took), 40 to 80% of space were filled with not personal data. That means 40 to 80% of 0.98 tera byte.

That means if forensic analyse find a bit of information, it will quite likely not my personal data. For example, 70% of space were not personal data means:
other not important things - 1,003.52 giga byte * 70% = 702.464 giga byte
my personal data - 1,003.52 giga byte * 30% = 301.056 giga byte
Because my personal data was only 30% chance to picked up by forensic analyse.


And there has more. I have thousands of photos but do you think all of my photos were all very important photos--which I probably use it in my blog.
Photography is my hobby so technically it wasn't very important data.

Even if so, reality is this:
How many professional photographers really use all of their photos they took, do you think?

And how many people do you think they use their hard drive only for their important data?
Even if that's the case, why do they need 1 to 4 tera bytes of hard disk?

I have important documents but most of my documents(which I kept it in text file format--smaller than Word file format.) takes only a few kilo byte.
So I'm sure that a few giga bytes of hard disk should be enough for their personal--important data.



Reality of un-delete kind of software.

How I know this? Because about 10 or 15 years ago, I tried to recover my important data from un-delete kind of software with no success.
I can see the files with so many other files. But I can't recover it because it was already half destroyed--some new files already overwritten some part of those files.

You've known this, too. Good example is 'corrupted file'. Did you recover that corrupted file?


Reality is this:
Even if that forensic analyse find a bit of byte, what can you do with that part of byte?


It was 10 or 15 years ago experience so I have to check. And found this:
Recovering Deleted Files After Formatting: Is it Possible? | Deleted File RecoveryThere are many debates regarding the possibilities of recovering deleted files among computer scientists. All evidence points to the fact that in order to recover files deleted from recycle bin, or any other part of the operating system, they must not have been written over.

In order to recover a deleted file every sector that included data for that file must be in it’s original condition. Overwriting any part of this file with new data will cause corruption.


As you can see, this professional(??) data recovery company saying things were far different than what many people answered in Quora.
Professional data recovery company saying that they can't recover if it's already written over.
But many people in Quora saying that you can recover it--because you can find a piece of information with forensic analyse(or something). So you must do physically destroy hard drive--drilling, shredding, burning and among other physical way.

See the difference.


Even if you recover the part of file, you probably can't read--because of corrupted. But what many people in Quora saying is it can read--recover it.
* If you seen CSI kind of TV show, they can always recover it, don't they?
Yes, you can recover the random data. But do you think that random data is worth a million dollars with spent a few months or a year of work?



That's why I completely agree with what Loren Forslund said:
I'm sure if you had one million dollars worth of DOD equipment and 3 months of time you may get a scrap of something, but I doubt anything useful.


Reality is extremely different than what people were saying in internet, unfortunately.
This is how people kept getting more wrong ideas.



P.S. I found permanent file delete software:
They also explain same thing--overwrite to make unrecoverable.




Wednesday, June 6, 2018

Nikon 24mm f/2.8 AI-S Nikkor lens sample photos.

Nikon Nikkor 24mm f/2.8 Ai-s lens technical details:

format: 35mm SLR
type: Prime lens

mount type: Nikon F mount
optical design: 9 elements in 9 group
aperture range: f/2.8~f/22
aperture blade: 7
minimum focus: 30 cm
filter thread size: 52mm
weight: 275g
length: 45.7mm

I don't much care about this technical details of lens. But sometimes it can be useful.
For example, if I already have 52mm uv filter or hood, I can use with this lens.
And I'm walking long hours when I do photo-walks. So if lens wasn't heavy, it was very suitable for me. That is the reason that I mostly shoot with prime lens.
So I do check those things from the technical details.


You can read more about the lens from here:



About the lens evaluation:

I'm not that much good at judging about the lens. But I read quite a lot about the lens from the web.
And quite number of times, I'm finding very strange remark--like this one.

I can't say I really like what Nikon 24mm f2.8 ais produce. And I probably can say I really don't like the corner or edge area--but not all the photos I took. So sometimes or many times, it was quite okay with those corner or edge area.
So if some people saying Nikon 24mm f2.8 ais was bad--because she or he doesn't like what Nikon 24mm f2.8 produce, I probably can agree.

But problem is when some people trying to prove Nikon 24mm f2.8 ais lens were terrible lens--with compare the extremely expensive--excellent lens.
Some people compare this lens with Nikon 24-70mm f/2.8 lens--I don't know much about zoom lens but I think this is one of best zoom lens that Nikon produced, or with Nikon 18-35mm f/3.5-4.5G lens.
Nikon 24-70mm f2.8 costs about $1,800. And Nikon 18-35mm costs about $750.

Nikon 24mm f2.8 ais is old lens so compare with market price wasn't fair. But newer version of this lens is Nikon 24mm f2.4d so it costs $339. You can probably buy Nikon 24mm f2.8 ais lens for about $120 to $200.
Many people were trying to compare with these huge different price tag--$1,800 lens to compare with far less than $339 lens.
Does it make sense to you?

At least, they don't try to compare with Nikon 14-24mm f2.8 lens which quite number of people refer to one of best wide angle zoom lens--not only Nikon lens, among other brand lens like Canon.


This lens can't be really good like Nikon 50mm f/1.8 lens or probably like Nikon 28mm f/2.8 Ai-S lens. But I don't think it is worse than 20mm f/2.8d lens--that also quite hard to judge because 20mm was wider than 24mm lens so corner wasn't worse than 24mm.

Nikon 24mm f/2.8 ais probably wasn't great lens like Nikon 50mm f/1.8 or Nikon 28mm f/2.8 Ai-S(minimum focus to 0.2 meter version). But I think it is quite good lens or at least, it's okay lens--not everyone, of course. And many people include me was slightly disappointed with corner--quite soft.
So if you use with crop body, I think you probably won't disappoint--people have different taste of things so some people might disappoint though.


Photos of the lens that I used.
Nikon Nikkor 24mm f/2.8 Ai-s lens

Nikon Nikkor 24mm f/2.8 Ai-s lens



Technical notes:

These photos were all taken with handheld and I used Nikon lens to Sony E mount or Micro four thirds adapter so I have no idea about aperture number for the photo. Some photos were taken with Nikon D7000 which can recorded aperture number.

When I am taking photos, I do use Raw file format. So I need to convert Raw file to jpg file and during that time, I do some post-processing--this is kind of darkroom process in developing film.
And when I do this, I don't use any default setting from Rawtherapee because there has some image modification settings like sharpening, micro-contrast and among other things.
I don't use Adobe Photoshop but this also has same kind of default setting with sharpening.
This isn't important for photography. But this is about the lens--what kind of photo I can take with this lens. So sharpening won't help to know about the lens.

So when I do use Rawtherapee, I removed all the default setting.
I will do these adajustments, if necessary:
 - click the auto button in exposure tab--automatically calculate the exposure value,
 - adjust exposure value, if overall image was still dark or too bright,
 - adjust contrast(between 3 and 18) in L*a*b* adjustments tab,
 - if there have some areas were too dark or too bright which makes me feel unbalance the overall look, adjust the shadow/highlight value.
 - Sometimes, white balance set to auto. Because Sony A7's white balance value was quite terrible when I do use other brand lens--not Sony E mount lens.



Sample photos:

Nikon D7000 with Nikon 24mm f2.8 lens - Nikon D7000 has crop factor of x1.5 so this lens became 36mm lens.

at the Dongdaemun design plaza, Seoul

at the Guinsa Buddhist temple, Danyang
I was trying to focus center part but it came out like that. But you can see how out of focus part looks like--Nikon D7000 has crop factor of x1.5 so Nikon 24mm became 36mm.
With crop body, it is still useful for close up--or macro shot.

Winter in Guinsa - Korean 'sa' means Buddhist temple.
Winter in Guinsa - Korean 'sa' means Buddhist temple. - from my flickr account.


at the Sincheongyo, Daegu
As you can see from the photo, it was mixture of quite bad pollution, smog and not very bright winter sun light.


Olympus E-P3 with Nikon 24mm f2.8 lens - Olympus E-P3 has crop factor of x2 so this is lens became 48mm lens--not wide at all.

at Sincheongyo, Daegu

at Hanja, Cheongdo
P.S. I forgot to mention that this photo was post-processed with Olympus Viewer 3 program. Because I felt that it has some noise--ISO 200 so I didn't use Rawtherapee.



This photo was cropped out from previous photo. I did use auto-white balance function in Gimp--open source software. For making clear the leaves and water droplets.


Sony A7 with Nikon 24mm f2.8 lens:

at Sincheongyo, Daegu

near Chilseongsijang, Daegu
This is handheld-HDR shot which automatically generate from Sony A7--HDR paiting in Picture effect menu. And it took three shots to make one HDR photo.
That is the reason why you can see left side of photos with ghost--halo of cars.
I did include this photo because this photo shows Nikon 24mm f2.8's capability--Sony A7 wasn't crop body like above's.



Three photos were taken at same spot--Sincheongyo. Olympus E-P3's was slight different angle though.
So you can compare the full frame camera with crop body camera--crop factor of x1.5 and x2.



with tilt adapter:

I have a tilt adapter which can capture diorama style photo.
I don't know much about this diorama effect but I'm just showing what it will do with this adapter.

Nikon 24mm f/2.8 with tilt Nikon-Nex adapter
This is Nikon 24mm f/2.8 lens with tilt Nikon to Sony e mount adapter.


snowing town, Daegu

at Sincheon-dunchi, Daegu



P.S. If you'd like to read in Korean, you can read it from here--this is my Korean blog.

Wednesday, March 29, 2017

This is the reality---how Apple fanboy dominated this world. - Reality of web storage service.


I've got photos from friend--

screenshot from Best Of Quora facebook page

I didn't even read whole thing because I know the cost of web storage.

So I wrote in my facebook timeline:
This is the reality---how Apple fanboy dominated this world.
Do you know how much does it cost for 5giga byte storage for internet?
Do you know flickr.com even give you free for about 200 times more size--1 tera byte of hard disk? Of course, they will display the advertisement but it was soo small that you will not even notice it.
Are you living in stone age that you think 5 giga byte of storage were some kind of miracle size?
Go and learn how internet became nowadays.


It wasn't really unlimited storage. And it wasn't started like that.

I was quite strange that Google give unlimited storage because there has limit. What I know is it will reduce the size, that's why I've got only 15 giga byte which isn't free at first, if I'm not mistaken.

Google advertised when you buy the android phone, you will get 15 giga byte of web storage.
I thought that 15 giga byte of web storage was really big about 3 to 5(??) years ago. But actually it wasn't.
Because I'm sharing with all of my google services like email, google docs, drives, photos, videos and even here--my blog service.


See. Actually it wasn't big. Because each product has 3 to 5 giga byte which is almost same as any other service.
For example, wordpress which is same as blogger here, give 3 giga byte of storage. You can read details here-Adding Storage Space — Support — WordPress.com
Other example, dropbox which is same as google drive, give 2 giga byte of storage. You can read details here-How much does Dropbox cost? - Dropbox Help - Dropbox
Onedrive which is same as google drive, give 5 giga byte of storage. You can read details here-Microsoft OneDrive Plans


People--even internet technology news writer, actually don't know why google give 15 giga byte. And they think google gave it for free because it was big.


Some of us know 15 giga byte was actually not big. So does Google.



Unlimited storage but compressed image--that means image quality will loss.

So Google offer the unlimited storage with limited photo size. I probably confused about this but if I'm not mistaken, they reduce the size more than half size if it was even 13 mega pixel. That's why I choose upload photos with original quality. I choose that almost year ago, I think.


Google Photos: Unlimited storage for free, with a few gotchas @ June 1, 2015 By Todd Ogasawara
Google Photo gives you unlimited storage space if you are willing to limit photo resolution to 16 megapixels and video resolution to 1080p. You do have the option to store at higher resolutions, but the storage counts against your Google Drive quota.

But it's not only photo resolution. It will compressed image, too.

Choose the upload size of your photos and videos - Google Photos Help
Photos are compressed to save space. If a photo is larger than 16MP, it will be resized to 16MP.

Or if you can buy a Google Pixel phone, you will get unlimited storage without those limitation. You can read here - Google is giving free, unlimited original-quality photo and video backups with the Pixel phones @ Oct 4, 2016 by Lauren Goode




Wait a sec. So Google only offer that much!?

Facebook, almost everyone using nowadays, right?
I've never seen any limitation of photos. People kept uploading it, don't they?
Yes, reduced photo quality(like Google does or more) and size but they gave almost(??) unlimited size, don't they?

How about Instagram?
Do I heard any limitation about photo uploading?
Yes, reduced photo quality(it wasn't much, I think. More for the size, I guess) and size. But they gave almost(??) unlimited storage, don't they?


How about flickr.com which I mentioned very earlier.
Yes, they offer 1 tera byte of storage.



Do you think do I have to find out all the other websites about the offer? It's enough, right?


See the title of this article. "This is the reality--how Apple fanboy dominated this world."
That's why Quora.com who has best answer. And choose that--Apple fanatic side of story, for the best of quora.



P.S. Slightly different but almost same story - Illogical idea ruled internet--especially social networking sites. @ March 17, 2017 - my other blog.

P.S. (at April 3, 2019): I found this question at quora.com - Why does Google offer unlimited storage for photos via Google Photos app? What's in it for Google?
So many answers include what I mentioned here.
Interesting thing is nobody talked about facebook or instagram. Because I'm sure they know about the websites and very likely using the websites. But they don't even know facebook and instagram gave unlimited photo storage like Google does--I'm sure some of their friends uploaded thousands and thousands of photos.

Saturday, January 25, 2014

Many gadget lovers are living in their own small world.

What a ridiculous idea. If I'm not doing in wedding photography, I am not a professional photographer?

Get out of your narrow-minded world.
He or she was talking like looking down photographers who don't use mention the product. People use product their needs, not by your choice.



No wonder there has movie call the 'The Matrix'.

Thursday, May 12, 2011

How that place was beautiful? I can't see it.

It could be sarcasm but I don't see how that place was beautiful.

Mobypicture user Ancilla Tilia uploaded photo with this: Our shooting location Oudewater is so beautiful! http://moby.to/sjgy4a

I can imagine that house looked pretty but I have absolutely no idea how beautiful that was. Because I've never been there.

Because it doesn't have any natural and real color in it.


So I had to googling about it: oudewater – google image.

And I found this photo which was almost same site: Havenstraat, Oudewater by JohanBakker


I couldn't know why http://moby.to/sjgy4a is beautiful until I found a real photo of place http://static.panoramio.com/photos/original/2494507.jpg.
* This old link doesn't work but you can simply find wikipedia's photo from here.

Can't you see the problem with iPhone?

Saturday, October 9, 2010

Talk about originality of design. It proves how biased mobile tech web and geeks were.


American-based company Apple's Macbook Pro and Nokia N9

Engadget's article Nokia N9: the MacBook Pro Phone @ August 19, 2010 by Thomas Ricker said

What was it that Anssi Vanjoki said? Something like, "If there is something good in the world then we copy with pride."

And most of the people commented about Nokia's copy of design. It was not just a few people because that article has 217 comments.



Here is the truth about copy of design.
Photo taken from Dear Engadget, who is copying who? [updated] @ August 19, 2010 by Engadget Sucks

Seriously. Who is copying who?

So if they were the gadget expert(That is why they were the writer of Engadget, right?), they must know about Sony Vaio notebook computer. But they simply dismiss it.
Or they don't know anything about gadget?



American-based company Motorola's Flipout and Nokia Twist

In contrast, Motorola almost copy the design from Nokia but nobody talks about it.

I've got news from @bperry
amazing how similar the AT&T Motorola Flipout http://bit.ly/9Dcu6u looks to the VZW Nokia Twist http://bit.ly/9hrh7W
Saturday, September 25, 2010 3:34:03 AM via DestroyTwitter 
Photo taken from Engadget's article AT&T-branded Motorola Flipout released… on eBay @ September 24, 2010 By Chris Ziegler

There has 35 comments and almost none of people were talking about similarity of Nokia Twist.

This is a photo of Nokia Twist.
photo taken from Nokia 7705 Twist launched Stateside on Verizon (photo gallery) @ September 10, 2009 By Mike

Engadget's readers really concern about originality of design but strangely they don't even bother about it. Why?