FourEyes Blog

What’s with the noise?

FourEyes — Thu, 17 Jan 2008 11:11:31 +0000

A lot of people associate noise with unwanted sound. Some people like me also call unwanted/unintended/undesirable pixels of a photo to be noise.

Here is the data spitted out by dcraw commandline utility.

Filename: Pictures/2008-01-16–06.53.37/dsc_2397.nef
Timestamp: Tue Jan 15 19:31:44 2008
Camera: NIKON D100
ISO speed: 320
Shutter: 10.0 sec
Aperture: f/29.0
Focal length: 70.0 mm
Embedded ICC profile: no
Number of raw images: 1
Thumb size: 570 x 375
Full size: 3040 x 2024
Image size: 3037 x 2024
Output size: 3037 x 2024
Raw colors: 3
Filter pattern: GRBGGRBGGRBGGRBG
Daylight multipliers: 2.614252 0.930754 1.396616
Camera multipliers: 360.000000 256.000000 724.000000 256.000000

Now, I don’t claim to know what every piece of information printed above means. But the ISO setting tells me that 320 is not a very high light sensitive setting.

But here is the detail:

That photo was at 25% magnification of the original. The 100% cropped picture is below:

And this is just at 100%. I wonder what happens at higher magnification or at higher ISO. Would be a good thing for study, wouldn’t it. There is of course one piece of detail that may be relevant. The white balance I used is of filament bulb. But the lamps are of “warm white” compact fluorescent! Are they somewhat the same? Hmmm….

Flowers and plants

FourEyes — Tue, 27 Nov 2007 04:40:30 +0000

In some ways, I am quite lucky. Both sets of parents (mine and my wife’s) are keen to have some plants around the house. On a recent trip to my in-laws place, I was indeed armed with my camera and more than enough time to explore the entire place for treasures. And the loot was quite spectacular. The highlight of this treasure hunt was that my father-in-law exclaimed that the pictures of the plants/flowers looked better than the real things themselves!

Here are some examples

Normally, I rely on the judgement of the camera to take a good photo, but often get a bad one due to goof-up on focusing. This time, I tried aperture and shutter priority to play with focusing. The results were very good and I felt as if the practicals of a theory session were coming true to my eyes.

I think I may still be a slave to technology and paying less attention to technique. But the journey of learning will be very enjoyable if these photos are any indication.

Happy Diwali Indeed!

FourEyes — Mon, 12 Nov 2007 15:09:02 +0000

Now that one of my Nikon lens (AF-S DX Zoom-Nikkor 18-70mm f/3.5-4.5G IF-ED (3.8x)) has got some moisture-fungus, I have been picking up my camera more often. I have been a bit sluggish with the part where I take it to the Service Centre.

Nevertheless, the camera did see the light of day (pun unintended), this Diwali (the festival of … what else… lights!). I don’t claim to have much expertise. But just the fascination with some techniques and subjects. I have just posted the relevant data alongside the photo, to see how things change with the settings.

Photo	Data
Common data Camera: Nikon D100 Lens: Nikkor 50 mm f/1.8 D Flash: Nikon SB-50DX SpeedLight Filter: Tiffen Haze-1 (UV)
	Programmed AutoMulti-Pattern Metering 1/8 s at f/1.8 ISO 200 Flash: Not used
	Aperture PriorityMulti-Pattern Metering 20 s at f/22 ISO 200 Flash: Not used
	Aperture PriorityMulti-Pattern Metering 20 s at f/22 ISO 200 Flash: Not used
	Aperture PriorityMulti-Pattern Metering 25 s at f/22 ISO 200 Flash: Not used
	Aperture PriorityMulti-Pattern Metering 9 s at f/22 ISO 200 Flash: Not used
	Aperture PriorityMulti-Pattern Metering 1/10 s at f/1.8 ISO 200 Flash: Not used
	Programmed AutoMulti-Pattern Metering 1/3 s at f/22 2 Steps over ISO 1600 Flash: Not used
	Aperture PriorityMulti-Pattern Metering 9 s at f/22 2 Steps over ISO 1600 Flash: Not used
	Shutter PriorityMulti-Pattern Metering 1/60 s at f/22 2 Steps over ISO 1600 Flash: Not used
	Aperture PriorityMulti-Pattern Metering 1/15 s at f/1.8 ISO 200 Flash: AF-S, Rear Curtain Slow, D-TTL
	Aperture PriorityMulti-Pattern Metering 10 s at f/22 ISO 200 Flash: AF-S, Rear Curtain Slow, D-TTL
	Aperture PriorityMulti-Pattern Metering 10 s at f/22 ISO 200 Flash: AF-S, Slow Sync, D-TTL

I am quite impressed at the extent of focusing brought about by the f/22 setting. Also, 2 Steps above ISO 1600 causes some sort of noise in the image.

Naturally, more experiments are to follow!

A new mobile phone and a humbling experience

FourEyes — Fri, 02 Nov 2007 06:31:16 +0000

This incident happened a couple of months back, but still manages to scare the life out of me.

I got myself a slick Sony Ericsson Phone – M600i. I got protective and got a cover as well. This cover happened to have a belt clip. Only, with the cover it was very bulky to fit into my jeans pocket. I decided to try the belt clip, only to be cautioned by my wife that her brother managed to lose his phone when it was on the belt clip. Choosing to disregard this advice, I still put it on and went with her to the movies.

It was only when I came back home that I realized that the phone was no longer on the belt. I managed to run quite amazingly well, considering I generally don’t and everyone around me safely puts me down as lazy. A movie was in progress and the security crew informed me that the cleaning crew had not found anything.

Still wanting to see things with my own eyes, I insisted to be taken to the seat I had occupied. We managed to get some people inconvenienced, but I started breathing normally after I found my phone on the floor beneath the seat! The cover is black in colour and was not seen in the low visibility in the hall by anyone else.

It was quite a humbling experience for me. I had placed more trust in a device than my wife’s advice based on an earlier event. Quite silly, now that I look back at it.

my introduction to Calvin and Hobbes

FourEyes — Tue, 30 Oct 2007 05:43:45 +0000

I remember going on a trip to New Delhi and Agra with my parents. My mom wasn’t keeping that well. Her legs gave her an unfair amount of grief. Yet, she was very enthusiastic about visiting the places. Somewhere along the way, my dad got me a Calvin and Hobbes book. My guess is before boarding the flight to New Delhi.

I vaguely remember not being able to make any sense of the twisted logic ingrained in the strips. I still persisted. Maybe because my brother and I are suckers for that kind of humour. The creator obviously saw more through the eyes of Calvin than anyone else. I think a lot of people looking back at their own tryst with the education system, empathise with Calvin. Surely, his learning ability at school (or lack of it) is largely exaggerated.

My favourite, though, is Hobbes. There is the right amount of sarcasm, mischief and fuzziness to have him as the best friend. Though only imaginary, he seems more real to me than a few of the characters that come and go in the strips. There is some amount of innocence in there as well. Unlike Tom and Jerry, where one character gets an upper hand most of the time, I think the pranks are well split up.

There is another habit I have developed. Whenever Calvin is another being (mainly Spaceman Spiff), I have a tendency to look toward the end of the strip to see how it ends! More on Calvin and Hobbes will definitely follow. But for now, I am content uploading Hobbes as my avatar.

strange thing – colour…

FourEyes — Mon, 22 Oct 2007 05:43:52 +0000

Recent developments in computing means automatic functioning of computers and devices, right?

I couldn’t believe my eyes when the Nikon Editor (part of Nikon View software bundled with Nikon digital cameras) showed my captured images in a strange hue of green. On conversion to TIFF though, the colours looked just fine. It seemed to affect only NEF files (RAW image format).

My pc is a Dell Optiplex 740 and is fairly recent. As part of the monitor installation, the correct ICC profile got installed. Yet, not all colours got displayed accurately.

As part of my poking around, I have found that associating the monitor with the colour profile of sRGB (available in windows folder under system32/spool/drivers/color) resolves the matter. I know that my camera captures in sRGB, but not much way to find out what colour profile is associated with the monitor’s driver.

My search is now toward monitor colour calibration and with cameras and printers.

My laptop is out to embarrass me!

FourEyes — Sat, 20 Oct 2007 04:23:30 +0000

I spent almost all of two to three days trying to get the Sun Java plugin wo work in firefox (2.0.0.5 on Fedora 7). It (my laptop) was quite adamantly determined to make me look stupid. I say that because the first draft of the blog post was about how I couldn’t get it to work!

Anyway, I ended up getting distracted by trying to get my PCMCIA wireless LAN card to work (a LinkSys WPC54G). For this I needed to have ndiswrapper. For that I needed to custom compile my kernel. Some would say that is a big distraction!

After coming back to my original Java problem, I thought of generating the rpms myself (Howto: Sun Java on Fedora 7 [Update]). That gave another problem with odbcinst, as discussed on the page.

As a last attempt, I decided to try installing the JDK directly.

Created java folder in /usr.
Ran jdk-6u3-linux-i586.bin.
Created symbolic link for libjavaplugin_oji.so in /usr/lib/firefox-2.0.0.5/plugins/.

And pages with java applets are working!

All I have to say is Bhooppppp! (Read Tintin – title’s name is Land of Black Gold)

swift kick in the …

FourEyes — Fri, 19 Oct 2007 07:20:00 +0000

Here’s one thing I won’t do in a hurry… kill the X-Windows system on my linux box.

I was messing around with Garnome 2.20.0 and thought (uh-oh) what would happen if I just ask Add/Remove Software to remove Gnome. Then I will be able to get the new version to Gnome to work fine.

It removed X as well! (The kick is welcome anytime now!)

My lamp just blew up!

FourEyes — Fri, 19 Oct 2007 01:33:00 +0000

Just kidding!

I got interested in doing some work with exposure compensation on the SLR camera.

I do realize now that I took some time to do all this – I could have played with one image on the pc to create the rest. Hmmm… I wonder how that would turn out…

my favourite rant – traffic

FourEyes — Wed, 17 Oct 2007 06:48:00 +0000

I get the feeling that even my wife is completely disinterested in my rants about the traffic. The place in question is Thane, Maharashtra, India. The people – almost all kinds, having a common factor – breaking traffic rules with some kind of arrogance.

What traffic rules?

I guess this question may be addressed in two ways – one asking about the types of traffic rules being violated, and the other being the outlook of the people violating the traffic rules. Most commonly encountered violation (my observation, may not be the official statistic), is jumping the signal. The other is moving in the opposite direction for the lane.

The latter is best explained by means of an example. One guy managed to travel in the opposite side for the lane and ended up standing bang opposite to me after slamming the brakes hard. Next, he was fairly articulate in expressing that I better move to the side or there would be trouble!

I am increasingly firming up on my opinion that Indians, in general, do not value traffic rules. I may as well be guilty of this trait, but keep it to a minimum by trying consciously. But those who do not, just seem to look around for a traffic policeman. If there isn’t one, then all the mice come out to play.

And all this only seems to get worse with time.