26 February 2012

baSIX of Photography

Given a task to photograph a subject in a particular location, different photographers can come up with different results. Different results can be obtained by varying 6 key parameters.

  1. Shooting the same subject from a different angle.
  2. Keeping the subject in different size and different part of the image.
  3. Shooting from different distance from the subject.
  4. Choosing how bright or dark the image should be.
  5. Shooting with different intentional out of focus of background or foreground in the frame.
  6. Shooting with different motion blur, when there are moving objects in the scene.

not 7. Changing the lighting that illuminates the scene. But it changes the scene/subject. And a photographer may not always have liberty to do it.


A photograph can look great or so so, by varying the above 6 parameters. But what looks good or bad is a matter of taste.

  • But looks like most great award winning or liked, shared, +1ed photographs, won the audience for what was photographed, more than how it was photographed. It is the subject not the photograph itself. Just like it is the story not the writing that matters most.
  • And the professionals seem to use auto-focus a lot. The costlier cameras are made costlier by having more auto-focus points etc... They fall back to manual focus only when AF fails. IOW actually professional camera's are easier to use than a consumer/prosumer cameras with lots of limitations.

Might be continued... this is an excerpt from my very long notes. It continues on to explain how to vary the above 6+ parameters, and which kind of equipment would help achieve them.

13 February 2012

பிரம்மாண்டர் ஷங்கர்

டைரக்டர் ஷங்கரின் பிரமாண்டத்திற்கு அளவே இல்லை. ரெண்டு சீன்ல வரும் எஸ்.ஜே. சூர்யாவுக்கு இளைய தளபதி விஜய டூப்பா போட்டிருக்கார்.

29 December 2011

Casual Consumer Photography Musings

I am neither a professional nor an amateur photographer, but a common man who uses his phone cameras and point-and-shoots. Here are some of my musings related to photography, which are possibly meaningless or wrong.


Digital Zoom

Many point-and-shoot and phone cameras discourage digital zoom. For example, Android cameras set at max resolution don't allow digital zoom beyond that. The reason is that, the image can be cropped any time later during post-processing.
This is true for camera's that store images in lossless/RAW formats. Otherwise quite some detail is lost, when the image is compressed in camera, and then later when cropped and blown-up("digital zoomed") in a PC. If we digital zoom on the camera itself, before compressing the image, more details could be retained! I could see that digitally zoomed image on my point-and-shoot is better than zooming in later during post-processing.


Panorama

Creating panoramic images was too hard long back, but not any more. My phone camera which has an accelerometer, but doesn't have a gyroscope is able to stitch and generate low-res panoramas in no time. Latest phones and cameras all have gyroscopes and do a better job with this.

I tried clicking panning few panoramas in my friends marriage hall with my phone.

And I feel that this format of very ultra-wide-angle is the best/must format for covering marriages! Hope wedding photographers/videographers would start adding panoramas to the mix. If you are planning to spend a lot on wedding photography, ask for panoramas/super-duper-ultra-wide-angle high-resolution shots.


180°/360° Panorama Videos

Awed by the panoramas from my phone. I wanted to shoot panorama videos i.e., videos with 180° or more FOV. Imagine placing/hanging a 360° Video camera in the center of the wedding hall.
One way to do it would be to create an circular array of cameras and stitch the videos together later. Another way could be to have a shining Christmas tree ball/convex hemispherical mirror and shoot a video of the image on it with a camera, and later post process it to do distortion correction. The same could be achieved by shooting on a camera with a fish-eye lens. Even better would be to use a circular fisheye lens and get a 360
° (on one axis) video. Or 2 or more such cameras to create the complete 360x360 video. I found few 360x360 stills, but no videos. Also found few uncorrected 360°(single axis) videos.

I am trying to shoot pics/video using all shiny balls, door handles now :) I also tried to shoot videos simultaneously with 3 cameras phones with limited FOV, and tried stitching them together. Even when they are stitched badly, it has a good effect.


Lens and focal length

All the photographic equipment manufacturers use focal length for lenses, even on those that are targeted at consumers. With variety of sensor sizes, it doesn't seem to make sense at all. How does it matter to me, what is the focal length? Why cant they just mention the FOV instead? Focal length is an implementation detail, I am not interested in.


Might be continued

Will be continued, if more thoughts on fast-frame rate cameras that help creating super slow motion videos(which can be another nicety in marriage coverage), Light field cameras, 3D cameras and dreams of combining these together like 360
°x360° Super slow motion 3D light field video will continue to occupy my mind...

30 January 2011

Real hackweek, protected hackweek and long hackweek

I have been using KVM a lot, but never took time to understand how kvm works. I used some time from this hackweek to get rid of that regret.

Virtual Machine eXtensions instructions allow trap-and-emulate virtualization. And KVM exposes VMX in a convenient way to userspace in Linux. Virtual Machine Monitors(VMM) like qemu-kvm use the KVM API exposed by linux to emulate virtualize software.

x86_64 processors boot in real-mode. In this mode it can use only 16-bit addresses, ie., upto 1MByte RAM. The execution would begin at physical address 0xFFFFFFF0. Then the software has to switch to protected mode where protection and paging is possible. Paging is optional, but almost all OSes use demand paging extensively. Now 4 GBytes of linear address space is used. And then CPU can be switched to long mode i.e., 64-bit mode. Paging should be disabled in 32-bit mode, before switching to long mode. There are also other modes of operation like virtual-8086 mode to allow executing legacy real-mode software from protected mode, SMM for OS transparent execution of OEM specific code.

I had limited time and very very limited skill at hand. So aiming for the sky was not an option. Hence wrote a very simple VMM that directly starts the guest at address 0H, in 32-bit protected mode with paging disabled. And supports only insb and outsb as the only form of interaction possible for the guest. The guest is a simple static linked 32-bit program that doesn't use any library, and linked to start from 0x0. The guest simply reads a byte using insb and sends byte+1 back via outsb. The guest would halt, when it gets the, "Answer to the Ultimate Question of Life, the Universe, and Everything". The VMM reads the byte value to pass to the guest from stdin and prints its response in stdout.

The KVM API is really very easy to understand and use. But some knowledge of the processor was required to make use of it. Intel manuals helped there. I don't have good understanding of things yet, but something is better than nothing.

I was occupied by quite a lot of things in life and work in the recent past. So I wasn't really planning to participate and make this a real hackweek. Also a National holiday for Republic day of India, bang in the middle of the week prevents this hackweek from being a long hackweek! But seeing videos of my colleagues from various parts of world having fun, I couldn't resist and decided to go for the virtual hackweek. I thank my employer for giving me this protected hackweek, and let me learn/do things protected from everyday work.

29 November 2010

Panorama

Played with Hugin. It was fun.




Made using Canon A570 IS + Hugin on openSUSE.

Should try on some great places and outdoors.

I have a scrolling animation of the above image as a Google Gadget in my blog now.

20 October 2010

தமிழில் க(ka/ga), ப(pa/ba), ட(ta/da), த(tha/dha) -Tamil contextual pronunciation?

தமிழில் க(ka/ga/ha), ப(pa/ba), (ta/da), த(tha/dha)

Some of my friends believe that there is no "gha" in tamil and there is only "kha", only "pa" and no "bha", only "ta" and no "da", only "tha" and no "dha"

But I pronounce differently depending on the word/context

அகற முதல எழுத்தெல்லாம் ஆதி
பகவன் முதற்றே உலகு

aghara muthala yeluthellaam aadhi
bhaghavan muthatrey ulaghu


ஆம்பல் - aambhaல்
விருந்தோம்பல் - virunthombal
பலா - palaa
நிபுணர் - Nibhunar
கடலூர் - cuddalore
கட்டுமரம் - kattumaram

எது சரி ?

04 August 2010

Wrong from illite"race"y

"Right to education" act mandates all schools, including those elite ones, should admit 25% of students from its locality without any test or filtering. I think this is a very good move by Government of India.

But the schools and highly literate rich parents are not welcoming this. No one is denying them the rich the right to education. But they want to remain elite and are afraid of the poor.

http://expressbuzz.com/cities/bangalore/controversial-circular-decried/195084.html
http://www.mybangalore.com/article/0810/parents-in-bangalore-not-okay-with-rte-act.html

http://expressbuzz.com/cities/bangalore/parents-say-no-to-inclusive-classrooms/195349.html

Their concerns are
1. Quality of education will suffer.
2. Rich students will learn foul language from poor students.

They should think for a moment, how they felt when their kid was denied admission by a school, which is considered to be slightly better than the one, where their child is currently studying! Not getting admission there will not affect their kid by much. But imagine the difference, it could mean to the poor kid.

Class system by birth still remains. Just that it has become modernized. The rich wants to makes sure that the poor cannot get quality education or get richer. The ancient class system was not as bad as, this mindset of these literates! Gandhiji would be proud of you, intelligent Indians. Untouchability is a sin.

All poor and illiterates are not bad in character or lack mental ability. Not all rich and educated have the best of character with highest mental ability. One's character or intelligence has nothing to do with his economical status.

I firmly believe that if this gets implemented correctly, many of the toppers will be from the 25%. I wonder what is the opinion of "Youth for equality" on this issue. IMO this 25% reservation is not a reservation. But the 100% only rich and educated is the 100% reservation. I love RTE.

28 July 2010

Hey Buddy

Another draft from 3/1/08

In a chat room
x: Hey buddy
y: Dei, Now I have done laser da

x & y are Tamil people

buddy != புட்டி