Sunday, March 11, 2007


Forensic Science is now becoming one of my most fun module for the semester even though I'm struggling to cope with the continual assessments. Other than the written work part, the class is fun and interesting, the group of people I'm doing the module with is also funny and cute, a far cry from other modules which I do alone, and most importantly, all the optional stuff organised by the lecturers and tutors make this module so fun to learn. Indeed, rather than a studying module, this has been a learning experience for me.

Until now, I've been to both the field trips organised by the class, and yesterday morning, I went for this lab session to do a hands on experience with fingerprinting. I'm quite lucky to be able to be slotted into this lab session because I didn't sign up for the class through conventional means. I missed the deadline for the IVLE groups signing up, also because there was a screw up with the IVLE groups. I wasn't that all enthusiastic then so I didn't bother to address the problem. However, later I realised that Shuyi was going for the lab session alone, so I thought maybe I could join her, and also because A/P Stella Tan said that the session would be very useful so I emailed the TA and got myself a place covering some other person who backed out at the last minute.

To cut the long story short, this session was a blast. I learnt so much that can't be taught by books. And through the speaking with the tutors there, I learnt more about the topic on hand and the rationale behind fingerprinting. I think not just the students got to learn a lot more about the methods of the collection of fingerprints but the tutors learnt a lot too. The fun part of the photofest started with the lecturers documenting our learning process, but as we went on, my group started taking out our handphone cameras and taking pictures of all our exhibits, then Prof Stella started taking group pictures of us and the exhibits. This is called having fun while learning. Quite a pity the last semester people didn't get to do such interesting stuff. hehehe~

We went through four methods of collection of fingerprints in lab today. The first one is the use of Ninhydrin, some sort of weird chemical. First we sprayed the colourless liquid thingie on a specimen, then we microwaved it. It came out after microwaving with purplish prints on the specimens. This is a very effective method in the collections of prints which have been around for a very long time, it can apparently detect prints from ten, twenty years ago.

This the Ninhydrin thingie. The class was split into groups of 25 then sub divided into groups of 6-7. My group of 25 used up like half the bottle of that thing. It's like finally seeing where my school fees were going to. Previously in Arts the school fees seems to be wasted on paying for lecturers only, but now, in this class, there's at least some use of the school fees, like the gloves we wore, the disposable lab coats, all these materials.

This is magnetic dusting. Inside that can is magnetic powder, the magnetic rod can stick up the powder onto the tip and it looks a bit like a brush. I first thought that it was a brush instead of merely a rod and the magnetic powder were the bristles of the brush. haha... Suaku me... So we use that rod to dust the surface of the specimen to locate the prints.

The print taken from that method is very clear and distinct. But of course, since the magnetic powder is black in colour, it's best used for materials which are light coloured so that we can see the print. Personally, I prefer this metod the most because it's the least troublesome one and can detect the clearest and most distinct prints. Wonder if we can get a can of that magnetic powder and start dusting my stuff on my own anot. hehehe~

This is the dusting of normal fingerprint powder, the one I took a picture on is the white powder which can be used on dark coloured surfaces, but there's also the black fringerprint powder to be used on white surfaces. It's something like the magnetic powder just that it's not that cool. hehe... The brush is like some normal brush to dust lightly over the surface of the specimen. The print would then appear. But these powders can only detect fresh prints. Actually, we can also do this at home with normal powder and dust for prints, just that the prints we get might not be that clear because these fingerprint powders have been optimised to the best effects, whatever that it. I only know that the powder is supposed to detect the oil off from our fingers onto those surfaces, to leave the ridges of our fingerprints.

To document and keep these prints, we use a sticky tape thingie to stick onto the powder of the prints and keep it as shown in the picture there. The prints of this method however is blurry and not that clear, couple with the fact that most criminals when committing the crime don't bother to leave us with nice clear prints in tact, I personally thing that this is quite useless. hehe... But to the police, it can help to narrow down suspects.

The last method we tried out was superglue fuming. The picture shows some weird chemicals that can help induce the fumes of the superglue which can leave marks on specimens that has fingerprints on them. Apparently, it's one of the more common methods used by the police because that can fume the whole room at one go. However, we of course can't fume that much, only on our specific little area of created specimens. It's quite lame since our prints are very nicely marked because we were careful to make sure that we left our prints all over.

This the set up, it's quite blur because we were the last sub group to use that set up and the plastic bag has been fumed by all the other sub groups before and everything's a fog. It's so funny because after all the years of being an arts student in JC and Uni, I forgot what's that stand thingie called. When I asked my group mates, they were like "It's a (edited for spelling mistake)retort stand.", momentarily I really felt very stupid. Oh well... More proof that I'm definitely not made out for Science.

This the specimen. I thought that it's very clear that a print has been detected by the ridges of the print isn't that distinct, so I don't really think that it seems like a very efficient method. But of course, it's probably that my group didn't do it that well, the police might be doing a better job than us. hehe... Some of the prints on other materials also didn't really come out to be that obvious.

It was fun la, the whole session. BUT THEN HOR, what we watch on TV is like so different. There's no such thing as getting clear distinct prints on every possible thing, and also, apparently the matching of fingerprints detected to a person is very labourious and difficult. Because our database only contains thumbprints of every Singaporean, and the ten fingerprints of everyone who has been detained before, so if a clean criminal comes about, it's very difficult to identify him based only on the fingerprints. Also, the software system of matching fingerprints is bullshit. The tutor said that on a normal day, an input of a print can come up with 40-50 matches.

So, really, if we want to commit crimes, there isn't really a need to wear gloves. lol~ Just make sure that our hands are dry and not oily, maybe can put powder or some drying agent. hehehe~ And also, don't be a good citizen and volunteer your prints for database purposes. lol~


Poo said...

Retort stand, not retord stand. :p

Anyway, forensics does seem interesting. I'd like to find out more myself. :)

xxoos said...

haha... more proof that i still do not know what is that stand thingie~ thanks man...

the actual classes is quite interesting, especially when going through case studies. we get quite a lot of interesting cases, especially those chopped up bodies kind... hehe...