Wednesday, February 11, 2009

CDIA BU Part Time Photography program

Ok. So I'm sitting in class, about a month into the photography program at CDIA and the instructor just mentioned that as a future professional photography it might be a good idea to start blogging about...basically anything. so here I am. Lara is standing and talking about some stuff and I just started my first blog. YIPI.

So today... we're talking about how to clean up the camera sensor. This is the sensor that capture the image and turns it into a digital image file. Any digital camera has one and problem with all SLR cameras (those big ones that have replaceable lenses) is that every time the lens is replaced with another some dust goes into the body of the camera and sits on the sensor. Obviously that's not a good thing since it causes black dots in the captured image. To test whether your sensor is dusty simple shoot couple of photos of a white wall in the highest f stop your lens lets you (lowest aperture) landscape and portrait, different zoom and then compare the images on your computer. try to see if you find black dots in the same location on each of those images, and make sure those are not black dots that happened to be in that white wall you just shot. If you see a dot or two (ooooohhhh) you probably want to verify that those are real dust spots and not something else like sensor issue or dots on the wall. To do that, shoot couple of more photos, this time with the lowest f stop your lens lets you (highest aperture). what you should see now is the same black dots on the same location, just this time they will all be blurry in the same fashion in all the images you take on the second round.

Once verified now comes the scary part. CLEANING YOUR SENSOR... the reason it's scary is because you actually have to take out your lens and start messing around with the internals of your camera, which in a lot of cases and without knowing what you're doing, you'll make more mess than cleaning. The other thing is that the sensor is located in the back of the camera body, behind couple of mirrors that during the photo shoot those are flipped in order for the sensor to capture whenever comes through the lens. The camera should have a sensor cleaning function that will flip those mirrors temporary so you can access the sensor for cleaning. One more concern is static charge, which can happen if you're not following the camera instructions for sensor cleaning and basically can attract more dust to the internals of the camera, including the sensor surface. In most cameras you have to do this while the camera is off and the battery is fully charges (so the camera know to keep off static charges, or something like that).

Ok, you flipped the mirrors and now have access to the sensor surface and no static charges is in a one mile radius (hopefully). Now you actually have to clean the sensor without causing any damage to anything else. At this point I told Lara 'Stop. I'm not doing this. my camera is clean enough. Too scary. I just bought it 3 weeks ago'. In fact, I do have a tiny dust spot in the corner of my frame which does not bother me enough to start an open heart surgery on my precious. So I'm looking at Lara pushing this small air blower inside her camera and I'm like 'ARE YOU INSANE?' apparently she has to do that quite often since the frequent lens changes during her shootings, but me... not yet. I'll wait a little longer until my baby breaks the 5000 photos mark. Besides, removing that small dust dot from the image file while working in Adobe Lightroom takes about 2.8 seconds.

Anyway, for the courageous ones, there are couple of more techniques for cleaning the sensor like using these all kind of solutions you can by and then cleaning the sensor surface with 'Q-tips' kind of brushes. Forgedaboudit ! not for me.

Well... about an hour pasted and Lara is now showing everyone how to create virtual copies and I'm way behind the rest of the class. So, that's it for now. I'll be back sometimes soon. Hopefully.

Ciao