The “official” blog of Melinda and Christopher Williams and family
Wednesday, December 21, 2011
Sunday, July 10, 2011
Fungus Among us
Somehow I managed to get fungus inside my day-to-day DSLR lens. This lens (a Sigma 18-50mm f3.5-5.6 DC lens) cost me only $37 with shipping via eBay, and having it cleaned professionally would cost more than the lens itself. I decided to clean it myself!
It took me about an hour to open it up and clean it (I didn't want to have spare screws when I was finished), but I eventually got the fungus off the inside lens element with isopropyl alcohol. There appears to be some small amount of etching left on the element (fungus secretes hydrofluoric acid), but it doesn't seem to be visible in photos taken with the lens.
Unfortunately, after cleaning and reassembling the lens, my camera showed the aperture go up to 5.0 at the 50mm end (it should be 5.6 at 50mm). The lens thought it was only at 37mm, according to the EXIF data in the JPEG files. I probably bent one of the electrical contacts around the inside of the zoom ring which tells the lens and camera what the current focal length is. For those technical geeks (like myself), there are five electrical contact strips running around the lens underneath the zoom ring, and they appear to be encoded using Gray coding; the contacts on the zoom ring make contact with those strips, which in turn tells the lens the position of the ring. Gray coding is pretty neat and useful that way. (Incidentally, five tracks provides up to 32 combinations, and there are 33 different focal lengths (50-18+1=33). I wonder which focal length(s) are not represented by the lens.)
I took the lens apart a second time (though not as far as the first time), and I straightened out the contacts. After reassembling again and testing again, the focal length is being reported correctly! Woot!
I just hope that I don't get fungus in this lens again. :/
It took me about an hour to open it up and clean it (I didn't want to have spare screws when I was finished), but I eventually got the fungus off the inside lens element with isopropyl alcohol. There appears to be some small amount of etching left on the element (fungus secretes hydrofluoric acid), but it doesn't seem to be visible in photos taken with the lens.
Unfortunately, after cleaning and reassembling the lens, my camera showed the aperture go up to 5.0 at the 50mm end (it should be 5.6 at 50mm). The lens thought it was only at 37mm, according to the EXIF data in the JPEG files. I probably bent one of the electrical contacts around the inside of the zoom ring which tells the lens and camera what the current focal length is. For those technical geeks (like myself), there are five electrical contact strips running around the lens underneath the zoom ring, and they appear to be encoded using Gray coding; the contacts on the zoom ring make contact with those strips, which in turn tells the lens the position of the ring. Gray coding is pretty neat and useful that way. (Incidentally, five tracks provides up to 32 combinations, and there are 33 different focal lengths (50-18+1=33). I wonder which focal length(s) are not represented by the lens.)
I took the lens apart a second time (though not as far as the first time), and I straightened out the contacts. After reassembling again and testing again, the focal length is being reported correctly! Woot!
I just hope that I don't get fungus in this lens again. :/
Wednesday, February 16, 2011
Photo dump
I'll let Melinda caption these better. :) Ok I added some stuff to Chris pics but I think the wedding pics speak for themselves.
Pre-Christmas party at the Garbison's
Alex splashing in the tub.
John and Jolene's pre-Christmas party
Alex always has to take a sip of mommy's drink!
Emma and Baby Ben
Pre-Christmas gathering at the LeSueur's. Alex thinks Mommy's legs are a slide!
Benjamin!
Julie's wedding reception
Yummy crepes!
Emma's birthday party
Emma getting smothered by Auntie!
Emma sporting the new play scrubs I made her for her birthday.
Tuesday, November 2, 2010
First Food!
This is baby Ben's first attempt at rice cereal at 4 months of age. Unfortunately he threw up so violently afterward that I decided to wait to try again at 6 months. The doctor told me to start him on solid food and he told me to potty train Alex. I think next time he tells me to do things so early I'll offer to let him come to my house and show me how it's done!
Wednesday, October 13, 2010
Serious Sillyness
Chris bought himself a camera as an early Christmas present and we had fun taking pictures. I think this is how he plans to answer the door on Halloween.
Me sporting my sunglasses.
Alex sporting my sunglasses wearing his BYU T-shirt that I found at a Walmart near Manti.
Another picture of Alex. I think he is asking daddy why so many pictures.
Ben is just serious cuteness! I love my boys and am so happy to be their mom.
Sunday, October 10, 2010
Baby Ben Flipping over at 4 months old
Ben starting flipping over when he was 4 months 2 days old. The other day Chris took pictures while he did it! We adore our new baby boy and can't believe he is growing so fast.
Saturday, October 9, 2010
Samsung HZ30W is a hater
Here are a few image samples that highlight the poor image quality of the Samsung HZ30W (aka WB600) camera. Sure, it has a 12-megapixel sensor, but in this case more pixels only means there are more pixels to look like garbage.
Samsung hates Winston Churchill:
Note the "jittery" noise clearly evident all around his face, hand, and medals. This same noise is also apparent along the capstone above the banner (meaning this noise is not in the banner itself, but rather from the Samsung that took this picture of the banner).
Samsung hates trees:
These trees look plastic. This appears to be the result of selective blur, which tends to make images look like plastic if done without regard to the subject. Also notice the "jittery" noise again in this image along otherwise straight lines.
Both of these images are unscaled crops from this review of the Samsung WB600. These same effects (or rather, defects) occur in nearly all of the images on that page, whether the images have a low or a high ISO rating (which affects sensor graininess), low or high shutter speed (which affects motion blur), and focal length/aperture width (which both affect focus). I was originally thinking that the jittery noise was due to the built-in Image Stabilization (IS), but that shouldn't cause any visible artifact in exposures with high shutter speeds, which would experience little to no motion blur anyway as a result of camera shake. That's not the case as it's present in images with shutter speeds up to 1/500 second.
Samsung also hates children and... water?
My son even looks like plastic. The water behind him has what I call "speckle" noise, where the water is relatively smooth except for a number of significantly brighter or darker small spots (most of them are very short horizontal or vertical lines). This is probably another result of indiscriminate selective blur performed on a fairly noisy (or "grainy") image. This image was taken at ISO 240, so that is likely the case.
This is an unscaled crop from a picture my mother took of my son with her HZ30W.
Can this image processing be disabled on the camera? Even if it can be disabled, a better question is, "Why does it process images this badly by default?" Do people really want jittery, plastic-looking images from their fancy cameras?
Ironically, my wife's 4-year old Nikon Coolpix E4600 produces consistently better images with its 4-megapixel sensor than this Samsung. Of course, you could simply blur or scale the Samsung's images by about 50% to get similar quality, but you would have only 3-megapixel images as a result. So much for technological progress.
I won't even go into a full comparison of this camera with my recently-acquired Canon EOS 10D DSLR camera, but suffice it to say that it blows this camera out of the water in terms of image quality with its 6.3-megapixel sensor. It even cost me almost the same as a new HZ30W—about $150 with shipping and handling. (If I wanted to buy a really high-end lens for the 10D, then yes, it would cost me a pretty penny, but that's not even an option available with the HZ30W. Just sayin'...).
NB: I saved the above crops as PNG images to avoid introducing any further noise. The original pictures were saved as JPEG in "Superfine" or "Fine" quality. The noise in these images are not characteristic of the noise introduced by JPEG compression (such as reduced color resolution and sharp edges along 8x8 pixel boundaries), especially at these high quality levels.
Samsung hates Winston Churchill:
Note the "jittery" noise clearly evident all around his face, hand, and medals. This same noise is also apparent along the capstone above the banner (meaning this noise is not in the banner itself, but rather from the Samsung that took this picture of the banner).
Samsung hates trees:
These trees look plastic. This appears to be the result of selective blur, which tends to make images look like plastic if done without regard to the subject. Also notice the "jittery" noise again in this image along otherwise straight lines.
Both of these images are unscaled crops from this review of the Samsung WB600. These same effects (or rather, defects) occur in nearly all of the images on that page, whether the images have a low or a high ISO rating (which affects sensor graininess), low or high shutter speed (which affects motion blur), and focal length/aperture width (which both affect focus). I was originally thinking that the jittery noise was due to the built-in Image Stabilization (IS), but that shouldn't cause any visible artifact in exposures with high shutter speeds, which would experience little to no motion blur anyway as a result of camera shake. That's not the case as it's present in images with shutter speeds up to 1/500 second.
Samsung also hates children and... water?
My son even looks like plastic. The water behind him has what I call "speckle" noise, where the water is relatively smooth except for a number of significantly brighter or darker small spots (most of them are very short horizontal or vertical lines). This is probably another result of indiscriminate selective blur performed on a fairly noisy (or "grainy") image. This image was taken at ISO 240, so that is likely the case.
This is an unscaled crop from a picture my mother took of my son with her HZ30W.
Can this image processing be disabled on the camera? Even if it can be disabled, a better question is, "Why does it process images this badly by default?" Do people really want jittery, plastic-looking images from their fancy cameras?
Ironically, my wife's 4-year old Nikon Coolpix E4600 produces consistently better images with its 4-megapixel sensor than this Samsung. Of course, you could simply blur or scale the Samsung's images by about 50% to get similar quality, but you would have only 3-megapixel images as a result. So much for technological progress.
I won't even go into a full comparison of this camera with my recently-acquired Canon EOS 10D DSLR camera, but suffice it to say that it blows this camera out of the water in terms of image quality with its 6.3-megapixel sensor. It even cost me almost the same as a new HZ30W—about $150 with shipping and handling. (If I wanted to buy a really high-end lens for the 10D, then yes, it would cost me a pretty penny, but that's not even an option available with the HZ30W. Just sayin'...).
NB: I saved the above crops as PNG images to avoid introducing any further noise. The original pictures were saved as JPEG in "Superfine" or "Fine" quality. The noise in these images are not characteristic of the noise introduced by JPEG compression (such as reduced color resolution and sharp edges along 8x8 pixel boundaries), especially at these high quality levels.
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