This morning I was playing with the Linux OBI (which is a desktop Linux distribution, based on Oracle Enterprise Linux 5.0, with all the drivers and everything for everyone's stock notebook). My employer actively encourages its minions to use the Linux OBI so that hopefully the tax we pay to malaria donors will go down.
The Windows installation on my 18 month-old notebook has been inexplicably slowing down in the past months anyway, and I already had a dual-boot Linux setup (albeit not the OBI, so the Intel wireless didn't work) so I thought I could "try out" the OBI on the existing Linux partition.
The OBI install is a stock Oracle Enterprise Linux 5.0 (based on CentOS 5.0 installer)... or so I thought.
In a clear and egregious violation of the Principle of Least Astonishment, the OBI installer downloads a kickstart file from somewhere in Global IT's guts and... partitions and formats your hard drive without asking any questions. No "will I use this existing Linux partition?" or anything like that...
It so happens I have almost two years worth of data on that 100GB notebook drive. Most of which I neglected to back up. Oops.
So I had to go running off to the mall to buy a 2.5-inch SATA drive case. And now I'm using some downloaded software off the net to image the notebook hard disk (on my desktop -- good thing I have a 500GB drive in this thing) so that afterwards I can try recovering the partitions and my precious files: off the image, to be safe.
Thursday, July 31, 2008
Sunday, July 27, 2008
How Bad Is The Hanimex?
Compared my (badly) repaired Hong Kong Hanimex 135mm f/2.8 with the famous Pentax SMC-M 135mm f/3.5 at comparable apertures.
The original photo:
As expected, at f/2.8 it's pretty bad, getting better as I stop down. Of course the Pentax shows no image at f/2.8 so even a bad image is better than nothing. Peak performance is obtained at f/8, degrading due to diffraction at f/11.
The Pentax is better at all apertures except f/2.8 (obviously). It also exhibits higher contrast, almost certainly due to the better coatings. It did cost me $40 on ebay (as opposed to $1.00). However when factoring in the cost of shipping, the Pentax is "only" four times more expensive (about $60 versus $15). Is it worth it? of course. But sometimes you need the faster aperture.
| f/2.8 | f/4 | f/5.6 | |
| Hanimex |  |  |  |
| Pentax |  |  |
The original photo:
As expected, at f/2.8 it's pretty bad, getting better as I stop down. Of course the Pentax shows no image at f/2.8 so even a bad image is better than nothing. Peak performance is obtained at f/8, degrading due to diffraction at f/11.
The Pentax is better at all apertures except f/2.8 (obviously). It also exhibits higher contrast, almost certainly due to the better coatings. It did cost me $40 on ebay (as opposed to $1.00). However when factoring in the cost of shipping, the Pentax is "only" four times more expensive (about $60 versus $15). Is it worth it? of course. But sometimes you need the faster aperture.
$1.00 Lenses
Sometimes my ebay adventures take a turn for the unexpected. A couple weeks ago I bid on an item with the following description:
Got the lenses a couple days ago. Did I mention that I won the auction with a $2.00 bid? of course what with US shipping and forwarding to the Philippines, it ended up a bit more expensive than $2.00. Here's what I got:
The "Image" brand f/3.5 200mm lens is identical to my Hanimex which I got from Adorama for $20 or so, about four years ago. It's not a Komine lens because it only has six blades in the diaphragm. It has lots of fine scratches on what looks like the second element. They look like breakage, maybe in a cemented element. Not worth fixing, since the scratches are far from the nodal point, they won't affect image quality. Not that these dubious 3rd-party 1970's Japanese lenses were particularly great..
The diaphragm wasn't stopping down properly either, and the distance scale was off. A little disassembly and poking around fixed all of these issues and restored 100% functionality (except for the scratches on the glass, of course).
As for the 135mm.. it's a horrific piece of plastic work, made in Hong Kong. Hanimex really scraped the bottom of the barrel with this one. Green coating. Single-coated?
Almost everything about it is plastic. The reason the stop-down pin disappeared is that the shaft of the stop-down lever (inside the lens) was made of plastic and broke off. So the lever and pin fell into the guts of the lens.
What I did was to make a hole in the (plastic) inner barrel with a soldering iron. I then sacrificed one of the screws that held the M42 mount (mercifully, the mount is aluminum) to use as a shaft, as none of my screws were thin enough.
Dodgy, but it works (after a fashion). The screw was too long and the stop-down lever was wiggling, so I bent a bit of paper clip around the screw end to serve as a washer. Talk about a McGyver moment..
There even are instructions on how to disassemble and reassemble it!
Notice the mismatched screw. Had to use one I had lying around because I'd sacrificed the "real" screw to use as a shaft.
In total, after a couple hours' amusement, I got both my $1.00 lenses back to normal functionality. You may ask, why even bother, when the K10D can't stop them down anyway so it's useless functionality. Fixing these lenses is like climbing Mount Everest.. because they were damaged. And I could.
Wasn't dirt-cheap in the end because I paid some amount for the US-Philippines shipping. So not exactly $1.00 lenses after all is said and done. I got a redundant 200mm lens, and a 135mm f/2.8 (the extra stop over my existing f/3.5's may prove useful).
The 135mm is soft at f/2.8 (hardly unexpected!) but I have yet to compare it to the famous SMC Pentax-M 135mm f/3.5, because I couldn't stop it down before I finished repairing it. If it can match the Pentax at f/4, I will be (1) extremely amazed; (2) quite gratified. If not.. well it's a plastic Hong Kong Hanimex.
Two Pentax screw mount M42 lens for repair, or parts.I thought, "I don't have any f/2.8 135mm lenses, so might as well." I do have three f/3.5 135mm lenses though. I thought, the missing M42 stop-down pin was not a huge problem, since no modern DSLR can stop down an M42 lens anyway.
Image 1:3.5 f=200mm Camera Lens. Has some scratches inside of glass.
Hanimex Automatic 135mm 1:2.8 Lens. Bottom pin is missing. It sounds like it is inside of lens, when you shake it.
Got the lenses a couple days ago. Did I mention that I won the auction with a $2.00 bid? of course what with US shipping and forwarding to the Philippines, it ended up a bit more expensive than $2.00. Here's what I got:
The "Image" brand f/3.5 200mm lens is identical to my Hanimex which I got from Adorama for $20 or so, about four years ago. It's not a Komine lens because it only has six blades in the diaphragm. It has lots of fine scratches on what looks like the second element. They look like breakage, maybe in a cemented element. Not worth fixing, since the scratches are far from the nodal point, they won't affect image quality. Not that these dubious 3rd-party 1970's Japanese lenses were particularly great..
The diaphragm wasn't stopping down properly either, and the distance scale was off. A little disassembly and poking around fixed all of these issues and restored 100% functionality (except for the scratches on the glass, of course).
As for the 135mm.. it's a horrific piece of plastic work, made in Hong Kong. Hanimex really scraped the bottom of the barrel with this one. Green coating. Single-coated?
Almost everything about it is plastic. The reason the stop-down pin disappeared is that the shaft of the stop-down lever (inside the lens) was made of plastic and broke off. So the lever and pin fell into the guts of the lens.
What I did was to make a hole in the (plastic) inner barrel with a soldering iron. I then sacrificed one of the screws that held the M42 mount (mercifully, the mount is aluminum) to use as a shaft, as none of my screws were thin enough.
Dodgy, but it works (after a fashion). The screw was too long and the stop-down lever was wiggling, so I bent a bit of paper clip around the screw end to serve as a washer. Talk about a McGyver moment..
There even are instructions on how to disassemble and reassemble it!
Notice the mismatched screw. Had to use one I had lying around because I'd sacrificed the "real" screw to use as a shaft.
In total, after a couple hours' amusement, I got both my $1.00 lenses back to normal functionality. You may ask, why even bother, when the K10D can't stop them down anyway so it's useless functionality. Fixing these lenses is like climbing Mount Everest.. because they were damaged. And I could.
Wasn't dirt-cheap in the end because I paid some amount for the US-Philippines shipping. So not exactly $1.00 lenses after all is said and done. I got a redundant 200mm lens, and a 135mm f/2.8 (the extra stop over my existing f/3.5's may prove useful).
The 135mm is soft at f/2.8 (hardly unexpected!) but I have yet to compare it to the famous SMC Pentax-M 135mm f/3.5, because I couldn't stop it down before I finished repairing it. If it can match the Pentax at f/4, I will be (1) extremely amazed; (2) quite gratified. If not.. well it's a plastic Hong Kong Hanimex.
Sunday, July 20, 2008
ALP Get-Together at PAGASA
Lalai and I went to the Astronomical League of the Philippines get-together and photo opportunity today, Sunday afternoon, at the PAGASA observatory in UP Diliman.
It's been a while since we were back there, several years at least. The first time Lalai and I went there in 2003, we carried our ETX-60AT telescope in a backpack and took the bus. Something I wouldn't care to try these days..
Several of the members brought their telescopes to use as props for the photo opportunity.
One of the members brought his rebuilt 8" Discovery dobsonian telescope. He built the tube out of plywood and it has a very fine finish. Very much like the telescopes built by Normand Fullum (except without the fauns and fantastic carvings).
I'm very inspired to rebuild my 10" dobsonian (yet again) in this type of format. True, it doesn't break down well anymore, but at least it's solid and holds collimation well. It would take up the entire back seat of our car though, which is quite a negative.
PAGASA has been very much in the news recently because of the sinking of the Princess of the Stars ferry a month ago. The reprobate shipping company has been blaming PAGASA for not forecasting the weather correctly.
The PAGASA observatory seems to have a leaky roof, which explains the plastic water containers distributed over the floor of their building lobby. It's no surprise that PAGASA has shortcomings in the weather department, if they can't fix a leaky roof!
It's been a while since we were back there, several years at least. The first time Lalai and I went there in 2003, we carried our ETX-60AT telescope in a backpack and took the bus. Something I wouldn't care to try these days..
Several of the members brought their telescopes to use as props for the photo opportunity.
One of the members brought his rebuilt 8" Discovery dobsonian telescope. He built the tube out of plywood and it has a very fine finish. Very much like the telescopes built by Normand Fullum (except without the fauns and fantastic carvings).
I'm very inspired to rebuild my 10" dobsonian (yet again) in this type of format. True, it doesn't break down well anymore, but at least it's solid and holds collimation well. It would take up the entire back seat of our car though, which is quite a negative.
PAGASA has been very much in the news recently because of the sinking of the Princess of the Stars ferry a month ago. The reprobate shipping company has been blaming PAGASA for not forecasting the weather correctly.
The PAGASA observatory seems to have a leaky roof, which explains the plastic water containers distributed over the floor of their building lobby. It's no surprise that PAGASA has shortcomings in the weather department, if they can't fix a leaky roof!
Thursday, July 17, 2008
Heading Home
Heading home after three days' worth of presentations at my employer's FY 09 ASEAN kickoff. Our fiscal year is around a month and a half old, so far.
It's been very busy, and the entire third day has been devoted to the vast new product offerings from the BEA acquisition (including some truly jaw-dropping list prices, at least for me).
In any case, I haven't had any time to go around (despite the Singapore Sale still being on, more or less: 32" Sony Bravia for the equivalent of 24,000 pesos) and my lugging my DSLR and three lenses has been pretty pointless. Still, some photos in the most pedestrian of places:
Self-portrait, elevator, Fairmont Hotel (we'd been barred from the usual Conrad or Ritz-Carlton for cost efficiency; also, our entire event was held at the adjoining Raffles City Convention Center).
Esplanade "Durian" and the Maybank building overlooking the Merlion by night. Well, the Durian and Maybank building are very small... I took this photo while walking along the street from Marina Square back to the hotel.
A different perspective on the Merlion, from my hotel room's balcony. Taken with a 200mm lens:
It's been very busy, and the entire third day has been devoted to the vast new product offerings from the BEA acquisition (including some truly jaw-dropping list prices, at least for me).
In any case, I haven't had any time to go around (despite the Singapore Sale still being on, more or less: 32" Sony Bravia for the equivalent of 24,000 pesos) and my lugging my DSLR and three lenses has been pretty pointless. Still, some photos in the most pedestrian of places:
Self-portrait, elevator, Fairmont Hotel (we'd been barred from the usual Conrad or Ritz-Carlton for cost efficiency; also, our entire event was held at the adjoining Raffles City Convention Center).
Esplanade "Durian" and the Maybank building overlooking the Merlion by night. Well, the Durian and Maybank building are very small... I took this photo while walking along the street from Marina Square back to the hotel.
A different perspective on the Merlion, from my hotel room's balcony. Taken with a 200mm lens:
Saturday, July 05, 2008
More Lens Testing
I got another chance to test the accuracy of focus of the Chinese split-image focusing screen on my Pentax K10D. I had actually done a bit more correction and added an additional layer of sticky tape to the screen.
Original image:
The cropped portion is boxed in the center.
With Candidate #1:
and with Candidate #2:
Both images taken wide open (f/4), 1/1000 second, ISO 100, 200mm focal length.
Original image:
The cropped portion is boxed in the center.
With Candidate #1:
and with Candidate #2:
Both images taken wide open (f/4), 1/1000 second, ISO 100, 200mm focal length.
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