Tuesday, December 25, 2007

Spicy Hot Pot

When the weather turns colder nothing warms you from the inside like a big bubbling pot of fiery broth loaded up with meat, veggies, and whatever else you want. This is not a dish for the 100-degree summers of Georgia - it is best enjoyed on a cold winter's evening. The broth is made up of a store-bought hot pot soup base and either water or chicken stock for flavor. In this case we chose a Taiwanese soup base in a jar. Some beef tendon was pre-cooked in the hot pot base using a pressure cooker to soften the tough connective tissue. When cooked for a long time, beef tendon takes on a wonderful gelatinous texture and absorbs the rich flavor of the broth.
The hot pot ingredients can be quite varied and up to your own particular tastes. Usually there's thinly-sliced meat and/or seafood, vegetables, tofu, and tofu skin at a minimum. The great thing about hot pot is you can have whatever you like. On the side there's usually a sauce into which you can dip the cooked bits of stuff. My favorite is sa-cha sauce mixed with a raw egg yolk and a little soy sauce. The other sauce we like is a simple mixture of sliced scallions and vinegar. The vinegar sauce compliments pork very well, but I prefer the sa-cha sauce on everything else. I think I am a sa-cha junkie - I love it with stir-fried beef and I always use it to make a sauce for pan-fried dumplings.
For our hot-pot meats, we took the easy route of buying pre-sliced pork belly and ribeye steak at the local Super H-Mart. The pork takes a little extra attention to make sure it's cooked properly, but the beef only needs 30 seconds or so to preserve it's tender texture. We try to load up heavy on the vegetables and this time we used sliced king oyster mushrooms, enoki mushrooms, brown & white beech mushrooms, and bok choy. We also added tofu that had been previously frozen. The freezing process changes the texture and creates some holes which allow the tofu to soak up the broth. Tofu skin, purchased as dry sheets, is another tasty item which softens up in the broth and soaks up lots of spiciness. Frozen fish cakes and imitation crab meat were added for some seafood flavor, although scallops would have been good too (but so expensive!). At the end of the meal we put in some tang-oh (Garland chrysanthemum - Chrysanthemum coronarium) which soaks up a lot of the spicy oil floating on top of the broth.
This is not a meal for everyone - you have to really love spicy food. This one burns coming and going! But you can always opt for a regular soup base and enjoy it just as well. After two days in a row of this spicy stuff, we are taking a break tonight with some Peking duck (more on that later).

Sunday, December 23, 2007

Pictures from the past

The weather here has been awful for astronomy or pretty much anything else you could do outdoors. To ward off cabin fever I have been digging through some older pictures and picking the ones I felt could be improved with a little processing.
Here's one from the not-too-distant past. It was taken in October of 2006 at Brasstown Bald, Georgia. This is the highest point in Georgia at 4,784 feet. At the time I had just started using my Rebel XT with the Canon 50mm f/1.8 II lens. These are berries on a mountain ash tree:

Sunday, December 9, 2007

Outdoors with the WhiBal Card

Today I went outside and took some shots of what few plants still seem alive right now. OK, I didn't quite make it to the "great outdoors" but I did manage to walk out the back door, stand on the deck for a few minutes, and walk back in. What a shame being so lazy when it's 76° in December! It'll probably be cold and raining next weekend. Oh well...
We have some hen & chicks (or is it hens & chicks?) growing on the deck in little "mini rock garden" containers. Everything else has pretty much died off, but these little plants are doing just fine with almost no water.
First photo, cropped just a bit:

Next one, a full-frame photo:

Last one, another full frame:

These were all taken with my Canon Rebel XT and Canon 50mm f/1.8 II lens. I really love that little lens - very cheap and very sharp! I set the WhiBal card over one of the plants for the last image I took, then used that to set the white balance for every other image. The WhiBal makes my workflow extremely easy and efficient. I won't be leaving home without it!

Saturday, December 8, 2007

Photography with a modified DSLR camera

A modified DSLR camera is a powerful tool in the hands of any astrophotographer. Depending on the model, it’s a fairly low-cost method to obtain results close to that of the big, expensive CCD cameras that are made just for astronomy. You can save even more by doing the modification yourself. My first modification, as described in this post, was completed one year ago and I have done several more since then. My goal at that time was to have two cameras – one unmodified camera for normal photography and one modified camera for astrophotography. That goal didn’t last long once I realized the value of a nearly-new modified DSLR and needed some money to buy other astro equipment. Before long my unmodified camera was modified and quickly sold. After modding a couple more cameras and selling them, I was left with one modified Rebel XT. I installed a Baader UV/IR cutoff filter to replace the stock Canon filter in front of the sensor. This filter passes much more of the red spectrum, including the all-important 656nm H-alpha wavelength. This gives all images a red cast.
At first, normal photography was not a problem as long as I was using my X-Nite CC1 filter from MaxMax.com. This filter closely mimics the spectral response of the stock Canon internal filter and does a wonderful job of bringing the colors back to normal. Without it, my white balance is always wrong. But, as I have acquired more lenses and become much more interested in photography, the CC1 filter becomes more of an issue for a couple of reasons. First, my lenses have different filter sizes and it is inconvenient to change the filter with step rings if I need a quick lens change. Second, the CC1 filter increases my exposure time and makes hand-held photography in low lighting impossible without a tripod. It’s marginally acceptable with my Canon 50mm f/1.8 II lens – the only fast lens I own (because it’s cheap). My zoom lenses are f/3.5-4 at the widest, and I don’t want to spend a lot of money on fast zoom lenses.
I tried shooting without the CC1 filter and correcting the white balance when opening the RAW file in Photoshop. This works sometimes, but other times I just can’t seem to get the while balance right. Here’s an example of getting it right (or at least pretty close):

The left image uses the “As Shot” white balance setting in Photoshop RAW. A custom white balance was set from the inner lip of the white dish. It worked well in this case, as seen in the right image. Unfortunately I am not always going to get this lucky and find a nice neutral color in every situation. I could spend an hour trying to adjust levels and all sorts of other things to get the balance right, but I don’t want to do that on every photo I take!
I searched around on Google and read through dozens of websites discussing white balance. This seems to be a big topic of discussion for photographers based on what I found. There are so many products out there to help correct white balance, but which one to choose? After reading several reviews I finally decided on the WhiBal card from RawWorkflow.com. This little card is made of a neutral material that they check with a GretagMacbeth SpectroEye Spectrophotometer just to make sure it’s really neutral. It has a black & white label on one side that serves dual purposes – setting black & white points in Photoshop, and also telling you if you are getting glare by looking at the black portion (it’s reflective, so if it’s not black, you got glare). The WhiBal card arrived quickly and I immediately began taking some test shots. The WhiBal card is very compact and made of a sturdy foam-like material. It comes with a similarly-sized piece of black foam with a slot cut in it to serve as a stand. Also included is a lanyard with a quick-release clip and a carrying case made of very light material (feels like tent fabric).
The card takes a bit of getting used to at first. Finding the right angle to eliminate glare was tough at first, partly due to the so-so viewfinder of my Rebel XT, and partly due to shooting in a room with multiple light sources (overhead incandescent light and two windows). Below is a comparison of the “As Shot” white balance vs. the Custom white balance set from the WhiBal card:

The top image has the usual reddish cast that one gets from a modified camera. The bottom image appears natural and normal. Below is a comparison of the histograms from the Photoshop RAW editor. The left image shows the As Shot white balance with the red channel clearly exposed more than the blue and green channels. The right image shows the Custom white balance obtained by using the white balance eyedropper tool and clicking on the WhiBal card in the image. You’ll see that the individual color peaks are not aligned, but the image appears exactly as it looked to my eyes. The red channel is brought down and more in balance with the other two channels. As an experiment, I aligned the three channel peaks manually in Photoshop, but the resulting color did not look right at all. Therefore, I feel the WhiBal card performed perfectly.

Here’s another comparison taken in my wife’s sewing room. At the time this was shot, there was a mix of incandescent, halogen, and natural lighting coming from all sorts of different directions. Not the most ideal situation for the WhiBal card, or so I thought. I simply held the card right over the middle of the pens (where my camera autofocused the first time) and snapped a photo. I used this image to save a custom white balance setting in Photoshop RAW, and then applied that setting to my first image. Below is the comparison:

The left image is of course the As Shot white balance. The right image is the Custom white balance setting derived from the WhiBal card. So far I am pretty impressed. Next I'll need to get outside and see how the WhiBal performs in the great outdoors. I'll be sure to post my results here when completed.

Wednesday, December 5, 2007

Some other stuff....

As the change in my blog title reads, I am going to be expanding my blog from astronomy-only to pretty much everything in general. Astronomy will still be the main topic here, but I'd like to share some of my other interests like food, (non-astro) photography, and more food.
A few weeks ago we drove over to the parks around Lake Lanier, the reservoir that supplies drinking water to us and most of north metro Atlanta. The lake is just a mile from my house and many parks are close by. Due to the drought we have been experiencing since 2006, Lake Lanier has now reached the lowest level since it was originally filled with the water of the Chattahoochee River back in the 1950's. As of today it was around 1051-1/2 feet in elevation, a long way from the 1070 foot full pool level. Many interesting things are being exposed by the receding water, from old tires & fishing equipment to old house foundations and even a small racetrack. Unfortunately the racetrack is a long drive away (it's a big, big lake) but I'll get up there pretty soon. Back to our visit a few weeks ago - I took a lot of photos but I just wasn't happy with most of them. I am still learning a lot about photography and figuring out the right exposure, focal length, and composition. Here is one of the few (two actually) that I felt were interesting enough to spend some time processing in Photoshop:

I liked this one because a small tree is growing from the base of an old tree stump that should usually be several feet underwater. This was shot with my ultra-cheap Sigma 18-50mm lens that actually does a pretty good job. The raw image didn't look great, but after some processing I am pretty happy with the result. Keep in mind this is the first time I have ever tried to process a non-astro image in Photoshop.
The other image I felt was worthy of a little more processing was yet another tree stump. For some reason I find old tree stumps really interesting:

I think I might have over processed this image. But that's the good thing about saving things in Photoshop format - all my adjustment layers are intact and I can go back any time and tweak it. So far I am only doing a few simple adjustments like curves and levels on selected areas of each image. I try to work on each area separately and use masks to isolate whatever part is to be affected. Thankfully there is so much information out there and great photographers to learn from. Being out with the camera was a lot of fun and I can't wait to get out again. Hmmmm...I think I just got hooked on another expensive hobby!

Monday, December 3, 2007

"Starfinder" from DK Publishing

I was recently offered a copy of the book "Starfinder" from DK Publishing to review. I have quite a few Astronomy related books sitting around already, many of which are collecting a bit of dust right now. But it's always interesting to read something new, so I quickly accepted the generous offer. The book arrived and I was immediately surprised by the size. The "book" is actually a multi-functional case for it's contents. It is different & interesting with it's rounded shape, interior compartments, and a planisphere built right into the cover. While the size makes it stand out among other books, it is also slightly inconvenient since I don't have any shelves to accommodate it's 12+" by 12+" dimensions. I prefer the typical 8-1/2x11 size book, although making "Starfinder" any smaller would probably make the planisphere very difficult to read.
The cover opens up to reveal some how-to information for using the planisphere, as well as a guide to using the included constellation charts, found in little compartments on the interior of the book. Also inside the book is a small red LED flashlight. I must admit I laughed when first seeing this diminutive device, but it actually performs pretty well under total darkness. Most of us already involved in this hobby will have a good red LED flashlight, but for beginners this one will do just fine.
There are 44 double-sided constellation charts included made of sturdy high-quality card stock measuring 5-1/2"x3-3/4" each. They are divided up into 22 northern hemisphere cards and 22 southern hemisphere cards. Each card has a chart of the constellation showing the brighter-magnitude stars and Messier/NGC objects. There's a brief description of interesting objects which indicate if the object is visible by naked eye, binoculars, or telescope.
Tucked inside the back is a similarly-shaped reference book which is 72 pages long. This book is divided into three sections: Finding Your Way, The Solar System, and a Monthly Sky Guide. Finding your way has a lot of good information for the beginner explaining the vast distances involved in the universe, how our view of the sky changes with the seasons, basics of constellations, the mechanics of the solar system, objects of our Milky Way and beyond, basic info for getting started viewing, and an overview of "star-hopping." The Solar System section takes you on a tour from the Sun all the way out to Neptune, and even beyond that with comets, asteroids, and dwarf planets.
The final section is a Monthly Sky Guide which takes the reader month-by-month through the sky, describing interesting events & planetary positions over the next five years. A handy chart shows where the planets can be found among the constellations, and if they are in retrograde motion. The Monthly Sky Guide section includes information for both northern and southern hemisphere observers.
Besides the physical size issue I mentioned, my only other minor complaint would be the planisphere. While it is a very nice planisphere, it is built into the front cover and cannot be removed. I would love to be able to take just the planisphere outside without having to hold up the entire bulk of this book. Overall I found the content to be appropriate for the beginner while still being a handy guide for the seasoned observer. This book will give anyone a good start into astronomy without a lot of technical talk. The price is not bad either, just $18.40 from Amazon.com.