Archive for the ‘Articles’ Category
The Perseid meteor shower for 2008 peaks in the morning hours of Tuesday, August 12th. The best views will be after 2.00am when the moon sets.
This is called the “Perseid” meteor shower because, from our view, the meteors seem to come from the area in the sky which includes the constellation Perseus. This constellation rises around 11.00pm and will be high in the northern skies all night.
If it’s a good shower, you might get to see sixty meteors an hour.
What you need to observe them:
Darkest skies possible. If you can, get as far away from the city (and any lights) as you are able.
Despite it being summer, it gets chilly late at night. Bring a jacket, blanket, etc.
Bug spray. Skeeters love to bite.
You can either bring a reclining lawn chair or lay on the ground, it’s your call.
(We always bring some tunes, plus snacks and drinks).
Bring a red-filtered flashlight. The red light won’t ruin your night vision like a white-light will. You want your pupils to be as dilated as possible to see as much of the sky as you can.
Some photography tips (since this IS the topic):
Use a semi wide-angle lens. Not too wide, because the meteors will look really tiny in your images. If you have a crop-sensor camera, nothing wider than 28-35mm.
Use manual focus, and make sure you are focused on the stars. That means infinity. Now, I’ve found that lenses for DLSR’s have a “range” for infinity focus. Just turning the focus ring all the way to the infinity stop won’t work. If you can, focus on a radio tower or some other bright objects far away. If you can focus on a star, that’s even better (Live View works great with this). Take a few shots and look at the image on your LCD screen, zooming up to see if the stars are pinpoints.
Because the stars move across the sky during the night, you will get star trails. Keep you exposures to around 5 to 10 minutes or so. This means you will more than likely need a remote release. :)
Point your camera in the general area towards the north-northeastern sky. As the night goes on, you might want to shift where it is pointed. The closer you are pointed to the radiant (where the meteors appear to emanate from) the shorter the meteor trails. Also, if you notice an area where meteors are more frequent, you can point there. Try different areas of the sky.
Start with an ISO of 400. If you can, and your camera gives good results, you can boost it to 800, but I wouldn’t go any higher.
Shoot as close to wide-open as you can. I would suggest ½ stop smaller than your widest aperture. Many Perseids are faint, and you need to wide-open aperture. Yeha, there are really bright ones as well (I saw a really bright one last night while imaging the moon).
If you get one or two going through the field of view (you think), just stop the exposure and start a new one.
Use NR at your discretion. Remember, if you take a 10 minute shot, you will get a 10 minute NR exposure as well, so you’ve wasted 10 minutes. You can always do your noise reduction during post processing.
Watch out for dew! Depending on how much humidity is in the air, your lens will dew/fog up. Have some way to clean off the lens.
Make sure your batteries are fully charged.
Have a nice sturdy tripod.
Since its inception, photography has been used to inform, spark debate, and conjure emotions. Single photographs have been used as catalysts for change in foreign policy and in some cases, war. If no photos of the destruction on September 11th, 2001 were published, would we currently be fighting the war in Iraq? If a photo is worth a thousand words, how many words is it worth if the photo has been retouched? Today, more than ever, this needs to be kept in mind as the ease of digital photo manipulation has become all too tempting. Only a few quick adjustments can make a spectacular photograph out of an ordinary image. Continue reading
While many alternative photographic processes date back to the beginning of the last century, there are a few that are still in their infancy. The advances in digital photo editing and inkjet printing have introduced us to a whole new world of hybrid processes, using both traditional film and darkroom based photography in conjunction with these new digital tools. Most notable of these processes is the creation of negatives from a digital file. These digital negatives are produced by manipulating a source image digitally, whether it is scanned film or from a digital camera, and printing it on a transparent or opaque material for contact printing in a traditional darkroom. Just about anybody can print a decent quality photo from their inkjet printer, and many of you know your way around the darkroom quite well, so it would seem that bringing the two processes together would be a simple task. This couldn’t be any farther from the truth.
In 1949, when Bocour Artists Products marketed the first acrylic-based paints, many artists were eager to experiment with this new medium. Although they were easier to work with, were much more durable, and easier to clean up, the artists themselves and the schools in which they were taught never gave up on traditional oil-based paint. The recent technological advances in digital photography have caused many photographers to shelve their old film-based Nikons and Hasselblads for the ease and instant gratification of digital photography. This ease and instant gratification has also resulted in more and more people who always wanted to try photography but never had the time, indulging in photography as a hobby. It’s hard to see a downside to this, as it has spurred growth in the photography community, given struggling photo companies new customers, and increased enrollment in photography schools. The downside is there though, and it is affecting those who still remain true to film and have not given into the hype of digital. Film and the necessary chemicals for development have become harder to find and have risen in price, more and more lenses are being designed only for digital, and worst of all – colleges and photography schools, such as Grand Rapids Community College, are replacing traditional film based courses with digital alternatives. While each format has it’s own unique benefits, there is still no substitute for the clarity, tonal range, and aesthetics that silver-based film photography offers.
“The Polaroid image transfer process relies on the ability of dyes in the Polaroid emulsion to migrate to an alternative receiver surface during the development process. The “normal” Polaroid process is interrupted and the “negative” is placed on another material (usually paper). The dyes that will form the image are encouraged to transfer by the use of heat and pressure. This process was accidentally discovered when a Polaroid negative was left sitting on a lab counter, according to legend!”
More information on Polaroid Transfers:
– Brad Gillette
The Sabatier process is often mistakenly referred to as “solarization.” In actuality, these are both distinctly different processes. Solarization occurs while the film is still in the camera. It results when film is overexposed to the point that the silver halide crystals have been completely saturated with light, which means it has reached “gamma infinity”. When this occurs, the crystals with the most exposure begin to reverse themselves. A good example of this is in a print where while everything else appears normal, the sun is a deep black. The Sabatier process however, is done entirely during the printing stage, with no special exposure of the film necessary. In the simplest of terms, it is when you re-expose the paper with light halfway through the development process. This results in the darker areas of the final print being rendered as normal, while the lighter areas are reversed.
I have been experimenting with Rollei’s R3 black and white film, and have so far developed two rolls. One at ISO 200 in their Low Speed Developer, and the other at ISO 400 in their High Speed Developer (Amalco AM-74). So what are my initial impressions?
Going through the stats of this blog and seeing where people are coming from, I noticed that Docksidepress searched for photos of his that were blogged on others blogs. Lo-and-behold, there were a few spam blogs using his photos on their sites. I’ve ran into this myself with photos from my sewer backup. But what can you do about it?
Now, at this point, I need to make two things clear..disclaimers if you will.
1) By sending a photo to the grand rapids flickr group and allowing blogging, you are letting us use that photo on this blog, either through the flickr widget, as a pick of the day, or for articles. If we have done this and you DON’T want us to use that photo, PLEASE let us know and we will remove it immediately.
2) I am not a lawyer , nor do I claim to be, so take this advice with a grain of salt. If someone is a lawyer and wants to correct this for me, please let me know.
The SLR.The single-lens reflex (SLR) is a type of camera that uses a movable mirror placed between the lens and the film to project the image seen through the lens onto a matte focusing screen. Most SLRs use a roof pentaprism or penta mirror to observe the image via an eyepiece, but there are also other finder arrangements, such as the waist-level finder or porro prisms.
The shutter in almost all contemporary SLRs sits just in front of the focal plane. If it does not, some other mechanism is required to ensure that no light reaches the film between exposures. For example, the Hasselblad 500C camera uses an auxiliary shutter blind in addition to its in-lens leaf shutter.
This feature separates SLRs from other cameras, as the user sees the image as it would be captured. This aids in accurately knowing the image beforehand.
Since the technology became widespread in the 1970s, SLRs have become the main type of camera used by dedicated amateur photographers and professionals.
So what makes the SLR the main type of camera used by professionals? Ease of use, the ability to change lenses, being able to see what your photo will look like through the lens, the ability to control what happens….the list goes on and on, so I’ll stick with the main points.
Ease Of Use
SLR’s might look confusing, but they are actually very simple. You choose what lens you need – a lens that has been designed to do what you need it to do – you set up or find your lighting, you set your aperture for the effect you want, set your shutter to compensate for your aperture, and press the shutter button.
Does that still sound complicated? Its really not. Today’s SLRs and dSLRs (Digital SLRs) now include an Auto Mode that works just like a point and shoot, yet still gives you the ability to decide what kind of special lens is needed to get that photo that you want.
For myself, I primarily keep it on Aperture Priority Mode. I like choosing what will be in focus and will not, and primarily stick with a large aperture (large aperture = low number, 1.8, 2.8, etc.) so I can separate the main subject from the background. We’ll cover that in a future article.
From wide angle, to “normal”, to extreme telephoto, the ability to switch lenses is enough to warrant the purchase of an SLR, which can now be purchased for the price of a medium / high quality point and shoot. But there is an investment to be made. One problem with SLR’s is that lenses arn’t compatible among the major brands. You won’t be able to fit a Canon lens onto your Nikon or Sony body, nor will you be able to put your Nikkor lens on your Canon or Pentax body. Nikon (Nikkor lenses), Canon, Sony, Pentax, and all the other brands have their own standard for their lens mounts making switching from one to another a near impossible task unless your made of money. Once you’ve invested in a particular brand, that’s the brand you’re going to stay with unless you REALLY want to switch. And within the brands, there are often different kinds of lenses made for different types of cameras. Nikon has been good with this, and any lens made in the last 60 years will at least mount to the Nikon body, though you might just loose your exposure and auto-focusing ability. Canon on the other hand has changed their mounts quite often and in a few cases, a lens you bought for your canon film body might not mount onto your digital body.
(The ability to see what your photo will look like before you shoot.)
The older point and shoot cameras had a little window on the front, and when you looked through the viewfinder you were looking through that little window. You didn’t see exactly what the camera was going to see, and this was a major problem for pro photographers. Nowadays when you look through the viewfinder of an SLR camera, you are looking through the lens seeing the exact same image that your film is going to see.
A lot of the modern point and shoot digital cameras nowadays give you the option of changing the shutter speed and/or aperture, but that’s about as far as it goes. The higher end point and shoot models will give you even more options to take control of your photography, but are still limited. SLR cameras are exactly the opposite. Instead of making everything automatic and then adding in manual features, they give you complete manual control right from the start. In addition, as the prices of SLRs have dropped the manufacturers have started adding consumer friendly automatic features.
Realistically, there are only three basic settings that you need to watch – shutter priority, aperture priority, and manual priority. Of course you also need your aperture ring or dial, and your shutter dial or knob. That’s it. Everything else is just fluff and any kind of effect can be achieved using these three settings, along with the focus ring.
These days the higher end point and shoots are becoming more and more like their SLR brethren, while the lower end SLR’s are dumbing down more and more to become their point and shoot cousins. Either kind of camera will function for you, just know what your needs are so you can make a wise decision before you buy.
There are many many other kinds of cameras that I’ll write about later, including Polaroids, large format, medium format, rangefinders, video cameras, cell phone cameras, toy cameras, 3-D cameras, etc. As long as light is hitting a form of film or a light sensor, it is a camera.
I really hope that these two articles have helped you with your camera decision or helped you understand more about your camera choices. These articles are not perfect and I will be editing them along the way as my knowledge about cameras continues to grow.
Use the comments section of the blog — If you have noticed any mistakes, please let me know, if you want to debate, let me know as well, we’ll make it public, and a good debate is always good. If you have any questions, don’t hesitate to ask, that’s what I’m here for.
Written by FD on Photododo
A brief history lesson about an image sharpening method called “unsharp mask.” Photoshop and other image manipulation software all have a feature with this name that will sharpen an image. So, why is it called unsharp mask?
The name comes from the original photographic procedure used to increase the apparent sharpness of a photograph on film. First the original negative was copied and turned into a positive (In a negative, black is white and white is black. In a positive, it’s the other way around.). During the copy, the positive was intentionally blurred. This is where “unsharp” comes from. Then the positive and negative were put in contact and exposed to light again. The blurry portion of the positive cancelled out (masked) the blurry portion of the negative.
Despite working with bits instead of film, digital unsharp mask works similarly by comparing the source image to a slightly blurred version and subtracting one from the other.