TKSeminars

1. How does one best shoot a photo through glass, such as an aquarium? or a net? or a chain link fence?
   

   You can purchase a polarizing filter to reduce glare when shooting through glass, but your results will depend on the kind of glass, thickness of it, etc. Your best results can be had when the lens is flush with the glass. Whenever this is not possible, getting as close to the glass as possible would be your next bet. If you’re going to shoot with the macro mode on, you will have to watch what you’re focusing on, since you could easily focus on scratches, dirt or algae on the glass itself and not even know it!

   Shooting through a net or fence - well the answer to this depends on how artistic you would like to get. If you focus on the net intentionally to produce an interesting foreground/background effect, you could end up with some cool photos. Alternately, you could focus on the background objects and have the net/fence provide a fuzzy foreground haze that could add an interesting dimension to the overall composition. If you want the fence or net out of your shot completely, you’ll have to make sure the camera lens is shot through the net or fence without it being an obstruction in the image.

   Finally, with lots of practice, you’ll probably stumble upon some techniques not in this response.

2. What is the difference between optical and digital zoom and how to use them?

   In essence, optical zoom is the zoom power of the physical lens, where digital zoom is the in-camera ability to “crop” into the image so you have the appearance of zoom. The former uses the full resolution of the camera, whereas the latter decreases the resolution of the final image.

   Here is a quick example to think of : say you have an 8.5×11 piece of paper with a photo of a cat on it in the center of the image. Let’s say you cut 1″ off all sides. You now have a 6.5×9″ paper, but the contents of the image now appear a little bigger, since what’s left has less space around it. The cat seems to have gotten closer, but the paper got smaller. Now take that reduced image and blow it up to 8.5×11. You might notice the quality has been lost in the blow up. This is digital zoom. Your image resolution will drop, but the object will appear to fill more of the frame. Optical zoom, is the equivalent of moving closer to the subject with the full zoom power of the physical lens and printing that image on the full 8.5×11 paper

   Generally, digital zoom is not recommended unless you absolutely can’t get the shot any other way or you’re happy with a lower resolution final image.

3. You had mentioned mpix.com and ezprints.com as sites where we could order panoramic prints. Do you like one of them more or is one more economical?

   Also, I thought you had mentioned a software we could download (for free?) that would stitch our panoramic pics together.

   Where do I find that online? Then, does it give you a file you can manipulate in photoshop? Does it give you a choice of format?
   

   In terms of ezprints vs mpix, here are some things to remember :

   • ezprints will print panoramas 12″ tall and up to and perhaps exceeding 60″ long. I don’t believe mpix has that capability - they do 10×20 only according to their website. You could however order a 20×30, print a 10×30 on it and then cut the white space out when you get the image.
   • the tool we mentioned in class is call autostitch. You can find it here
     : http://www.cs.ubc.ca/~mbrown/autostitch/autostitch.html.

     It is PC only and is pretty bare bones, no frills. It will create JPGs only, which are usable and editable within Photoshop. There are a lot of other tools out there varying in complexity, and a good place to browse for more information ( and get a little inspiration ) is http://www.panoguide.com.

   Some of the commercial tools let you save the file in other formats like BMP or TIF and load them into Photoshop. I find JPGs at the lowest compression setting sufficient for any final editing I will do in Photoshop.

4. I suspect I’m shooting at 400 ISO too much (which I do sometimes to let in more light to get rid of the shake warning my camera gives me), but this lets in noise. How should I deal with this?
   

   ISO 400 may be the right setting for the exposure you’re trying to get, so don’t stop using it. You have a two broad options : hardware and software. On the hardware side, you can get a good tripod and shoot the image as ISO 100 or 200, if it makes sense to do so Another option is to check the manufacturer’s website for your camera. Often times they post firmware upgrades for your camera that may improve a particular feature. Sometimes, noise performance ends up making the list and is implemented as a firmware update. Check the website support/downloads section to see if there is an update that might address this. Another option is to use external flashes Depending on the subject, shooting conditons, etc. more light on the subject may allow you to shoot at a lower ISO. You could also consider other factors like aperture. You can, for example, get the same exposure at ISO 200 by doubling the amount of light ( lower f-stop ) exposed on the sensor Of course, a last resort is to consider a new camera. I know there are newer point and shoots that have improved ISO 800 and even 1600 performance If your photography is getting more serious and you experience the limits of you camera more frequently, consider a DSLR. Fuji, Canon and Nikon make cameras that have excellent noise performance any great pricing starting around $600+. See http://www.dpreview.com for loads more info.

   Software that can help you will come in the form of either a standalone application or a plugin. I know that there is a plugin for Photoshop called Noise Ninja. That tool seems to get rave reviews for generating excellent images while reducing noise substantially. It may also be time to consider upgrading to Photoshop Elements, Lightroom or CS3.

   You also need to realize that each time you open and re-save a JPG you are recompressing it. This means that if you open and save a file 10 times, it will have been compressed 10 times. Compression works by reducing the iimage size so that the image looks perceptually the same, but does not have all of the original data. So a compression artificact is just a portion of the image that not longer tricks your brain into believing the portion of the image is similar to the original. You can notice these artifacts more visibly when you use high compress/low quality. They will usually be splotches or blocks of color and may even make the image look fuzzier. The best thing to do when editing is save the image in a lossless format like BMP or TIF. Of course, if you get Photoshop, you will not need to do this since it saves images in the PSD format - saving you the hassle of storing it as BMP/TIF. Only when you’re ready to ship the final image will you save it as a JPG. A final note : oversharpening can also degrade the image.

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