My question is this- For the perhaps "average" railfanning user, how much zoom is truly useful or functional? For example, how much difference is there between a digital video camera that has a 20x optical zoom and 500x digital, versus one that has 35x optical and 2000x digital? Obviously one can "reach out" further than the other, but is there really that much gained? Where is the limit to video quality and usefulness? Boxcab E50
Digital zoom is BAD zoom! Instead of making the subject appear closer (among other things) as an optical zoom will, the digital zoom increases pixel size to fake a larger image, but very poorly. Here's some clear reference: As far as usefulness of the optical zoom (focal length), there are a variety of ways focal length comes in useful. You can get real close with a small focal length to make a locomotive appear highly distorted and dominating. Or you can increase the focal length and choose an angle with a distant background to get selective focus (background goes out of focus). Or you can back up with a short focal length and get everything in focus. All these effects wont be near as controllable on a camcorder as they would on an SLR camera, but it's mostly the same principal. And none of these can be enhanced by digital zoom. D-Zoom will only (and destructively) increase the image size. I'm taking a digital photography class at the Academy this semester and though I'm getting flooded with knowledge, we're not even scratching the surface of the world that is photography/videography. So in an nut shell, completely ignore the digital zoom specs. Focus on the specs that are far more important (sensor size/quality, optical quality, focal length, output format.. ect. ect.)
Boxcab50, One of the tenents of photography for beginners and intermediates is to turn the digital zoom feature OFF in our cameras. Even most of the manufacturers state this concept in the directions. Mark's illustrations show the rapid decline in picture quality when digital zoom is used. Back in the day when digital camers where new, total zoom power was a selling point. Now most of us have confidence in ourselves and can make a camera buying decision without regard to this 'black hole' of digital cameras. Hopefully no one falls for the grand total zoom advertising anymore. It is optical zoom we are looking for. Some folks think I can take an ok photo and one of my tricks is to use even the optical zoom sparingly. Maybe just to get the fascia out of the photo or something like that. If I need to get really close I use the macro. Actually, I can remember a macro photo I've taken in a long time. For zooming purposes I use my 8 year old photo program I bought for $29. Basically my secret to zooming is to take the photo from a reasonable distance using my favorite megapixel settings, then use this old photo editing program to 'Crop/Trim' my photos. I leave any zooming out of the equation. Works for me. For video it seems most cameras don't allow you to 'turn off' the digital zoom. I make a conscious effert to never exceed the normal optical zoom. Under almost all video circumstances I try not to use the zoom feature at all. I move closer or farther away from my trains if I can. Once again image quality suffers anytime any zoom feature is used. Jim
I have taken advantage of Digital Zoom for the extreme long shots that I would not have gotten otherwise via Optical; but, as stated it wll get a bit blurly if you try to get a close up shot. I'm looking to move to a Prosumer video camrea this year and I am quickly finding how limited of Optical Zoom they have compaired to the non-HD versions. Look for that "vertcail line" in the zoom indicator as that is where Optical/Digital take over begins and you will quickly see the bluring for close up shots but not as noticable for distant shots until you are shooting exteme distiances. Short Video with 300X Digital
Here is another short video clip that shows digitial zoom that optical would not have worked but again, it's for extreme long shots that optical is just not ment to get.
Nice examples of where digital zoom works, Darren. I stay away from it, as the others, in everyday / layout photography. One other key to "zooming" by cropping is to ensure the pixel density in the original is as high as possible. For most display on the fora, for example, you don't need that much density (photos are limited to about 600K pixels), versus the 10 Megapixels common in digital cameras.
Interesting information. I am used to my digital camera, and do fine with those stills. But the video camera aspect I have not paid any attention- Until now. One that catches my eye, keeping in mind if I can get one some day soon, I am on a very (very!) tight budget, is the Canon Vixia HF R10. Is anyone familiar with this item? If so, what shortcomings, if any, for Joe Average railfan and his personal enjoyment? Boxcab E50
Ok, jumping in quite late. I do a lot of video but, it's not rail. When I purchase a video camera I always look for the highest optical. A lot of people get fooled into going for the highest zoom which isn't very good as stated above. It gets so pixelated that you can barely see what is happening. As with photography, try to get as close to the subject as possible. I can get my video camera right up to the digital zoom but, I try to never cross over into it.
For we who are less educated on camera abilities, could you discuss "highest optical?" What do I look for in the specifications sheet, which would be helpful in that regard?
Oh, that is an easy one. When a camcorder lists it's optical rating, like 20x or 30x go for the the 30. It means it can zoom further before it hits digital zoom. Different camcorders go with different optical settings. Some will put in a better optical or digital zoom and limit the space that it can save to and vs. versa. I use a sony hd mini dvd camcorder with a 40x optical and a 2000x digital zoom. The digital is worthless to me mostly. I bought it because, of the optical zoom of 40x. I also like the mini dvd's. I can swap them out and put in another one instead of having to download a fixed harddrive camcorder. Most adds for camcorders will specify what their optical zoom is in the add and you don't need to go digging in spec. sheets for it.
