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Picture of Andy Krietzer
posted
Do your digital cameras auto focus, or are they focused on everything? I still use a 35mm film camera, and it is so hard for me to get what I want in focus. I have a number of different lenses, some for extreme closeups (down to 2" or so), a 28 - 70 mm zoom lense for normal use, and a @ 100 to 200 mm zoom lense for farther away. I wonder if digital cameras have the ability to zoom from up very close to a very long distance without changing lenses? What about focusing? I have used this camera for 20 or more years and still have not figured out a lot of the ways photographers can manage to either get one specific item in focus, or the entire scene in focus. I try to focus up close on a clock part, and something 1/2" closer or farther is out of focus. So how would I take a closeup picture of one piece of a clock movement and still get the rest of the movement in focus too? I rarely ever use a flash, I set the clock in a lot of light outside and use a white background.

Andy
 
Posts: 1190 | Location: Indiana in the U.S.A. | Registered: November 25, 2002
IHC Life Member
RR Watch Expert
Picture of Ed Ueberall
posted
We are looking at two different things here, closest focusing distance and depth of field.
Closest focusing distance is exactly what the name implies. It is the smallest distance between the object and the front surface of the lens that can still be properly focused by the lens. Many digital cameras can focus down to less than 1", without adding closeup lenses. A short minumim foscusing distance is am important consideration when choosing a camera to photograph small objects such as watches.
Depth of field is a different term and refers to the closest and furthest distances that will still be in focus at a given lens aperature. The smaller the aperture, the greater the depth of field. To increase depth of field, choose a small lens aperture (or a higher f/number). This will require a slower shutter speed to still let in the same amount of light needed to make a proper exposure. All of the above holds true for both film & digital photography. It also explaines why the best photos are taken using a tripod or copyboard so that very long exposures can be used with very small aperatures to maximize the depth of field.
The other thing to remember is to set your focus (with the aperature wide open) to the mid point of what you want to be in focus. Then when the lens is stopped down, the area in focus increases both closer and further way from that cental point. As an example, suppose that with a given lens wide open, everthing between 6 and 8 inches away is in focus. If you set the distance setting to focus at 7 inches and stop down the lens everything between 4 and 10 inches may be in focus.
When I am photographing watches, I usually set the camera to manual focus and focus on the gears between the plates, then when I stop down (by setting the camera to aperature priority) the entire movement from the barrel bridge to the pillar plate will be in focus. Usually for maximum resolution stop your lens down to 1 to 2 stops from the smallest aperature available, as some lenses do not work well when stopped down as far as they will go.
For film work, the best lens to use is a fixed focal length designed for close-up work. These have a small minimum focusing distance and give better resolution than zoom lenses. But the real key is to stop down the aperature to get the depth of field that you need.


Ed Ueberall
IHC Member 34
The Escapement
 
Posts: 622 | Location: Pooler, Georgia in the U.S.A. | Registered: November 23, 2002
posted
Andy, I use a Digital Nikon D70 with 28 - 70 zoom. After some trial and error, I found that the best photos I take used the on-camera flash in commander mode and two offset slave flashes positioned to each side (one free standing flash positioned on a tripod that I bounce off an umbrella directed at the clock, the other free standing flash bounced off the ceiling). I set the aperture to try and get sufficient depth of field. It seems to give me the photo depth that I find personally appealing.

You may want to look into obtaining a digital camera body only since you have detachable lenses. When I looked into digital, I went with Nikon because I had some Nikon lenses and they could be used with the D70 body. I use the Autofocus feature of the camera, but I try and get as much depth of field as possible to correct for any of the autofocus feature deficiencies. I can't say for sure, but I believe this is also true for Cannon and maybe some other manufacturers.

I like digital because I can get some immediate feedback about the picture I've just taken (exposure, composition, etc.) Once downloaded to the computer, there are several programs that can be used to adjust, resize, crop and enhance your picture. I use Adobe Photoshop elements, but there are several very good ones that are probably simpler and more users friendly. Hopefully this is some useful information.

Derek Phelps
 
Posts: 172 | Location: Lexington, Kentucky U.S.A. | Registered: July 06, 2004
posted
Andy,
If your camera is a SLR, it probably views through the lens.
The amount of foreground and background in focus depends on your f stop. With a high f stop (narrow aperture), you will have quite a bit of foreground and background in focus. With a low number f stop (wide aperture), you will have less foreground and background in focus. The amount of picture in focus is called depth of field.
I have found that focusing SLR cameras can sometimes be frustrating. If you wear glasses, you should probably use them when taking pictures. Under critical conditions (short depth of field/low f stop/close up/relative low light conditions) you can automatically compensate for the error in your eye and focus either further away or closer than planned. If you cannot wear your glasses to take pictures, you may be able to buy an auxiliary lens for your camera that will correct for the error in your eye. Be mindful that both your eyes do not usually take the same correction. If you buy an auxiliary correction lens, you will have buy a lens to fit either your left or right eye. Then make sure you always use that eye for focusing the camera.
One of the big advantages of most digital cameras is the auto focus feature. Most better cameras can be set to focus a point on the screen. This point can be adjusted to anywhere in the frame. The camera can also be set to focus on a rectangular portion of the frame, usually set in the center of the frame. (This is usually the default setting). Some cameras are not capable of focusing any closer than a couple of feet from the lens. This, for watches, details or small parts simply won’t work. More expensive cameras will focus within an inch or so of the lens. One usually has to spend a few more bucks for the bells and whistles.
Most digital cameras will be sold with both digital zoom and with optical zoom ratings. In my book, you can forget digital zoom. Digital zoom is merely taking the center out of the frame, ignoring the outside border. It is like taking the Mona Lisa and cutting out the center of the painting, throwing away the border. Optical zoom is what is important. Optical zoom acts like the zoom lens you are used to. Not too many years ago, zoom lenses were frowned upon because of loss of quality in the perimeter of the lens. Vast improvements in lens design have been made and now zoom lenses are preferred over single length lenses. If you are contemplating a digital camera, spend as much as you can for optical zoom.
There are a few other variables with digital cameras. One is the storage device (These could be paralleled to what we used to call film). Some storage devices used in cameras can be used in other electronic devices. Some storage device styles are bound to fade away like the Sony movie recorders. Same is true of some battery styles. As digital camera design has advanced, they have added more mega pixels. The more mega pixels, the better quality the camera is able to produce. (We used to call poor quality pictures grainy and high quality pictures fine grained) Highly grainy pictures usually come from excessive enlargement, both with digital and film cameras.
For kicks, visit your local camera store (leave your check book, credit card and billfold at home) and ask the sales people for a test drive of what is on the shelf. Usually they are more than happy to demonstrate.
 
Posts: 311 | Location: Berthoud, Colorado USA | Registered: December 08, 2002
posted
Lots of the foreground and background in focus. Taken with a high f stop. Twilight peaks, between Durango and Silverton, Colorado, in the Four Corners area.

 
Posts: 311 | Location: Berthoud, Colorado USA | Registered: December 08, 2002
posted
Very little of the foreground and background in focus. Taken with a large f stop. Colorado Columbine, our state flower.

 
Posts: 311 | Location: Berthoud, Colorado USA | Registered: December 08, 2002
IHC Member 376
Watchmaker
Picture of Samie L. Smith
posted
Andy if you want a ditigal camera that is user friendly get a sony ,a Nikon is good also, these have both automatic and manual modes..you need one with a macro mode ,,also i would not buy any digital camera without a steady shot feature..The camera i use will take great pictures at longer distances and up as close as 2 inches..

The camera i use is a sony fd95 it cost 1100.00 in 1999 you can now buy a camera that will do as good and even more than mine will for less than half that much..

here is picture taken freehand with no special light using the steady shot feature and on macro mode at about 2 inches distance..

 
Posts: 3206 | Location: Monticello, Kentucky U.S.A. | Registered: June 24, 2004
Picture of Sam Williamson
posted
Great shot Samie! What size file did you use?


Sam Williamson

 
Posts: 619 | Location: Northwestern Florida in the U.S.A. | Registered: November 27, 2002
IHC Member 376
Watchmaker
Picture of Samie L. Smith
posted
Sam this picture was taken on a 640x480 setting on the image size, using macro mode and steady shot..when i downloaded it to the computer it was ready to email or post up,, the file size of the picture is 39k...
 
Posts: 3206 | Location: Monticello, Kentucky U.S.A. | Registered: June 24, 2004
posted
quote:
m

quote:
Do your digital cameras auto focus, or are they focused on everything?


The way Auto focus works is that camera is looking for areas that have contrast. If you are trying to focus on an subject that has similar colors, it will search for focus.

The camera also has an AF sub mirror behind the main mirror if you're using an SLR. If you lift up the main mirror behind the main mirror is a smaller mirror, if that mirror gets dusty, you will have problems with autofocus. You can clean the AF sub mirror by dabbing a little windex on tweezers wrapped with some kimwipes.

If the AF still has problems, use the manual focus mode.
 
Posts: 4 | Location: San Diego, California in the USA | Registered: January 21, 2008
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