Zone Focusing ?

[MT Net]

Back in the days of film SLR photography, I vaquely remember a trick called zone focusing. That was back in the early 1980's. Since, my mind has been awash in digital stuff from point and shoot to now a DSLR.

Autofocus begins to fail as the light conditions darken, making it more difficult to focus in low light / night photography.

The film SLR camera lens used to have an aperture ring and a distance right on the lens housing. Also, there were all these converging lines and graphs on the lens barrel as you zoomed in or out. Not so on our modern DSLR lens.

Is it possible to zone focus with a DSLR? Rather, how is it done without the distance range meter?

BTW, I did a search on this forum and didn't find anything, sorry if this was already discussed.

[Dbl]

Whoa, you are bring me waaaay back! I used to do that years ago as you mentioned. I used this system mainly for sports but some wildlife shooting as well. I just checked a few of my lenses and they indeed do still have distance rings. So in theory you could still use that system.

Part of the problem is todays cameras do not have the viewfinder system or the focus screens that we used to have. They are very difficult to do any manual focusing on. The viewfinders are dim and small. The focus screens don't have the brightness or the focus aides like split circle, etc.

Todays auto focus can auto focus in lower light if you have a good fast system, think Nikon D3 or Canon 1 series cameras. The lens you use also makes a difference. The faster lenses will do much better in lower light than a consumer grade lens. You also can use an option for focus assist on the lower cameras, it uses your on board flash to focus assist.

Embrace the new technology, I sure don't miss the days of manual focus!

[Jim Almquist]

If you want to manual focus there is a company or 2 that makes a lens or focus screen replacement. Just google haoda manual focus screen and see if that is what you are looking for.

[Paul]

Quote:

Embrace the new technology, I sure don't miss the days of manual focus!

Oh man me neither. I still remeber the horrible results I would sometime get when shooting my Minolta SRT101 fully manual SLR camera. 1966 model. The camera was passed down to me from my father when he bought a new one in 1982. I shot my first few thousand prints using a fully manual, manual focus, maual film advance manual flash bulbs etc. I thought I was pretty high tech when I inherited a shoe mount battery operated flash. (which I now use soley in my fish house to light glow jigs.)

Cameras have come a long ways.

[Dbl]

I know there are focus screens out there to help with manual focus but you still have the viewfinders that are just dim and small compared to the manual focus days. Its the combination of the two that made it relatively easy to manual focus.

[MT Net]

With my Canon XTi, I find the autofocus will not work on my 17-85 mm and 70-300mm lens in low light conditions. The autofocus searches, but will not lock in.

This shot below had to be on manual focus on the bird. The Mississippi River was flowing a bit, the autofocus could not pick up either the bird or red light in the river. I had to work fast as the bird kept moving. and manual focus is nearly impossible in this dark of conditions. Maybe this is a problem with the XTi, or, at least mine.

Lens: EFS 70-300 USM IS Exposure: 1.3 seconds, f5.6, ISO: 800, focal length 300mm, manual focus.

By the way, I discovered this bird in the shot below while viewing the LCD to see how sharp I was able to get the image.

Lens: EFS 17-85 USM IS Exposure: 13 sec, f11, ISO 400, focal length 38mm, auto focus center weighted on the bright light of the building. I chose f11 for greater depth of filed, but unfortunately, the Wells Fargo Center is blown out.

[Steve Foss]

MT, auotofocus requires contrast to function, and since low light usually means low contrast, it frequently will hunt for focus. The less advanced the body and lenses, the more hunting will go on.

You did a nice job on the manual focus. Sweet image.

In the cityscape, it wasn't the f11 that blew out the WFC. Unless you were on manual settings, the meter was fooled a little bit because the very bright spot made by the building is a small portion of the overall image. In metering for proper exposure, your meter wasn't able to see how bright the building was because it was so small. To compensate, using your camera's exposure compensation feature to underexpose would have been the way to go. A look at the histogram on the back of the camera would tell you how much to underexpose (the overexposed areas stop blinking when the compensation is right).

That would have produced an image with more noise because there would have been darker shadows because of the overall underexposure, so you would have to deal with brightening the image and then reducing noise in post-processing.

[Dbl]

The Xti and that lens combination is not known for it great focusing ability in low light. See my initial response to your post.

This picture look familiar? By contrast I think my settings would have been ISO 100, f8 and 10 to 15 secs.

[MT Net]

Steve, I'm shooting strictly manual mode. something I wanted to do and learn by trial and error since purchasing this DSLR. 95% of the timeI shoot manual, 5% in AV, forcing myself to get a handle on how this all works together. Now to learn exposure comensation and how that works.

Ah, I see what I've done in comparison to your image, Dbl, I've overexposed my image to be too bright. The sky is overly bright with more noise.

The fun is to revisit and re-shoot these images after learning from the mistakes made.

Thanks again, you all have been a great help to novices like myself.

[Steve Foss]

Manual mode is a great deal. Glad you've dedicated yourself to mastering it.

[Dbl]

It really is what you want to capture, neither one of these photos is "correct". What are you interested in retaining, more detail in the buildings, preserving some of the bright lights? Its up to you.

That is why I take a number of different exposures and vary the time, I may not know which one works for me until I see it on at home on a computer screen.

Digital sensors do not have the latitude or range of exposures possible like film does. So it is harder to capture these dynamic ranges in the scenes. That is where post processing can help.

HDR, dodging and burning, working in layers they all help extend the range of what the camera can do compared to what our eyes can see.