How do I focus my Pentax Asahi?

[brandy_moore1]

I have a pentax Asahi K1000. I have taken tons of pictures with it.

I have recently been looking through this website and have seen

better focused photos than mine. I can focus on an object and it

will be clear but the forground and background will be out of focus.

In the photos that I see here, everything is in focus. How could I

get my camera to do that?

[walter_degroot]

depth of field

the wider your aperture the shallower the area that will be sharp

you view and focus at f/1.9 ? f/2.0 ?

if you use a fast shutter speed the lens will have to be open at f/1.9 . f/2.8 or f/4. if you use either faster films or a slower shutter speed, you will use a smaller aperture such as f/11 or f/16

and the depth of fiels will be greater.

there is also a term called " hyperfocal distance"

i generaly under stand it but will let others explain it.

it is also possible that your lens is stuck wide open.

[stemked]

It is a pitty the K1000 doesn't have a 'depth of view preview. There is a way around this. As noted by the other poster you'll need a 'faster' lens. Also some lenses have a nicer soft background blur than other lenses. But to preview from a K1000 you'll need to be working from a tripod. focus on your subject. Now begin to take off the lens while you are looking through the camera (obviously supporting the lens. There is a point where the lens will stop down to the aperture you've set. That is how the image will appear.

[stemked]

The hyperfocus Walter is talking about is a technique to use selective focusing when you don't have a DOV knob or do not want to loosen the lens like I explained. You can really only do this with lenses that have special markings on them. Fortunately, most Pentax prime lenses have these marks.

 

Take one of your primes. You have a mark on the lens that points to what you are focusing. For example, if you focus at something 5 meters away it should point at 5 meters. Around this mark are other marks that likely are noted as 16 11 8. What this means is that everything between the marks will be in focus ergo more is in focus at f16 than at f11 than at f8 etc.

 

When you have an image it is generally better to have things in focus from the subject to the camera than behind the subject. Unless you are trying to make a serious point about one subject in a sceen it is usually better to have thew foreground in focus as out of focus subjects in the foreground are often distracting.

 

Ok, next step. Lets say you have focused at that 5 meters and your camera marks for a given f-stop indicate that everything from 8 meters to 2 meters is in focus. What you do is *without even looking through the camera* reposition the focusing mark at 2 meters. Your subject at 5 meters will still be in focus, but now the nearground is in focus and the background will be out of focus.

[lachaine]

I used a K1000 for something like 25 years. As I aged over those years, especially after reaching 40, like many people, my once perfect eyesight deteriorated a bit, and I finally needed bifocal eyeglasses. The K1000 does not have any adjustment for diopter correction, nor does it have a split-image viewfinder to aid in getting accurate focus. I just eventually gave up and moved to a modern autofocus SLR, since I just couldn't focus it accurately anymore. From your description though, I'm not sure if that's the problem you're having. It sounds more like you don't know how depth of field works. The K1000 doesn't have a depth of field preview button, but, unlike most zoom-equipped cameras today, your lens probably has a depth of field scale on it. It's a little hard to explain in a message, but look up depth-of-field in a book - like Kodak's Guide to 35mm photography, for instance. That's your best bet.

[mendel_leisk]

In addition to shallower depth of focus, a wide open lens will invariably be a little softer, even at the critically focussed distance. The more of the lens area used, the more inaccuracies of the lens curvature are evident. I've heard most lens are sharpest somewhere around f8 to f16, and actually soften a little beyond that, say at f22.

 

Also, while a stopped down lens gives deeper depth of focus, and minimises lens curvature inaccuracies, it's obviously a trade-off, if you're hand-holding, due longer exposure times increasing the effect of camera motion.

[minh_thai]

Brandy: Slow down when you shoot! It'll improve the focus sharpness, as well as the composition. Learn to anticipate subject movements, and wait for the right moment. Good luck. M

[brandy_moore1]

Thank you all for your answers. I will try my best. I am currently saving for a new camera so I don't have any other lenses. I had no idea that the aperture had anything to do with focusing. I thought it was just for the amount of light getting to the film. Thanks for my new insight. I'll work with that. Thanks again everyone.

[mendel_leisk]

Here's an example of wider aperture and faster shutter speed, showing shallow depth of focus. Note also the "frozen" looking water:

[mendel_leisk]

(Dang, forgot to caption the above so it would not appear as a link)

 

And the inverse:<div></div>

[mendel_leisk]

Ok here's the one with wide open aperture again and faster shutter speed, with caption:<div></div>