T Nation

How to Focus a Camera?


#1

Is it possible to focus a camera, using 70 mm, so that both up close and far away objects are clear and easy to see?


#2

Read the manual.


#3

I cant see the reply by iron dwarf so apologies if i repeat. If you have an SLR set the aperture to something like F16/F22+ , youll need a nice bright day as the shutter speed could get alittle slow to hand hold.

The aprox. rule is the shutter speed should be at least the reciprical of your lens so you should be looking at at least 1/70th of second which would be around 1/90th on an SlR although some are more exact these days than the old style. If this is a problem use a faster film, Im old school but from playing with digital SLRs i believe you can change the ISO ratings to suit.


#4

[quote]kickingking wrote:
I cant see the reply by iron dwarf so apologies if i repeat. If you have an SLR set the aperture to something like F16/F22+ , youll need a nice bright day as the shutter speed could get alittle slow to hand hold.

The aprox. rule is the shutter speed should be at least the reciprical of your lens so you should be looking at at least 1/70th of second which would be around 1/90th on an SlR although some are more exact these days than the old style. If this is a problem use a faster film, Im old school but from playing with digital SLRs i believe you can change the ISO ratings to suit.

[/quote]

Thanks for the excellent reply. What I’d like to get are clear shots fairly close, and the mountains behind still clear as well.


#5

Use a wider lens and set the aperture fairly high.


#6

The best you can do is stop the aperture down as i said, most lenses will go to F22(higher the number - smaller the aperture - greater the depth of field), some will go higher, depending on how close the first object is i would say either focus on that object or perhaps alittle passed it and you should be getting a really good depth of field with everything in focus. Remember to check your shutter speed isn’t too low and all should be good.

If you have a depth of field preview button, or stop down button as it used to be called on some old SLRs you can see how the image will turn out. Obviously if its digital you can cheat and look at the image prior to printing.