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07-30-2012, 09:06 AM   #1
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difference between "focus indicator" with "matte field"

In manual P132-133, it shows two ways to use MF focus mode. In ur opinion, which way is easier to use? For me, I like to hear a beep before I press the shutter release button fully.

is there any benefit to use matte field?

07-30-2012, 09:54 AM   #2
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Focussing with the matte screen of an APS-C body is generally difficult and needs a lot of practice, good eyes, a fast lens, and generally lots of light. With wide-angle optics it is often impossible, as the range in which the picture seems to be sharp (in the viewfinder!) is just too big.

But also the beep does not guarantee you nailed focus exactly. Like with the matte screen, there is always a range where the green hexagon shows, an the beep sounds at its first appearance. Often the middle of the range is the best, but there may be copy variation and you have to experiment with your camera and practice. Be aware that - with super wide lenses - this range can be quite big.

The precision of what you can achieve with both techniques depends on different things. The matte screen must be positioned at exactly the same distance to the object as the sensor. This can only be corrected by changing a shim which fixes the screen in that position.
The green hexagon uses the auto focus sensors and electronic, and its precision depends on dozens of mostly adjustable mechanical parameters which (hopefully) were set when the body was assembled. Errors of some (not all!) of these can be overridden mathematically when you set AF focus correction.

Generally, today's APS-C auto focus cameras are not well prepared to use the matte screen. In manual focus times, the manufacturers put great efforts to get the best possible viewfinder to help you. Since AF took over, they made some big steps backwards.
07-30-2012, 07:06 PM   #3
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QuoteOriginally posted by RKKS08 Quote
Focussing with the matte screen of an APS-C body is generally difficult and needs a lot of practice, good eyes, a fast lens, and generally lots of light. With wide-angle optics it is often impossible, as the range in which the picture seems to be sharp (in the viewfinder!) is just too big.

But also the beep does not guarantee you nailed focus exactly. Like with the matte screen, there is always a range where the green hexagon shows, an the beep sounds at its first appearance. Often the middle of the range is the best, but there may be copy variation and you have to experiment with your camera and practice. Be aware that - with super wide lenses - this range can be quite big.

The precision of what you can achieve with both techniques depends on different things. The matte screen must be positioned at exactly the same distance to the object as the sensor. This can only be corrected by changing a shim which fixes the screen in that position.
The green hexagon uses the auto focus sensors and electronic, and its precision depends on dozens of mostly adjustable mechanical parameters which (hopefully) were set when the body was assembled. Errors of some (not all!) of these can be overridden mathematically when you set AF focus correction.

Generally, today's APS-C auto focus cameras are not well prepared to use the matte screen. In manual focus times, the manufacturers put great efforts to get the best possible viewfinder to help you. Since AF took over, they made some big steps backwards.
Thanks. I will stick with Focus indicator method for now if I need to use MF. As an new Dslr user, I found it is not easy to do manual focus.
Also, in manual, it says I need to turn the focus ring( not zoom ring). So I think it is the smaller ring on the lens. That is what I practiced this morning as well. If you could confirm my guess, that would be great. Pls see the attached.
Attached Images
 
07-31-2012, 02:12 PM   #4
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I own only one DA zoom lens, the 18-55 WR, and with this the focus ring is at the front of the lens. But with AF lenses it is usually the smaller ring.

If, some time in the future, you are working often with very fast manual prime lenses (extremely small DOF), you may find focussing becomes really difficult no matter which method you will use.

In this situation the best solution would be to change the matte screen against a focus screen with some built-in optical focus help. Specialized focussing screens can provide a big advantage. I did not mention this in my first post as I understood you are a beginner, and to circumnavigate the also existing disadvantages of such a screen, you will need some experience and knowledge of your camera. But you can do a search in this forum any time - there are multiple threads about this subject. Just look for "focussing screen".

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