Home
SearchSearch MemberlistMemberlist RegisterRegister ProfileProfile Log in to check your private messagesLog in to check your private messages Log inLog in

m4/3 focus confirm question
View previous topic :: View next topic  


PostPosted: Tue Jan 19, 2010 10:44 pm    Post subject: m4/3 focus confirm question Reply with quote

hi

i am seriously considering olypmus m4/3 to use w mf lenses through various adapters. while the adapters i use now, m42/contax/t mount etc, all were advertised as giving 'focus confirmation' on my 5d, i dont see any adapters for m4/3 advertised that way. does anyone know if these same type adapters will allow the focus confirmation of the olly m4/3 cameras to work?

thanks


PostPosted: Tue Jan 19, 2010 10:52 pm    Post subject: Reply with quote

Didnt found this type of adapters. All adapters to m4/3 are without any confirm chip.

Wink


PostPosted: Tue Jan 19, 2010 10:57 pm    Post subject: Reply with quote

thanks rolf. as i understand it, when you manual focus using the lcd screen w these cameras the screen magnifies like 10x. i assume that function still works? but when you achieve proper focus, the green light does not come on, correct?


PostPosted: Tue Jan 19, 2010 11:04 pm    Post subject: Reply with quote

thats right. I dont know how it is with the Oly.

For example if you use a Pentax it is not neccessary to use a confirm chip because the cam find the focus alone. But Pentax is not m4/3. May be that the Oly has the same option - I dont know.

Pansonic dont have this feature. You have to use the magnifier (5x,10x) to find the proper focus.
Wink


PostPosted: Tue Jan 19, 2010 11:10 pm    Post subject: Reply with quote

Rolf wrote:
thats right. I dont know how it is with the Oly.

For example if you use a Pentax it is not neccessary to use a confirm chip because the cam find the focus alone. But Pentax is not m4/3. May be that the Oly has the same option - I dont know.

Pansonic dont have this feature. You have to use the magnifier (5x,10x) to find the proper focus.
Wink


same on the pen (7x, 10x) and you decide if the focus is correct or not.


PostPosted: Tue Jan 19, 2010 11:33 pm    Post subject: Reply with quote

ok, thank you both


PostPosted: Thu Feb 04, 2010 4:46 pm    Post subject: AF Confirm can't work on mirrorless cameras. Reply with quote

There is no way for AF confirm to work on a m4/3 (or Samsung NX) camera, as there is no mirror.

AF confirm is a feature of phase detect (also called "Secondary Image Registration") systems, and require a beam splitter to send some portion of the image through what is basically a tiny rangefinder. You get the AF-confirm indication when when this system detects that you're in focus. Phase-detect AF can actually tell exactly how out-of-focus you are, and thus can snap directly into focus.

Contrast-detect AF, like in the m4/3 cameras, compacts, and video cameras, requires a closed-loop system with the lens, and will always 'hunt' around focus, though good systems hunt only slightly. Just like the eye/photographer system we use for manual focus, you tweak around 'in-focus' looking for the best spot. Again, good photographers hunt only slightly. Smile

Thus, you'll never see AF-confirm adapters for m4/3, as there's no point.


PostPosted: Thu Feb 04, 2010 6:33 pm    Post subject: Reply with quote

thank you n6mod for your thorough explanation.


PostPosted: Fri Feb 05, 2010 10:52 am    Post subject: Re: AF Confirm can't work on mirrorless cameras. Reply with quote

n6mod wrote:
There is no way for AF confirm to work on a m4/3 (or Samsung NX) camera, as there is no mirror.

AF confirm is a feature of phase detect (also called "Secondary Image Registration") systems, and require a beam splitter to send some portion of the image through what is basically a tiny rangefinder. You get the AF-confirm indication when when this system detects that you're in focus. Phase-detect AF can actually tell exactly how out-of-focus you are, and thus can snap directly into focus....


On Panasonic m4/3 cameras there is a green light (top right of the evf), that come on when the correct focus is achieved.
However, this focus confirm feature works only with dedicated lenses, either in Af or MF mode, but not with the adapted ones.


PostPosted: Fri Feb 05, 2010 1:56 pm    Post subject: Reply with quote

yes, i believe that would dedicated lenses would fall under the 'closed system' that was referred to above.


PostPosted: Sat Feb 06, 2010 7:39 pm    Post subject: Re: AF Confirm can't work on mirrorless cameras. Reply with quote

gaman wrote:

However, this focus confirm feature works only with dedicated lenses, either in Af or MF mode, but not with the adapted ones.


In MF mode? That's really interesting. I wonder if the camera is hunting around slightly as you turn the focus ring. (Haven't played with one in MF mode)

-Z


PostPosted: Sun Feb 07, 2010 6:11 pm    Post subject: Re: m4/3 focus confirm question Reply with quote

rbelyell wrote:
hi

i am seriously considering olypmus m4/3 to use w mf lenses through various adapters. while the adapters i use now, m42/contax/t mount etc, all were advertised as giving 'focus confirmation' on my 5d, i dont see any adapters for m4/3 advertised that way. does anyone know if these same type adapters will allow the focus confirmation of the olly m4/3 cameras to work?

thanks


Simple don't need any, 10x magnification more than enough I never miss any focusing aid what is need on SLR cameras.


PostPosted: Sun Feb 07, 2010 7:05 pm    Post subject: Reply with quote

thank you attila, i am sure you are correct. i will be getting the ep1 next week!


PostPosted: Tue Feb 10, 2015 10:07 am    Post subject: M42 on micro 4/3 AF confirm Reply with quote

Hello, I know that due to the contrast detection based focusing system of micro 4/3 cameras, there is no adapter for AF confirm. But what about combining some adapter AF confirm 4/3 to micro 4/3 adapter with an AF confirm adapter m42 to 4/3 (I found some on ebay)? Could this work, does anybody have an experience with this kind of solution? Thank you.


PostPosted: Sun Feb 22, 2015 9:53 pm    Post subject: Re: M42 on micro 4/3 AF confirm Reply with quote

gorg wrote:
Hello, I know that due to the contrast detection based focusing system of micro 4/3 cameras, there is no adapter for AF confirm. But what about combining some adapter AF confirm 4/3 to micro 4/3 adapter with an AF confirm adapter m42 to 4/3 (I found some on ebay)? Could this work, does anybody have an experience with this kind of solution? Thank you.


I have tried this and it doesn't work. I tried using an OM to 4/3 adapter with Tago Tech AF confirm chip attached to the MMF-1 4/3 to m4/3 adapter with electronic contacts on my OMD EM5. The result was the camera kept locking up.

Actually, Tago Tech do (or did) make a dedicated m4/3 AF confirm chip. It is still listed on their store but is showing out of stock.

Click link for Tago Tech Store


PostPosted: Sun Apr 05, 2015 3:06 pm    Post subject: Reply with quote

Some of the newer M4/3 cameras also have focus peaking which can be used by itself or in combination with magnification for manual focusing.

--Geoff