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Manual focus lenses on AF body (Mamiya 645 AFD)

Shineofleo

New member
I think this is a rookie question and I guess I got the answer but to confirm.

I have old manual focus lense in Mamiya 645 format for example 45mm F/2.8 C, just put on Mamiya AFDIII body. I found that I had to stop down the aperture to get correct metering. This is all right because I planned to use M mode anyway. However...

a) If I stop down to e.g. F11, it is very dark to focus
b) The electronic focus indicator stops working under F11

I guess the M/A switch helps here: I can switch to A to see the brighter viewfinder, focus; then switch to M to stop down to take a photo (If I use Av mode, now I can get the correct exposure with suggested shuttle release number).

So is that the correct way? The shuttle release will not trip the aperture in A mode? As I can see this manual lens doesn't have aperture level like Nikon lens, so I have to do A switch to focus and M switch to take a photo (especial with smaller aperture)...

Also, the F number can not pass to the body so it is '--' all the time.

Any comment is appreciated. Thanks!


Leon
 

Bill Caulfeild-Browne

Well-known member
I think this is a rookie question and I guess I got the answer but to confirm.

I have old manual focus lense in Mamiya 645 format for example 45mm F/2.8 C, just put on Mamiya AFDIII body. I found that I had to stop down the aperture to get correct metering. This is all right because I planned to use M mode anyway. However...

a) If I stop down to e.g. F11, it is very dark to focus
b) The electronic focus indicator stops working under F11

I guess the M/A switch helps here: I can switch to A to see the brighter viewfinder, focus; then switch to M to stop down to take a photo (If I use Av mode, now I can get the correct exposure with suggested shuttle release number).

So is that the correct way? The shuttle release will not trip the aperture in A mode? As I can see this manual lens doesn't have aperture level like Nikon lens, so I have to do A switch to focus and M switch to take a photo (especial with smaller aperture)...

Also, the F number can not pass to the body so it is '--' all the time.

Any comment is appreciated. Thanks!


Leon
I think you have it right. (When I used manual lenses on the AF I used an external (old Weston Master!) meter because the camera meter gives erroneous readings.)
 

Shineofleo

New member
I think you have it right. (When I used manual lenses on the AF I used an external (old Weston Master!) meter because the camera meter gives erroneous readings.)
Thanks! Actually I use light meter as well. The major problem is the dark viewfinder so I can not focus properly. So I have to set the switch to A to focus then stop down.

Hmmm so the manual lens is not the problem of focus, there is metering trivia as well...
 

ondebanks

Member
I think this is a rookie question and I guess I got the answer but to confirm.

I have old manual focus lense in Mamiya 645 format for example 45mm F/2.8 C, just put on Mamiya AFDIII body. I found that I had to stop down the aperture to get correct metering. This is all right because I planned to use M mode anyway. However...

a) If I stop down to e.g. F11, it is very dark to focus
b) The electronic focus indicator stops working under F11

I guess the M/A switch helps here: I can switch to A to see the brighter viewfinder, focus; then switch to M to stop down to take a photo (If I use Av mode, now I can get the correct exposure with suggested shuttle release number).

So is that the correct way? The shuttle release will not trip the aperture in A mode? As I can see this manual lens doesn't have aperture level like Nikon lens, so I have to do A switch to focus and M switch to take a photo (especial with smaller aperture)...

Also, the F number can not pass to the body so it is '--' all the time.

Any comment is appreciated. Thanks!


Leon
Yes, you are correct. Although I did not understand your reference to "doesn't have aperture level like Nikon lens"?

If I want to shoot a manual focus lens at f5.6 or wider, I just set the lens f-stop - the focus confirmation works and the view is bright enough.

At f8 or smaller, what I usually find is faster than fiddling with the A-M switch, is just turning the aperture ring to wide open for focusing, and back again to my desired f-stop for metering/shooting. The aperture rings have click-stops, so I know without looking that e.g. f/11 on an f2.8 lens is 4 clicks to the right.

Ray
 

Shineofleo

New member
Yes, you are correct. Although I did not understand your reference to "doesn't have aperture level like Nikon lens"?

If I want to shoot a manual focus lens at f5.6 or wider, I just set the lens f-stop - the focus confirmation works and the view is bright enough.

At f8 or smaller, what I usually find is faster than fiddling with the A-M switch, is just turning the aperture ring to wide open for focusing, and back again to my desired f-stop for metering/shooting. The aperture rings have click-stops, so I know without looking that e.g. f/11 on an f2.8 lens is 4 clicks to the right.

Ray
Sorry my typo... it is "aperture lever like Nikon lens". The lever can change aperture size which will be coupled with the body. The 645 lenses doesn't have such physical part so I think it is just impossible for the body to change the aperture. MF Mamiya camera however, does has such mechanism to change aperture...

By the way, so for full MF lenses, it can also be adapted to other camera such as Nikon, because there is aperture ring. However with AF lenses, which has no aperture ring, it is impossible to use with other camera is that correct?
 

ondebanks

Member
Sorry my typo... it is "aperture lever like Nikon lens". The lever can change aperture size which will be coupled with the body. The 645 lenses doesn't have such physical part so I think it is just impossible for the body to change the aperture. MF Mamiya camera however, does has such mechanism to change aperture...
Ah, yes I understand the part you mean now. You are correct that the AF Mamiya bodies lack the mechanical couplings to either engage the MF lens' aperture lug for metering or to stop it down at the instant of exposure.

By the way, so for full MF lenses, it can also be adapted to other camera such as Nikon, because there is aperture ring. However with AF lenses, which has no aperture ring, it is impossible to use with other camera is that correct?
It is possible to use the AF lenses on other cameras, with the big restriction that you can only shoot at wide-open aperture. For most people, that's the same as saying "it's impossible", but there are scenarios when I do it.

If you do attempt to do this however, be aware that not all adapters for M645 lens -> smaller format cameras can physically mount the AF lenses. The first adapters I had from Zoerk, for example, cannot, but the Cirrus one I got later can. The reason is that while the bayonet is the same, the diameter of the flat surface at the back of the AF lenses is wider, and some adapters have a slight protruding lip which falls foul of this.

Ray
 

Shineofleo

New member
Ah, yes I understand the part you mean now. You are correct that the AF Mamiya bodies lack the mechanical couplings to either engage the MF lens' aperture lug for metering or to stop it down at the instant of exposure.



It is possible to use the AF lenses on other cameras, with the big restriction that you can only shoot at wide-open aperture. For most people, that's the same as saying "it's impossible", but there are scenarios when I do it.

If you do attempt to do this however, be aware that not all adapters for M645 lens -> smaller format cameras can physically mount the AF lenses. The first adapters I had from Zoerk, for example, cannot, but the Cirrus one I got later can. The reason is that while the bayonet is the same, the diameter of the flat surface at the back of the AF lenses is wider, and some adapters have a slight protruding lip which falls foul of this.

Ray
Ah yes, it is possible to use AF lenses on other cameras but only with max aperture... I think it is more 'fun' than practical to adapter lenses to different format.

Very helpful. Thanks!

I think I will try to hunt 'no aperture ring' version lenses for my AFDIII first...
 
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