graybeard

I have several chipped "programmable" M42-EOS adapters. I am having difficulty programming them. But perhaps I am confused about exactly what a programmed adapter is supposed to do. I am under the impression that they only function to provide enhanced EXIF data. Such as, if my lens with the adapter is a F3.5 28-80mm I could program it to send the 3.5 and 28mm info to exif. My question is 1. is that correct? and 2. does it serve any other function? I know it does not provide any auto focus or exposure info, I just wondered (aside from not seeming to program it according to the instructions) if I am correct in what the programmed chips are supposed to do. Thanks.

dpullum Loc: Tampa Florida

For my Sony Alpha, the adapter simply fools the camera into thinking it has a lens. Then you add the M-42 and operate manually. M-42 lenses were back in the day when the computer in your camera would have filled room, and been powered by "radio" tubes. Enjoy the mm and low price of the M-42 lenses you have, my 1972 200mm still works, and is HEAVY !!

Does my Sony experience apply to your Canon EOS, perhaps, perhaps not.

Morning Star Loc: West coast, North of the 49th N.

I know nothing about these adapters or EOS, but maybe this will help:
http://www.rugift.com/photocameras/emf-m42-canon-af-adapter-programmable.htm
http://www.peleng8.com/af-lens-adapters/af-m42-canon-silver-m42-canon-eos-lens-adapter.html

CHG_CANON Loc: the Windy City

I don't have one of these, but I have a non chipped adapter for a Sony body and have some experience with adapters, manual focusing and metering, and editing the resulting EXIF data from this configuration.

Reading the "programming" instructions from an item on Amazon and the OP's expectations, it seems the OP is concerned about the EXIF data where the purpose of the tool is photography.

How to Use
Programming setting:
1. Set the maximum aperture on lens.
2. Set the desired aperture on camera.
3. Focus and meter the object, when focus is achieved.
4. Set the lens aperture to the same desired aperture as the camera setting.
5. Press shutter button and take the picture.

The "purpose" of the chipped adapter is to enable the adapter to "talk" to the EOS body for the lens on behalf of the lens that cannot communicate to the EOS body. The camera cannot drive the manual focus or electronic autofocus for a non EOS lens. The EOS body won't meter without a lens, or in the case of a chipped adapter, thinking it has an EF / EF-S mounted. The chip lets the camera body "think" it has an EF / EF-S lens mounted. An ancillary benefit is aperture data is recorded into the EXIF data, but whether the data occurs in the image or not, the purpose of the adapter is to allow metering (and some models, focus confirmation) using an EOS body and non-Canon EF / EF-S lens.

By way of background, when a lens is mounted to a camera with electronic and / or automatic aperture control, the lens is opened to the maximum aperture until the image is captured. The camera closes the aperture on the lens to the desired aperture value only at the instant the shutter is opened and the image captured. The 5-step process above involves the human camera operator performing the same steps on behalf of the camera body. This is work, way more work than using a modern body with a modern lens.

graybeard

I think you have misunderstood me. I have used adapters with and without chips, programmable or not, with and without flanges too. Dumb, smart, and semi-smart. What I want to know is this: when the chips are properly programmed, will the camera, when in manual mode, think it has a lens with the same aperture and MM for the purpose of exif data, and for no other purpose? I would like to be able to look at the info of an exposure and from the aperture displayed to know what lens I had on for that exposure. That is pretty much my whole purpose for fooling around with the tedious and pedantic procedure of programming the adapter. Can you give me any specific info on this ?? Thanks

CHG_CANON Loc: the Windy City

How does your programming process follow or differ from the 5-steps above? In your "programming" process, do you have an additional step to indicate the focal length? Does the focal length appear in the EXIF from the camera? If you are specifying the focal length or typing out a lens name, than it would see it's for EXIF purposes.

Peterff Loc: O'er The Hills and Far Away, in Themyscira.

I think it depends in part on the specific chip, and the programming methods can be straight forward, or sometimes complex to understand from the documentation provided.
My experience is primarily with prime lenses on EOS cameras, using converted FL/FD/FDn lenses, also Contax, Helios, and Nikkor. To this end, I use different adapters for each lens so that the programming only needs to be performed once. I also sometimes use EXIF tool to modify other data fields from preconfigured templates to explicitly state the exact lens specifications.

Although the EXIF data (Focal length and max aperture, etc.) is useful, by far the most useful is focus confirmation in the viewfinder.

blackest Loc: Ireland

I pretty much agree it's focus confirmation that is useful, maybe the focal length, the aperture is fairly useless.

You really need to shoot these in aperture priority mode and at the max aperture. Say f2.8 the camera will meter for the light it sees at f2.8, and work a shutter speed and iso to suit.

If you dial down to say f5.6 it is expecting 2 stops less light so it say makes the shutter speed 2 stops slower. But since it can't stop down you get an image over exposed by 2 stops.

far simpler to focus stop down and take the photo.

just let the camera think the day just got a couple of stops darker.

graybeard

My way of getting exposures with manual lenses is 1. set to M 2. set CAMERA aperture to 1.4 3. set shutter speed to desired speed. 4. adjust LENS aperture ring to meter 5. Focus manually 6. Shoot. I have found that the cameras aperture setting is a trouble maker to a good exposure, so I just set it lower than my lowest ring setting, and it works fine.

Peterff Loc: O'er The Hills and Far Away, in Themyscira.

I mostly agree, but I seldom use the widest aperture, sometimes not even for focusing if I wish to check the depth of field. All of my lenses can be stopped down manually and most are sharper when stopped down a little. Either Aperture priority or simple manual exposure work pretty well for me, although most of the lenses that I use are in the f/1.2 to f/2.0 range. Fully open is useful in low light conditions, but then I would probably use an auto focus lens anyway.

blackest Loc: Ireland

Telling the camera you are using the widest aperture ensures it gets the exposure right for the light it "sees" On some preset lenses i just stop down till the shutter speed stops making sense.

Peterff Loc: O'er The Hills and Far Away, in Themyscira.

I agree. It's a judgement call. It also depends upon whether one is using spot metering and so on. In situations like this we are taking control of the camera aren't we, and choosing a method that works for each of us? Do we always want the 'technically correct' exposure for the entire frame or just the main point(s) of interest?

CHG_CANON Loc: the Windy City

My experience is only with a non-chipped Metabones adapter and manual focus Canon FD lenses, with manual aperture control on the lens, and a Sony A7II. You can tell the camera to operate even when it cannot detect a mounted lens. I don't have to tell the camera the aperture nor do I even have to focus wide open. If I'm having a problem in low light for the desired aperture, I can adjust the ISO or shutterspeed on the camera to gather more light to focus via the EVF. I can then adjust the exposure back and capture the image. With the aperture control on the lens, I usually set the aperture first and work out the remaining exposure parameters on the camera against the histogram and a few test images looking at the highlight warnings.

It would seem that if one is adapting lenses to a digital platform where the aperture can only be used wide open, the wrong lens or the wrong adapter are being used. The process described with the Sony and the manual aperture on the lens is hard enough. Being limited to wide-open shooting would be of no interest for my shooting style, even with experimental work with the Sony and FDs.

blackest Loc: Ireland

you don't shoot wide open you just tell the camera you are shooting wide open. in order for it not to calculate the wrong exposure when you take the shot in aperture priority mode.

In full manual mode you can set as you see fit.

Peterff Loc: O'er The Hills and Far Away, in Themyscira.

Aren't you mixing up or conflating focus with metering? If using back-button focus and separating those functions it doesn't seem to be an issue. Even using half press the functions can be separated, although that is two different steps in the procedure. With a manual focus lens the focus setting isn't going to change on you automatically is it?

So long as you have manual control of the lens aperture setting where is the problem unless you go out of bounds on the metering systems parameters?