Home

Please support mflenses.com if you need any graphic related work order it from us, click on above banner to order!
SearchSearch MemberlistMemberlist RegisterRegister ProfileProfile Log in to check your private messagesLog in to check your private messages Log inLog in

MF Lense Usage (Especially M42)
Post new topic   Reply to topic
Home   Manual Focus Lenses
View previous topic :: View next topic  


PostPosted: Sun Nov 08, 2009 9:59 am    Post subject: MF Lense Usage (Especially M42) Reply with quote
I received my M42 adaptor with AF confirm chip and counting days to receive my first MF lense now (helios 44-3). As I do not want to harm my EOS450D I need answers to below questions :

1) Is there any risk of harming the cam?
2) How to use the AF Confirm?
3) In which mode will I take pictures? AV-TV-Manuel ?
4) Is there anything else that I need to know?

Thanks a lot ...


PostPosted: Sun Nov 08, 2009 10:34 am    Post subject: Reply with quote
1) some chip sellers want the camera turned off when installing adapter
2) turn aperture to 2, press shutter release slightly, focus - the lights should work when it is right - and then close aperture to right value.
Here is something about aperture preset:
http://forum.mflenses.com/helios-44-3-t5832.html
3) Av and M work, see next answer
4) exposure metering is slightly different
Here is some discussion about these things.
http://forum.mflenses.com/potential-issues-using-mf-on-dslr-t20172,highlight,issues.html


PostPosted: Sun Nov 08, 2009 1:00 pm    Post subject: Reply with quote
1) Ok noted i will turn off first..

2) So it works same as manuel focusing in AF canon lenses (for ex. kit lens 18-55 IS) but turning aperture to 2, why? Will not work at 8 for ex?

As I checked, in the pictures of the Helios the aperture can be set on the lens itself. So what will happen lets say I set the aperture to 2 at the lens and set the aperture to 8 on the camera manuel mode or AV mode???

3) So it is not possible to shoot at TV mode. I have to stick to the values it gives me on AV mode or better use Manuel mode i guess?

4) I will check more about this when I get the lens and do some tests.


PostPosted: Sun Nov 08, 2009 1:10 pm    Post subject: Reply with quote
Hi and welcome Smile

Your camera has no way of setting the aperture on the lens...the lens is fully manual with no electronics. You will ALWAYS need to set the aperture on the lens manually with a Canon DSLR. This is why TV mode doesn't work...the camera can suss out and set the shutter speed, but it cannot stop the aperture down.

The focus confirm may not work at f8 and above as there is not enought light for the camera to see clearly and focus. You will need to focus at f2 and then manually stop the lens down to f8 when ready to shoot.

Hope this helps!


PostPosted: Sun Nov 08, 2009 1:29 pm    Post subject: Reply with quote
"The focus confirm may not work at f8 and above as there is not enought light for the camera to see clearly and focus. You will need to focus at f2 and then manually stop the lens down to f8 when ready to shoot. "

This is very clear thanks.

"Your camera has no way of setting the aperture on the lens...the lens is fully manual with no electronics. You will ALWAYS need to set the aperture on the lens manually with a Canon DSLR. This is why TV mode doesn't work...the camera can suss out and set the shutter speed, but it cannot stop the aperture down. "

There is some confusion for me here. I understand that the aperture will be set on the lens and not the camera but why does not the TV mode work than? I set the shutter speed on this mode no? If i take picture at AV mode, whatever I set at the cam will not matter as the real aperture will be the one on the lens?


PostPosted: Sun Nov 08, 2009 1:53 pm    Post subject: Reply with quote
Tharos wrote:

There is some confusion for me here. I understand that the aperture will be set on the lens and not the camera but why does not the TV mode work than? I set the shutter speed on this mode no? If i take picture at AV mode, whatever I set at the cam will not matter as the real aperture will be the one on the lens?


Yes the camera works also on Tv mode but then the exposure metering is useless. If it is in M mode then the meter tells if exposure is under or over. And Av mode camera does change the shutter speed.


PostPosted: Mon Nov 09, 2009 8:33 am    Post subject: Reply with quote
Guess it will be more clear to me when I receive and test the lens...

How about the A/M switches on the lense? What is the difference in auto and manuel mode of the lense?


PostPosted: Mon Nov 09, 2009 8:43 am    Post subject: Reply with quote
Tharos wrote:
Guess it will be more clear to me when I receive and test the lens...

How about the A/M switches on the lense? What is the difference in auto and manuel mode of the lense?


When the A/M swithch is in M mode then the aperture changes when you turn the aperture selection ring. In A mode the aperture changes when the actuator pin is pressed.


PostPosted: Mon Nov 09, 2009 9:04 am    Post subject: Reply with quote
Tharos wrote:
I understand that the aperture will be set on the lens and not the camera but why does not the TV mode work than? I set the shutter speed on this mode no? If i take picture at AV mode, whatever I set at the cam will not matter as the real aperture will be the one on the lens?


As mentioned above, you “can” use the camera in the Tv mode (assuming that's Canon-talk for shutter priority). However, it doesn't work as intended—the aperture control in the camera has no effect, because the camera has no way to control the aperture on an M42 lens. So if you set a given shutter speed in Tv mode, say 1/125s, and the camera figures that “okay, the correct exposure would be at aperture f/8”, the lens itself never receives the command to stop down to f/8 because it doesn't communicate with the camera. So Tv mode ends up being the same as M, except that the camera tries in vain to control the aperture (which it can't).

Likewise in M and Av modes you can only control the aperture by turning the ring on the lens itself. The in-camera aperture setting only serves to fool the camera; if it's available with a chipped adapter, it must be set to the widest available setting, regardless of whether or not it matches the lens or your shooting aperture. For example, if you can select f/1.4 as the widest in-camera setting, your lens is f/2 and you are shooting at f/8, you need to set f/1.4 in the camera… Otherwise you are telling the camera that “what you are seeing now is at f/1.4 (or whatever the widest available setting is), and when I take the picture you should stop down the lens and compensate metering accordingly”.


PostPosted: Tue Nov 10, 2009 10:04 am    Post subject: Reply with quote
"When the A/M swithch is in M mode then the aperture changes when you turn the aperture selection ring. In A mode the aperture changes when the actuator pin is pressed."

So which is better and why would you choose one mode over another?


Arkku : As far as I understood it is best to shoot in M mode as it is possible to set to F1.4 (to fool the cam) and also control the shutter speeds according to the situation by yourself at the same time. In AV mode when you set F1.4 for example you would not get the best shutter value from the camera, would you?

Let's say I want to shoot at F8, why would not I choose F8 in AV mode but instead I should choose F1.4 and fix exposure later?


PostPosted: Tue Nov 10, 2009 11:10 am    Post subject: Reply with quote
Tharos wrote:
"When the A/M swithch is in M mode then the aperture changes when you turn the aperture selection ring. In A mode the aperture changes when the actuator pin is pressed."

So which is better and why would you choose one mode over another?


In A-mode (of the lens) you can only shoot wide open because the camera can't control the aperture of M42 lenses. So you must use M mode. (Or you need an adapter which presses aperture actuator pin, but then A and M modes are the same, no difference at all.)


Tharos wrote:

Let's say I want to shoot at F8, why would not I choose F8 in AV mode but instead I should choose F1.4 and fix exposure later?


Let's say the maximum aperture you can choose with your adapter is f/1.4. Let's also say that the maximum aperture of your lens is f/2 (e.g. Helios-44) and you wish to shoot at f/8:

1) You select f/8 on the camera.
2) You stop down the lens to f/8 (because in-camera setting cannot control the lens).
3) The camera assumes that it is now looking through an f/1.4 lens wide open and that the aperture will be stopped down to f/8 when the picture is taken. The camera takes this amount of light (which it believes to be at f/1.4) and adjusts shutter speed for 4 stops less light to make exposure right for f/8.
4) You take the picture. The camera attempts to stop down the lens to f/8, but can't because it can't control an M42 lenses. The photo is overexposed by 4 stops.

So you must set the camera to the widest aperture setting in any mode, no matter the lens and shooting aperture! Then it goes like this:

1) You select f/1.4 (or whatever the widest setting is) on the camera.
2) You stop down the lens to f/8.
3) The camera assumes that it is now looking through an f/1.4 lens wide open, and this is the setting at which it will remain when shooting. The camera sets exposure according to this amount of light.
4) You take the picture. The camera does not attempt to stop down the lens because you are at the widest aperture setting. The photo is exposed correctly (assuming correct metering =).


PostPosted: Wed Nov 11, 2009 12:31 pm    Post subject: Reply with quote
I received my lense last night (Helios 44-3) and tried to figure our a few things.

Arkku: Your explanation is pretty clear thanks. As I could not use AF confirm chip (I will explain that later in the message), I could not change aperture, it was F00. Or if there is something else that can be done (from the camera menu) please let me know. But I shoot at Manual mode and do like this :

I set the lens aperture, I set the shutter speed in manual mode and than I check the exp. meter and arrange the values accordingly. Maybe not the fastest method but it does the trick for me.

I had a problem with the adaptor and the lense. First of all, I connected the adaptor and the lens and than plugged this to the cam. As the lense is tight on the cam the focus wheel do not turn and when I manage to turn it, the complete lense starts to turn, not just the focusing wheel. So it is difficult to focus for me. A friend of me said it can be fixed but I want to hear your experiences first.

After taking out the adaptor the AF confirm chip dropped. Is it because it is cheaply made? (I paid approx. 30USD for this chip). I am thinking of contacting the seller at bay, what do you suggest?


PostPosted: Wed Nov 11, 2009 1:43 pm    Post subject: Reply with quote
Tharos wrote:
IAs I could not use AF confirm chip (I will explain that later in the message), I could not change aperture, it was F00. Or if there is something else that can be done (from the camera menu) please let me know.


As stated above, you must not try to set the aperture in camera. Without a chip in the adapter, you can't set it, so this is the correct way to use it.


PostPosted: Wed Nov 11, 2009 2:15 pm    Post subject: Reply with quote
What would you suggest about the easily dropping of the AF confirm chip? I am thinking of contacting the seller.

Or is it a common problem?


PostPosted: Wed Nov 11, 2009 2:59 pm    Post subject: Reply with quote
Tharos,
I would certainly contact the seller. You might get a partial refund, a replacement or at least instructions for repairing it. I have several adapters, and until now, they all worked fine.

If you know the exact location of the AF-chip (or you could ask the seller to a technical drawing with this precise location), you can fix it by glueing it in again. I didn't have to try this yet, but I guess others on this forum could have more experience in this.

I started the same way you did: M-mode, changing aperture on the lens and then look in the viewfinder to set time, according to the measured exposure. After a while, I noticed that I forgot to set the time value.

Now, I am using Av-mode: it sets the time automatically now. It's much more convenient and easier.


PostPosted: Wed Nov 11, 2009 3:18 pm    Post subject: Reply with quote
youngcoby: I believe AV mode should be ok if your using a non-AF confirm chip but what happens when you use AF confirm chip?

As Arkku mentioned earlier Canon's measure light at full open and than calculates the desired values according to F8 for example accordingly and change the lens aperture to F8 when your taking the picture but as it will not be able to control the MF lense aperture than you might have overexposed pictures. I believe that would be harder to handle. But maybe I am wrong Smile

I am looking forward for the weekend to go out and try the new lense ... Hope it wont rain Smile


PostPosted: Wed Nov 11, 2009 4:48 pm    Post subject: Reply with quote
Tharos wrote:
What would you suggest about the easily dropping of the AF confirm chip? I am thinking of contacting the seller.


You could try to glue the chip yourself. One way to align the contacts is to put the adapter on the camera with no lens attached, see where the contacts land and mark the position for the chip. Of course if you feel uncomfortable doing this, you should contact the seller for a new one, but unless they are willing to just send you another one I think the return shipping of the one you already have costs too much to be worthwhile.


PostPosted: Wed Nov 11, 2009 5:39 pm    Post subject: Reply with quote
Reading this thread in order to know what's about "false" light reading with m42's & DSlr's... well i wondered if some of you have used a light meter to check correct camera metering ?


PostPosted: Wed Nov 11, 2009 5:42 pm    Post subject: Reply with quote
Maybe we should have an FAQ on this as it comes up a lot.


PostPosted: Wed Nov 11, 2009 6:14 pm    Post subject: Reply with quote
Tharos wrote:
youngcoby: I believe AV mode should be ok if your using a non-AF confirm chip but what happens when you use AF confirm chip?

As Arkku mentioned earlier Canon's measure light at full open and than calculates the desired values according to F8 for example accordingly and change the lens aperture to F8 when your taking the picture but as it will not be able to control the MF lense aperture than you might have overexposed pictures. I believe that would be harder to handle. But maybe I am wrong Smile

I am looking forward for the weekend to go out and try the new lense ... Hope it wont rain Smile


@Tharos:
I use only adapters with AF confirm chips. And in Av mode it changes automatically the time needed to get a good exposure.

I just checked it: 2 pictures, one wide open, one fully closed down. The first picture needed 4 seconds, the latter 30 seconds. No other changes were made, except the manual closing down of the lens.


PostPosted: Wed Nov 11, 2009 6:36 pm    Post subject: Reply with quote
hexi wrote:
Reading this thread in order to know what's about "false" light reading with m42's & DSlr's... well i wondered if some of you have used a light meter to check correct camera metering ?


when over 50% picture is clipped black or white in just normal light and/or looks andy warhole?


PostPosted: Wed Nov 11, 2009 6:54 pm    Post subject: Reply with quote
I don't understand ....

What i wonder is if checking by an external lightmeter is as/more accurate as the dslr metering ?


PostPosted: Wed Nov 11, 2009 10:07 pm    Post subject: Reply with quote
youngcoby : Your test is ok but I mean something else, maybe it is better if you read earlier messages from Arkku in this post.

My english is not so great but I try to explain :

Let's say you want to have F8 and arrange the lens manually accordingly.
In AV mode if you set F8, until you shoot the aperture is at lowest in AF lenses so the cam receives the light at maximum aperture (lets say F1.4) and than a CPU calculates the light for F8 which you desire and when you take the picture the aperture closes to F8 and there you go. Theres maths going on inside the cam.

So I am not so clear how the camera decided correctly on the shutter speed in AV mode, as the calculation will not be accurate (as the cam can not control the lense)...

If you set the aperture on the AV mode as F1.4 than it is more correct but still I am not sure if it is perfect though.

Maybe I am skipping something here, correct me if I am wrong, I am newbie myself Smile


PostPosted: Wed Nov 11, 2009 10:58 pm    Post subject: Reply with quote
Tharos wrote:
youngcoby : Your test is ok but I mean something else, maybe it is better if you read earlier messages from Arkku in this post.

My english is not so great but I try to explain :

Let's say you want to have F8 and arrange the lens manually accordingly.
In AV mode if you set F8, until you shoot the aperture is at lowest in AF lenses so the cam receives the light at maximum aperture (lets say F1.4) and than a CPU calculates the light for F8 which you desire and when you take the picture the aperture closes to F8 and there you go. Theres maths going on inside the cam.

So I am not so clear how the camera decided correctly on the shutter speed in AV mode, as the calculation will not be accurate (as the cam can not control the lense)...

If you set the aperture on the AV mode as F1.4 than it is more correct but still I am not sure if it is perfect though.

Maybe I am skipping something here, correct me if I am wrong, I am newbie myself Smile


Well the sunny 16 rule works quite well, and also there is a direct relationship between shutter speed, f stop and asa/iso, so it's not complicated for a camera, when designers/engineers know this.
Problems could arise for very accurate exposure when the lens doesn't actually stop down exactly to what is selected.


PostPosted: Thu Nov 12, 2009 7:11 am    Post subject: Reply with quote
Tharos wrote:
when you take the picture the aperture closes to F8 and there you go. Theres maths going on inside the cam.


I think you're complicating it Smile I do this:

1. Switch to AV mode but don't set aperture on the camera
2. Focus wide open (it's easier)
3. Stop the LENS down to f8 manually
4. Take the picture

Various DSLRs behave differently when taking this simple approach e.g. Sonys tend to under expose with each lens stop down. I use exposure compensation to sort this. But you have an LCD screen to see the photo afterwards, so checking and changing settings is no problem. My EOS 30D tends to overexpose as you stop down, so I compensate the other way around.

It's a bit of a fiddle but you soon get to understand when the camera will be fooled, and you can adjust accordingly Smile
Post new topic   Reply to topic
Home   Manual Focus Lenses
Goto page 1, 2  Next
Page 1 of 2