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Old Nov 14, 2010, 9:21 PM   #21
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For a Screw mount lens, I set the slider on the lens to the manual setting and then either set the mode button to AV and then set the aperture ring to the setting I wish to shoot at and let the camera set the shutter speed, ORRR set the mode dial to manual mode set the aperture to wide open, Set the shutter speed to the speed I wish to use, Focus..then stop the lens down to the aperture I want to shoot at.

With the first way you get focus confirmation to f/8 or f/11 so it works for most photos and really is the easiest way. I shoot thousands of good photos every year this way.

With your original problem

Go to the custom menu and check the box for Aperture ring use allowed.
If you set your A lens to the A setting then set the Mode to AV and push the shutter halfway. This will set the Shutter speed and when you focus it should give you focus confirmation. Pushing the shutter all the way down should take the photo with your Aperture setting and the camera's shutter speed setting. Thus a good exposure. Change the EV+ or - to darken or lighten the exposure.

Do things one step at a time. Work out this manual lens problem by doing things one step at a time and know that we ALL have had a problem or two getting to where we are right now. Be patient with us and we will be the same with you. There is no problem we cannot solve together. This is the reason you see so many posts here...there are good and knowledgeable folks here that want to help, because others in the past have helped us.
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Old Nov 18, 2010, 10:34 AM   #22
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My apology for being so late in thanking everyone for their responses to my post (#14). I was out of town with no internet access (that sux), but I appreciate your input.
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Old Nov 27, 2010, 10:53 PM   #23
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So just when I thought (emphasis on THOUGHT) I had this manual lens thing licked, it kicks my butt again.
So let me explain what I am doing, and either I am not using it properly, or I do not understand how metering works, not sure which at this point.
1 Assume settings are correct as it does take pictures.
So I set the dial to M (manual).
Set focal length when power on.
Set up shot.
Pres +/- AV button 9which i assume is takeing a meter reading).
Take shot.

As long as the lens is wide open (2.5 in this case) seems to be exposed fine.
If I adjust the F stop for more DOF (say F8) the picture is MUCH darker.
So I adjust F stop, press +/- AV button for a new reading, and then press shutter.
Now I would assume the camera would adjust the shutter speed to give at least close to the proper exposure.
Example, ISO 200, tripod mounted, 2 sec shutter delay (macro photography).
F 2.5, press AV, take shot, looks good, just no DOF.
Change F stop via ring to F 5.6 pres AV button, take shot, very dark.
Change F stop to f8, press AV button, so dark can not see image.

How ever I did find I could spin the thumb wheel and change the shutter speed manually to get a decent exposure on say F8, but the camera does not seem to be doing it.

And yes, I went though all the links here once again to make sure (or so I thought) I understood the procedure.

So what is stupid me either doing wrong, or not understanding.

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Old Nov 28, 2010, 1:51 AM   #24
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I've looked at your opening post, and the results do indeed look puzzling. However, let's try and be methodical here. Exposure problems can be caused by any of 3 things:

1. Procedural problem (on the part of the user). You seem to be doing the right thing, so it shouldn't be this.

2. Metering problem. When I do stop-down metering (i.e. Av button in M-mode) on my K-m, the mirror flips - does your camera do this? And does the camera set appropriate shutter speeds (going from f4 to f8, say, should result in a reduction in shutter speed by a factor of around 4)?

3. Operational problem. Does the camera implement the promised shutter speed? You could check this, I suppose, using very slow shutter speeds. Also, check the EXIF info for correct shutter speeds. I suppose there could be a lens problem, so examine the lens for correct aperture-ring and stop-down lever operation.

I can't think of anything else at the moment, but I'll keep trying (I like a puzzle!).
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Old Nov 28, 2010, 4:06 AM   #25
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Hi fofa,

I've pretty much stayed out of this discussion because I really don't use manual mode or manual lenses that much. . . I figured that many others were a lot more experienced with manual exposure and would be able to come up with the solution. I mostly use a K20 and K-7 and I've used M mode and the green button a bit.

I was playing with my K100DS with my A 70-210/4 with the aperture ring off the "A" position. The first thing -- I was a little surprised that an exposure meter display didn't light up in the VF in M mode, as I know does with the K-7 and such. I then followed your procedures, and was getting the same result.

I knew that this had to be wrong, because the lens didn't stop down to meter when I pressed the button Av(+/-). I got to thinking, and remembered that on the single e-dial bodies in M mode, depressing the Av button and turning the e-dial changes the aperture with an "A" lens, so it really couldn't be used to set the starting exposure as the functions would conflict.

It occurred to me that the AE-L button was actually a more logical button to use for this purpose to set a starting exposure automatically, and there's really no use for a button to lock the exposure settings in M mode since that's what M mode does.

Lo an behold, I tried the AE_L button, and the aperture stopped down, and the shutter speed changed for differing lighting intensities, then also changed when I kept the lighting the same and changed the aperture with the ring. . .

I think we're in for a collective "Doh!" on this thread. . . Sorry I didn't play with this sooner. . .

I am assuming that the K2000 continued on with the same logic to the button functions. . .


Last edited by snostorm; Nov 28, 2010 at 4:34 AM.
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Old Nov 28, 2010, 10:16 AM   #26
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I haven't been read this thread but I have a KM, which is what the K2000 is known as, outside of the USA.

I just have used an A lens...my 35-105mm Pentax Macro lens on my K mount, digital bodies and not a lot.

I set it on 'A' and if I'm using the tripod....it's important to turn off the Shake Reduction feature.

On the KM just scroll through the menu.

I've taken thousands of pictures with my KM....never really had such a poorly exposed shot as the last picture in your trio you display in your original post.

The KM / K2000 is quite a competent little unit.

This may have been mentioned but if the camera only does this with that older lens and works fine with say other lens you have....and you may just have the 18-55 that came with it...might be the old lens.

That lens your using.....I'm not familiar with it.....but I wonder if that's the problem.

I have two very old lenses, that I bought...new.. back in the early 70's....lousy on my M42 (screw mount) bodies, lousy on my K mounts. They were poorly designed and made. Not the same brand as you have....but I'm just saying some old stuff (non-Pentax) from way back when...wasn't good.

I'm no expert, with old non-Pentax lenses...but there are those (Big Dawg for one) well versed on these lenses.
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Old Nov 28, 2010, 3:13 PM   #27
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Originally Posted by fofa View Post
So just when I thought (emphasis on THOUGHT) I had this manual lens thing licked, it kicks my butt again.
So let me explain what I am doing, and either I am not using it properly, or I do not understand how metering works, not sure which at this point.
1 Assume settings are correct as it does take pictures.
So I set the dial to M (manual).
Set focal length when power on.
Set up shot.
Pres +/- AV button 9which i assume is takeing a meter reading).
Take shot.

On a Pentax K2000 using a Pentax SMC M 135 f3.5 lens (not m42 thread mount lens)
Set C menu item 19 Using Aperture ring to (2)
mount manual lens Pentax M
Set dial to M
Focus Get focus conformation
Push AV+/- button (you should hear and see the aperture close down)
Take photo

When ever you move the camera (change lighting) push the AV button again

The only other thing you may have some other option set in the menu diff than I do???


If you are still having problems e mail me your phone number thru the forum e mail and we can talk our way through it

...It is better to burn a roll of film than curse the darkness. Equip. K30, Q7, DAL 55-300, DA 35 f2.4, DA 50 f1.8 DA 18-135, SMC-M 28 f3.5, SMC M 50 f1.4, Canon P&S S100 w/CHDK Beta, Panasonic DMC-GM5, Flickr:

Last edited by hnikesch; Nov 28, 2010 at 3:59 PM.
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Old Nov 28, 2010, 4:02 PM   #28
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I think snostorm has is right- if you are not seeing a change in your VF when you change lens settings, your camera is keeping the aperture wide open. This is OK, but if it doesn't change when you press the button, it won't be able to meter correctly.
It is funny that we have taken so long to get the answer, but I, for one, have found that using Av mode, even with fixed aperture or manual lenses, is much more efficient. And, of course, the *istD is set up a bit differently for this. Live and learn.

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