[Tonytee]

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Okay, here is my situation. I have two Takumar lenses, one is an SMC 135mm f3.5 and the other is a Super-Takumar 50mm f/2.0. Both lenses are in excellent condition. Recently my Asahi Spotmatic F gave up the ghost, so I resorted to using an adapter on my Pentax ME. One of my concerns is if I need to be aware of any issues when using these lenses on the ME, given the fact that the lenses will farther away from the mirror and meter. The other concern is if I need to keep the lenses on Auto or Manual when in use. I assume I would have to keep them on Auto since the ME is on Auto and is an Aperture Priority set up. Thanks very much for any assistance offered.

Regards,

Tony

[sergysergy]

If you use the right adapter you should have no problems using them.

[Tonytee]

If you use the right adapter you should have no problems using them.

Thank you very much. So, what you are saying is that I can use the lenses on either Manual or Auto. Great. Appreciate your info.

Tony

[sergysergy]

I am not sure about the auto/manual part but the distance is the same if I am not mistaken
That's why you can use takumars in modern bodies too.

[promacjoe]

wrong. When focusing, the aperture should be wide open. But before you take the picture, you need to turn the depth of field preview on, on the lens And adjust the aperture the way you want it. Leave the depth of field preview on when taking the picture. auto aperture will not work on any thing but a screw mount camera body.

[Tonytee]

wrong. When focusing, the aperture should be wide open. But before you take the picture, you need to turn the depth of field preview on, on the lens And adjust the aperture the way you want it. Leave the depth of field preview on when taking the picture. auto aperture will not work on any thing but a screw mount camera body.

Thank you for the info. I have one more question. I have the lens mounted on the Pentax ME Camera. I kept the lens wide open while focusing, however, I do not know how to keep the depth of field preview open on this lens. I can see the scale, but how do I keep it open?

Thanks. Tony

[Dartmoor Dave]

One of my concerns is if I need to be aware of any issues when using these lenses on the ME, given the fact that the lenses will farther away from the mirror and meter. The other concern is if I need to keep the lenses on Auto or Manual when in use. I assume I would have to keep them on Auto since the ME is on Auto and is an Aperture Priority set up.

When you say that your "lenses will be farther away from the mirror and meter" does that mean that you're using a flanged adapter like this one? Adapter Ring M42 Lens to PK Pentax for Pentax KM K M K 7 K x K2000 K20D Free | eBay If so, you're going to have problems achieving infinity focus. You need to use an adapter similar to the genuine Pentax adapter, like this: Genuine Pentax Mount Adapter K for M42 Lens to K Mount Japan | eBay

Using the right adapter will keep the lens registration distance correct and avoid problems with infinity focus.

As for the Auto/Manual switch: the Pentax ME has no way of letting you focus wide open with an M42 lens then automatically stopping down when you release the shutter. So if you leave the switch on Auto all your shots will be taken with the lens wide open. The correct procedure is to set the aperture ring on the lens to the f-stop you want to shoot at, then slide the switch to Auto while you focus. This will keep the lens wide open for easier focusing. When you're ready to shoot, slide the switch to Manual and the lens will stop down to the setting you selected on the aperture ring and you will see the viewfinder darken. It only takes a moment to do, and soon becomes second nature when you're used to shooting with Takumars.

I think the references to a "depth of field preview" earlier in this thread were intended to describe the operation of the Auto/Manual switch but used the wrong terminology. We should probably stick to calling it the Auto/Manual switch to avoid confusion.

[Docrwm]

What Dartmoor Dave said! Flanged adapters are a real pain. Getting a genuine Pentax branded M42-K adapter is hard but there are a couple of non-Pentax models that work well and allow you to use the lenses as intended at their designed focal length.

[Tonytee]

What Dartmoor Dave said! Flanged adapters are a real pain. Getting a genuine Pentax branded M42-K adapter is hard but there are a couple of non-Pentax models that work well and allow you to use the lenses as intended at their designed focal length.

I tend to believe it would be less cumbersome to just purchase another Spotmatic F or SP 500 or SP II. Many thanks to everyone for your assistance. Best wishes for the holidays.

Regards,

Tony