[RioRico]

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Problem could be that even double foil wasn't strong enough. When I pulled if off, the pin had worn a hole through it. I'm a bit nervous about fitting the mount ring down over a triple layer of foil. I might have time over the weekend to try again. Not right now -- we just sold our old adobe house and we're packing up to go stay in nearby house for a few days, then drive back to our home base. The details are labyrinthine. 50-odd lenses are shoved into travel bags. So... we'll see.

[newarts]

Problem could be that even double foil wasn't strong enough. When I pulled if off, the pin had worn a hole through it. I'm a bit nervous about fitting the mount ring down over a triple layer of foil. I might have time over the weekend to try again. Not right now -- we just sold our old adobe house and we're packing up to go stay in nearby house for a few days, then drive back to our home base. The details are labyrinthine. 50-odd lenses are shoved into travel bags. So... we'll see.

Any degree of contact is good enough. I'm ok with two layers of foil and one has worked as well. I think maybe a single thin copper strand from a lampcord wire might work too.

The first time one does it the need for lifting the mount ring straight up becomes obvious as does using the pin to guide one in re-seating the mount ring.

You are successful when an f-stop appears in the viewfinder with a metallic based lens like a K or M type. In my experience foil that's been torn or punched through is often ok - so long as there is contact between the foil and pin.

I'll get back to you on how to handle K&M lenses.

[keyofnight]

Excellent… Here's a status update! I sold the Tamron lens to a fellow Pentaxian on the other side of town. (He shot samples using a K-x, and he drove my price down to $260—he drives a hard bargain.) I'm almost sad to see the lens go…every picture I shot with that lens reminds me of California. ;D

A few examples:





I just haven't used the lens in 3-4 years—I guess it had to go. (;

[Gareth.Ig]

I think I've found an A100/2.8 for pretty cheap. Hopefully $120 when everything is said and done.

I imagine the M and K series would give me problems for the same reasons you've mentioned: I rely heavily on the in-camera metering, I rely heavily on the two knobs for setting aperture and shutter speed, and I rely heavily on the green button to give me a quick shutter speed setting. —I find it's quicker (and simpler) than flipping through all the speeds myself. I just push point, hit the green button, and adjust from there.

These are the reasons I shy away from the K, M, and M42 lenses. Perhaps these things shouldn't worry me. (;

Here's a question… does the in-camera meter rely on the lens' aperture information? That's the real "make it or break it" for me.

I have both K mount (50 f1.7, 135 f2.8, 200 f4 & 300 f5.6) and A mount (A28 f2.8) lenses. I would generally agree that for lenses you will be using regularly, the A mount is a better option, but I wouldn't avoid K mount all together. The camera will meter with them using the green button and will work in Av mode at the widest aperture. They are a great option for in-expensively exploring other focal lengths (particularly 3rd party lenses).

[SyncGuy]

Ah... And i am thinking of giving up my K105 for an A100/2.8. Anyone interested? LOL!

Though i love the K105 much too...

[keyofnight]

First, I want to thank every everyone for your responses! Right now I've payed for an A 100 f/2.8, and I'm waiting for it to arrive. I got a very good deal on it, so I'm hoping it's in good condition!

After a little more thinking, I decided that I really need a ~35mm lens. I shoot mostly on an A50mm f/1.4, but that's ~75mm with the crop factor. It's often too long for photos on the street, so I end up taking more than a few steps back when I shoot in close quarters. Neither the A 28 nor the A 35 seem up my alley—I want something more interesting.

So now I'm thinking harder about those M42 lenses. I've been reading threads on the Russian-made Helios lenses: the Helios 33 in particular. These Helios lenses produce extremely strange "swirly" Bokeh effects, and I'd like something interesting like Helios lenses produce. Does anyone know anything about this particular lens? Can you guys recommend any other interesting M42 lenses?

Is it practical to leave an M42-to-K adapter semi-permanently attached to an M42 lens (making it a defacto K-mount lens)?—I've seen it done, but I'm not sure how well it works.

[newarts]

...
Is it practical to leave an M42-to-K adapter semi-permanently attached to an M42 lens (making it a defacto K-mount lens)?—I've seen it done, but I'm not sure how well it works.

It works well for me; I have 8 or more m42 lenses configured with an attached adapter and use them frequently.

Dave

[MSL]

It works well for me; I have 8 or more m42 lenses configured with an attached adapter and use them frequently.

Which type of adapter works best for this sort of setup?

[newarts]

Here's a selection from ebay... pentax m42 infinity | eBay

They are often referred to a "Flangeless" or Infinity focus. There is another type with a wide flange wich prevents it from focusing to infinity.

I've seen no correlation between price and utility with such adapters. In my experience they all work.

Remove the screw and spring clip; discard the spring clip & replace the screw - tighten the screw to secure the adapter to the lens.

Dave

[jeztastic]

That's correct - the lens does not report the f-stop or its range. Preset means you close the aperture to the setting you desire and it closes to that value right away, before focusing (although some focus wide open then change f-stop to shoot.). I do not find this to be a problem as I seldom use f-stops higher than f:5.6.

In camera metering works fine with the green button

I made an easy, reversible modification of my camera's mount so it thinks all lenses are "A" type. This lets P-TTL flash work properly with all lenses and allows me to set the proper lens f-number to be recorded in EXIF (adjusting the viewfinder's report of f-number has no effect on an m42 lens). I have found no downside to this mod.


Dave

I just want to clarify exactly the advantages this gets you. Do you still need to set the desired aperture on the lens, or will the camera stop if down properly if you leave the aperture on maximum?

So if I am shooting with my M50 f1.7 on my K5 in Av mode, I would leave the lens set at f1.7, set the camera to f8, and the camera will stop the lens down as if it were an 'A' lens?

Or set the lens to f8, and the camera to f8 too to get the correct shutter speed?

Cheers,

Jez

Edit - Ah, or do I leave it set at f22?

[abacus07]

I personally did not like my permanently mounted adapter. Most rear lens caps did not mount on it and at one point it stopped mounting to the camera. Bower adapter. If I'm shooting m42 then I'm shooting all m42 that day with the Pentax adapter. Others have had better luck than I. Are you sure this Helios 33 is available on the cheap? It seems pretty rare.

I also would recommend a 24/28 to pair with your 50. 35 is a nice single lens walkaround but it's still pretty close to 50 and I rarely use my excellent K35f3.5 because of this. A 24/28 is a natural change in focal length for me. Plus you can't crop to make it wider but you can always crop a little to make it longer. some of the best $100 lenses here are the Kiron 28mm and the Pentax K28f3.5. Others will have to comment on the Kiron. I think it was sold as Vivitar and possibly other brands.

[abacus07]

I just want to clarify exactly the advantages this gets you. Do you still need to set the desired aperture on the lens, or will the camera stop if down properly if you leave the aperture on maximum?

So if I am shooting with my M50 f1.7 on my K5 in Av mode, I would leave the lens set at f1.7, set the camera to f8, and the camera will stop the lens down as if it were an 'A' lens?

Or set the lens to f8, and the camera to f8 too to get the correct shutter speed?

Cheers,

Jez

Edit - Ah, or do I leave it set at f22?

If you have an M50f1.7 then you cannot control the lens at all from the camera. If you leave it in Av (actually every mode other than M) then your lens is wide open and it will take the picture wide open regardless of where you set the aperture ring. If you are in M mode then the lens will be wide open for focus and composition but will stop down when you take a photo to wherever the aperture ring is set. In M mode you are able to take a meter reading using the green button.

The advantage of an A lens is that aperture is recorded so you can look at it later. You can also use modes other than M mode. It also typically costs 2x a comparable M series lens. for some it is worth and for some they aren't interested. I'm drawn a little more to the K series which in some ways are designed a little better. The M/A series were designed to be lighter and smaller but in the end pretty much every tak/K/M/A prime is excellent. They made very few dogs and even the worst take very good pictures.

[newarts]

I just want to clarify exactly the advantages this gets you. Do you still need to set the desired aperture on the lens, or will the camera stop if down properly if you leave the aperture on maximum?

You still need to set the aperture on the lens and set the camera's aperture setting to its minimum with the ewheel.

I think the main advantages are that P-TTL flash works with non-A lenses and m42 lens exposures will be good.

I'm not sure if there's an advantage with K or M lenses; I'm waiting for an M lens to arrive so I can check it out & report back.

Dave

[jeztastic]

If you have an M50f1.7 then you cannot control the lens at all from the camera. If you leave it in Av (actually every mode other than M) then your lens is wide open and it will take the picture wide open regardless of where you set the aperture ring. If you are in M mode then the lens will be wide open for focus and composition but will stop down when you take a photo to wherever the aperture ring is set. In M mode you are able to take a meter reading using the green button.

The advantage of an A lens is that aperture is recorded so you can look at it later. You can also use modes other than M mode. It also typically costs 2x a comparable M series lens. for some it is worth and for some they aren't interested. I'm drawn a little more to the K series which in some ways are designed a little better. The M/A series were designed to be lighter and smaller but in the end pretty much every tak/K/M/A prime is excellent. They made very few dogs and even the worst take very good pictures.

You misunderstand me - I have plenty of A and M lenses and know exactly how they work, I'm asking @newarts about his mod.

[jeztastic]

You still need to set the aperture on the lens and set the camera's aperture setting to its minimum with the ewheel.

I think the main advantages are that P-TTL flash works with non-A lenses and m42 lens exposures will be good.

I'm not sure if there's an advantage with K or M lenses; I'm waiting for an M lens to arrive so I can check it out & report back.

Dave

Gotcha, thanks. Doesn't sound worth it for my purposes...