I just bought an M42 mount Takumar 200mm preset f3.5 lens, which is even better than expected.It's quite odd as it has 18 aperture blades. It's as sharp as any lens I own at f5.6, but when using focus confirmation I don't get results quite as sharp as I get in Live View. I was wondering if this is down to me or if there's anything about using lenses this old that affects focus confirmation, and if so, if there's anything I can do anout it. Or is it just wrong technique or something?

Thanks, Mike, will try that, if I can work out where to drill.

I have two of these adapters, one genuine Pentax and one one a copy. Both of them have a spring that locks into the mount on the camera so that you have to unscrew the lens and then remove the adapter. I've read in several places that removing this spring means you can leave the adapter permanently on the lens, which is what I would prefer to do. However, without the spring the adapters do not lock in place in the camera mount, and can rotate freely. This makes focusing impossible as the whole lens rotates. Does anyone know why this is, as the adapter looks identical to a PK mount on a lens? Is there a fix?

I hope those who think using Photoshop is cheating don't stoop to using polarisers, ND filters, or any of the filters or effects in their cameras....

If the rules of a competition specify how much an image can be manipulated, then that's a diffetent matter.

The Sigma 24mm super-wide II is probably the only lens I have that I'll never sell...

Not sure I quite understand? You mean the T mounts on the lenses were removable?

The power of X-rays used at airports for hand-luggage is a minute fraction of what was was used before digital cameras came along. It's better to carry your film in your hand-luggage, as it will receive much smaller doses of X-rays than it will if it is scanned in your check-in luggage (however, at most airports only about 10% of luggage goes through an X-ray scanner). The X-rays can only affect unprocessed film.

The horror stories of films ruined by X-rays on hand-luggage mostly predate the digital era. Some third-world airports still use quite old machinery, however.

Here's some advice from Kodak, albeit 10 years old.

Finally found what it is on the internet (I think): it's a T-2 mount, to fit some lenses made by Tamron in the 60's. I'll have to see if I can find any cheap ones to try them out.

I have just bough an M42-PK adapter from Percy on this forum, and it came with another, larger, screw mount adapter which screws into the M42 adapter. This evidently provides mounting for lenses with a larger screw-mount than M42. This adapter also has it's threads on the outside, so is obviously for lenses that have an internal thread. Does anyone have any idea what this mount could be?

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