With a manual lens the camera will not fire if it is not in focus and set to AF. If you set it to MF it will fire, in focus or not.

In my opinion, every lens should be used with a lens hood, even with modern multi-coating.

This is not something that specifically applies to the 50mm f1.4, although there is a point in that the larger the front element of a lens the more essential a lens hood may become.

That's a very mysterious question which unfortunately will need some further explanation as it doesn't make sense as it stands.

Use a blend? Do you mean a lens hood?
Or something else?

The 16-45 should be significantly better, but only if you are producing large prints. If you were using both lenses say at f8 and only printing to 6x4 then you probably wouldn't notice much difference.

What sort of photography are you doing?

There's nothing to worry about with these Pentax primes.

All the 50mm lenses will give stunning results on digital. For those used to zooms this could be a revelation.

I am currently using the SMC Pentax-FA 50mm f1.4 and results are superb. Wide open it will be softer than stopped down, but it will still be useable and to be honest I wouldn't expect to shoot at f1.4 very often if at all.

The most effective way to convert to mono is by using Channel Mixer. Hit the Monochrome button and adjust the sliders for red, green and blue until you get the best mix.

This image is very much divided into two, the upper half being much brighter as well. A different composition would have helped. However, as it is, why not try selecting the top and bottom halves separately and adjusting them in different ways to get a better balanced effect.

You need to introduce more drama into the image and darkening the sky would help, but the foregraound needs to be adjusted as a separate entity.

Is that third one Bass Rock?

If you cast your eye upwards on this page you'll see a mention of Harrow Technical...

Any competent repair house should be able to clean your aperture blades and restore your M lenses to full function.

I had a problem on a card, formatted it on another K10D and that cured the problem on my own camera.

Perhaps a kindly photographic dealer would let you try the same?

I've removed the repeat of this question to avoid cluttering the forums. It's always appreciated if any post is only made once and not spread around the forums.

Hopefully someone will be able to help you, but in the meantime just measure the meter against others and if any adjustment is needed change the ISO/ASA setting accordingly.

For example, if your meter reads 1 stop over-exposure at ISO 200 then set it to ISO 400 and all will be well.

Hope that helps.