But that isn't a precise measurement. A "held" item will be in reality waving about anywhere and everywhere. Your camera would need to be on a tripod and so would the CD for this to be meaningful.

I don't know how accurate your testing is, I don't mean that negatively, I just don't know what sort of error we are talking about in relation to any experimental error.

Focusing screens will be in correct register within certain limits, like every manufactured item there will be some leeway, but small errors will be covered by depth of focus (as opposed to depth of field). As with all experiments, there is also our own experimental error as mentioned above.

The key question is, are your pictures critically sharp? If they are, don't worry. If they aren't then you know what to do.

It's quite common to find people who have difficulty with manual focus. Experiments with MF cameras showed that when a given subject was focused on by different, or even the same, people, the amount of error was surprisingly large.

This is why MF cameras have focusing aids such as microprism spots or split image screens, or a mixture of the two.

I wouldn't assume that there's a camera error - if there was then all your pictures would be blurred. MF or AF.

Very careful setting of the dioptre adjustment is essential and for the short sighted it may be helpful to use reading glasses for cameras with no such adjustment. The optical distance of the image in the viewfinder is about 1 metre and you need to be able to focus at that distance.

Hope that helps.

We live in a town, but quite often get hedgehogs in the garden. I have read somewhere that they can travel incredible distances in one night, maybe up to 7 miles?

Interfit IR triggers are around £48 at Jessops and they just fire once, so should be ideal for the purpose.

How about using an Infra Red Trigger mounted into the hotshoe? These are great for studio flash (no cables to trip over) and might be useful for the purpose you have outlined.

Also, welcome to the forums!

Just as a reminder, can we avoid posting the same message in more than one area please.

I've deleted a few duplications recently because it does cause confusion and clutters the forums.

Your post will be read just as well in one location and will get a more coherent response as well.

Thank you.

The 18-55mm Pentax lens is an able performer, so if you want to upgrade the best choice is arguably the SMC Pentax-DA 16-45mm f4, which is a superb professional-quality lens.

The Sigma lens you mention has a very reduced focal length range compared to what you have already, so I'm not sure it sounds all that interesting. I'm not a fan of independent lenses either in terms of quality of results or quality of manufacture, although there are notable exceptions.

That sort of image happens all the time in the Riley household, and that's without any flooding...

Open Pentax Photo Lab manually and then go File>Open to get to the image files you want.

You probably have another program set as the default, but you can close that and open whatever you want.