Nice pics, not super sharp, but impressive magnification. Does your 'scope track the heavenly bodies, or is it totally manual?

There also seem to be an awful lot of little grey/black dots, particularly in the bottom left of the last pic. Is this space debris, or does your sensor need a clean?

If you take a shot with your film camera, then transfer the lens to your new Pentax camera, you will see a difference in the images.

Image quality is largely influenced by the lens but there is a significant difference in the image size.

The image produced by a 50mm lens on a Pentax DSLR will appear to be approximately the same proportions, angle of view etc. as a shot taken with a 75mm lens on a 35mm film camera. A Pentax (and others) DSLR has an APS-C sized sensor, which is smaller than a 35mm frame.

That'll be K-x.

A Nikon user will always tell you Nikon is best. I doubt he asked you what you were going to use it for. Fast action sports, static Macro, landscape, portraiture, whatever.

We here are similarly biased towards Pentax, but we do concede that for certain situations, other makes can be better, but that comes at a price normally.

Pentax lenses are not hard to find at all, just search ebay and you'll see. Other than Pentax, all of the other independent makers produce Pentax fit lenses as well. Tamron, Tokina, Sigma, etc.

A Pentax DSLR is a very capable tool with some innovations not found on other makes. For instance, if you want image stabilisation on a Canon or Nikon body, you have to buy a lens with it built in, and they are suitably expensive. Most Pentax DSLR's have shake reduction (image stabilisation) built in to the body, so all and every lens you put onto it, benefits. Even 50 year old screw thread lenses can be used with a cheap adapter. Some limitations do apply, but they can still be used. Any lenses you have already can be used on any Pentax DSLR.

There was a time when Pentax was the preferred 35mm film camera of many professionals. Pentax lost their way a bit in the intervening years, but they are making up for it now.

If you fill in your location in your profile, we may be able to give you better advice about where to buy.

Me too. Nowadays I tend to take the shot, then put the settings right and take it again, properly.

I was never that careless with film.

Trouble is, you have only 3 variables that affect exposure. Shutter speed, needs to be high'ish, aperture needs to be small'ish (bigger f number), and ISO needs to be set appropriately to get the exposure right.

Master those, use a tripod to eliminate camera shake, and you've cracked it.

You have a PM.

Excellent instructions Matt, but I managed to do mine without taking it apart. I didn't drill the hole for the locking pin though.

I used a model making drill, like the Dremel, but with a fine and narrow grinding stone or glass etching bit, probably both. It did take awhile to remove enough of the metal to ensure the extra pin didn't short to the steel plate though.

I'll maybe revisit this and drill the hole for the locking pin. I hadn't actually thought of doing that because the locking pin is spring loaded and if the hole isn't there, it can't get stuck. It would give a bit better security to the fixing I guess.

It does make an awesome hammerhead gun though, which can still be used wirelessly if needed.

If you like that focal range, but would prefer auto focus, I can recommend the smc pentax-f 70-210mm lens.

With the manual lens that you have, I recommend setting the focus point selector to centre spot (it might do this automatically), focus on the animals eye(s), and ensure you have the green hexagon (focus confirmation) lit in the viewfinder.

Also, your lens will not give the best sharpness wide open You should stop down to around f8/f11/f16 for best sharpness.

If your images are still not sharp, you might have a back/forward focussing issue, which can be corrected.

Exposure and contrast seem to be better but its still not in focus. Look closely at the eye. It is that which should be in sharp focus.

I don't think you are using a fast enough shutter speed really. I would increase the ISO from 100 to 400 and use at least 1/320th sec for shutter.

Personally, I find the water at left and top uninteresting and I would crop it out leaving just a study of the duck itself, but it needs a sharper subject.

Good effort though. Practice makes perfect.

Which make/model 70-210mm lens do you have?