From Stefan:
Personally, I would look for more. Earlier I suggested LG Flatron monitors. My current 22" has a sticker referring to 5000:1 Digital Fine Contrast. Just what that term means, I have no idea - I do know that the range between light and dark is more than I can rasonably detect.
Just be warned - the normal definition of Contrast used by vision scientists is one that (assuming it could be viewed) would give the contrast between totally white and dead black as zero - which is clearly wrong - and which gave me much fun when I used to teach HCI. Also be warned that perceived contrast will vary with changes in the ambient light. I changed the lampshade in my office/workroom, and then had to make and fit a diffuser to get things the way I wanted.
John asked for specific recommendations:
Get a Lenovo. That's Chinese from the factory that used to build for IBM. Not the greatest spec, but built like a tank. Comes with a 3-year on-site warranty. Team this with a LG Flatron monitor. You have a mouse and keyboard already. There you have a reliable functional system. Sort of a Volvo type of system. It will still be working well in 5 years time when everyone else is wittering on about upgrading. Look for model Thinkcentre A58.
Geoff

terje-1 wrote
Well, none of my main machines have that much RAM. In fact, all of them have only got just 1GB each (2.4ghz PC, 1.8ghz laptop, 450mhz Apple laptop, 400mhz Apple G4, and they all seem to cope with whatever I want to do.
Loading a Hi-quality .jpg into Photoshop 6 on the PC will leave me with around .5GB free - but then I could load that file before I upped the RAM by 50% to that whole 1GB (and never really noticed that it was slow).
Having said that, I am not into batch processing, I hardly ever have more than one .jpg or RAW open at once, and I spend more time thinking about what I am doing than actually doing it. The same goes for writing. The relevant expression seems to be "Your gas mileage may vary"
As a small digression:
Back when the computer comics (sorry, magazines) were telling their readers that the entry level machine was a 66mhz DX-2 486, over 60% of the machines in use in the USA were only 286s. The bulk of the US military did not change until Win98 made it neccessary.
Remember: If it works for you, then you have enough (that's why some airlines can still get by with 45 year old 747s).
Geoff

Work on the principle of "getting enough".
- 2GB of RAM is enough, more is better but not essential.
- Dual-core is enough (not many programs can use more).
- Any processor faster than about 2.5ghz is enough. Note that several of the quad-core processors run at around 1.7ghz - and that is noticeably slower.
- Any good graphics card is good enough (the super ones are really for so-called "gamers" who want TV quality action).
- A reasonable size (but top quality) monitor is enough.

Better yet, start with the monitor decision and work backward. The first thing is to decide if you need a matt or glossy screen. That is a personal thing, but it may affect all your other decisions. And, make quite sure that you can calibrate it easily (the one drawback of the one I use).
Geoff

Doesn't just stop with the lens mount, though.
Which auto-focus method are you going to use with your hypothetical U-mount?
From that, which shake reduction system will you fit?
The logical end is a factory in China (or maybe Transylvania) making camera bodies and putting "YOUR" badge on.
Geoff

I guess that you will get a lot of personal preferences (good and bad)so here is my 2d worth:
I used a LG (Goldstar) Flatron 17" (L1710B) for 8 years at work, and bought one for home use (four years ago). Last year I added a 22" LG (W2234S), passing the 17" to my wife.
Editing is easier on the wide screen - colour registration is harder. There is another problem with the wide screen if you want to run an old Mac with OS 9 on it - like it does not want to boot up - but that is not what you asked.
I would recommend a good used L1710B (comes with matt screen finish, which suits my tired old eyes).
Geoff

Cannot speak to the K10
I started with a DSLR with a K100 Super (keeping my MZ50) and changed to the K200D when I saw a new one at a very good price. As most folk here will tell you, any Pentax DSLR will take any Pentax fit lens. If your Vivitar lens is screw-drive autofocus, you can put it on the A setting and forget it. Remember two things:
- The sensor size effect. Your Vivitar will behave like a lens with a focal length of 50% more. Don't worry about this worry about this unless you have a problem hand-holding at a long focal length.
- There are a lot more settings you can apply on the camera. You will be tempted to play with all of them and forget about taking pictures. Get on with taking pictures and ask here if you have a problem.
From my own experience, the K100 is good (particularly with a firmware upgrade) but the K200D is better. The K10D and the K200D both have a 10mp sensor, if that really matters, but the big thing for me is that you can still get a Battery Grip for the K200 (and I did).
Hope this helps the decision.
Geoff

What a question, Andy (and not a nice thing to do to an old person!)
I relied on having a centre AF point and centre spot for metering for hand-held shots of the birds in our garden. Your question made me wonder.
So, out comes the K200D manual (again ) and the K20 may be different ...
- Setting Spot Metering measures the center of the viewfinder. That's clear enough.
- Using Select AF Point lets one choose the AF point but does not alter the choice of Spot metering. That's clear enough as well.
Conclusion - I'm all right.
I find a setting that allows Linking Exposure to AF Point, which seems to do what you want to do, down in the Custom Settings Menu, and with a default of OFF. Does the K20 offer you this?
So now you have made me wonder if I need to re-evaluate my choice of settings for more general work - and if so, what do I use? Thank you for that.

To take this one step further Emma:
Load up your P30 with a fast film (my choice was Fuji 400 ASA for many years) and work on adjusting the Aperture to get the Depth of Focus that you want. Do you want the background sharp, or artistically out of focus? Let the body work out what shutter speed to use. 400ASA will let you have a fair range of shutter speeds in the hand-held range. Then if you need a slower speed 'cos the sun has come out - you can hang a filter on the front. Start with the 50mm or the 135mm lenses - but not both until you have a handle on the technique.
This is the same sort of thing that Kris is advocating above.
Geoff

OK, Emma
They have your name on them.
PM me with an address.
Geoff

Three Jessops filter holders (same size as Cokin A) are surplus to my requirements. One has a 55mm adapter fitted. Free to good home.