That's just about right except your changes do not actually change the original raw file. Instead, your changes are stored in a separate place and only take effect when viewing the image within whatever raw editor you use.

Then, if you export/save that image as a JPG, your changes are incorporated into it before the export in much the same way as shooting JPG in the first place.

The main difference is, when you shoot raw, you have much more latitude for changes afterwards.

That said, some here shoot JPG all the time with no issues, but they may have never got the WB wrong (or at least will admit to it).

What . . . never? As in . . . not at all . . . ever?

Do manufacturers apply grease to camera/lens mounts? I think it's unlikely. Why spend good money on gold plated contacts, then cover them in grease. Sorry Don, I don't buy that one.
I'd agree that the weather seals between lens and mount should prevent the ingress of atmospheric contaminants, but what about the small particles of chromium dust caused by metal to metal contact when lens changing?

I got sooooo frustrated with my K20D + DA* 16-50mm lens last night. I nearly launched the thing and promised to go to the nearest Canon/Nikon dealer as soon as I could.

I was shooting the start of the 'Moors and Christians' fiesta in Murcia, Spain. Amidst other 'togs with a range of kit including a Fuji Finepix, Canons, and some Nikon big guns. One guy had a Canon 1DS MK? with a lens on it that looked like a 5 gallon oil drum, geez it was huge.

Anyway, I was using an AF540FGZ flash with Sto-Fen Omnibounce and on several occasions during the latter part of the evening the shutter absolutely refused to fire occasionally (an issue I have had before I hasten to add). When it did, the shutter speed was so slow that I got blurred images, but the exposure was OK thanks to P-TTL.

Now I'm not used to, and have no time for, kit that doesn't do what I want it to, when I want it to (all batteries were charged before leaving for the event).

Then it occured to me, I haven't cleaned anything except sensors for a while and I did change lenses a couple of times during the evening, and the problem only occured after the last lens change.

Today I applied a few drops of WD40 to a lint free cloth and began cleaning the camera and lens mounts. I was stunned, amazed, and horrified (all at the same time) at the amount of grey metallic crud that appeared on my cleaning cloth.

I then went on to clean all my lenses and both cameras and all of my flash hot shoe mounts. I even cleaned the two SDM power contacts inside the bodies and on all my SDM lenses. All produced some dirt in varying degrees.

I haven't really got to the bottom of why the shutter din't fire, but I'm guessing this dirt had something to do with it.

So, how often do you clean yours. My answer is, When I suspect a problem. In last nights case, it was too late and I missed a few good shots.

And a reflector has only one spring loop, a light tent has 4. Don't plan on having any more children if/when you buy one.

Ebay light tents are fine for the work you want to do, and not flimsy at all. Wait until you try and pack it all into it's bag, it'll fight back.

I have one and it's superb. Mine came with red, black, blue, and white back cloths, just about all you need really.

Nothing wrong with your camera, and it's a good job you were shooting raw, because now you can change the white balance to whatever you like.

Give it a go, edit a raw image that has the wrong white balance and change it to what it should have been. You'll see what I mean.

The RAW image is just that, data taken straight from the sensor. The image file also stores whatever other settings you may have applied, like WB, and re-applies them after importing into your chosen RAW editor where you can change things if you got it wrong at capture time.

This is already available. If you marry a Pentax DSLR to a SMCP-F 1.7x AF TC and a DA*300mm, you have the 35mm equivalent FOV of 765mm at a fraction of the probable cost of a 600mm lens. I doubt you used anything longer in the days of film.

From where does this information originate? Available? Where?

Excellent day to have an open day, it's my birthday but I'm afraid I will not be able to attend. Having shelled out an enormous amount of money to have a number of female feral cats spayed, I can't afford any more toys for a while.

Have a great day Chris.