I have several photos that I take over and over again - they're dotted around the house and sometimes I take them handheld, sometimes with a tripod (think pot plants, clocks, kitchen sink, garage wall, etc). The point is, when I take these shots with various lenses I change the aperture values and after a while (several months usually!) patterns emerge.

From this I've learnt that my FA77 looks wonderful at f2.4, my FA43 at f2.8, my D-FA100 at f5.6 and my DA18-55 & DA12-24 both seem to be at their best at f8.

For sharpness I stand at one end of the garden and shoot the side of my house (with a tripod) trying to ensure that (a) the lens is at infinity, (b) it's parallel to the wall and (c) the brickwork fills the frame - this last one isn't always possible with wider lenses as my house isn't that big. Again, shoot with various apertures and compare them on-screen to see where the "sweet-spot" lies.

By the way, my favourite aperture for each lens isn't neccessarily the "sharpest". For instance, the FA77 is actually at its sharpest around f5.6-f8 but at f2.4 it has 99% of this sharpness and the most wonderful dreamy bokeh - hence 2.4's my favourite aperture with that lens.

Also, don't rely too heavily on the results of others - there are sample variations between lenses and one person's DA18-55 may show different characteristics to another's.

So in summary, it's mostly down to trial and error. Have a look through your previous pictures and choose the ones that you feel are really impressive - now look at the EXIF data for those photos and see if there's a trend there. If there is then you've found the strengths of your lens - congratulations!

I'm guessing the K-m's target market (people upgrading from digicams) are used to having everything done automatically for them so they won't miss the quick shift as the concept of focussing manually will be alien to them.

I won't be swapping my 18-55 Mk1 in a hurry either - I love quick shift.

I don't think there are any "bad" lenses in the current Pentax line-up are there?

So it depends what you want to do: zooms or primes / long or wide / fast or slow...? And how much you want to pay of course.

I think Matt's suggestions are pretty spot on for starters though.

Plastic mount and the dropping of the quick-shift mechanism unfortunately. Plus the "L" versions will be supplied without hoods (although I don't know if the weights quoted are with a hood in place or not ).

LOL!

Nice idea but I think that's even further from my "portability principle"...

Well done!

Looks like that one's mains powered rather than battery and it doesn't have the diffuser on the front - still, I can always make my own adaptations...

Cheers fella!

It sort of has that look to it I'll admit, but it's the results that count and it's perfect for my table-top needs. Several hours of scouring the web haven't turned up anything similar though so I'm now considering adapting a torch and a table-top tripod to build my own copy...

I picked up the following at the car boot sale today (the lamp, not the MX - that's there to give some scale) for the princely sum of 50p! Bargain!!

[IMG]http://i223.photobucket.com/albums/dd37/hefty1969/IMGP3164.jpg[/IMG]

It's mostly metal in its construction; swivels, tilts, goes up & down on a telescopic arm and all the barn doors are fully moveable. The light runs off 4 AA cells and is suprisingly bright.

I thought this would make a great light for macro work (which a lot of my photography is) but I've never seen anything quite like it before and I can't seem to find another like it on the 'net (I fancy a second to keep it company). There's no maker's mark and the only writing is the "camera lamp" wording on the lower door.

Has anybody ever seen one of these or know where I might find another? Obviously I'm not expecting it to be quite as cheap as this one was, but I probably would have paid the seller a bit more if he'd asked for it...

I'm planning on fitting a variable resistor so I can vary the output and tonight I'll be making some mini gels and gobos from sweet wrappers and black card - maybe a handkerchief softbox too.

Any and all help tracking down another gratefully received!

WOW! That really IS impressive!

Although the roll call of lenses used makes me wonder if he couldn't have bought a dedicated cine-camera cheaper...

All bodes well though, I'll be happy if the next Pentax I buy (when the K10 finally gives up the ghost some years from now) has a similar feature. I think this has just sold me on video mode!

Good find Clarky! Makes for some interesting reading.