The composition will often determine the best crop. But if it doesn't effect the composition, sticking to near the 'golden ratio' (1:1.61should give pleasing results. This ratio was discovered in antiquity to give visually pleasing looks. The rule of thirds is derived as an approximation of the golden ratio, and common camera formats tend to be close to it for similar reasons.

Recently I've had a shot where reflections forced me to take it from an angle that included annoying background elements. Cropping these out left a uncomfortable elongated ratio that didn't print well. However rescaleing the image back to the original ratio worked nicely. Giving an image very similar to what I'd have got with the camera a little higher, but with the reflection as I wanted it.
These days the crop doesn't restrict the final output ratio, as long as distortions are acceptable.

Well part of the query anyway. There's also the bit about getting the shades of black right, which is a bit more difficult!

Excellent as usual, My favorites are 5, 3, 9 & 10.
Rain can clearly add something to shooting motorsports, but on the few occasions I've tried it in the wet everything been obscured by spray. At the truck racing we couldn't see the near side of the track, let alone the trucks!
It wasn't much better at times on the way home from Oulton on Monday, but at least on the roads everyone stoppped in the heaviest rain, allowing me to grab my camera & snap at the flash floods (about 1' deep in places).

Nice meeting up again George!
Hope you managed to make good use of Simon's pointers and that you got off in time to relieve the grandparents.
Look forward to seeing some of your shots of deer leap from the track
Mike

Hi George
I'll be working there this weekend, so might be able to get you on the grid again
From the timetable it looks as if I'll be busy whenever the historics are out, which is a real shame - they add variety to the usual line up.

The magnification gained by extension tubes is dependant on the focal length being used. Those SRB tubes could give some significant magnifications with the kit lens, though the optical quality of any zoom will struggle when magnified like this.

I've brought several items sold as not working, which were brought for adapting and were effectively fine. In these cases the seller listed a known minor fault and said otherwise they were OK when last used, but not able to test fully now...
In such cases you have to very much play it my ear, and ensure the discount is sufficient for the risk.

In general I'd agree with Jeff's assessment. It's usually not worth paying to get them repaired.

IRND filters are just the same as standard ND filters for visual light use. The difference is standard ones have no effect n IR, which limits their usefulness for those shooting in IR.
Unless you have a modified camera the standard ones will almost certainly be fine for both film & digital. A few earlier DSLRs (such as the K100d) have weaker hot mirrors allowing some IR through to the sensor. Even with these I doubt you'd see any issues other than colour cast with standard ND filters.
Many cheaper ND filters do produce a noticeable colour cast which can be corrected for using CWB. It may be that the IRND ones are better in this respect. If there's not too much price premium they might be the better option.

You'll only get decent photography books round here if I haven't seen them first (or if I've already got the same edition).

Most photography books in charity shops are a little out of date, when it comes to digital hardware. However all the stuff on lighting, compostion, optics... is still the same.

I really MUST get round to donating some of my purchases back, to free up space on my book shelves!

Where abouts are you Mark? If your local I could donate some direct to you, but it's probably not worth paying postage on them - my last lot from e-bay postage was more than the books.

Stunning shot Johan!
The darker 'shadows' under the eyes don't look consistent with the lighting of the remainder (which looks like a ring light). Any ideas on what causes this feature?