It's an old trick I learnt in the army Mike

Not that I ever was.

Seriously, this was as near as I got to freezing the props on a photo at Shoreham -

[IMG]http://i217.photobucket.com/albums/cc222/Oggy3323/Lanc.jpg[/IMG]

-that was at 1/3200 seconds.

Thinking about it, typical prop rpm would be about 2000, which would be 33.3 revs per second. Each revolution would be 360 degrees so that would be 12000 degrees per second. So an exposure of 1/1000 of a second would cover 12 degrees of movement of the prop, and 1/1600th would give you 7.5 degrees.

QED

Various Rob. If you right click and save them, the exif data is intact. Right click on the saved image and select "properties" or look at them with Photome.

Um - a substantial difference in price

Hi Rob

A few of mine from Shoreham with the 150-500 -

[IMG]http://i217.photobucket.com/albums/cc222/Oggy3323/1-2.jpg[/IMG]

[IMG]http://i217.photobucket.com/albums/cc222/Oggy3323/2-2.jpg[/IMG]

[IMG]http://i217.photobucket.com/albums/cc222/Oggy3323/3-2.jpg[/IMG]

[IMG]http://i217.photobucket.com/albums/cc222/Oggy3323/4-2.jpg[/IMG]

[IMG]http://i217.photobucket.com/albums/cc222/Oggy3323/5-2.jpg[/IMG]

Not as good as the ones I took with the DA*300, but they were never going to be. The originals are significantly sharper than I can post here.

I tried catch in focus at Goodwood. I was standing at a corner of the track and focused at a point on the corner then waited for the cars to come. Results not great. Possibly better with slower subjects.

Not sure if this helps you Max, but this is my Lowepro Flipside 400 with K20d and 55-300, and a DA*16-50 which is similar in diameter and about 15mm longer than your Sigma.

[IMG]http://i217.photobucket.com/albums/cc222/Oggy3323/P9030042.jpg[/IMG]

There is a bit of stretch in it so there is more room than the photo shows.

It is possible to get the K20, 150-500 (on or off the body), DA*300, DA*16-50, and 1.4 TC and still have room for whatever.

My settings/Website options.

I'd be interested to see how it fares against the DA*300.

Is the original before you resized it to post it sharp?

I have problems with pictures which start off pin sharp and by the time they have been resized, hosted and posted, turn to mush.

That's £20 less than SRS.

That decision should take several milliseconds then