All Forum Comments
Comment by Chrism8 posted on Sigma 600mm Mirror Lens at 28/08/2026 - 15:31
Comment by Chrism8 posted on Garden details at 23/08/2026 - 13:43
[quote:3496ace15f="LennyBloke"][quote:3496ace15f="walkeja"It could have been a very day of gale force winds blowing loose dirt around, stranger things have happened, I stand by my original comment, no sign of movement.
Comment by Chrism8 posted on Roche Grass Track racing at 20/08/2026 - 12:22
Great set.
Just to weigh in on the "blur to show movement" argument, for myself I prefer sharp because I'm often looking for detail that motion blur obscures. And I think the motion is entirely obvious in these images.
How long did it take to clean your rig? I do quite a lot of motorsport pictures and find that my gear often has a layer of muck/oil/rubber dust which is quite resistant to cleaning. That's also why I routinely have a neutral filter on my lens.
Thanks for your comment, a good hour or so to clean the kit, I did it that evening so to get it off pdq, the benefit of the 150 - 450 on a crop camera is I don't have to be tooooo close to the action but I did get hit by flying mud and of course the dust on several occasions
Comment by Chrism8 posted on Roche Grass Track racing at 20/08/2026 - 09:21
I had to add this one, tis what happens if you get a poor start and no time to recover the situation with just 4 laps to race
Comment by Chrism8 posted on Roche Grass Track racing at 20/08/2026 - 08:26
This was a championship event and the better riders / sidecar teams really stood out so after watching a few heats, I concentrated the lens on those guys.
Comment by Chrism8 posted on Roche Grass Track racing at 19/08/2026 - 10:41
The racing particularly with the more experienced bikers / sidecars was tough but fair, no mishaps but they got seriously close at times.
All K3iii with the 150 - 450
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Comment by Chrism8 posted on Roche Grass Track racing at 18/08/2026 - 13:21
Comment by Chrism8 posted on Wobbly hot shoe at 11/08/2026 - 08:01
It keeps the lens constantly focusing on the subject and stops any slight lag, I use it a lot for BIF
Comment by Chrism8 posted on Disappointed with results when using a Pentax 1.4 x convertor on a Pentax 150-450 lens at 26/07/2026 - 16:13
Roughly doing the same thing but without the light loss and slight extra weight.
The other thing is 1/500 sec is a tad to slow, based on rough suggestions your shutter speed should be more than your focal length.
So 450mm on a crop camera is 695mm without a tc so you'd need to be 1/800 sec minimum and roughly 1/250 with the tc
Comment by Chrism8 posted on Disappointed with results when using a Pentax 1.4 x convertor on a Pentax 150-450 lens at 26/07/2026 - 07:09
With the fixed aperture prob F8 I guesstimate you'll need 1/1250 sec for any chance of a sharp image in reasonable light.
Increasing the iso much above 800 / 1000 will have its own issues as well.