All Forum Comments
Comment by ChrisA posted on Macro and "Trap Focus" at 16/08/2007 - 17:52
One of the clearest explanations of CA I've come across is at:
http://www.vanwalree.com/optics/chromatic.html
I'd never understood the difference between axial and transverse CA before, nor why CA sometimes manifests as fringing, and at others as separated colour bands.
http://www.vanwalree.com/optics/chromatic.html
I'd never understood the difference between axial and transverse CA before, nor why CA sometimes manifests as fringing, and at others as separated colour bands.
Comment by ChrisA posted on chromatic aberration at 12/12/2007 - 08:42
Quote:
Joke? This was an entirely serious suggestion.
In that case, please give me notice if you intend to make an actual joke. I thought this one was very funny.Joke? This was an entirely serious suggestion.
Still, Pete would just edit out the vignetting in Photoshop, hat or no hat...
PS, I thought San Miguel, though, rather than Fino.
Comment by ChrisA posted on Problem with my K10D not sure if its a fault ???? at 19/04/2007 - 18:28
Quote:
If you were wearing a wide-brimmed hat while taking the pictures, then that could account for the problem.
But if you weren't, it wouldn't.
G
There are some jokes that shouldn't be explained.If you were wearing a wide-brimmed hat while taking the pictures, then that could account for the problem.
But if you weren't, it wouldn't.
G
Comment by ChrisA posted on Problem with my K10D not sure if its a fault ???? at 19/04/2007 - 17:46
Quote:
Change your hat.
Move your thumb.Change your hat.
Comment by ChrisA posted on Problem with my K10D not sure if its a fault ???? at 19/04/2007 - 17:02
Quote:
(but DON'T TOUCH with your fingers
I second that.(but DON'T TOUCH with your fingers
The other day I got a painful jolt off my Dad's little Braun 260 BC (very basic, also pretty old - hence the 'BC', I guess) in the process of measuring its trigger voltage that turned out to be 210V.
Of course, holding the probes one in each hand.
In retrospect, it was a bit of a case of "well duh"!
Comment by ChrisA posted on Metz 45CT1 at 16/04/2007 - 23:54
Quote:
28-300mm would seem to be general purpose . . . on film. On a digital body, I doubt it's wide enough at 42-450mm equivalent angle of view. It's almost certainly too long at 450mm end for hand held use on other than a K100D/K10D body. Even then, shake reduction might be a problem if the lens does not communicate with the body correctly.
Personally, I would choose the 16-45mm + 50-200mm DA lenses to suit a 'general purpose' requirement. Your image quality will be far superior and I doubt you'll be needing to change lenses too often.
Interesting points. I've had quite a bit of practice now, hand-holding at 400mm (600mm equiv angle of view), and the K10's shake reduction is just fabulous.28-300mm would seem to be general purpose . . . on film. On a digital body, I doubt it's wide enough at 42-450mm equivalent angle of view. It's almost certainly too long at 450mm end for hand held use on other than a K100D/K10D body. Even then, shake reduction might be a problem if the lens does not communicate with the body correctly.
Personally, I would choose the 16-45mm + 50-200mm DA lenses to suit a 'general purpose' requirement. Your image quality will be far superior and I doubt you'll be needing to change lenses too often.
These were hand-held at 400mm, for instance, and quite heavily cropped too:
http://i162.photobucket.com/albums/t244/chris5gd/Public/Imgp2694s.jpg
http://i162.photobucket.com/albums/t244/chris5gd/Public/IMGP2683-2-1.jpg
(although I had to mess about a bit with the latter, to remove some purple fringing, as you may remember).
The problem I have at 400mm fixed is that if the subject suddenly gets a lot closer, 400mm is too long. But for any kind of distance, 200mm can easily be way too short.
So a zoom with 300mm at the long end seems to be a decent compromise. If it's close to the sharpness of, say the Pentax SMC 28-200 FA, which I've been getting used to in the last few weeks, it would be very useful.
The kit 18-55 will do me for wide-ish angle for now, I think.
Comment by ChrisA posted on K10 general purpose zoom choices. at 23/04/2007 - 18:13
Quote:
You can't really compare 2 zooms having such different ranges as 16-45mm and 28-300mm anyway, can you?
Well I wasn't trying to.. but there's no denying 28-300 is "general purpose". You can't really compare 2 zooms having such different ranges as 16-45mm and 28-300mm anyway, can you?
I'm not so bothered about slow, but I'd like to know if it's reasonably sharp, considering.
Comment by ChrisA posted on K10 general purpose zoom choices. at 23/04/2007 - 15:38
I realise it's not going to be in the 16-45's league when it comes to sharpness, but has anyone any experience of the Sigma DL Hyperzoom 28-300mm f/3.5-6.3?
Comment by ChrisA posted on K10 general purpose zoom choices. at 23/04/2007 - 14:50
Quote:
I didn't get that email or visit any other site but PentaxUser did seem to be down for about 24 hours - I kept getting the 'page could not be displayed' message.
I got the email too. The PentaxForums site does look quite nice now.I didn't get that email or visit any other site but PentaxUser did seem to be down for about 24 hours - I kept getting the 'page could not be displayed' message.
I must say, I do like vBulletin. Much prefer it to phpBB, this version anyway.
Comment by ChrisA posted on Got lost for a minute at 16/04/2007 - 14:35
EDIT: I can't seem to make trap focus work on the K10D, even with an old Vivitar manual K mount lens. Has anybody actually got this to work on a K10D?