Search results for 'back focus' - page 1259
K-mount lenses on istDs.... probably stupid question
Even in a viewfinder, DOF preview is mostly to see if a background goes enough in focus to be distracting, or general stuff like that. You can't get a really detailed view. But DOF preview is an absolute prerequisite for any camera, for the above mentioned reason.
Posted by Arthur Dent on 12/04/2006 - 01:58
K-mount lenses on istDs.... probably stupid question
Just to make sure that we really are off topic... Many years ago I worked as an Assistant Film Cameraman at the BBC using both 16mm and 35mm motion picture cameras. Depth of field tables are essential in the film industry because you are 'pulling focus' all the time and it might be unnecessary t...
Posted by gartmore on 12/04/2006 - 17:50
K-mount lenses on istDs.... probably stupid question
Mannesty, I don't quite follow that hypothesis myself! If it were true, surely it could only be guaranteed to work properly with genuine Pentax lenses and even then, it would mean that you could never actually achieve perfect focus in AF mode. All lenses (Pentax and non-Pentax) I've tried on my...
Posted by Kimbo on 12/04/2006 - 18:10
K-mount lenses on istDs.... probably stupid question
A further thought has just occurred to me: I'm not aware of any lens that transmits it's focusing distance to the camera (ie. how far away the subject is) so each time you focus the lens, the camera would first have to adjust it to either the near or distant limit in order to calculate the amount...
Posted by Kimbo on 12/04/2006 - 18:24
K-mount lenses on istDs.... probably stupid question
:lol: just to though a bit of petrol on the fire auto focus cameras regardless of make don't focus perfectly :shock: !!! :evil: allow me to explain before you all jump up and down :twisted: because thay use contrast to focus the lenses arn't ground as fine as the old smc lenses which a...
Posted by ali studio one on 13/04/2006 - 11:50
K-mount lenses on istDs.... probably stupid question
Getting waaay off topic here ;) the mighty Matt ROFL! :D You can tell the *ist-D focusses at the hyperfocal distance when you use a parafocal lens. The focus is always off when you zoom, and it shouldn't be. Try the lens on a film Pentax (like the Z1) and the parafocal lens is fine. It wasn...
Posted by MattMatic on 13/04/2006 - 13:40
K-mount lenses on istDs.... probably stupid question
Well I still can't see it but I suppose Pentax may have designed cameras with multi-point AF to select an average between the distances detected. When the Canon EOS5 was tested, the user reported that the camera often decided to focus sharply on a point that was not the most important one and he ...
Posted by Kimbo on 13/04/2006 - 15:01
K-mount lenses on istDs.... probably stupid question
Multi-point autofocus is one of the most amazingly usless inventions in the history of technology. The camera doesn't know what you're trying to focus on! Stick witgh single point focus or manual, you'll save yourslf a lot of grief.
Posted by Arthur Dent on 13/04/2006 - 15:45
K-mount lenses on istDs.... probably stupid question
It's not down to multipoint AF. It's a question of how the SAFOX focusses. You'll notice that the *ist-D "knows" what lens is connected. Each lens has a 2-byte ID. In theory, it is possible for the camera to compensate for the given focal length/lens/aperture combination and focus on the H...
Posted by MattMatic on 13/04/2006 - 16:36
K-mount lenses on istDs.... probably stupid question
It's not down to multipoint AF. It's a question of how the SAFOX focusses. Matt Brings me back to my point - why bother with a contrast detecting AF system if it'll be over-ruled by an algorithm that give precedence to the lens information? Pentax design their cameras for use primarily with their ...
Posted by Kimbo on 13/04/2006 - 17:02
K-mount lenses on istDs.... probably stupid question
kimbo wrote As for AF lenses being deliberately designed to be less sharp than their earlier counterparts, I can't quite see that either and I don't think the MTF charts support that theory. all of the photographic press i.e practical photography amater photography digital photography the li...
Posted by ali studio one on 13/04/2006 - 17:05
K-mount lenses on istDs.... probably stupid question
all of the photographic press i.e practical photography amater photography digital photography the list goes on and on have at some point said "that autofocus lenses dont focus as sharp as manual focus lenses due to the fact that thay use contrast maybe pete could shed some light on this a...
Posted by Kimbo on 13/04/2006 - 18:25
K-mount lenses on istDs.... probably stupid question
Multi-point autofocus is one of the most amazingly usless inventions in the history of technology. The camera doesn't know what you're trying to focus on! Stick witgh single point focus or manual, you'll save yourslf a lot of grief. These are true words of wisdom. AF is OK in a happy snap situat...
Posted by gartmore on 13/04/2006 - 19:20
K-mount lenses on istDs.... probably stupid question
Multi-point autofocus is one of the most amazingly usless inventions in the history of technology. The camera doesn't know what you're trying to focus on! Stick witgh single point focus or manual, you'll save yourslf a lot of grief. ...why would you let something so crucial as focus be left to t...
Posted by George Lazarette on 13/04/2006 - 21:57
K-mount lenses on istDs.... probably stupid question
[quote:1bb16395de="Arthur Dent"]Multi-point autofocus is one of the most amazingly usless inventions in the history of technology. The camera doesn't know what you're trying to focus on! Stick witgh single point focus or manual, you'll save yourslf a lot of grief. ...why would you let something ...
Posted by Arthur Dent on 17/04/2006 - 03:13
Manual focus with *ist-D
Just a small thought: When using the *ist-D with a manual focus lens, I was getting a number of "off-focus" shots. Turned out I was instinctively relying on the red AF illuminator to guage focus. DOH! The red AF indicator is not a guide for focus - it's the green hexagon at the bo...
Posted by MattMatic on 25/04/2006 - 14:31
Manual focus with *ist-D
That's a good reminder. Thanks.
Posted by Arthur Dent on 25/04/2006 - 18:45
Manual focus with *ist-D
Matt, You have a choice ? :(
Posted by Mannesty on 25/04/2006 - 19:14
Manual focus with *ist-D
Hi Matt, I don't know about the D, but the DL allows you to switch on an audible beep when focus is achieved (for both manual and AF), which is accessed from the menu.. somewhere. It's useful in bright sunshine if you can't see the settings in the viewfinder very well. I'm just off out, b...
Posted by LiamD on 25/04/2006 - 19:53
Manual focus with *ist-D
Just a small thought: as I only ever use the centre focus point. After using my DS for a while I also ended up setting the camera to centre AF only as it seems a more natural and effective way of working most of the time. I have found a use for the multi-point AF though as it increases the hit ra...
Posted by niblue on 26/04/2006 - 10:31
