Search results for 'back focus' - page 1646
AF microadjustment
Contrast AF works by doing more or less what you do as a human - it changes the focus by analysing the contrast of the image on the sensor. It doesn't know how far to change focus, but it keeps refining it until it is as sharp as it can get it. Phase AF is an entirely different kettle of fish. I...
Posted by karma mechanic on 08/11/2011 - 20:58
AF microadjustment
This instantly gives the exact direction of focusing and amount of focus ring's movement. Very clear. That was the point I'd been missing. Many thanks KM. So.. going back to the lens that's back focusing more than the K-5 adjustment allows... what's best to do?
Posted by ChrisA on 09/11/2011 - 07:46
AF microadjustment
So.. going back to the lens that's back focusing more than the K-5 adjustment allows... what's best to do? I've the same problem with some MF lenses. If you are talking about AF lenses you can use LV with Contrast AF.... it's very fast.
Posted by Algernon on 09/11/2011 - 08:16
AF microadjustment
So.. going back to the lens that's back focusing more than the K-5 adjustment allows... what's best to do? I've the same problem with some MF lenses. If you are talking about AF lenses you can use LV with Contrast AF.... it's very fast. Well I was rather hoping for something that would be a real fix...
Posted by ChrisA on 09/11/2011 - 08:22
AF microadjustment
Why would a manual focus lens need the AF adjusting? We turn the focusing ring until the image in the viewfinder looks sharpest and that's it.
Posted by johnriley on 09/11/2011 - 08:37
AF microadjustment
Why would a manual focus lens need the AF adjusting? We turn the focusing ring until the image in the viewfinder looks sharpest and that's it. Because the AF confirmation hexagon is just as useful with a MF lens as it is with an AF one - arguably more so in fact, since as you said yourself, many peo...
Posted by ChrisA on 09/11/2011 - 08:40
AF microadjustment
I've always used MF with 6x6 cameras... although when it looks in focus.. it's not really in focus from a critical POV that is :shock: By definition anything within the DOF looks in focus and you can't argue with that.... so if I have a subject at say 10m and and the DOF is from say 6.5m to ...
Posted by Algernon on 09/11/2011 - 09:56
AF microadjustment
Another reason to use AF with a fully-manual lens is Catch In Focus. The problem with DOF tables is that they assume a certain viewing size and distance of the final image, such that the out-of-focus areas are lost below the level of detail the eye can resolve at that range. If that image is blow...
Posted by karma mechanic on 09/11/2011 - 10:20
AF microadjustment
With a 35mm f/2.8 lens I even tried using LV at 10X to find the two points where a target a meter away went in and out of focus so that I could take an average of the two which would have been near enough the correct point of focus. I used a focus rack that had +/- 30mm adjustment, but it stay...
Posted by Algernon on 09/11/2011 - 10:36
AF microadjustment
... This instantly gives the exact direction of focusing and amount of focus ring's movement. It is that final part which can give the error - although it can work out how much to move the lens (so it is fast) it doesn't really know whether the image is in focus - it only knows what the analysis of...
Posted by ChrisA on 09/11/2011 - 13:01
AF microadjustment
Another use for the green hexagon is with M42 lenses. If it works OK you can leave the lens set at the working aperture i.e. f/5.6 or f/8 and still focus OK, because a lot of zooms are that aperture anyway. Try focusing a 28 to 50mm lens at f/5.6 visually and you will see what I mean about DO...
Posted by Algernon on 09/11/2011 - 14:00
AF microadjustment
Actually this begs an interesting question regarding MF lenses. Given that it's not the camera moving the focus to the calculated point, but the operator, would you expect the BF/FF errors not to occur? Or at least be consistent from lens to lens on the same camera? Errors will still occur, si...
Posted by karma mechanic on 09/11/2011 - 14:48
AF microadjustment
Why would a manual focus lens need the AF adjusting? We turn the focusing ring until the image in the viewfinder looks sharpest and that's it. Because the AF confirmation hexagon is just as useful with a MF lens as it is with an AF one - arguably more so in fact, since as you said yourself, many peo...
Posted by Dave-L on 09/11/2011 - 17:39
AF microadjustment
To be honest, I think it's expecting a bit too much for decades old lenses to give a reliable result with electronics that are designed and optimised for DA optics. In exactly the same way, exposure cannot be guaranteed to be accurate either. I think I will stick to using my eyes. Perhaps a 2z...
Posted by johnriley on 09/11/2011 - 18:16
K-5 electronic level
One of the reasons my first K-5 went back was the electronic level indicating a lean when it wasn't. Not that I use it much, but it annoys me when something doesn't work. It also seemed to be getting worse with time - though at the time I put that down to my imagination. However, I checked the le...
Posted by ChrisA on 10/11/2011 - 13:21
K-5 electronic level
Mine is consistently accurate. The one that went back for sensor staining also had an accurate level. I use it all the time.
Posted by Gwyn on 10/11/2011 - 15:50
K-5 electronic level
I noticed as well that the auto horizon correction function, which I have never used, went out at the same time so must use the same sensor. Yes, I'm sure it does. It must rotate the sensor by the amount the level detection thinks it's leaning. [sigh] This is a classic example of the way P...
Posted by ChrisA on 10/11/2011 - 17:45
K-5 electronic level
Mine has never been level, it's about 3 bars out and has been since I got it. I used to use the level on the K7 all the time, but I have not been able to use it on the K5 at all. Living in Doha it's not practical to send it back, unfortunately; I have been hoping for a firmware upgrade that allows y...
Posted by aliengrove on 10/11/2011 - 19:39
Got a new camera!!
Well after having bought several secondhand cameras, a couple had to go back as they were faulty, and then being pleased with my *ist ds that I bought, only to find out last night that the 6mp is not enough for the stock sites I am with (which I quite enjoy doing) I got really fed up with having not...
Posted by jacqui2 on 11/11/2011 - 15:13
Got a new camera!!
Thanks everyone, actually popped into local camera shop today and had a play with the kr as, buying it online, haven't had a chance to handle it, (only a few weeks back when I picked it up in store for a few minutes) have to say, I was very impressed, my husband eventually had to nag me to put it ba...
Posted by jacqui2 on 13/11/2011 - 01:01
