Search results for 'back focus' - page 2033
Focus point
Quick Shift is the feature on most Pentax DA lenses that enables a manual focus tweak after the AF has locked, without having to switch anything into manual focus. It's especially useful in close up and macro work. I realy did not know of this thanks John and Stefan I will try this out for myself so...
Posted by philstaff on 18/07/2010 - 17:22
Back Focusing
It has been said there lens`s are back focusing or FF if you look at Dofmaster Dept of field charts it clearly shows point of Focus is never centre. 55mm lens f1.2 is 49% Front Focus 51% BF 55mm lens f16 is 34% Front Focus 66% BF 55mm len f22 is 29% Front ...
Posted by montyaus on 20/07/2010 - 16:44
Back Focusing
I think what you are saying is the there is more DOF behind a given focusing point than in front. This isn't what people are discussing when they refer to back focusing or front focusing. They are referring to the point focused on being inaccurate. What you have been reading confirms the "rule...
Posted by johnriley on 20/07/2010 - 17:08
Back Focusing
Thanks for that explanation, but some of the charts on another thread that I have seen indicated to me, the focus point was on centre of the chart, but was showing more in focus at the rear of the chart which could be normal, but I thought it was seen as being front focusing (can`t find the thread) ...
Posted by montyaus on 21/07/2010 - 03:29
Back Focusing
Thanks for that explanation, but some of the charts on another thread that I have seen indicated to me, the focus point was on centre of the chart, but was showing more in focus at the rear of the chart which could be normal, but I thought it was seen as being front focusing (can`t find the thread) ...
Posted by johnwhit on 21/07/2010 - 06:49
Back Focusing
To do an autofocus test you use the lens wide open. Make sure you use a tripod; S/R off; and use natural light. You will get misleading results if you do the test in your kitchen in the evening :D
Posted by pschlute on 21/07/2010 - 08:37
Back Focusing
And ensure the camera is using the central AF point! The thing about BF/FF testing is that it establishes the point at which where the camera/lens combination is *actually* focused, as opposed to where the camera *thinks* it's focused. You establish where it thinks it's focused by: - using ...
Posted by ChrisA on 21/07/2010 - 09:07
Back Focusing
Has anyone else found that the AF focus point shifts to the front or rear depending on whether you start focusing from the infinity setting or from the minimum focus setting on the lens. Greg
Posted by gregmoll on 21/07/2010 - 14:44
Back Focusing
Has anyone else found that the AF focus point shifts to the front or rear depending on whether you start focusing from the infinity setting or from the minimum focus setting on the lens. Greg I believe this is entirely normal.
Posted by flossie on 21/07/2010 - 15:32
Back Focusing
It is interesting that I have never read any were to use the lens wide open , when checking for focus,this would help me to get it right,maybe. When I cleaned a 600mm mirror lens and reasembled it, having moved all the mirrors and lenses I was worried about the focus, but checked it out on a corr...
Posted by montyaus on 21/07/2010 - 16:08
Back Focusing
You normally have to use the lens wide open to see the actual difference. If you can still see it when you stop down a stop or two you would be better trying it there as well. With some lenses there is a focus shift when you stop down, so it makes sense to try and do it at whatever aperture you use ...
Posted by Algernon on 21/07/2010 - 18:44
Light spot
Can anyone offer any help as to what the ligt spot is on the photos please just got back and all the photos from the shoot have this strange light spot. I have changed the lens on the camera and still this spot remains in frame. So it must be the camera against being a lens problem any help most wel...
Posted by philstaff on 21/07/2010 - 14:44
Light spot
Have contacted Samsung and arranged for it to be looked at under the warranty just my luck wanted it for the air show on Saturday as well. Ian Well IQ doesn't look too bad. Use it for the airshow and send it back after Saturday if you haven't got another body.
Posted by Mannesty on 21/07/2010 - 17:35
Light spot
Just a thought but it could be light bleeding in through the eyepiece. Try turning it off and leaving it in a dark room for a couple of hours. But to be honest I'd send it back ASAP. By law if you unnecessarily use a product after discovering a fault you have legally been considered to have 'a...
Posted by greynolds999 on 21/07/2010 - 22:35
Light spot
Just a thought but it could be light bleeding in through the eyepiece. Try turning it off and leaving it in a dark room for a couple of hours. But to be honest I'd send it back ASAP. By law if you unnecessarily use a product after discovering a fault you have legally been considered to have 'a...
Posted by philstaff on 21/07/2010 - 22:42
Light spot
I seem to remember someone else on the forum having a problem with a Samsung DSLR a while back and because they couldn't fix it or replace they offered the user a new NX10. May have been a different forum or just complete rubbish though :lol:
Posted by Mike-P on 11/08/2010 - 16:05
Light spot
Good memory Mike, I think you are reffering to this: https://www.pentaxuser.com/forum/topic/gx20-going-back-for-repair-19377/p-0
Posted by piotro on 11/08/2010 - 16:26
Light spot
Thats my worry Mike the lens mount is different on the NX 10, you can get an adapter but Im not sure how this will effect the cameras auto focus and the metering. I did try one out today but much prefer the feel of the k10 and GX 20. Ian
Posted by philstaff on 11/08/2010 - 17:47
Light spot
Hi Stefan I cant see my options being any different if I had contacted the store I suspect there offer will be the NX 10. I may hold out for a cash back offer though. Ian
Posted by philstaff on 11/08/2010 - 22:26
Light spot
That's the thing, I don't know how keen Samsung is on giving cash back offer since you didn't had a contract with them but I don't know the UK law.
Posted by Anvh on 12/08/2010 - 15:29
