Search results for 'back focus' - page 2078
Lens design
Use black card from a craft shop to make a prototype. You may find that a standard food tin will be about the right size and shape, so make your prototype that shape and size (about 74mm diameter by 105mm high) The lens focussed at infinity and set to the minimum aperture will show up any vignetting...
Posted by Spotmetre on 01/10/2012 - 09:04
Lens design
There seems to be general light pollution with this shot. It has that yellow tinge from the streetlights, reflected back from muck in the atmosphere. I think that the yellow smears on the bottom and up the left hand side are clouds. About all you can do is adjust your exposure until the sky becomes ...
Posted by Spotmetre on 19/10/2012 - 13:57
Removing PF with Elements 10 or LR3
MattMatic - lens is DFA 100mm WR macro, so I hope I can't do better, but body is K20D, so could be time for a K-5 II(s?). SnoozeMoose - PSP x2. Tried to load it up again, but despite being a full retail version I keep getting a 'Trial version licence expired' message. Waiting for Corel tech suppo...
Posted by JohnX on 30/09/2012 - 17:19
Issues with DA* 16-50
I discovered something rather unstartling when I came back home to review my photos (it was too bright outside, so I couldn't spot it on the screen). This is a cutout from the 1.1 square (3x3 grid) of my image. What is it? My thought is that it is something that have gotten inside the le...
Posted by SnoozeMoose on 29/09/2012 - 17:48
Issues with DA* 16-50
Must be something on the sensor. I had similar problems a couple of months back and nothing showed up on any of the in-camera tests or by looking at the sensor itself, just on the photos. The cleaning kits aren't cheap, but do a very good job. The only other possibility is oil or something on the...
Posted by milamber on 29/09/2012 - 18:53
Pentax User Website
I only get noticeable trouble on this site. I won't say that I never have a problem anywhere else, but if I'm going to have trouble, it will be here. Same for me. The problem went away for a month but now its back. IE will sometimes recover the page but not every time. Les
Posted by 1947lcs on 31/10/2012 - 10:19
lenses for k5 issue
Hi Rob PK stands for Pentax K mount - if it says PK on the lens mounts (not caps)- they should work. There are a small number of older 3rd party PK mount lenses that will not fit the K5 due to the flange on the mount being a little too thick - but I have never seen this problem on a Vivitar. ...
Posted by fritzthedog on 02/10/2012 - 19:36
lenses for k5 issue
The Vivitar could actually be in a Konica mount, or something other than Pentax K. If you provide us with some images of the mount of the lens, we would be more suited to figure out why you do not seem to be able to get it working. Just remember to get it in focus, and include a good view of the...
Posted by SnoozeMoose on 02/10/2012 - 23:40
Balsam separation?
Balsam was used ages ago to join two lens elements. It has a refractive index same as glass so was very popular then. But aging affects the glue and separation starts from the lens periphery. This will show up as flare and blur around the edges. I had a Zeiss binocular with this problem. Just soake...
Posted by nanhi on 01/04/2013 - 07:28
AF on the Da 55-300
Having recently purchased, smc pentax DA 55-300 f4-5.6, Generaly I am realy pleased with it but have found at the 300 range AF goes haywire in certain modes (bird pics against bright sky). I have made sure (doubly) that object is in viewfinder,have even focused manualy but as soon as shutter is pre...
Posted by robwakefield on 08/10/2012 - 20:12
AF on the Da 55-300
With a 300mm lens you have to be holding it very steady for it to focus. It's no good if the point you are focusing on keeps changing. I use MF most of the time, if your photographing birds, branches can effect the AF and only MF will catch the bird. With AF focus on something further away manual...
Posted by Algernon on 09/10/2012 - 07:53
AF on the Da 55-300
You need to set your focus to centre point only for birds in trees or MF using the green indicator and beep.
Posted by Algernon on 09/10/2012 - 08:32
AF on the Da 55-300
I think that the AF can be de-coupled from the shutter button (though I've never done it). With this setup, you AF with another button and the shutter button only fires the shutter. This may help you as AF while tracking a fast-moving subject will be tough, especially with the 55-300, which has a ...
Posted by Jonathan-Mac on 09/10/2012 - 09:38
AF on the Da 55-300
I personally find against high contrast skies AFS works better than AFC as it does tend to hunt back and forwards as described at 300mm. I use centre point AF for all long tele shots. I generally use TAV mode at 1/500th and F8 when enough light allowing the auto ISO to correct restricted to up to 16...
Posted by wvbarnes on 09/10/2012 - 11:37
AF on the Da 55-300
Using the 55-300 on my K5,same body as previous, shooting against a very bright sky, with center focusing and switched to Mf, seems to have helped tremendously, especialy as the point of focus keeps changing, good ol mf. as to using the green indicator and beep, I know where you are coming from...
Posted by robwakefield on 09/10/2012 - 21:32
Pentax DA50mm f1.8 new lens green fringing
Also re 35mm vs 50mm lol Not to spark some massive one focal length vs another disscussion I wanted the 50mm mainly because it offers nearly an f stop better performace than the 35mm, this really helps freeze the kids in motion when shooting handheld, kids moving around without the flash! if t...
Posted by disco_1111 on 09/10/2012 - 23:59
Pentax DA50mm f1.8 new lens green fringing
Quite normal with some lenses. You get green fringing beyond the point of focus and magenta fringing on the camera side. This is a Pentax_A 50mm f/1.4 wide open: Don't go comparing lenses against the kit lens it's very good and will see off most primes :shock: and quite a few zooms :win...
Posted by Algernon on 10/10/2012 - 08:02
Pentax DA50mm f1.8 new lens green fringing
Algi's example is axial chromatic aberration where the different wavelengths are affected by distance (rather than across the frame). Both the FA50/1.4 and DA*16-50 show this when wide open, or wider than f/4. It used to be a right pain to correct, but Lightroom 4.1 onwards includes automatic rem...
Posted by MattMatic on 10/10/2012 - 09:11
Pentax DA50mm f1.8 new lens green fringing
It could be a focusing issue. Try a photo of a magazine with lettering on it at 45deg to see if any of the lines of type are in focus.
Posted by Algernon on 10/10/2012 - 10:05
Pentax DA50mm f1.8 new lens green fringing
Hi Guys Thanks for your help I have had a very quick response from Pentax - They want me to send them the Lens AND camera for them to take a look at! very happy with the quick response, not so happy about being without my camera for a week or 2! I think I will get the Lens exchanged by the ...
Posted by disco_1111 on 10/10/2012 - 10:05
