Search results for 'back focus' - page 1997
noise at iso100
So over the last month I have had my camera/lens back and forth to Pentax for front and back focusing problems. They say it is ok. I would suggest this: If you're concerned about your camera's focusing, may be useful. Find out for sure whether the camera is focusing properly, and fix it if ...
Posted by ChrisA on 31/07/2008 - 09:16
Not a problem, advice needed
We have a large powerboat race starting in Alicante in a few months and as I have never taken photos of fast moving objects I went down to a dirt track with a friend, his kids and quad bike to try it out. First of all I found out that the Pentax focus system doesn't seem too quick at tracking mov...
Posted by Mike-P on 11/08/2008 - 07:32
Not a problem, advice needed
As for Pentax focus speed, I can't say how it compares with other makes/models, but people shooting fast moving subjects will often pre-focus, and shoot when the subject reaches the plane of focus. I tried shooting motor-bikes moving at 150mph a few feet away at the IOM TT in June. The go so fas...
Posted by George Lazarette on 11/08/2008 - 08:17
Not a problem, advice needed
I was looking for the "TT" effect such as when they come round a corner and you see the background blurred but the bike itself pin sharp The camera absolutely has to be moving, to achieve this. [Edit: well, for it to be motion blur, which is very different from the background just looking out o...
Posted by ChrisA on 11/08/2008 - 09:43
Not a problem, advice needed
Depending on how consistent the boats are in where they pass you each time, you could manually focus on a certain corner or section of the circuit, and fire away as a boat passes through. If you can get the panning technique you get great action shots, and it also takes more skill than having a fast...
Posted by AlfaFoxtrot on 11/08/2008 - 10:11
Not a problem, advice needed
I reckon boats will be easier than quad bikes. You'll be a lot further away, so the relative speed will be less. you could manually focus on a certain corner or section of the circuit, and fire away as a boat passes through Not 'as it passes through' - just before. Concentrate on keeping th...
Posted by ChrisA on 11/08/2008 - 10:35
Fixing a busted lens
I have recently acquired a Pentax-M 1.7 50mm. It was a freebie and seems OK, apart from the front filter ring, which is loose and flapping about. I'd like to have a go at fixing it to use for flash portraiture on my K200D. Anyone know how to get these to bits (in a way that I can get it back t...
Posted by Sdeve on 14/08/2008 - 19:46
Fixing a busted lens
Whenever I take anything to pieces and put it back together I always end up with a spare screw!...........good luck my friend
Posted by beginner on 14/08/2008 - 22:13
Fixing a busted lens
I posted a how-to a while back, using a rubber pipe fitting from a hardware store...costs like $2.00
Posted by Don on 15/08/2008 - 02:45
Fixing a busted lens
For some reason, I can't read my original post, or the PM.:?: For some queer reason i get this sometimes. I just scroll up and then back down and the text appears.:? must be some sort of security feature or i have an intermittent blindness problem :lol:
Posted by Clarky on 15/08/2008 - 23:08
Pentax 55-300 problem (I think)
You could start by using a focussing test chart ( http://focustestchart.com/focus21.pdf ) or ( http://regex.info/blog/photo-tech/focus-chart/ ) or ( http://pentaxdslrs.com/newchart.pdf ). I haven't used it yet but my preference is for the last one as there is only one line of high contrast for th...
Posted by Mannesty on 16/08/2008 - 15:54
Pentax 55-300 problem (I think)
To test for back/forward focusing, the pictures of the test chart should be with the lens wide open, to make the depth of field as narrow as possible. Then you will clearly see where the actual focus point is.
Posted by ChrisA on 16/08/2008 - 17:07
Pentax 55-300 problem (I think)
Mine 55-300 has front focus problem (on K10D), -50um in debug mode helped me.
Posted by piotro on 18/08/2008 - 15:29
Pentax 55-300 problem (I think)
Not a lot wrong with that lens/camera combination. The centre line of the chart could/should have been closer to horizontal. The idea is that the numbers above and below the centre line should fade out of focus at the same rate in both directions with the centre line in sharp focus. It seems they...
Posted by Mannesty on 18/08/2008 - 18:53
Pentax 55-300 problem (I think)
This result is really great news. The best you could have hoped for. The conclusion: any focus issue you have with that camera/lens combo is entirely your fault. Congratulations - this means that for better photographs, you don't have to rely on crappy service departments, moronic fob-off cal...
Posted by ChrisA on 18/08/2008 - 20:20
Front/back focus; lens v.s. camera
I didn't want to hijack other similar threads yet hesitant to start another, but I'm curious as to how the lens can cause front or back focusing? I have adjusted my camera in debug mode and it seems to have solved most of my issues. Now I'm looking to get the 55-300 lens but read about some of th...
Posted by amoringello on 18/08/2008 - 16:56
Front/back focus; lens v.s. camera
I can assure you the lens does make a difference. When I tested my lenses on my K10D, I had some front focussing, some back focussing, and only one needed no adjustment. Actually, that one lens does need adjustment, but it needs two. My DA* 50-135mm lens BF's at 50mm, and FF's at 135mm. Go figure...
Posted by Mannesty on 18/08/2008 - 17:02
Front/back focus; lens v.s. camera
Oh, I trust ya. There has been enough talk about lens being an issue. But how? I just see the camera adjusting the lens to focus until a single point becomes sharp regardless of how long it takes for the lens to shift and settle into a good spot where the edge contrast is acceptable. There is ...
Posted by amoringello on 18/08/2008 - 17:41
Front/back focus; lens v.s. camera
but I just have trouble sleeping at night not knowing these important details. :roll: Me too. Given that even the virtually omniscient , it's a worry.
Posted by ChrisA on 18/08/2008 - 18:12
Front/back focus; lens v.s. camera
Same thing puzzles me Amoringello. And your reasoning is the same as mine. So, if anyone can elucidate, it would be most appreciated. :-) Dan
Posted by Daniel Bridge on 18/08/2008 - 18:13
