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K3 - Manual focusing - Techniques

andherTO
Posted 08/02/2017 - 14:01 Link
Hello everybody,
I'm using some M lenses on my K3 and my question is: what is the best way to precisely focus manually. Ok, I know using LV and magnification option or viewfinder plus red spots and sound alerts (not every time precise). II'm missing my old K1000's focusing screen system.
Are there any focusing screens for K3 that emulate the old system of matching the upper and lower part of the screen to obtain a perfect focused shot?
Thanks!!
johnriley
Posted 08/02/2017 - 14:53 Link
You can look visually for the highest contrast or the sharpest line. I never used the focusing aids, always preferring the overall ground glass screen.

There is a focus confirmation in the viewfinder, but it's not the red dot. It's the green hexagon at the bottom of the screen. When the green is steady, focus has been found. The red dot is only for showing the point the camera is focusing on.

The problem with fitting older type screens to AF cameras is that it may upset the accuracy of the AF, particularly the centre point.
Best regards, John
andherTO
Posted 08/02/2017 - 15:19 Link
johnriley wrote:


There is a focus confirmation in the viewfinder, but it's not the red dot. It's the green hexagon at the bottom of the screen. When the green is steady, focus has been found. The red dot is only for showing the point the camera is focusing on.
.

This is new for me. Thanks!
alfpics
Posted 08/02/2017 - 15:26 Link
johnriley wrote:
You can look visually for the highest contrast or the sharpest line. I never used the focusing aids, always preferring the overall ground glass screen.

There is a focus confirmation in the viewfinder, but it's not the red dot. It's the green hexagon at the bottom of the screen. When the green is steady, focus has been found. The red dot is only for showing the point the camera is focusing on.

The problem with fitting older type screens to AF cameras is that it may upset the accuracy of the AF, particularly the centre point.

I thought that AF is done via a sub reflector behind the mirror that deflects some light onto the AF sensor at the bottom of the mirror-box, in which case a focussing screen change won't make any difference.

link (Diagram on lhs near top of page - apologies as its a link to a Nikon page!)
Andy
Edited by alfpics: 08/02/2017 - 15:31
stu62
Posted 08/02/2017 - 15:28 Link
I think the best thing to do is find somewhere quiet and have a play
johnriley
Posted 08/02/2017 - 16:33 Link
alfpics, you're quite right.
Best regards, John
davidstorm
Posted 08/02/2017 - 21:49 Link
I know you don't want to use the rear screen live view for most work, but on the odd occasion that you do, don't forget the K-3 has focus peaking, which makes live view manual focusing very easy.

Regards
David
Flickr

Nicola's Apartments, Kassiopi, Corfu

Some cameras, some lenses, some bits 'n' bobs
pentaxian450
Posted 09/02/2017 - 01:24 Link
You can also use "focus trap" to trigger the camera's shutter as you focus. Using "focus trap" is sometimes the best way to nail focus on a moving subject. You just press the shutter button, then adjust the focus, and the shutter will release when the correct focus is reached. With moving subject, you can pre-focus an area which will be crossed by the subject, and the shutter will release when the subject reaches the pre-focused point.
Yves (another one of those crazy Canucks)
pgweber
Posted 09/02/2017 - 08:52 Link
pentaxian450 wrote:
You can also use "focus trap" to trigger the camera's shutter as you focus. Using "focus trap" is sometimes the best way to nail focus on a moving subject. You just press the shutter button, then adjust the focus, and the shutter will release when the correct focus is reached. With moving subject, you can pre-focus an area which will be crossed by the subject, and the shutter will release when the subject reaches the pre-focused point.

...which only works if the camera decides the subject is still in focus before it has moved off that point.
Peter

Pentax K5
Pentax DA 18-55 Mk1, 50-200 (Samsung), 16-45, 55-300 Mk1, 35 f/2.4
Pentax MZ6 + FA28-90, FA50 f/1.4, M 50 f/1.7
Tamron 80-210mm & 28mm
davidwozhere
Posted 10/02/2017 - 00:55 Link
I get it to work on the K5 but try as I might, it doesn't seem even to engage on the K3ii. Press the shutter release and it fires, no matter how you have set it.
Both the *istDS and the K5 are incurably addicted to old glass

My page on Photocrowd
microlight2010
Posted 10/02/2017 - 19:35 Link
@davidwozhere; did you set the AF mode on the K-3II to single shot AF.S?
K-3II - HD DA20-40 Limited, HD DA55-300PLM, SMC DA10-17 Fishy, AF201FG Flashy
JAK
Posted 10/02/2017 - 19:47 Link
davidstorm wrote:
I know you don't want to use the rear screen live view for most work, but on the odd occasion that you do, don't forget the K-3 has focus peaking, which makes live view manual focusing very easy.

Regards
David

It's pretty amazing that it is possible to use some of the oldest SLR lenses with the most modern of focussing methods without needing any special add-ons. How much tech allows for that?
John K
davidwozhere
Posted 10/02/2017 - 23:34 Link
microlight2010 wrote:
@davidwozhere; did you set the AF mode on the K-3II to single shot AF.S?

Funny you should say that .... ! I was certain that I had done so but clearly had not done it properly -- Yes, it works -- Duh !
Both the *istDS and the K5 are incurably addicted to old glass

My page on Photocrowd

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