I learned something about my K-5 II camera today . . .


Mannesty

Link Posted 15/07/2019 - 16:26
. . . and it occured to me that some others might not know what I discovered.

I was watching a tutorial about achieving ultimate image sharpness today. It talked about using a sturdy support, techniques for reducing camera shake when taking hand held shots, and also post processing techniques.

During this tutorial, the tutor, Hudson Henry, mentioned that when he was out and about shooting stuff that he mostly used Aperture priority and Auto ISO. He went on to explain that by doing so, the camera (a Nikon D810) automatically tracked the focal length in use and selected a shutter speed high enough to help towards reducing camera shake, nominally the reciprocal of the focal length of the lens multiplied by any crop factor.

So I thought I'd try out my camera to see if the same were true and Indeed it was. That was something of a revalation to me because I thought I knew my camera inside out and backwards. No matter what lens I put on the body (I tried DA* 16-50mm and DA* 60-250mm) using Av and Auto ISO, the camera always maintained a shutter speed at least as fast as the formula ((1 / lens focal length) * crop factor) in normal daylight lighting conditions.

Who knew? I certainly didn't.
Peter E Smith

My flickr Photostream

alfpics

Link Posted 15/07/2019 - 16:27
No - I hadn't realised that either - many thanks!
Andy

1stEverPentax

Link Posted 15/07/2019 - 19:40
alfpics wrote:
No - I hadn't realised that either - many thanks!

On the odd occasion I have used AV for aircraft I have always been pleasantly surprised that the camera seemed to have selected a fast enough shutter speed...I was half expecting slower speeds might be selected ruining the image...just put it down to luck.

Mannesty

Link Posted 15/07/2019 - 20:27
Correction to my formula notation above, it should read 1 / ( lens focal length * crop factor) not as I have written it in my OP.
Peter E Smith

My flickr Photostream

Mannesty

Link Posted 15/07/2019 - 20:29
1stEverPentax wrote:

On the odd occasion I have used AV for aircraft I have always been pleasantly surprised that the camera seemed to have selected a fast enough shutter speed...I was half expecting slower speeds might be selected ruining the image...just put it down to luck.

I haven't tested it further but I think the focal length tracking, for want of a better phrase, only happens when you use Auto ISO at the same time as Av.
Peter E Smith

My flickr Photostream

Chrism8

Link Posted 15/07/2019 - 21:23
Providing your shooting jets, the settings offered is probably fine, if your shooting anything with a prop, you'll ideally need a slower shutter speed than the cameras going to auto select to get some decent prop blur.
Chris

www.chrismillsphotography.co.uk

" A Hangover is something that occupies the Head you neglected to use the night before".

-------------------------------------------------------------
K1 - Sigma 85mm F1.4, Pentax 150 -450 F4.5 / 5.6, Pentax FA 24 - 70 F2.8

Sigma 100-300 F4, Samyang 14mm F2.8, Sigma 70-200 F2.8,

K5iis - Sigma 17 - 70 F2.8, Sigma 70 - 300 F3.5/F5.6, Sigma 18 - 200 F3.6 / F4.5.
Last Edited by Chrism8 on 15/07/2019 - 21:24

pschlute

Link Posted 15/07/2019 - 21:25
Mannesty wrote:


I haven't tested it further but I think the focal length tracking, for want of a better phrase, only happens when you use Auto ISO at the same time as Av.

Well, if you use fixed ISO and Av the camera is rather limited for choice !!
Peter



My Flickr page

1stEverPentax

Link Posted 15/07/2019 - 22:29
Chrism8 wrote:
Providing your shooting jets, the settings offered is probably fine, if your shooting anything with a prop, you'll ideally need a slower shutter speed than the cameras going to auto select to get some decent prop blur.

I normally use Manual or TAv for planes so not a problem. It might explain why my son used to get very good results on his K-S2 and currently on his EoS 7D using AV
though.

regards

Karlo

McBrian

Link Posted 16/07/2019 - 12:45
I thought this behavior was goverened by the ISO AUTO SETTING > AUTO ISO Paramerters (SLOW - Normal - Fast) on page one one the camera menu:



Cheers
Brian.
LBA is good for you, a Lens a day helps you work, rest and play.
Last Edited by McBrian on 16/07/2019 - 12:49

Mannesty

Link Posted 16/07/2019 - 18:56
McBrian wrote:
I thought this behavior was goverened by the ISO AUTO SETTING > AUTO ISO Paramerters (SLOW - Normal - Fast) on page one on the camera menu:

That is likely true Brian but the manual does nothing to actually explain properly what that setting does, not to me anyway.
Peter E Smith

My flickr Photostream

McBrian

Link Posted 16/07/2019 - 20:21
Page 85 of the K5/K5ii Manual:



The K1 manual adds a wee bit more info:


Cheers
Brian.
LBA is good for you, a Lens a day helps you work, rest and play.

richandfleur

Link Posted 16/07/2019 - 21:37
McBrian wrote:
I thought this behavior was goverened by the ISO AUTO SETTING > AUTO ISO Paramerters (SLOW - Normal - Fast) on page one one the camera menu:



Yes, was going to say just this.

Control over the exposure calculation is provided by this setting on the higher end cameras, and I absolutely love it.
Traditionally the speed settings always favoured lower ISO values, and often made up for this with longer shutter times, which introduced blur or movement in my shots (even on quite bright sunny days). I found the above setting when travelling in Vietnam, and it was a welcome revelation that I could influence this behaviour.

Setting this to fast meant I could take portraits etc without fear of blur and it was quite liberating not having to worry about this and finally having faith in what the camera would be selecting. Well worth looking into this setting, if you haven't really noticed it before.

McBrian

Link Posted 16/07/2019 - 22:09
IIRC It's been in top of the range menu since the ist*D, it used to be called "Program Line".
Cheers
Brian.
LBA is good for you, a Lens a day helps you work, rest and play.

JAK

Link Posted 16/07/2019 - 22:16
Just to point out that the 'Program Line' settings relates to the Program mode (presumably that mode only.) Peter's description of the AV + Auto ISO relates to aperture priority (Av) mode. That's actually really useful thanks.
John K

johnha

Link Posted 16/07/2019 - 23:45
The program line option goes back to the SFX (and arguably the P50). In program 'normal' the SFX would alter the program line depending on lens focal length (and show it on the LCD) but it wouldn't be able to match 1/focal length.

For prop aircraft I use Tv and 1/125th maybe 1/180th at a push, any faster will freeze them.
PPG Flickr
Last Edited by johnha on 16/07/2019 - 23:46
Add a Comment
You must be registered or logged-in to comment.