Thanks: 0
Likes: 0
Needs Pictures: 0
Picture(s) thanks: 0
Results 1 to 4 of 4
Thread: Pentax lenses
-
5th May 2013, 02:35 PM #1
New Member
- Join Date
- Jul 2011
- Location
- sunshine coast
- Posts
- 1
Pentax lenses
Hi,
I am using a Pentax k5 digital camera with a SMC Pentax-FA f4.5-5.6, 80-320 lense for wildlife photo's but am not happy with the focus (or is it camera shake) even though I use a rule of thumb of 1.5 times the lense length as an aperture speed after also applying a 1.5 factor for the conversion from film to digital.
Using a tripod doesn't seem to help and I haven't been able to train the local wildlife to stay still for me. I generally use Tav to adjust settings so that I get a reasonable depth of field but to no avail.
I am considering the Pentax 60-250, f4, ED DA SDM lense but at $1400 plus want to know if this is a good choice or am I missing something with my current lens/camera combination or skills?
Any comments suggestions welcome,
Regards,
wingnut9x
-
5th May 2013 02:35 PM # ADSGoogle Adsense Advertisement
- Join Date
- Always
- Location
- Advertising world
- Posts
- Many
-
5th May 2013, 04:36 PM #2
When the student is ready, the Teacher will appear
- Join Date
- Jan 2006
- Location
- Telegraph Point
- Posts
- 3,036
With this lens, you are going to need as high a shutter speed as you can get out of your camera. Optimum sharpness will be around f 8-11 which means you will have to crank up the ISO in order to get the shutter speeds that you need.
Since the lens is 120-480-ish (in 35mm terms) I would be aiming for nothing under 1/500 sec as your workable shutter speed.
Persevere and see if this brings some better results
Cheers
SG.... some old things are lovely
Warm still with the life of forgotten men who made them ........................D.H. Lawrence
https://thevillagewoodworker.blogspot.com/
-
5th May 2013, 05:45 PM #3
SENIOR MEMBER
- Join Date
- Dec 2005
- Location
- Canberra
- Posts
- 3,260
Ummmm....if you are unable to tell the difference between camera shake and poor focus, a short course on camera basics might be your first starting point.
If your camera/lens has some form of electronic stabilisation, turn this OFF when the camera is mounted on a tripod (otherwise it can actually introduce blur into the image). A remote release can also reduce camera movement.
And start by setting it on an auto setting like 'sport' or 'fast action' and see if the camera can take better pictures without your assistance. Once you've got your baseline you can then start tweaking with whatever magic formulas you think appropriate.
-
15th May 2013, 01:05 PM #4
SENIOR MEMBER
- Join Date
- Sep 2009
- Location
- south of cultana
- Posts
- 516
As suggested part of the issue is ISO/sensitivity settings. It needs to be high and also look at aperture setting for depth of field.
One other thing is to set the focus setting to spot not a matrix one.
I am running the following:
Pentax K-m
Sigma 50mm F1.4 EX DG HSM Pentax Mount
Sigma 70-300mm F4-5.6 DG Macro
Sigma 28-70mm
Pic 1: Bird turning on rail
Autofocus spot
Focal length 300
Apeture F11
Sensitivy (ISO) 3200
Pic 2: Bird taking off
Autofocus spot
Focal length 300
Apeture F6.7
Sensitivy (ISO) 3200
Reply With Quote
Similar Threads
-
TIG - Gas Lenses
By Gavin Newman in forum WELDINGReplies: 1Last Post: 16th December 2012, 10:37 PM -
Manual Focus Lenses
By clubbyr8 in forum PHOTOGRAPHYReplies: 14Last Post: 17th November 2007, 09:35 AM -
Melting Lenses
By Chris Parks in forum WELDINGReplies: 8Last Post: 1st September 2007, 10:59 PM -
How reliable are autofocus lenses?
By bitingmidge in forum PHOTOGRAPHYReplies: 32Last Post: 31st August 2007, 06:22 PM -
Interchangeability of Canon lenses
By Rossluck in forum PHOTOGRAPHYReplies: 2Last Post: 24th July 2007, 05:05 PM
