Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
05-02-2011, 08:37 AM   #16
Veteran Member
sterretje's Avatar

Join Date: Dec 2008
Location: Roodepoort, South Africa
Photos: Gallery | Albums
Posts: 3,534
Without knowing the ins-and-outs of your camera, it can be achieved with the 2 second timer and any Pentax dSLR. When you take a photo, the mirror will go up, the camera will wait 2 seconds to allow vibrations (shake) to dampen out and only then take the photo. This will also switch the SR off.

The K5 has another function as well. The first time you press the shutter, the mirror will go up and the second time you press the shutter the actual photo is taken (use a remote for this else it defeats the object); I'm not sure which other models have this functionality.

Pentax advises to switch SR off when using a tripod. Enough reason for me to do so Some people state that they don't notice a difference, others state that they do see a difference. The basic idea is that on a tripod there is no shake and the SR will try to compensate for it resulting in shake (and therefore blurred images).

05-02-2011, 08:54 AM   #17
Inactive Account




Join Date: Dec 2008
Location: Ames, Iowa, USA
Photos: Albums
Posts: 2,965
QuoteOriginally posted by sany Quote
...
1. small aperture=more depth of field (presumed all or most in focus) + also can focus to infinity
2. large aperture=shallow depth of field (presumed the focus area to get more in focus than the rest)
....
Add one more to your list:

3. Increasing f-stop beyond f:11 or so decreases sharpness in proportion to f-stop.
Sharpness is usually best around f:5.6-f:8.

There is nothing you can do about it with a single photo taken with your camera; it is the result of natural law limitations related to optical diffraction.


You can use a technique called photo stacking if you need the absolute best focus for a very large depth of field... the technique uses multiple photos to gather the necessary data to figure out the best focus at each position in space. In practice you take a bunch of photos at f:8 focused at differing depths and combine them with software. It isn't difficult.

Try http://www.heliconsoft.com/ freeware for example

Last edited by newarts; 05-02-2011 at 09:00 AM.
05-02-2011, 09:03 AM   #18
Veteran Member
steve1307's Avatar

Join Date: Mar 2010
Location: Sydney
Photos: Gallery | Albums
Posts: 1,129
QuoteOriginally posted by Capslock118 Quote
I'm wondering the same things. I doubt my K100d has the option to mirror up.
what he means is

Use a tripod (for stability at lower shutter speed) AND do one of the following

1. use Mirror lock up" (for eliminating blurring from the mirror shaking) - setting this mode disables the SR

or if you don't have M L.UP mode
2. have SR turned OFF because you're on a tripod.


Remember, having SR turned ON when you are mounted on a tripod increases blur because it tries to compensate for vibration that is not there.


If not mounted on a Tripod then keep the SR ON.
05-02-2011, 09:09 AM   #19
Pentaxian
Marc Sabatella's Avatar

Join Date: Sep 2006
Location: Denver, CO
Photos: Gallery
Posts: 10,686
QuoteOriginally posted by sany Quote
Thanks all for that knowledge sharing, but all these are really going over my head. I am getting stuck and confused with DOF and Sharpness (sharpness or focus!?)
My suggestion is to visit your local library and check out a good basic book on photography - I'm sure whatever they have will be fine. The basic concepts of aperture and DOF haven't changed in over a century, and pretty much any book should be able to explain it well and with pictures. There are any number of web sites, too, that can explain the basics.

QuoteQuote:
1. small aperture=more depth of field (presumed all or most in focus) + also can focus to infinity
You can always focus to infinity; doesn't matter what the aperture is.

A small aperture (large f--number) *does* means more that is in focus. But "in focus" is a relative term. Just because the background is more in focus at f/16 than at f/8 doesn't mean it is as perfectly in focus as if you actually focused on the background - and if you did that, the *foreground* wouldn't be as perfectly in focus as it would be if you focused there. The areas you didn't focus on might be "in focus" enough to look OK in a small print, but that doesn't mean they will look perfectly sharp when you zoon in to 100%. I'd say that's true of your posted picture. I'm sure you see flaws when you zoom in to 100%, but at the posted size, which corresponds to about a 4x6 print, it looks just fine.

QuoteQuote:
(what does Shake Reduction do negative, I was thinking it only helps us to reduce reduction)
The conventional wisdom is that SR was deigned for the large/slow motions of a shaky hand, not the small/fast vibrations that can occur when on a tripod, and that SR can be counterproductive. Over the years, people have tried to prove or disprove this claim, with varying degrees of success. But the manual *does* say you shold turn off SR when on a tripod. This happens automatically is you use the 2-second timer, hich is designed to flip the mirror up 2 seconds before the picture is taken, to reduce that source of vibration.

05-02-2011, 02:11 PM   #20
Site Supporter
slip's Avatar

Join Date: Oct 2006
Location: 2 hours north of toronto ontario canada
Photos: Gallery | Albums
Posts: 3,533


your camera might be close to these..





link to the full tutorial

Question Aperture/Shutter relationship!!? - Digital Scrapbook Place

hope this helps

cheers
05-02-2011, 04:17 PM   #21
Inactive Account




Join Date: Dec 2008
Location: Ames, Iowa, USA
Photos: Albums
Posts: 2,965
QuoteOriginally posted by slip Quote

your camera might be close to these.

link to the full tutorial

Question Aperture/Shutter relationship!!? - Digital Scrapbook Place

hope this helps

cheers
Helpful except for one error in the first image; sharpest should be between about f:5.6 & f:11

I know you are not responsible here and I appreciate your posting helpful stuff but feel it it is important to not let errors persist regardless of their source's authority.

Also Tv and Av may be easier to remember as "Time value" and "Aperture value".
05-02-2011, 05:19 PM   #22
Site Supporter
slip's Avatar

Join Date: Oct 2006
Location: 2 hours north of toronto ontario canada
Photos: Gallery | Albums
Posts: 3,533
QuoteOriginally posted by newarts Quote
Helpful except for one error in the first image; sharpest should be between about f:5.6 & f:11

I know you are not responsible here and I appreciate your posting helpful stuff but feel it it is important to not let errors persist regardless of their source's authority.

Also Tv and Av may be easier to remember as "Time value" and "Aperture value".
what is meant in the chart that the backgroud blur/ sharpness is a progression, not an exact setting.
thanks for the time value, apeture value tip, I am going to use that myself to remember

cheers
05-05-2011, 07:49 PM   #23
Veteran Member
PGillin's Avatar

Join Date: Apr 2010
Location: South Florida, USA
Photos: Albums
Posts: 337
Let me be captain state the obvious-

In any kind of wind grass and trees will move. Depth of Field, Tripods, SR, AF, Primes, Etc. WILL NOT change that. Slight unsharpness on blades of grass or a tree is quite normal.

While all the tips mentioned so far are valid, they WILL NOT correct subject movement, only camera/photographer issues. Ansel Adams could not coax a sharp picture out of a Zeiss lens if he was shooting a forest on a windy day....

Just make a note of this before you have a bout of Gear Buying Syndrome over a few landscape shots.

05-06-2011, 02:40 PM   #24
Moderator PEG Judges
Kerrowdown's Avatar

Join Date: Aug 2008
Location: Highlands of Scotland.
Photos: Gallery
Posts: 32,726
QuoteOriginally posted by sany Quote
help me improve sharpness
Just to add a quick bit from me, to go with all the other good advice already given on this post. I note the shots were taken in Dubai, UAE, whilst this is a most beautiful part of the world , it does have some drawbacks for photography.

I can remember from my time in the Middle East that certain other factors come into play, purely due to the geographical region your in. While you can not totally eliminate them, by altering your photography technique a little you can minimize their effects.

Firstly there's atmosphere i.e the level of dust/sand in the air, this can play havoc with both contrast and apparent sharpness, especially for distant buildings and objects far away. Seldom will you get a totally clear day, but some days are certainly better than others, days of low wind and especially great opportunities just after rain when the dust has been laid down. Try and pick these days for your more critical photographs.

Secondly heat haze, you know that kind of shimmer effect, even when not visible as shimmer it's often still present, again it plays havoc with both contrast and apparent sharpness. Try to take your shots at the cooler times of the day, which are usually at either end of the day i.e. morning and evening (it's often then, that better lighting conditions present themselves too).

You notice I used the term "apparent sharpness" on both examples above, that's because even with the best equipment in the world in terms of its ability to resolve sharp images. If the object your taking ain't sharp for the reasons above, the lens can and will just resolve whats there.

Also remember to enjoy your photography too.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, pentax help, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Suggestion Please improve the search capability switters Site Suggestions and Help 14 11-28-2009 04:41 PM
Sharpness VS Fine-Sharpness in k20d wasim_altaf Pentax DSLR Discussion 8 10-12-2009 11:41 AM
How to improve my bird shots? Tristar Post Your Photos! 4 09-22-2009 08:24 AM
Sharpness vs Fine Sharpness on K20D morfic Pentax DSLR Discussion 2 11-02-2008 10:13 AM
Fine sharpness and sharpness move together on K20D 1.01 morfic Pentax DSLR Discussion 2 07-11-2008 09:18 PM



All times are GMT -7. The time now is 02:04 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top