K3 questions.


aadixon

Link Posted 17/01/2014 - 13:27
So, I got my k3 yesterday, and updated the firmware. It's pretty fantastic so far. I'm still learning it, and I literally just figured out what I was going to ask on here (How to use the bracketing feature correctly).

So the little preview button (on the OFF/ON dial) is it just to save the hassle of deleting a photo if it wasn't how you'd like it to be? When doing that I see it saves it as a JPEG, but then gives the option to save it as a RAW after the JPEG is saved. So, does the K3 store the RAW information temporarily or what? Just wondering how it can save RAW if it shot JPEG, or if there is a difference in quality of that RAW file compared to if I shot RAW without the preview function.

-Aaron

johnriley

Link Posted 17/01/2014 - 14:21
The RAW data is still in the buffer and can therefore be saved at that time. It is the same as if you shot RAW and gives JPEG shooters the chance to save an occasional shot as RAW.
Best regards, John

Helpful

JAK

Link Posted 17/01/2014 - 15:17
aadixon wrote:
So the little preview button (on the OFF/ON dial) is it just to save the hassle of deleting a photo if it wasn't how you'd like it to be?

If you just do a preview the image isn't automatically saved at all - it's for testing your settings, only you get the option to save it which is sometimes handy - imagine only having a preview image that was unrepeatable but couldn't be saved! It is possible to customize that in the menu options to give an optical preview instead so you can see the depth of field through the viewfinder before taking the shot like some old film cameras used to have.
John K
Last Edited by JAK on 17/01/2014 - 15:18

aadixon

Link Posted 18/01/2014 - 06:40
JAK wrote:
aadixon wrote:
So the little preview button (on the OFF/ON dial) is it just to save the hassle of deleting a photo if it wasn't how you'd like it to be?

If you just do a preview the image isn't automatically saved at all - it's for testing your settings, only you get the option to save it which is sometimes handy - imagine only having a preview image that was unrepeatable but couldn't be saved! It is possible to customize that in the menu options to give an optical preview instead so you can see the depth of field through the viewfinder before taking the shot like some old film cameras used to have.

I know it doesn't save until I tell it to. I just wasn't sure what the point of it would be if you're already shooting RAW. As in, if I took a picture I could just redo it if I don't like the way it looks, not needing a preview button. I can see where I'll be very thankful for it at random times I am sure, such as a high shutter speed shot. I have my K3 set to the digital preview. I know it sounds like I'm complaining about the function, but I'm really thankful for it. I'm just making sure I understand how it works and what advantages it has so I use it correctly.
Last Edited by aadixon on 18/01/2014 - 06:41

ChrisA

Link Posted 18/01/2014 - 08:36
I've never seen the point of the function. You still use a shutter cycle, so why not just take the picture and delete it if it's no good, and then take another one that is?

Suppose it was a great shot, and then another great shot comes along, but you miss it because you have to save the earlier image first.

It's not as if the size of SD cards is limiting.

TBH I've never seen the point of the optical preview either. By the time it stops down significantly, the viewfinder is so dark and grainy that seeing the DoF accurately is impossible.
.
Pentax K-3, DA18-135, DA35 F2.4, DA17-70, DA55-300, FA28-200, A50 F1.7, A100 F4 Macro, A400 F5.6, Sigma 10-20 EXDC, 50-500 F4.5-6.3 APO DG OS Samsung flash SEF-54PZF(x2)
.
Last Edited by ChrisA on 18/01/2014 - 08:40

Steep

Link Posted 18/01/2014 - 09:20
The preview on the on/off switch is a 'depth of field' preview. The feature has been around on cameras since the first automatic iris was invented and works by closing down the iris to the f/stop you have set as long as you have it pressed. It's purpose is to let you check that everything you want in focus is in focus before taking the shot.

Algernon

Link Posted 18/01/2014 - 12:03
DOF preview (optical) is absolutely useless. It was a feature put on for the moaners. They used to complain that cameras such as the ME Super hadn't got it.

You can't even see the parts through the viewfinder that are IN FOCUS never mind the change from in-focus to out-of-focus

It's also unlikely that the small viewfinder image would have the same DOF as the one calculated for say an 8x10 print.

--
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi

Steep

Link Posted 18/01/2014 - 12:20
It's only useless if you don't have a use for it. Some examples of use for a dof preview would be in focus stacking or in portraiture where the subject is close to a background or object you don't want highlighted. Granted you need very good lighting to check focus when you've stopped down a lot but still...

Algernon

Link Posted 18/01/2014 - 12:37
That's fine in theory, but in practise......

http://www.slrgear.com/articles/focus/focus.htm

As this graph shows, manual focusing through the viewfinder was indeed a complete non-starter of an idea.

As I said earlier if you can't see where the point of focus is. you won't see where it goes out of focus. If you could all the people asking for full frame just so that they can have OOF/Bokeh backgrounds could just put the back of the subject at the change point from focus to OOF making the background very blurred...... Just not possible partly because DOF in practise doesn't follow the theory.

Even electronic AF systems struggle to detect a difference at f/5.6 and smaller.

--
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi
Last Edited by Algernon on 18/01/2014 - 12:42

CMW

Link Posted 18/01/2014 - 13:13
The DoF preview may not offer precision, but it is usually enough to give reassurance that the OOF object you have in the foreground of your pic as seen through the viewfinder using a lens's widest aperture will in fact be acceptably focused at the smaller aperture you've selected. It's obviously not of use on every shot, but it's helpful on some.
Regards, Christopher

ChristopherWheelerPhotography

Algernon

Link Posted 18/01/2014 - 13:34
CMW wrote:
The DoF preview may not offer precision, but it is usually enough to give reassurance that the OOF object you have in the foreground of your pic as seen through the viewfinder using a lens's widest aperture will in fact be acceptably focused at the smaller aperture you've selected. It's obviously not of use on every shot, but it's helpful on some.

More theory It's heavily documented elsewhere that modern screens are manufactured for brightness and not accurate viewing. They have extra grooves cut into the fresnel rings which can cause false images. Most people concerned about large aperture lenses and better viewing install Canon EE-S screens.

In the darkroom days it was well known that the only accurate method of focusing a negative was by looking at the grain through a grain magnifier.

--
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi

CMW

Link Posted 18/01/2014 - 13:55
No, not theory. This is my practice. I find the DoF preview useful, even on screens that are less useful for focusing than those I had on earlier SLRs.

You may want to tell me I'm wrong to do so, but I can at least tell you that I am not talking theoretically.
Regards, Christopher

ChristopherWheelerPhotography
Last Edited by CMW on 18/01/2014 - 13:57

Algernon

Link Posted 18/01/2014 - 14:17
Believe that if you want to

In practise you can't actually tell where a camera is focussed and where it is out of focus either through the viewfinder or on the screen as in this typical 50mm at f/5 shot. That's why most lens tests you see on the web aren't of any use. Each shot is actually focused on a different spot in most of them.
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi

kh1234567890

Link Posted 18/01/2014 - 17:12
Algernon wrote:
Believe that if you want to

In practise you can't actually tell where a camera is focussed and where it is out of focus either through the viewfinder or on the screen as in this typical 50mm at f/5 shot. That's why most lens tests you see on the web aren't of any use. Each shot is actually focused on a different spot in most of them.

With my superninja powers (and with a little help from the Canon EE-S) I can often tell what is going to be in focus and what isn't. Even if the thing I want in focus is outside the puny central phase detect autofocus area of a DSLR. On a good day I can even judge the depth of field



Post by kh1234567890, on Flickr

Pentax M 50mm f1.4 at probably f1.8 or thereabouts.
Flickr Stream

Algernon

Link Posted 18/01/2014 - 17:21
I've got a Canon EE-S screen, but haven't got round to
cutting it down for a K-5 yet.

Looks like RH could do with one in his Canon.......
Took all the trouble to do a 17 shot test with two
expensive 50mm f/1.2 - f/1.4 lenses and was about
5 -10 metres different with the distances as mentioned in
the comments. You can see it on the paving flags.
Sadly most Internet lens tests are like that

http://ricehigh.blogspot.com/2013/01/luxury-50mm-lens-fight-ef-5012l-vs-cz.html

--
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi
Last Edited by Algernon on 18/01/2014 - 17:23
Add a Comment
You must be registered or logged-in to comment.