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K10, blur pictures with older lenses, what am I doing wrong?

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Fraulein

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Hello, I just got my K10 yesterday. I have still a lot of reading to do. I took some pictures with my new lens, Pentax 100 mm Macro 2.8f. It seems to be working pretty good.

I also took some pictures with my old K mount SMC Pentax 55 mm 1.8 f. But all the pictures seems to be out of focus. I have been using this lens for many years with my Pentax K1000 and I used countless rolls of films. I never had any trouble getting sharp and crisp pictures with this equipment. So, I figure I know how to get the picture on focus on the focus screen. But with the K10, even if the image was perfectly in focus in the viewfinder, the image was still out of focus...I am confused. I tried many different settings even with a tripod and the shake reduction off it was stil out of focus.

I think I followed the instructions properly. I put the mode dial knob on manual. I put the focus mode lever on manual focus mode. I push the green button to get the right speed setting for the aperture I choose.

Any ideas??

Thank you
 
Do you get any focus confirmation in the viewfinder? You could also try focus trapping - set the AF/MF knob to AF.S and the shutter won't trigger until the AF system thinks it has a lock.

Also also, check the viewfinder diopter setting. See if the subject appears sharp in the VF right when the AF has locked on and if it also is in focus in the resulting image.
--
/ Richie - http://www.p-i-x.net
 
I have been having the same problem; I made some posts here about it,

but no one seemed to have any definitive ideas that nailed the problem. It is still an issue for me, so my 17-70 stays on most of the time. (Bloody disappointing I can tell you!)

CR kennedy have said they'll send the camera off and check it out with my 1.4 lens on... but it means a long trip to the city and 10 days (according to them) without the camera - so wont be doing it anytime soon.

I dont remember having this issue with my DS. When I went back and checked my old images most of the them looked fine.

I have a feeling its something to do with the wide 1.4 glass and the 10MP sensor and/or associated processing. (I should say I was using adaptors with old screwmounts BTW). I can get decent enough images stopped down F4 onwards... but its not a fast prime anymore! On my old SPII it was damn sharp with fabulous bokeh almost all the time...spread eagle at 1.4. Have some wonderful old concert pics that I usually set at [email protected] almost all the time... with fabulous results.

I seriously doubt it is the dioptor... as was suggested to me as well. Am relieved to hear some else has had a similar issue as I think some folks may have thought I was basically inept.
Hopefully we can both have this issue resolved at some point. NogBoy
 
...oh yeh, lots of focus confirmation. Tho it does go off before and after
what I reckon is absolute focus. (Have done all the tests believe me!)

Images appear to be absolutely pin sharp in viewfinder but image rendition is... in most cases...pretty grim. Of course we're talking wide open and near to... but its beyond normal taking into account the usual variables- low shutter speed, small DOP, slack focussing etc etc. There is something beyond the usual here. Frankly I'm surprised this problem has only come up with one other person on this site thus far. I could have written Frauleins message! NogBoy
 
I wonder if the focus screen is properly seated? With a manual focus lens what you see on the focus screen should be exactly what you get on the sensor unless something is mis-aligned, either the mirror or the focus screen. I have had this problem with film cameras before.

Even if the viewfinder dioptre setting is off it shouldn't affect anything. Its only function is to give you a clear view of the focus screen.

--
Steve

http://www.pbase.com/steephill
 
Yeh, focus screen seems the most likely culprit re a physical problem. When I sent CR kennedy some images they seemed to warm to looking at the camera pretty quickly... which I will do at some point... which indicates that they may be thinking along similar lines. After having a Pentax close at hand for 40 years its a bugger to have to do without it for a couple of weeks tho. The interesting thing is that the 17-70 and other modern lenses seem to be OK... as far as I can tell. Any views on that? NogBoy
 
AF lenses don't use the focus screen at all, see the diagram here http://kmp.bdimitrov.de/technology/AF/index.html The main mirror is semi-transparent in the centre and a portion of the light is directed to the AF cells at the bottom of the mirror box by a secondary mirror which is pivoted below the main mirror.

Manual focus lenses depend on the focus screen and if the result does not match what we see on the focus screen it is likely that the screen is out of position, especially if the AF system is working OK as this would imply that the mirrors are in the correct position.

I haven't ever removed my screen so don't know the answer, but I wonder if it is possible that the focus screen could have been inserted the wrong way round at the factory? I don't know how symmetrical the screen design is but it wouldn't take much of a difference in position to get a false focus. It seems to be easy enough to remove and replace a screen and it might be worth doing so just for piece of mind that it is in the right way round and secure.

--
Steve

http://www.pbase.com/steephill
 
I had difficulties focusing with my k100d. I was the told that due to the smaller viewfinder, actual dof would not be shown for less than f4.

(if you use an f1.4 lens, what you see in the viewfinder would actually be the dof of f4)

I confirmed this in testing. I have now gotten used to it, and are able to focus on smaller f-stops as well.

Ludvik
 
Steephill, that seems a perfectly reasonable possibility. I was not aware of the different focussing processes going on with older lenses. Not sure if you were suggesting I adjust the camera myself or not? But anyway, I think I'll opt for sending it off while its still under warranty... at some point anyway -
unless of course you're suggesting its an easy thing to do?
Personally I prefer to get a sharp image by eye rather than rely on the focus

indicator for most of my picture taking... unless on AF. Probably used to the old fashioned way of doing things I guess. But I noticed that the focus indicator was not any better at getting a decent image with my old lenses.

I my gut tells me its a physical problem somehow... so I think you're probably on the money. Thanks. NogBoy
 
Ludvik, Hmmm...possible I suppose. But why does my 50mm 1.4 look like its actually stopping down in the usual increments when I manually adjust thru from F1.4 to F16? That is, I can see the viewfinder darken (and the DOF change) as I adjust the aperture down. NogBoy
 
I have no problem about focusing with my SMC M 50mm 1:1.4 Did u set the K10D menu by going to Custom Setting go to Using Aperture Ring then select permitted press ok. u can read more details in using manual focus and aperture of old smc lens at
goodluck
 
ok here's the details:This is what I did....

I am going to assume you don't know how to use a fully manual lens with the K10D?

You put the K10 in manual focus, manual exposure. when you focus on the subject, the first thing you will see/ hear is the red beep. This means you are getting close to focus. When you are right on focus, the green light will appear in the center of your view finder... that is right on the money.
Now for manual exposure....

Set the apeture that you want on the apeture ring. In this shot since it was low light I had the lens set at between 2-2.8. Two stops from wide open is generally what you want to shoot for if light permits as at wide open most lenses are a bit soft. This will still give plenty of blur to the background if you wish. (of course depending on how far away you are from the subject)

After focus, point the center of the lens on the part of the subject you want to be in proper exposure, then push the little green button near the shutter. This will automatically sellect the proper shutter speed. Make sure it is not too slow, I think this one was between 1/30-1/50 second.

If you want to get creative and under and over expose, then this is how you do it....

Make sure that the preview in the K10 is set to optical, not digital. Point to where you want proper exposure, and push the shutter button half way down. With that held 1/2 way down, push the lever near the shutter button over to preview (opposite to off).Keep this pushed over.
Now look at the LCD near the shutter button.

It will have a the same type of line that there is on televisions to get the proper tint. Now one of the wheels (I don't have the K10 here at work but I think it is the front one) get the indicator to go to the middle. This is "proper" exposure. Any line before and after the middle is under/over exposure.

I use proper exposure as a loose term because it is a matter of taste, and since a camera uses reflective light, it isn't always accurate (like in scenes with snow, etc)

Hope this helps,
 
Your post maybe directed to Frauleins inquiry, but I too have had focus (and metering) issues in relation to old prime lenses. You will notice some of my posts on this thread.

Your directions re focussing and metering are correct of course, but my (our?) problem seems way beyond the basics in relation to this particular problem. I know that F1.4 can result in images that are not super sharp - re the edge effect - but I seem to be getting soft images above and beyond that.

The image in the viewfinder can be in absolute tack focus but subsequent pics can be quite out of focus. (I used a manually focussing SpII for 30 years and I think I've got the hang of it... for most of images at least!) My DS2 didnt seem to have this problem. With the K10 almost all the images are

soft. My older DS2 images are just fine. I think Steephill may be right and that it might be just be a focus screen issue. Either that or I've become totally incompetent and its time to take up knitting! NogBoy
 
Hi!

If what you say is true, I am wrong :)

I have experience with the k100d, and for sure i can´t see dof change significantly before about f4, when using dof-preview. I know the k10d has a bett viewfinder, but I am a bit surprised that you see a difference between f1,4 and f2 in dof....

Ludvik
NogBoy said:
Ludvik, Hmmm...possible I suppose. But why does my 50mm 1.4 look
like its actually stopping down in the usual increments when I
manually adjust thru from F1.4 to F16? That is, I can see the
viewfinder darken (and the DOF change) as I adjust the aperture
down. NogBoy
Click to expand...
 
One problem is that you just cannot accurately focus manually with the K10 screen.

When you have an f1.4 lens the DoF is very slim. I doubt that you can focus that correctly.

But just in case you could ...

If you have optimally focussed using the screen, but the resulting image then is out of focus, and on the other hand autofocussed images are ok, then the error MUST be in the optical path to the view finder.
It could be a misaligned mirror, or screen, or prism etc.
 
Going on from what Shane is eluding to are you setting SR to actual lens focal length when asked eg a %0 mm lens must be set to 50 not 75.
--
Regards Dean - Capturing Creation
 
Manual focus with modern DSLR's is pretty well impossible without some kind of focusing aid. The screens are almost clear and determining focus is pretty much impossible, at least for me.
--
Dave Lewis
 
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