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07-04-2009, 07:35 AM   #1
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Unbale to get good pictures using 50mm 2.0f prime

Hi All,

I have a K100D Super and i have Sigma Zoom lenses ( 28-80mm and 70-300mm).

Recently i bought a Vivitar 50mm 2.0f K Mount lens and when i used it the photos i shot are so blurry ..I tried in Manual and Auto Focus settings..

I know with this lens doesn't support Auto Focus. I thought the prime lenses will produce more sharper pictures than the zoom lenses..

I am sure i am doing some thing wrong..Do i need to change the ISO Settings ??

I set the ISO Setting to 100. When i try to adjust the metering from 100-4000 in none of the settings i am seeing the green/red icon in the view finder.

Thanks
Mars..

07-04-2009, 07:50 AM   #2
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I'm not sure what your technical level is, but I'll assume you're a beginner and start from there. If the shots are blurry, it means either:

1- you are moving while you take your picture. That means you either are using a too low ISO value, or an aperture that is too small. If it's a manual lens, you probably have to set the aperture yourself by using the aperture ring. Set it to a small number, which means a large aperture. Go to manual mode, and use stop-down metering (the AE button on your camera if I'm not mistaken). What is the shutter speed currently selected by your camera?

2-you are not in focus. How do you proceed to focus manually? The best way is to half-press the shutter (with the focus mode set to MF), slowly turn the focus ring on your lens, and wait until you see the focus point light up red. That means the camera thinks you're in focus.

I hope it helps.
07-04-2009, 08:14 AM   #3
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Please post some pictures of what you are seeing. bdery has pretty much laid out what could be happening here. I have a A50 1:2 lens that is more than capable at delivering sharp images so as long as your lens is not faulty then I do not see why you wouldn't be able to do so with your setup as well.
07-04-2009, 09:49 AM   #4
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It's also possible he was shooting at f/2 and didn't realize how shallow the DOF would be - very little of a scene would normally be in focus at f/2. But yes, sample images, accompanied by info on what aperture and shutter speed were used, would help.

Also, was SR on? And did you set the focal length to 50 in the SR menu?

07-04-2009, 10:02 AM   #5
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Hi, welcome to the forum .

There has been a rash of postings lately regarding blurry/fuzzy pictures with vintage glass. As noted above, the first culprits to consider are camera motion and focusing issues. There are also a few other things to that relate to the lens itself.
  • Is the glass clean (both front and rear elements)?
  • Is there internal fungus or gunge or defects?
That second point is fairly important. One of the blurry image threads turned out to be caused by gross contamination inside the lens. With any used lens, it is important to evaluate the condition of the internal elements. Here is the technique:
  • Use a dimly lit room and a small flashlight (torch to some readers)
  • Look into the back of the lens while shining the flashlight at an oblique angle into the front of the lens
  • Move the light and your viewing angle around for a thorough inspection
  • Look for fungus (fuzzy or filamentous stuff), scratches, element separation (tree-like pattern or discontinuity), oil droplets, and gunge
  • Repeat using the front element
This technique will expose pretty much anything that might degrade the image. Be aware that issues with the rear element(s) are more critical than problems with the front. Even a small spot of fungus on the internal surface of the rear element will degrade performance at all apertures.

Steve
07-04-2009, 10:05 AM   #6
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Hi,

Thanks a lot for the feedback..

I have set the Mode to M, Tv and Av and took some more pictures and the picture are some what better..

Here are some pictures i have taken..

Pic 1:

Shutter Speed : 1/350Sec,
Capture Mode: Aperture Priority Automatic Exposure
Metering Mode : Center-weighted metering
Sensitivity : 200

Pic 2:

Shutter Speed : 1/45 Sec
Capture Mode: Aperture Priority Automatic Exposure
Sensitivity : 200


Thanks
Mars
Attached Images
   

Last edited by mars76; 07-04-2009 at 10:10 AM.
07-04-2009, 10:23 AM   #7
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Here are few more pictures i have taken using the Zoom Lenses..

1) 28-80mm

Focal Length : 45mm
Apertures : f4.5
Capture Mode : Auto Picture (Portrait)
Sensitivity : 200



2) 70-300mm

Focal Length : 70mm
Apertures : f4.0
Shutter Speed : 1/90 sec
Capture Mode : Auto Picture (Portrait)
Sensitivity : 200
Attached Images
   
07-04-2009, 10:38 AM   #8
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What were the aperture settings for the first two photos? The first one looks out of focus, easily done at the widest apertures as Marc suggests. The second photo seems like the same issue. The foreground is more in focus than the center of the photo. This leads me to believe that the camera was moving while the shutter closed. SR will only work laterally to compensate for movement in the up/down and left/right directions not in the forward/back directions.

07-04-2009, 11:09 AM   #9
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Hi,

I couldn't see any Aperture settings for the two photoes when i open them in Photo Browser..

It's showing F-,- !!
07-04-2009, 11:13 AM   #10
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QuoteOriginally posted by mars76 Quote
Hi,

I couldn't see any Aperture settings for the two photoes when i open them in Photo Browser..

It's showing F-,- !!

because you are using a manual lens. the camera cant control the aperture, it has no clue what the aperture is. you have to adjust the aperture manually. with the aperture ring (on the lens).
07-04-2009, 12:07 PM   #11
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And actually this sheds more light on your issue. If I am not mistaken, as I have not shot a fully manual lens on my K100DS for a while, the K100D will take the photo wide open when set to Av. In order for you to stop down the lens and meter correctly using the AE-L button you must be in manual mode.
07-04-2009, 12:24 PM   #12
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QuoteOriginally posted by MrApollinax Quote
And actually this sheds more light on your issue. If I am not mistaken, as I have not shot a fully manual lens on my K100DS for a while, the K100D will take the photo wide open when set to Av. In order for you to stop down the lens and meter correctly using the AE-L button you must be in manual mode.

correct. (I had to dust off a K mount lens to test) when using a manual (pre-A) K mount lens, it will only meter correctly using AV, wide open. when you mount the lens it will stay wide open, no matter what you change the aperture to. so unless you plan on only using the lens at f2, you will have to use M mode and do stop down metering with the AE-L button. with this method, you adjust the aperture to what you would like (you can check DOF by selecting 'optical' in the preview method section in the custom settings menu) then press the AE-L button. this will stop down the lens to the aperture you set (using the aperture ring) meter the light and then set an appropriate shutter speed. then you trip the shutter.

I am going to assume the K100DS' menu is the same as the K110D here.

in the 'custom setting' menu, make sure your settings are like this:

AE-L bttn on M expsr >2
FI with S lens used >2
Using aperture ring >2
Preview method >2
(this one is optional, but needed if you want to check DOF in the viewfinder)
07-04-2009, 12:35 PM   #13
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Your shots are not in focus, start there. And then understand that at large apertures like F2.0, depth of focus is very shallow. Try shooting at F4 or 5.6, then compare it to your zoom at the same aperture and focal length and you'll have an equal comparison. P.S. - it looks like you may have used the flash for your zoom shots, making for an unfair comparison.

Last edited by F16; 07-04-2009 at 12:48 PM.
07-04-2009, 01:34 PM   #14
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Hi séamuis,

Thanks for the info..I have changed the settings and now i see the green light in the View Finder and earlier when i was taking the pictures the shake reduction was always OFF. After changing the settings the Shake reduction is on and it allowed me select the lens focal length which is 50mm.

How ever when i opened the photos in Photo browser i still don't see the Aperture setting.. I took few pictures by settings different values in the Aperture ring on the lens and all the pics look almost the same and none have aperture value when opened in the Photo Browser.. I shot all these in Manual (M) mode..

Irrespective of the Aperture value i have set on the lens the shutter speed is always set to 1/60 sec.

Thanks so much for the info guys..I am learning some thing with each post :-)

Thanks
Mars
07-04-2009, 02:13 PM   #15
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QuoteOriginally posted by mars76 Quote

How ever when i opened the photos in Photo browser i still don't see the Aperture setting.. I took few pictures by settings different values in the Aperture ring on the lens and all the pics look almost the same and none have aperture value when opened in the Photo Browser.. I shot all these in Manual (M) mode..
You're not going to see the aperture value recorded anywhere in the photo file. The camera has no way of knowing what it is with that lens. There is no communication between the lens and the camera body.

QuoteOriginally posted by bdery Quote
2-you are not in focus. How do you proceed to focus manually? The best way is to half-press the shutter (with the focus mode set to MF), slowly turn the focus ring on your lens, and wait until you see the focus point light up red. That means the camera thinks you're in focus.
The red focus point lighting up is merely an indication of which focus point the camera is going to be using. It is not a focus confirmation.

There is a separate focus confirmation indicator. It is the green hexagon.
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