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11-17-2008, 04:08 PM   #1
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A friendly reminder about SR

Over the weekend I purchased a Vivitar 28.. f2.8 cf. I went out today and shot some test landscapes with my K10. As I was shooting I turned on the SR and noticed the image was very out of focus, to the degree of being unrecognizable. After several shots I couldnt figure out what was going on and then it hit me. I checked the focal length setting and it was still on 800mm from the last time I had used a manual lens. It never occured to me how much this would affect image quality. I realize going from 800mm to 28mm is extreme, but wow! So remember when switching manual lenses set the focal length for the SR! This would also make me think twice about a manual zoom like the Vivitar series one 80 - 210. As a side note I noticed even thought this is an A mount lens, Aperature data was only visible in the A setting. Manually changing the aperature ring required me to meter with the green button.

11-17-2008, 05:09 PM   #2
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QuoteOriginally posted by shuie Quote
Over the weekend I purchased a Vivitar 28.. f2.8 cf. I went out today and shot some test landscapes with my K10. As I was shooting I turned on the SR and noticed the image was very out of focus, to the degree of being unrecognizable. After several shots I couldnt figure out what was going on and then it hit me. I checked the focal length setting and it was still on 800mm from the last time I had used a manual lens. It never occured to me how much this would affect image quality. I realize going from 800mm to 28mm is extreme, but wow! So remember when switching manual lenses set the focal length for the SR! This would also make me think twice about a manual zoom like the Vivitar series one 80 - 210. As a side note I noticed even thought this is an A mount lens, Aperature data was only visible in the A setting. Manually changing the aperature ring required me to meter with the green button.
If you only attach your lens with the camera turned off, the SR focal length screen will appear automatically when you turn the camera on. I have this personal thing about changing things with electrical contacts with the power on.
11-18-2008, 08:04 AM   #3
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This is true, however it only stays available for a few seconds. In my case I didn't look at the camera back when swapping lenses. I think the big shock came when I realized just how much having the wrong focal length set degraded image quality.
11-18-2008, 08:15 AM   #4
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Makes the SR kinda useless for manual zooms.

11-18-2008, 08:18 AM   #5
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This is another good reason for checking for checking ALL the settings when we turn the camera on. I have had plenty of deletes because I had left the 2 sec timer setting on and took the camera out for a quick shot and did a WTF and got a picture of the sidewalk.
11-18-2008, 08:27 AM   #6
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Been there done that with the 2 sec timer. lots of pics of my feet over the years!
11-18-2008, 12:03 PM   #7
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QuoteOriginally posted by shuie Quote
This is true, however it only stays available for a few seconds. In my case I didn't look at the camera back when swapping lenses. I think the big shock came when I realized just how much having the wrong focal length set degraded image quality.
I always turn off the camera before changing lenses. I have trained myself to turn the camera on immediately after putting on one of my M lenses and select the proper focal length, or nearest available with an extender. Now I just press [OK] the next time I power up the camera, because the menu defaults to the focal length I have already entered.
11-18-2008, 12:41 PM   #8
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QuoteOriginally posted by shuie Quote
Ov As a side note I noticed even thought this is an A mount lens, Aperature data was only visible in the A setting. Manually changing the aperature ring required me to meter with the green button.
um, thats why you put it on "A" and use your edail to change aperture , thats the whole point....

11-18-2008, 12:52 PM   #9
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QuoteOriginally posted by anomaly Quote
Makes the SR kinda useless for manual zooms.
Not totally. My impression is that it is better to *understate* than *overstate* the focal length, and that overstating by a *little* won't hurt. So, with a 70-200 zoom, maybe call it 85 or 100, and you'll still be better off than you would with no SR.
11-18-2008, 01:27 PM   #10
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My comment about the "A" setting may be a little misleading. What I'm referring to is if you use the manual aperature ring on full service lenses, it automatically puts you in aperature priority mode if I remember correctly. Now when I manually set the aperature ring to a different aperature it only functioned in manual mode with no aperature data visible. Also pressing the shutter halfway did not meter at the restricted aperature. In essence it made me use the lens as an M lens. Not a big deal but did cause some bad exposures. I'm sure this is all normal. To be honest I usually use either M lenses or fully automatic lenses. This is one of my few "A" lenses and most of those I haven't used much. I will say for me often I use the aperature ring as opposed to the rear dial so as to prevent inadvertently changing aperature while shooting.
11-18-2008, 01:31 PM   #11
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QuoteOriginally posted by shuie Quote
My comment about the "A" setting may be a little misleading. What I'm referring to is if you use the manual aperature ring on full service lenses, it automatically puts you in aperature priority mode if I remember correctly. Now when I manually set the aperature ring to a different aperature it only functioned in manual mode with no aperature data visible. Also pressing the shutter halfway did not meter at the restricted aperature. In essence it made me use the lens as an M lens. Not a big deal but did cause some bad exposures. I'm sure this is all normal. To be honest I usually use either M lenses or fully automatic lenses. This is one of my few "A" lenses and most of those I haven't used much. I will say for me often I use the aperature ring as opposed to the rear dial so as to prevent inadvertently changing aperature while shooting.
well yes, this is exactly how it was designed, this is perfectly normal.

the ability to manually select the aperture is for backward compatability, something the DA lenses decided to abandon alltogether.

If your lens has the A setting, and your camera can use Av mode, there is absolutely no reason to use the aperture ring.

and you get bad exposures because the camera will think that your lens is always wide open.
11-18-2008, 02:07 PM   #12
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QuoteOriginally posted by anomaly Quote
Makes the SR kinda useless for manual zooms.
Nah, not really. I used to use it for manual zooms all the time. I just set it for the middle of the zoom range and snapped away. Someone figured out whether it was best to have it set closer to the wide end or the telephoto end, but I can't remember the results. I just know it worked okay for me the way it was.

I've gotten rid of all my manual focus zooms now, but never had a problem with SR on them.
11-18-2008, 02:52 PM   #13
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QuoteOriginally posted by Gooshin Quote
...
If your lens has the A setting, and your camera can use Av mode, there is absolutely no reason to use the aperture ring.
...
Here's a reason: So that the operation of the camera is the same with an "A" lens as with your other manual lenses...

here's another: because I like to.

now if you had said "If MY lens and camera...." then I wouldnt argue. But I think there are as many reasons as there are people...
11-18-2008, 03:27 PM   #14
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My camera does not always ask me about the lens focal when I turn it on. And I always switch lenses with power off. Did this once today actually, after switching from 105mm to 24mm. Whenever I catch this I just turn off and on again. But it's an odd glitch, even if rare.
11-18-2008, 03:33 PM   #15
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QuoteOriginally posted by kmccanta Quote
Here's a reason: So that the operation of the camera is the same with an "A" lens as with your other manual lenses...
so you want to do more work, go ahead

QuoteOriginally posted by kmccanta Quote
here's another: because I like to.
some people like to open beer bottles with their teeth, doesnt mean they should.
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