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Old Mar 20, 2006, 11:09 AM   #31
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Jim,

Subsequent toour previousfront-focus"exploits" (discussed in the previous thread), I purchased a Minolta AF 50mm f1.7 lens, and used it for the focus test with the angled ruler.

That 50 is everything you said it would be: cheap, bright, and excellent.

Thanks,

Scott
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Old Mar 20, 2006, 11:21 AM   #32
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Good, I wanted to make sure you were not trying to tell from the zooms again (leaving doubt as to whether the body or lenses are the culprit).

Lenses do tend to have some variation, and sometimes even the aperture change from wide open (where a lens will be when the camera is focusing) and closed down (to the aperture you're shooting at) can impact focus accuracy.

You'll also tend to see some variation in AF accuracy depending on the subject distance and focal length used with some zoom lenses. Ideally, they're all be perfect at any aperture, subject distance or focal length. But, Autofocus is rarely 100% accurate with all lenses in all conditions.

For camera body tests, a simple "normal" focal length prime is usually best to test with (which is probably why KM uses a 50mm for AF calibration).

If it's front focusing with the 50mm, then it's probably out of alignment.

Personally, I prefer the simpler AF tests versus the rulers. So, I just use some very closely spaced books to verify mine.

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Old Mar 20, 2006, 11:43 AM   #33
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bernabeu wrote:
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Magnum,

the DOF is irrelevant

the actual focus point of the camera should precisely correspont to the aimed focus point

eg. if the center (AF) spot was on the 18" mark -> the 18" mark should be razor sharp (the 50mm f1.7 is used by KM to calibrate)

if it does not, send the camera to KM for calibration

i had my 7D for 11 months with not quite perfect results until i tested it myself and sent it in for calibration -> now get razor sharp images straight from camera

...john

ps. focus was on bird's eye
John,

Thanks for the clarity -- your reply makes the matter easy to understand. Hopefully, KM is still servicing and there won't be any transition"issues" with the camera needing to go to Sony.

Scott
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Old Mar 20, 2006, 12:04 PM   #34
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Magnum wrote:
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Hopefully, KM is still servicing and there won't be any transition"issues" with the camera needing to go to Sony.
Scott:

You'll want to wait for the transition to complete.

I've already seen two posters elsewhere say that KM sent cameras back unrepaired within the past few days because they won't have time to get to them before the transition is complete.

Sony should let us know where to send cameras, etc., within the next couple of weeks.

If it were mine, I'd just calibrate it myself (there are 3 hex screws under the metal plate with Konica Minolta on it by the tripod mount on a 5D, and you can pry the plate loose if you're careful). These 3 screws control the AF sensor alignment.

Adjusting all 3 screws counter clockwise should correct a front focus problem (probably by a *very* tiny amount as the adjustments are very sensitive with even severe AF calibration problems usually taking only around 1/4 turn). You'd need to use a tripod and adjust the screws until the target is sharp with the appropriate amount of blur in front of and behind your target.

You'd need to check with all AF sensors to make sure you didn't have a tilted sensor causing it (which is probably why there are 3 screws to allow for it). But, most people that have adjusted their KM models indicate that all 3 screws required the same amount of adjustment, keeping the AF sensor assembly level.

But, you'd risk damaging the camera and I don't know how Sony would handle it if they suspected you did it yourself. You're better off waiting until Sony clarifies how they'll handle warranty/service issues and let them adjust it..

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Old Mar 20, 2006, 12:32 PM   #35
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JimC wrote:
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You'll want to wait for the transition to complete.

I've already seen two posters elsewhere say that KM sent cameras back unrepaired within the past few days because they won't have time to get to them before the transition is complete.

Jim,

Thanks for the alert. I'm interested in tackling the adjustment myself. I will give some thought to the matterthis evening.

Scott
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Old Mar 28, 2006, 1:08 AM   #36
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JimC wrote:
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I've already seen two posters elsewhere say that KM sent cameras back unrepaired within the past few days because they won't have time to get to them before the transition is complete.

Sony should let us know where to send cameras, etc., within the next couple of weeks.
KM advises to call after April 1 and they will have instructions for sending cameras to Sony. Since I have realised that the focus can be out in several directions, the reason for 3 screws, it would take a few hours to setup a test, adjust, and recheck. My schedule is so jammed recently, I might have wait and have Sony do it.
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Old Mar 28, 2006, 6:30 AM   #37
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HAving had my 5D a feww weeks I had the same thoughts about sharpnes so I'm gladmy mind has been put at rest as the initial point about viewing large images on screen makes sense. When I print them out (CAnon ip4000) on 6"x4" glossy paper, they look much better.

Here's a picture taken (all auto settings and standard kit lens) at the weekend (not my bike!) and reduced in file size.


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