Selling EX3, back focus OK? need good opinions.

[Glynn Morgan]

So I sent my EX3 to a service centre a while ago for back focus issues, but since then I have had health problems and barely used my EX3. I have decided to sell it now, but I thought just to be sure, I better check the back focus seems in check, so its working as well as an EX3 does.

Here are some screens I took after I had my camera serviced last year, do these look normal? I would really appreciate some opinions.

This is f 4, Full tele, mid and full wide. The white balancing was sloppy so I grey scaled the images.

Cheers!

Should I recheck it again now? seeing as it hasn't been used in a while?

[Bruce Rawlings]

back focusl seems fine. Looking for an EX3 but shipping to the UK would be a little expensive I think.

[Glynn Morgan]

Oh dear, I just did a test then, having focused zoom in moving to 15mm goes soft and can actually be improved by refocusing using the peaking function. Having adjusted this at 15mm, full wide is not affected either way, only at mid zoom points does it appear soft.

I guess I can't sell it until I get this sorted at Sony, but they'll probably think I'm being pedantic. Thoughts?

[Roddy Jamieson]

Are you actually doing the auto back focus adjustment from the menu. Lock off about 10 feet from the chart and you are well lit but iris should be wide open. Make sure iris and focus are on auto and go.

15mm is a bit too close, in fact I would say far too close get any focus, unless your on macro. If you do the auto Back Focus all will be well.

With regard to Peaking, that does nothing to the recorded picture, it's only an adjustment for the viewfinder, makes it easier to judge focus by artificially sharpening the image. After all you would not adjust the viewfinder brightness if the picture appeared underexposed.

Regards

[Glynn Morgan]

"15mm is a bit too close, in fact I would say far too close get any focus"

No, Roddy I was zoomed at 15mm focal length (indicated on the zoom ring).

"With regard to Peaking, that does nothing to the recorded picture, it's only an adjustment for the viewfinder, makes it easier to judge focus by artificially sharpening the image."

Not what I meant, I used peaking to show me how sharp the image was (not 100% easy to tell on a viewfinder), I was able to use peaking to adjusted the focus ring so it was sharper and turned out the second image.

It's the same method many cameramen use if their back focus is out of whack, but they need to urgently shoot in focus, they use the peaking function to determine what is sharp and what is not. Thats how I knew it was getting soft when I zoomed out.

I'll take it to sony and get them to look at it, I just want to know if a bit of give in the focus at mid focal lengths is normal.

[Glynn Morgan]

I really do appreciate the opinions on these screens though.

[Roddy Jamieson]

Glynn, must be something getting lost in the Aussie / Scottish translation. I would say that the viewfinder with no peaking at all is way to soft to judge focus, so I always have a very small amount dialled in.

Good luck but sometimes the more you look the worse it becomes and it becomes a bit of an obsession.
It's happened to me.

Kind regards

[Chris Clifton]

They know EXACTLY what your problem is because they've seen it a hundred times, and I'm one of the hundred that went to the matt with them. Make them fix it. And if they can't fix it, make them replace the lens or the camera or both. They will.

[Ed Kukla]

Make sure you are doing back focus right for this camera.

If you have anything in the foreground or background, you can fool the electronic back focus. You need to actuate the electronic back focus when the camera can only see a flat wall at the wide angle lens setting.

[Glynn Morgan]

I really appreciate the replies. But this was the result of Sony's own back focus adjustment, I haven't needed to readjust myself because the lens hasn't been removed. So I have taken it in again for them to see how it goes soft mid zoom. I even gave them a CD with example screen shots. Its quite hard to find a completely flat wall large enough to light and fill the entire frame once its zoomed out from ten feet where I live.

If it comes back from the shop with the same issue as in the above screen shots, what should I do?

[Glynn Morgan]

Originally Posted by Roddy Jamieson

Glynn, must be something getting lost in the Aussie / Scottish translation. I would say that the viewfinder with no peaking at all is way to soft to judge focus, so I always have a very small amount dialled in.

I'll just clarify, I use peaking to set my focus every time when its 100% zoomed in. After doing this, I should be able to zoom out and see no change in sharpness. Unfortunately, mid zoom it goes soft, before going relatively sharp at wide.

So when halfway zoomed it is soft, so I then use peaking AGAIN to calibrate the focus, thus a sharper image then when I had purely relied on focusing at 100% zoom.

Hence why one image is soft (focusing at full tele) and one is sharp (using the peaking function soley to focus at that zoom distance, instead of relying on focusing fully zoomed in on the subject)

[Glynn Morgan]

The Sony Service people have decided to order a replacement Lens. Probably because I supplied a DVD with the high res versions of the screenshot examples above.

I'm pretty chuffed that they haven't taken me for a neurotic technological hypochondriac.