7D Mark II - Focus Discussions

The real issue is why was it out of spec. there was nothing to do to the camera but repair the rear wheel. this we will never know

Pondrader wrote in post #17828579
The real issue is why was it out of spec. there was nothing to do to the camera but repair the rear wheel. this we will never know

It very well may be but you really don't know that. What is spec? It is not a single number. As long is it is within upper and lower limits from perfect zero according Canon's specifications it is in spec. We could put 100 factory calibrated 7D's on a table in front if us and every one will vary slightly from the other. No two will be exact. it may not be noticeable in many areas but it is there. That is the world we live in.

When I sent my 7D2 in a few months they did a bunch of stuff like adjusting exposure I never asked for. After a year and a repair they probably include a basic service. I'm not saying it is right or wrong. Unless you were sitting beside the tech to see what happened you really don't know.

I rapped mine in a full page letter asking nothing be done but the wheel and later rapped in a letter asking that it be left at 1.0.4 and none of this was cared about. what I wished with my camera was not given a second thought.

Truth is I'm kinda done with the turmoil of repair of a simple wheel.

Agreed, and the lenses also have tolerances. The final result is dependent on the camera and lens tolerances together. Some combinations zero each other out and you get perfect results. Others are off slightly, and some may be completely out of whack once you add all this together. I have purchased entirely too much equipment over the years (just click the link in my signature if you want to laugh at me), and I have seen all different types of results due to these various tolerances coming together as I shoot.

It makes no sense to adjust on a camera that has no problem, what if I had payed to get it married with my 100-400LII

Sure, there is no reason to use MFA if you find no issues. The other settings though would always have to be looked at though to match the shooting scenarios.

I actually wrapped the camera in the letter and put it in the bubble rap it came in. then put an elastic around it

Pondrader wrote in post #17828649
I actually wrapped the camera in the letter and put it in the bubble rap it came in. then put an elastic around it

My guess is that they threw it out in the bin without even looking at it, thinking it was just packing paper

Twice

TeamSpeed wrote in post #17828629
Agreed, and the lenses also have tolerances. The final result is dependent on the camera and lens tolerances together. Some combinations zero each other out and you get perfect results. Others are off slightly, and some may be completely out of whack once you add all this together. I have purchased entirely too much equipment over the years (just click the link in my signature if you want to laugh at me), and I have seen all different types of results due to these various tolerances coming together as I shoot.

You don't know until you at least try and see what is going on. I see a big benefit with 3rd party lenses. I stick to Canon gear so I have the option of sending both lens and cam in together. I'm probably missing out. As much as I hate packing my gear I don't mind if I have to. I'm not going to do it for +5.

If it is a habit to throw out all wrapping that surrounds a camera body in order to put it into a work bin/work order, then it won't really matter how many times you send in a camera wrapped in a letter that you ask for something. When I have sent my cameras back in the past, even when dealing with an AF issue much like here, I sent a CD with images and notes, and a letter, all in a separate envelope inside the box with the camera. I think they looked at it all, the camera came back better (but not perfect). I also added as much to the repair request notes online as well, so that they had a record of it.

I rapped it in a neatly folded over the camera fashion then the bubble rap the camera came in from factory then wrote my name on the bubble rap in marker,..the camera always came back in the bubble rap with my name on it. but they did what they pleased

Anyway thats all water under the bridge, I'm hoping they send me a camera I can shoot over the holidays and full this server with in the years to come.

TeamSpeed wrote in post #17828449
... However, the area of most contrast is the snow on the rocks behind the critter, and that is where it to have taken the focus, at least from what I can see....

I believe the AF algorithm will pick the area with the greatest contrast, too. IE, the wet dark rock/snow interface. They might have placed some weight on the nearest subject, though. I'll have to test this.

Previous tests of mine seem to suggest that the AF pixels are similar in resolution to the image sensor in my 5D3. IE, saturated black lines that were one sensor pixel in width could be focused by the AF module.

With fur having regular, repeating patterns, the AF can be confused, and be off. The AF matches light/dark patterns from two opposing sides of the lens. Think of holding two hair combs together, and shifting one of them left/right, so you can see thru the open areas of the teeth. Many positions will align.

skid00skid00 wrote in post #17829002
I believe the AF algorithm will pick the area with the greatest contrast, too. IE, the wet dark rock/snow interface. They might have placed some weight on the nearest subject, though. I'll have to test this.

Previous tests of mine seem to suggest that the AF pixels are similar in resolution to the image sensor in my 5D3. IE, saturated black lines that were one sensor pixel in width could be focused by the AF module.

With fur having regular, repeating patterns, the AF can be confused, and be off. The AF matches light/dark patterns from two opposing sides of the lens. Think of holding two hair combs together, and shifting one of them left/right, so you can see thru the open areas of the teeth. Many positions will align.

What are we talking about, single, expansion or zone?