I might have messed up a CF setting on my 1DMk3?

I had played around with the CF settings on my Canon 1DMk3 a few days ago... trying some other togs settings I found in the official MK3 thread.

Subsequently (though only a few days later having taken some shots in between times), I noticed that my lenses refused to autofocus from a near to far subject or vice-versa?

For example I first noticed that the 100-400 just wouldn't achieve focus until I helped it manually to get into the zone, the it snapped in just fine.

I then noticed the same thing today with the 100 macro.

Neither of these lenses were close focus limited at the time...once I helped it get some way towards in focus they both snapped in.

This must be something I messed with on the body, well at least I hope it is.

Any pointers would be appreciated...
Jamie

ps meanwhile back to the manual...duh!
J

Just reset your all of your custom functions and start over. Taking custom functions from another photographer isnt going to make you any better. In this case, it has actually made you worse. Reset them all and make them work for you.

If you have record of your CF's before you started playing around that is good. I use a spreadsheet to record mine for different events as a backup. You can backup your basic and event seeting to a CF card for easy download. There are some spreadsheets available from this forum that give settings as an Excel spreadsheet that you can amend and add your own.

Bottom line you will want to follow Adam's recommendation to go to your Custom Function menu and do a "Clear all Custom Func." (C.Fn). This should get you back to square one and can start over. I do also wonder if your lens are Canon brand. There could be a setting that isn't getting along with your len(s).

Maybe CFnIII-5. If the camera thinks that AF is impossible, it wont hunt for focus.

I'm not sure if this is the same/correct custom function but the same happens as you described on my 40D wich the custom function, I'm pretty sure this is the custom function you have changed... "lens drive when AF impossible" If you set this to "focus search off" it wont focus if it is going to go from - for example infinity to 5 feet, it just won't focus. Set this back to focus search on - I have found some people use this, if they are tracking birds in flight, and it stops the camera from suddenly jumping from the bird, to the background.

AdamLewis wrote in post #6163441
Maybe CFnIII-5. If the camera thinks that AF is impossible, it wont hunt for focus.

Yep that looks like the one Adam thanks!

Bit harsh/judgemental I thought Adam. I chose the settings based on what I thought would work for me.

I did refer to the instruction manual first before making any CF setting and also before asking here, however, I might add that when the problem arose, there was absolutely NO hunting at all, they just would not focus i.e. the lenses did not move one iota from the OOF position with this setting, in other words with this setting, the camera did not even try to achieve focus at all! Let alone hunt. Hence my post.

There's little point in fellow forum members listing what works best for them if we only ever do our own thing IMO (my interest was best settings for BIFs). However I didn't think I needed to explain that.

Jamie

WAF wrote in post #6163404
If you have record of your CF's before you started playing around that is good. I use a spreadsheet to record mine for different events as a backup. You can backup your basic and event seeting to a CF card for easy download. There are some spreadsheets available from this forum that give settings as an Excel spreadsheet that you can amend and add your own.

Bottom line you will want to follow Adam's recommendation to go to your Custom Function menu and do a "Clear all Custom Func." (C.Fn). This should get you back to square one and can start over. I do also wonder if your lens are Canon brand. There could be a setting that isn't getting along with your len(s).

Thanks Adrian, yes I already took a backup of my CF settings to the card/pc and clearly no probs restoring same.

If you see my reply to Adam, I point out that CF III-5 in the manual doesn't describe what actually happens in my case.

Thanks for your help.

Jamie

Naturalworldphotograph​er wrote in post #6163456
I'm not sure if this is the same/correct custom function but the same happens as you described on my 40D wich the custom function, I'm pretty sure this is the custom function you have changed... "lens drive when AF impossible" If you set this to "focus search off" it wont focus if it is going to go from - for example infinity to 5 feet, it just won't focus. Set this back to focus search on - I have found some people use this, if they are tracking birds in flight, and it stops the camera from suddenly jumping from the bird, to the background.

Hit nail right on the head Ashley and your explanation is exactly why I was trying this setting (BIFs).

This surprised me. I somehow thought it would kick in only when it started to hunt clearly not and you are absolutly right - it just won't focus!

Many thanks

Jamie

WAF wrote in post #6163404
If you have record of your CF's before you started playing around that is good. I use a spreadsheet to record mine for different events as a backup. You can backup your basic and event seeting to a CF card for easy download. There are some spreadsheets available from this forum that give settings as an Excel spreadsheet that you can amend and add your own.

Bottom line you will want to follow Adam's recommendation to go to your Custom Function menu and do a "Clear all Custom Func." (C.Fn). This should get you back to square one and can start over. I do also wonder if your lens are Canon brand. There could be a setting that isn't getting along with your len(s).

Adrian, Thanks I've updated my sig. accordingly

Jamie

shoshone wrote in post #6166740
Thanks Adrian, yes I already took a backup of my CF settings to the card/pc and clearly no probs restoring same.

If you see my reply to Adam, I point out that CF III-5 in the manual doesn't describe what actually happens in my case.

In simple terms the AF is either

"I've got a good idea how to focus, I'll turn the lens to that point"

or

"Not a clue, I'll just turn the focus ring until something looks likely"

The Cfn stops the second option which means don't try to focus if you don't have a good idea, exactly the behaviour you experienced.

pxl8 wrote in post #6166768
In simple terms the AF is either

"I've got a good idea how to focus, I'll turn the lens to that point"

or

"Not a clue, I'll just turn the focus ring until something looks likely"

The Cfn stops the second option which means don't try to focus if you don't have a good idea, exactly the behaviour you experienced.

pxl8, Many thanks....CF III-5 is now off.

Jamie