Custom Function CF4-1

[AXENA]

I know that there is a huge thread on this topic, however, as a new 20D owner/user, I have to say that by using this function, the amount of "keeper" shots has increased dramatically, eliminated the under/overexposure issue, keeps the focus sharp and allows for recomposition very easily. Granted, I haven't shot at the racetrack yet, however, if using the "*" button to focus in AIServo mode is as accurate as the one-shot mode that I generally use, then, I am a CF4 convert for life!

Try it... you'll love it!

Good luck.....
Gary Latimer

[Dante King]

I too am a recient convert...could not imagine life w/o this set up.

[pierrot]

... and a couple of full charged spare batteries in your bag, too! :mrgreen:

[rg-tom]

for racing i think 4.3 is better as it re-evaluates the exposure constantly, so if you're tracking a car and it goes into shade itll fix it :D

[RDKirk]

for racing i think 4.3 is better as it re-evaluates the exposure constantly, so if you're tracking a car and it goes into shade itll fix it :D

The main problem there is that if you're not in evaluative mode, it will react to the changing brightness of the background, too.

[kawter2]

4-1 ALL the way!! can't imagine shooting any priority with partial metering w/o it

[BrianEE93]

Can you give some subject examples and techniques for this mode. I am trying to picture it in my jumbled mind and can see where it would be good for moving subject but my not just use AI Servo?

Thanks,

Brian

[pwaite]

Ok Folks just for a real Canon newbie what is C4.1 It sounds as though we cant live without it

[peter/c]

Ok Folks just for a real Canon newbie what is C4.1 It sounds as though we cant live without it
As I understand it, this sets up the camera so that the ' * ' button both sets the focus and exposure, in One operation, The shutter release button then just fires the shutter. The thought occurred to me, 'What if I want to meter for one part of a scene and focus somewhere else?' Maybe I have something wrong here, but personally I can't see much advantage.
Peter.

[ScottE]

Custom Function 4 determins the use of the * (AE lock) button on the back of the camera. It has had a similar funtion on many EOS cameras such as my EOS 3 film camera and my 20D. On the D60 it was CF 2.

CF 4-1 disables autofocus from the shutter button and assigns it to the * button. Auto exposure lock remains on the * button. That means the camera will focus when the * button is pressed, not when the shutter button is pressed half way. Auto exposure is set when the * button was pressed and does not change when the shutter is released.

CF 4-3 has a similar function except that auto exposure is adjusted again when the shutter button is pressed.

I usually set up my camera on CF 4-1 or 3, AI Servo auto-focus, auto-focus set for the centre senson only and use a Canon USM or Sigma HSM lens that allows full time manual override.

If I am shooting wildlife, I put the centre sensor on the eye of the animal, push the * button to focus, recompose the shot and then press the shutter button. I don't have to worry about holding the shutter button half way down as I would if using One Shot auto-focus.

If the animal starts to move, I can hold the * button down and get predictive auto focus to track focus as the animal moves. This is a lot faster than fooling with the camera setting to change from One Shot to AI Servo settings.

If I have the camera set on a tripod and want to change focus a bit without recomposing I can simply focus manually and not have to worry about keeping the shutter button pressed half way to keep auto-focus from kicking in.

You effectively have an instant choice between one shot, predictive or manual focus without making any changes to the camera.

Don't try try the manual focus if you use Tamron or Tokina lenses or some Canon and Sigma lenses that do not offer full time manual override. (This is the main reason I do not have any Tamron or Tokina lenses in my bag and find that many Sigma lenses are deficient. Most Canon lenses are good, but there are a few bad ones.)

Scott

[ScottE]

'What if I want to meter for one part of a scene and focus somewhere else?'
Peter.

That is why I use manual exposure in tricky lighting situations. I find that much more reliable than using the AE lock function on the camera.

Scott

[AngelaS]

LOVE this method of focusing!!!!

[Hydro]

OK, I will get over my newbie embarassement to ask the question, although I was hoping someone else would ask first.

What does "recompose" the shot refer to? Final exposure setting? I'm confused after reading all the CF4-1 threads, because folks talk about focusing in on a subject, then "recomposing" the shot.

The other thing I don't quite get on the CF4-1 setting is whether it is most useful using other than manual settings. I have been using manual since my first basketball outing with the 20D and AV wasn't working for me right-------plus I wanted to go fast track on learning how ISO, aperture, and shutter speed worked together on a shot anyway. As a result, I am not really familiar with the other semi-auto zones like AV and TV.

I can see the definite advantage of CF4-1 if you are tracking the action with the * button mashed, then letting the camera lock the exposure to reflect the actual conditions when the shutter is finally pressed. But if you are shooting in manual, what do you do? Use your forefinger to roll the shutter speed control (for example) to keep the exposure right (if things change) while the * button is pressed and you are tracking the players.

Seems like it would take some practice, but I just want to make sure I'm practicing the right thing. I would hate to become proficient at doing something wrong. Again.

Any help appreciated.

[tim]

Recompose means change what you see in the viewfinder. You focus on what you're interested, usually with the centre focus point, then move the camera a bit so it's still in the frame but not in the centre. You have to be careful when you're using wide apertures since the recompose can throw off the focus. Another idea, one I usually use esp with wide apertures, is to use an alternate focus point.

[SkipD]

CF 4-1 disables autofocus from the shutter button and assigns it to the * button. Auto exposure lock remains on the * button. That means the camera will focus when the * button is pressed, not when the shutter button is pressed half way. Auto exposure is set when the * button was pressed and does not change when the shutter is released.Scott, I just tested my 20D with CF4=1. Focus is, in fact, set and locked by pressing the * button, but the exposure is not set at all with the * button.

Exposure is locked by a half-press on the shutter button. With the shutter button partially depressed and the let up, the exposure tracks what you're aiming at for a while and you can re-lock exposure by holding a half-press.

[HJMinard]

I agree with Skip ... with CF4=1 the * button has absolutely nothing to do with exposure. It's easy to confirm ... when I half press my shutter button the * (exposure lock) symbol appears in the viewfinder. Change the setting to CF4=3 and the * symbol no longer appears with the half shutter press.

[Carzee]

Bookmarking this thread. Here is the reference on CFn4-1
(quote from 10D manual):

C.Fn-04--------Shutter button/AE lock button

0: AF/AE lock

1: AE lock/AF----------convenient when you want AF and AE lock to operate separately. Pressing the <*> button focuses on the subject, while pressing the shutter button halfway sets the AE lock.

2: AF/AF lock, no AE lock--------in the AI Servo AF mode, you can press the <*> button to stop the AF operation momentarily when there is an obstruction passing in front of the camera. This prevents the AF from being thrown off. The exposure is set when the shot is taken.

3: AE/AF, no AE lock------this useful for a subject that moves and stops repeatedly. In the AI Servo AF mode, you can press the <*> button to start or stop the AI Servo AF operation. The exposure is set when the shot is taken. Thus, the optimum focusing and exposure are always ready for the decisive moment.

[Hydro]

Thanks for that, Tim. Any thoughts on shooting manual with the CF4-1 anyone? I've seen others ask this question, but never seen it answered directly. Maybe it's a dumb question.

[markubig]

Scott, I just tested my 20D with CF4=1. Focus is, in fact, set and locked by pressing the * button, but the exposure is not set at all with the * button.

Exposure is locked by a half-press on the shutter button. With the shutter button partially depressed and the let up, the exposure tracks what you're aiming at for a while and you can re-lock exposure by holding a half-press. Yep, Skip is right. The purpose of this function is to separate the AF from the exposure. I can AF on my subject with the * button, expose for another area in the field of view with the shutter button half-pressed and then recompose to release the shutter fully. Really awesome once you get the hang of it.

[jobber73]

Recent convert here too. :)

I find 4.3 more useful for what I shoot, but have used 4.1 quite a bit as well.

I do find myself with more keepers, but the missed shots seem to be farther off than just using the shutter button to lock both focus and exposure. In other words there are less 'salvageable' shots.

But in the end the increased number of keeps makes it more than worth it. :)

[AXENA]

Hydro.... that is ALL I shoot with (now): CF4-1 and Manual. Once you get into the thought process of "Thumb for focus" "Finger for exposure" it really does become second nature, and everyone on the forum is correct; more keepers, better control of focus, easier to recompose without throwing off exposure/focus.... It really is a great way to shoot. I've only done it a few days since reading it here, and I have to say that the people on this forum know what they speak of... this is probably one of the best pieces of advice so far that I've seen. It's not rocket science and it really will (in the end) be a better way for you to shoot. But everyone needs to form their own opinions, so give it a try and see what you think! :-)

[Hydro]

Thanks much, Gary. I played around with it yesterday and did not find it uncomfortable at all. I see the advantage, and am looking forward to getting used to it at this weekend's games. Thanks to all for the input.

[BottomBracket]

Another CF4.1 fan here! It gives you plenty of control without going fully manual.

[sando]

Aaaaah... I get it now. This 4-1 thing just clicked. :)

[door]

Looks like I'm the only daft one here. Seems to me that all you're doing is swapping the roles of the shutter and'*' buttons.

Default setting:
1. Find area you want to meter off, press '*' to lock exposure
2. Find point you want to focus on, half press shutter button to hold focus
3. Recompose
4. Fully press shutter button to expose

Custom Function 1:
1. Find point you want to focus on, press '*' to hold focus
2. Find area you want to meter off. half press shutter button to lock exposure
3. Recompose
4. Fully press shutter button to expose

Is it simply a case of fixing focus before exposure?
If the focus point and area of metering are the same then what's the difference? Would this involve pressing 2 buttons with CF1 (* then shutter) as opposed to one button with default setting (shutter button)?

[René Damkot]

With CFn4 it's possible to make an exposure without (re)focussing. Nice to have if your subject is stationary, but AF not possible all the time (for instance a drummer in a band; smoke goes on, AF goes crazy)
With CFn4 you can use AI Servo and when you release the * button, focussing stops
With CFn4 you can work around the simultanious locking of AF and AE when using One-shot AF and Evaluative metering.
I'm sure I'm forgetting things.
Only drawback on any camera but the 10D or 1D (which have a dedicated button): You loose FEL.

[peatoire]

I've been using it for ages now, the only bugbear is if you are trusting enough to hand the camera over to someone to take a shot, you think 'now, shall I bother to try and explain the focus/shutter or just change back to CFn4-0 and then forget I've changed it :-)

[rabidcow]

That is why I use manual exposure in tricky lighting situations. I find that much more reliable than using the AE lock function on the camera.

Scott

Absolutly. I rarely allow my camera the authority to determine the proper exposure for me, as it is always wrong.

[dave_bass5]

Looks like I'm the only daft one here. Seems to me that all you're doing is swapping the roles of the shutter and'*' buttons.

Default setting:
1. Find area you want to meter off, press '*' to lock exposure
2. Find point you want to focus on, half press shutter button to hold focus
3. Recompose
4. Fully press shutter button to expose

Custom Function 1:
1. Find point you want to focus on, press '*' to hold focus
2. Find area you want to meter off. half press shutter button to lock exposure
3. Recompose
4. Fully press shutter button to expose

Is it simply a case of fixing focus before exposure?
If the focus point and area of metering are the same then what's the difference? Would this involve pressing 2 buttons with CF1 (* then shutter) as opposed to one button with default setting (shutter button)?

I thought that as well but once i tried it under certain circumstances it works really well.
I find the one BIG advantage is that you can take your figers off the buttons once focused and when you go to shoot the camera doesnt try and focus again. For example if you focus and re compose but you let go of the shutter button the camera will try and focus again without C-4-1 on when you take the shot.
I do find it awkward to use the * button though. it just doesnt feel right to me but i dont use C-4-1 long enough to get used to it.

[RTMiller]

I've been using it for ages now, the only bugbear is if you are trusting enough to hand the camera over to someone to take a shot, you think 'now, shall I bother to try and explain the focus/shutter or just change back to CFn4-0 and then forget I've changed it :-)
Just switch to that lonely little green box and you don't have to explain anything.;)

[malla1962]

4-1 is the first thing I set when I got my 1d.:D

[evandavies]

I'm just gona say that its great once you get used to it.

To clear up the difference between CFn4.1 and CFn4.3

Camera set to AI Servo and burst mode.

With CFn4 set to 1 the camera will lock exposure when the shutter is half pressed and will keep that exposure for the duration of the burst when fully pressed.

With Cfn4 set to 3 the exposure will continually evaluate even when the shutter is held at half press. So each shot would be metered in a burst. I think the burst rate is slightly slower due to the metering but not sure about that.

[malla1962]

I'm just gona say that its great once you get used to it.

To clear up the difference between CFn4.1 and CFn4.3

Camera set to AI Servo and burst mode.

With CFn4 set to 1 the camera will lock exposure when the shutter is half pressed and will keep that exposure for the duration of the burst when fully pressed.

With Cfn4 set to 3 the exposure will continually evaluate even when the shutter is held at half press. So each shot would be metered in a burst. I think the burst rate is slightly slower due to the metering but not sure about that.Thats interesting,never tried 4-3,may give it a go.

[superdiver]

WOW...all interesting stuff. I tried CF4-1 a while back and it just didnt feel right and I didnt want to get used to it, so I still use the CF4-3...