Finally, Back Button Focusing

[rpcrowe]

I have to admit, I have been amiss regarding back button focus. For some unknown reason I have been avoiding it even though I realized that this is probably a better way to shoot in many situations. This reminds me of shooting JPEG when I bought my first DSLR camera (Canon 10D). It wasn't until I was shooting digital for a while that I switched over to RAW. I had apprehensions but, I never regretted the switch from JPEG to RAW. In fact, I like RAW so much I open most JPEG images (which have been sent to me by our rescue volunteers) in Camera RAW...

I was perusing the Internet in response to the query about setting auto-focus points on Canon DSLR cameras and came upon this YouTube video by Amy Rizzuto. https://www.youtube.com/watch?v=B0c9PrYZe14

This four and a half minute video convinced me to try back button focusing and other YouTube videos brought me up to date on the back button process.

I love YouTube... It has some wonderful information; except that the video on "Self Apendectomy With A Rusty Can Opener" might be a bit far out Anyway, I am well on my way to using back button focus and should have been doing that since I acquired my 40D, quite a few years ago...

This page from the Canon Learning Center has more back button focus information:
http://www.learn.usa.canon.com/resou..._article.shtml

[PhotomanJohn]

Richard - I know how you feel about waiting to do something that turns out so worthwhile. IMO back button focus is the single best configuration change that I have made to the camera. No more fooling with the lens switch or the camera refocusing when you don't want it to. Another great feature is leaving the camera in continuous focus mode then you can instantly select single or continuous by whether you hold the button down momentarily or continuously.

Not sure about Canon but on Nikon one needs to also tell the camera to ignore whether it thinks it is properly focused or not before it operates the shutter. Otherwise it will prevent the shutter operation when you are trying to do something creative with the focus. Also Nikon has this feature in its continuous focus mode that will delay refocusing if the object is lost (went behind a tree?). Setting this delay to zero greatly improves the camera's ability to follow a moving object and still release the shutter when you want to.

John

[nimitzbenedicto]

Hi Richard,

Thanks for that

YouTube video by Amy Rizzuto. https://www.youtube.com/watch?v=B0c9PrYZe14

.
When I clicked on her video for Canon, I stumbled upon this video explaining how to use Nikon's "AF-On" back-button.

http://www.youtube.com/watch?v=WyPv1bLkwqA

I guess, just like you, will start using this back-button which I hardly used before.

Thanks

[Mike Buckley]

Once I discovered the usefulness of rear button focusing, I also never looked back. That's partly because I'm a klutz and had a difficult time holding the shutter release button half-way down without releasing the shutter. It's also partly because holding the back button down firmly helps me stabilize the camera.

My only regret when using the back button has to do with using image stabilization. When using a Nikon lens (I don't know about other manufacturers), that stabilization will not be used when using only the back button to focus. You also have to press the shutter release halfway, which my wife isn't comfortable doing. I don't own any image stabilization lenses, so it doesn't affect me unless I rent one and want to use that capability.

EDIT: Dave explains in a post below that the back button on his Nikon D7100 does indeed activate image stabilization (called Vibration Reduction by Nikon). Not true on my cameras, which are earlier models.

[DanK]

I've been using back button focusing on my 50D for years. It has lots of advantages, particularly for macro work. If you have lenses with full time manual focusing, you can go back and forth between manual focusing and AF instantly, without taking the time to fumble for the switch. If you use center-point AF and recompose, the shutter won't activate AF and throw your focusing off.

At least in the case of my 50D, Canon has neither of the issues noted above. The shutter trips whenever I tell it to, regardless of focus, and image stabilization is triggered by the back AF button. Also, both my wired and wireless remote shutter triggers work fine with the camera set to back-button AF.

It took me a few weeks to get used to it, and I actually took a few shots out of focus because I had forgotten about the change, but once I had gotten used to it, I never had any temptation to change back. I only change it back when I pass the camera to someone else to use.

[Harpo]

Ha. I was there! It took me a little while after reading about back button focusing before the light bulb went on and I got it! Now if that light bulb will come on a bit faster for some of the other things with the camera!

[PhotomanJohn]

My only regret when using the back button has to do with using image stabilization. When using a Nikon lens (I don't know about other manufacturers), that stabilization will not be used when using only the back button to focus. You also have to press the shutter release halfway, which my wife isn't comfortable doing.

Mike - You are correct that the stabilization does not come on during the AF operation but it is not a negative thing. VR/IS is not needed for auto focusing, only when the actual image is captured which is done when you press the shutter button. I'm not sure why it would be a benefit to have it operate when focusing. So the normal operation of actually taking the photo is to press the shutter button half way to get the VR/IS operating then pushing it the rest of the way to take the photo.

John

[rpcrowe]

Ha. I was there! It took me a little while after reading about back button focusing before the light bulb went on and I got it! Now if that light bulb will come on a bit faster for some of the other things with the camera!

Mike, speaking about "lightbulbs" I have only just upgraded to the newer 2.0.x, 7D firmware. When the firmware was introduced by Canon, I decided to wait a bit to see if It contained any inherrent flaws.

It didn't but, since I really did not need any of the new upgrades, I simply put off upgrading. I just did the upgrade a short while ago. However, since I don't use my 7D for video work, have never shot mor e than 15 images in a burst and don't use auto ISO, I don't think that the upgrade will impact my shootng...

[Adrian]

Yes! This cropped up recently in another thread and as a result I looked into back button focus. Very useful feature that I had ignored hitherto. I find when using my long telephoto that it is extremely helpful as either continuous focus or focus recomposition is very easy without necessarily firing the shutter.

[Dave Humphries]

Hi guys,

I'm another very recent convert.

I had read about it before, even tried it for a day (on my D5000), but didn't get the hang of it and gave up.

Recently I treated myself to a new camera; the D7100 and in "getting to know" that over 2-3 days of intensive shooting, I gave this a try again - I think I am getting there

I have made several other changes to my technique; shooting in better light, using a mono-pod, higher iso for higher shutter speed and using the 70-300mm lens' sweet spot of f/11 whenever possible - in addition to Back Button (thumb!) focusing.

My keeper rate has increased considerably; from taking 800 shots and having <100 technically OK ones, to easily 50%+ (400) good ones - well that's how it seems at the moment but perhaps I'm in the "honeymoon period" one gets with new kit

BTW-1, on the D7100, both AF-ON (actually the reprogrammed AE-L/AF-L button) or the shutter half press starts the VR, but since I'm often using it in continuous mode and for burst shooting, this doesn't matter to me.

BTW-2, I have my release mode set for Focus priority - I can't see the point in shooting something not in focus
I do still get some that aren' sharp, but this is usually where the subject moved their head/eye out of the focus point just as I was shooting - or I forgot to use my thumb

BTW-3, ironically, the AE-L/AF-L button on the D5000 is actually better placed than on the D7100, with the latter; I find my glasses can crash in to my thumb on the AE-L/AF-L button when peering through the viewfinder!

Primary benefit of AF-ON:

It is the instant ability to not have AF re-focus when I take a next shot (and I don't want it to) that I find most useful - no more fumbling for the switch on the lens to go manual and if I fine-tune the focus manually, it won't change that on the next shot. Furthermore, when I do want AF again, it is right there, under my thumb.

Cheers,

[Mike Buckley]

I'm not sure why it would be a benefit to have it operate when focusing.

It's not that it would be helpful to have it operating during that phase. Considering that it I haven't heard that it would be harmful to do it then, it would be helpful to have it operating before pressing the shutter release button so you wouldn't have to add an extra step of pressing it halfway before fulling pressing it.

[Mike Buckley]

on the D7100, both AF-ON (actually the reprogrammed AE-L/AF-L button) or the shutter half press starts the VR,

That must be a new development, Dave. The manuals for the D5100 and D7000 explicitly explain that the AF-ON button does not activate the Vibration Reduction.

but since I'm often using it in continuous mode and for burst shooting, this doesn't matter to me.

What am I missing? Why wouldn't Vibration Reduction be helpful in those situations?

I can't see the point in shooting something not in focus

You have never taken a photo of me.

[Dave Humphries]

That must be a new development, Dave. The manuals for the D5100 and D7000 explicitly explain that the AF-ON button does not activate the Vibration Reduction.

I agree - I haven't checked my manual, just saying how I noticed it working for me.

What am I missing? Why wouldn't Vibration Reduction be helpful in those situations?

I think it is - at least on long telephoto lenses, as it allows more accurate placement of, or tracking to keep, the focus point over the eye - the Nikon video guy said it not being triggered was good because it didn't use up battery life - while that is valid to an extent, I know what I'd rather have

You have never taken a photo of me.

True

[Mike Buckley]

I haven't checked my manual, just saying how I noticed it working for me.

Just out of curiosity, I did check your manual. After conducting a search of "vibration reduction" and "AF-ON," I have concluded that the manual doesn't address the capability. That's odd, to say the least.

[PhotomanJohn]

it would be helpful to have it operating before pressing the shutter release button so you wouldn't have to add an extra step of pressing it halfway before fulling pressing it.

Mike - Normally I am not holding the focus button in continuously so I still would have to wait for the VR/IF to come up to speed.

I think it is - at least on long telephoto lenses, as it allows more accurate placement of, or tracking to keep, the focus point over the eye - the Nikon video guy said it not being triggered was good because it didn't use up battery life - while that is valid to an extent, I know what I'd rather have

Dave - Something related to your comment is that while VR is on prior to the shot it reduces the camera movement you see in the viewfinder. When you press the shutter button, the position of the VR controlled optics are reset to their centered position then go back to stabilizing the image during the exposure. This is done so that the system has capability of full movement to stabilize the image during the exposure. You may have noticed that the image in the viewfinder is shifted when the mirror drops down again after the image is captured which is the result of this feature.

John

[rpcrowe]

My problem is that I am physically uncoordinated. I cannot walk and chew gum at the same time. I have trained myself over the years to use the shutter button pressed half-way to achieve focus.

OTOH... I have about ten days until my European trip starts and about three weeks until my Istanbul leg comes up...

BTW: Cross your fingers for me that the riots subside in Istanbul. I cetrainly do not want to walk into the midst of a civil disorder. I'd like to have a source for accurate information on those riots. I don't really trust the major news agencies in either the USA or UK for accurate and unbiased coverage...

[DanK]

Just confirmed. On my Canon (50D), with AF assigned to the back button, both the back button and the shutter button activate image stabilization.

[Ken MT]

If you use back button focusing do you also change the <AF-ON> and <*/Q buttons (C.Fn IV-2 1:enable, in the 5D MK2). This puts the back button to the middle (closer to the right hand) of the camera, and feels more comfortable to operate?

[Glenn NK]

Just confirmed. On my Canon (50D), with AF assigned to the back button, both the back button and the shutter button activate image stabilization.

Dan:

It's been that way for a while with Canon; my 30D operates this way. I can hear the IS working when I press the "star" button on both the 30D and 5DII (but not with my hearing aids turned off!!).

As an aside, I don't doubt that you've been using BBF for "years" on your 50D, but I bet I've been using it a bit longer on my 30D.

Glenn

[Dave Humphries]

You may have noticed that the image in the viewfinder is shifted when the mirror drops down again after the image is captured which is the result of this feature.

Now you mention it, I have indeed seen this effect on some occasions, glad it's not my eyes playing up!

Mike, just in case I was misleading you all, I have tried this again - lest I was mistaken in the 'heat' of field shooting, but I was correct; pressing either AF-ON or half pressing the shutter button starts (or maintains) VR.

I also had a look in the (paper) manual - you are correct, it's very lacking in detail on VR operation.

I did note (p.77) that using AF-ON over-rides the focus/release mode selections (in a1 and a2) and will always take the picture regardless of focus being achieved - and it disables the V/F indicator - but I can't say I found either to be a problem given my far better success rate

Early days, but I'm sure the AF is better on D7100 than D5000 (as it should be) e.g. in low light and speed - in fact I'm suspecting it may allow the lens more 'juice' to focus quicker too.

Cheers,