I've just read the review for the new EOS3 and although I'm stunned by the specs and feel the need to go out and buy one immediately (I wish!), one thing puzzles me: 45 focussing points is an aweful lot to choose from, but why do they only cover 23% of the central frame? Is this not overkill for minimal gains? Surely a more useful eye-controlled (or manual) system would cover the whole or substantially the whole frame such that composing, metering and focussing can be done all at once? Spread them out a little surely?

Think about it, no more exposure lock, re-composing your shots within 4 sec or hold down AElock, switch to manual focus, etc, etc. Simply compose your shot how you want it (on tripod preferably), select the point(s) to focus on (or between for DOF), select the point(s) to meter off and shoot! Multiple subjects, some for focussing on and others for metering off, almost like a crude mouse driven screen telling the camera whats what in the frame. Taking pictures could be as easy as compose, point, point again and shoot, or am I just living in dream land?

I suspect that its either the eye-control or auto-focussing which fails on the frame peripheral? Please confirm or explain.

-- Tim Jeffes (tpf20@cam.ac.uk), January 04, 1999

Answers

I was disappointed in this too. It isn't too bad though. If you look at a diagram of the sensor area it covers a fairly braod area of the screen. Not as much as I had hoped, but better than any other AF camera. I suspect the reason is physical size of the CMOS sensor that is used. If they made it bigger it would end up costing a LOT more. If you have an EOS camera now take the lens off and trip the shutter on bulb. This will move the mirror out of the way, and you can see the sensor. The space it takes up is larger than you would think.

-- Brad (reloader@webtv.net), January 04, 1999.

I also dream of a camera with 100% AF pt covering, and more important, without any visible rectangles inside the viewfinder before focusing confirmed.

-- Eric Ung (ung@chevalier.net), January 05, 1999.

It's not just the sensor size that's a consideration. The AF sensor sees through the mirror, which needs a section semi-silvered or otherwise made translucent. Doing this for the complete image size is not a trival matter.

-- Danny Weber (danny_weber@compuserve.com), January 05, 1999.

Canon's new autofocus design presents an interesting problem. Is it an advancment or just a marketing selling point? I recenlty borrowed a friend's F5 to shoot some moving subjects. I covers about the same % of the viewfinder as the EOS3 despite having fewer sensors. It easily tracks subjects as they move from one autofocus zone to the next. The F100 uses the same layout as the F5. So what does the 45 points buy you on a practical level. Time, and our experience will tell.

-- STanley McManus (stanshooter@mailexcite.com), January 05, 1999.

i think 45 points is only an advantage for eye selection. with the 5 points on my eos-5 i still have to point to focus, then re-frame to shoot about 50% of the shots, because what i want to focus on is not directly under a selection point. but it's better then with 1 point because the amount i have to re-frame is MUCH less.

with 45 points pretty much everything is under an AF point. (as long as it's in the central area) so you can just look and shoot as advertised. i DO wish the AF area covered more of the frame, though. at least out to the "rule of thirds" verticies, maybe.

-- Sean Hester (seanh@ncfweb.net), January 05, 1999.

I think I agree with Stanley McManus. I too am of the opinion that at present 45 focus points so densely packed is a marketing gimmic and overkill, since other supposed inferior camera systems do the same job. So why has Cannon done this? My hope is that they share our vision of complete frame coverage (or at least 2/3rds) in the long-term but they thought they had better try their algorithm for 45 points first before adding more or spreading them out more, since I appreciate that 45 points does pose quite a few extra programming nightmares especially when one tries servo auto-focus. I wrote the initial posting in the hope to confirm Cannon's long-term plan. I too appreciate that the CMOS sensor cost rises with increased size, but the thing is already quite large isn't it? I too appreciate that the mirror needs to be partially silvered under every focus point, but 45 points must be sufficient to still have full frame coverage surely? Add 4 more and take it to 49 and have a grid 7x7. No extra cost apart from larger sensors.

The idea that one can define separate focus point(s) (for single point focus or DOF) and light metering can only be practically achieved if full frame auto-focus coverage is done. Personally I find the DOF setting on my EOS useful, yet at the same time useless (I do mainly landscape photography). The reason I say this is, DOF is one of the only things a photographer can't do with manual settings. Sure, he can guess it, but who truely knows how to judge distances at anything more than a few meters? What I tend to do is use my DOF setting to judge focussing distance and aperture, then switch to manual focus and Av, set the same aperture with Av and leave the focussing unchanged but more importantly unchangable by my camera too, recompose on a tripod and shoot. Quite a lengthy debacle. Okay, maybe its my technique which is wrong here, but I'm sorry I just can't fiddle with tripods and hold my finger half-down on a shutter release while recomposing with DOF, then stand back and hit my remote before 4 sec is up. Neither can I judge DOF accurately enough to know where to set the focul distance, aperture is generally not a problem - just use the maximum without getting into silly shutter speeds and close to reciprocal failure.

If Cannon would give me a system where I could do all the technical stuff (metering and focussing) on my tripod then the order of meter-focus-compose could me changed to compose-focus-meter which to be honest gives the photographer a great deal more time to concentrate on his art (composure). Correct me if I'm wrong, but is this not the logical order of events and the only way a wildlife or sports photographer can really work? I see full frame focus point coverage as a huge step in this direction. A custom function to set some preset circle of confusion sizes for DOF calculation would be a nice addition too. I've heard too many complain that AElock is rubbish if it only locks for a few seconds and that "wouldn't it be nice if Cannon followed .... and made AElock permanent", well no recomposing means no need for AElock usage anymore.

-- Tim Jeffes (tpf20@cam.ac.uk), January 06, 1999.

Sorry, I should have said compose-focus-meter-recompose changed to compose-focus-meter to stress the gains as I see them.

Thanx to all who responded to my query.

-- Tim Jeffes (tpf20@cam.ac.uk), January 06, 1999.

I looked at an EOS 3 at a local camera shop and was surprised at the amount of viewfinder space the AF area actually covers. Looks like more than 23% to me.

All the flashing red lights seemed distracting; however, I suspect one might get used to it.

The goal of multiple focus points is of course to allow AF for the off-center subject without having to lock focus and recompose.

How far off center one wants the user to be able to AF is the issue.

Only AF over the entire viewing area will permit AF for all potential subjects, but I suspect that there is an area that if covered would take care of all but the most unusual compositions.

I would think that if there were AF spots at the points of intersection in the traditional rule-of-thirds diagram plus the center, plus one intermediate spot in each direction -- makes a total of 15 -- that would take care of practically every real-world situation for most of us.

-- John Wall (john_wall@ncsu.edu), January 06, 1999.

the first rumor i heard about the "new canon 1n replacement camera" a year ago mentioned 15 AF points. i immediatly immagined what john just suggested. (actually i imagined the 5 points on my eos-5 replicated 1/3 up the frame and 1/3 down the frame for a total of 15) i would actually be happier with that then what the eos-3 gives you. oh well...

-- Sean Hester (seanh@ncfweb.net), January 06, 1999.

Tim - the Canon DOF function is just a simple approximation of the "true" optimal focus point. They don't do any fancy calculation. They could, but they don't. Here's a quote from a Canon Technical Specialist on the subject (from the Canon EOS FAQ files):

"...In any case, the EOS Depth AE calculations involve adding the defocus amount for DEP 1 to the defocus amount for DEP 2 to ascertain the total defocus amount. It then becomes a simple matter to place an intermediate focusing point 7/17 of the way from the near point to the far point. The 7/17 figure was selected by the EOS Depth AE system designers based on its accuracy for "normal" subject distances, not extreme close-up photography..."

-- Bob Atkins (bobatkins@hotmail.com), January 06, 1999.

Are you folks really thinking that that this technology will help your photography or is it the "be the first kid on the block to have... syndrome"? Honestly now, will 45 focusing points help your composition or exposure metering? Do you really "need" this camera or are holes burning in your pockets to spend money? I submit many people are enamoured with "bells and whistles" more than real creativity. This should set off a rash of flames!

-- Jeff Hallett (franjeff@alltel.net), February 05, 1999.

all you "need" and some film and a box with a hole.

more AF points would make picture taking faster for me. probably not "better" but less of a hassle. isn't that what ALL camera gadgets do? internal metering, AF, etc, etc, etc... they're all to make the process EASIER, not BETTER.

so... "help my photography"? i say YES. it'll make it faster, which is a help.

-- Sean Hester (seanh@ncfweb.net), February 05, 1999.

Why is it that Jeff Hallett contributes nothing to this conversation? What is it that makes a technophobe afraid of technology? Jeff, I separate photography into two very distinct parts: The ART or picture taking and the SCIENCE of picture taking. At present, taking pictures still involves thinking about the ART (composure etc), then doing the SCIENCE (focussing, metering etc) then back to the ART (recomposure). If I am given a system where I can first think about the ART then do the SCIENCE then yes I believe my photography has been improved. Improved because I will take less time and my creativity (ART) needn't be spoilt by having to think about the SCIENCE. To think that all these gadgets will make better pitures involves more than thinking in terms of the final product. All the features in the world won't improve my ART, that's obvious and not worth dicussing. But you have to account for the steps one took to get to a good composition. Anyone given infinite time, infinite film and a manual focus SLR would be able to take at least one near perfect picture (by pure chance mind you, but if all you care for is the final picture then what do you care how long or to what lengths one went to take it?).

Enough said.

-- Tim Jeffes (tpf20@cam.ac.uk), February 06, 1999.

My point is Tim, that I believe I can go out shooting ,with you,and with my humble lowly A2,and produce an ARTFULLY composed and SCIENTIFICALLY designed image as you would produce with the EOS 3! I don,t feel that I need ultra- high tech to make me a better shooter and many pros feel the same way! If you feel that a few more focusing points and eye control gets you a better shot then go for it! I think we have overdone this so if you wish to flame again, burn it it up bud! I feel very comfortable and satisfied with most of my gear.

-- Jeff Hallett (franjeff@alltel.net), February 06, 1999.

the thing is some people LIKE the "science" part of photography, and some people don't, and think it only gets in the way of the "art" part. let those people buy cameras with gadgets to do the science for them. (it's when you can buy a camera that claims to help you with the "art" part that i'll get worried)

actually an A2 is a pretty advanced camera. it's doing lots of the science for you. (unless you turn those features off) i'm surprised one more feature put you over the edge into thinking that we've gone too far.

i suppose if you had an n90s right before the f5 was announced, you'd figure that RGB metering was "too far"?

-- Sean Hester (seanh@ncfweb.net), February 08, 1999.

Sean, Ck the features and specs on the EOS 3. I,d say it has a few more than ONE feature over the A2. Actually my 2nd body is an older Elan and it works fine for me too. As I said, I am satisfied with my gear. Been published, won contests, slides continue to improve with every roll..... OK??? JEEEZZZ. Let,s be done with this.

-- Jeff Hallett (franjeff@alltel.net), February 08, 1999.