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Old Oct 25, 2008, 11:30 AM   #41
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Hi Jim,

I think your patience finaly paid of. You just helped me find my error. Thank you for your patience.

I set AF central point according to the manual. It was blinking, so I "thought" it's been selected. Than I moved mode to macro and here is the problem. I read manual p.61 and it says you can select one point to focus where you want only in P, Tv, Av, and M mode (not in the Macro!).

Now I took a picture in Av and I'm attaching it. I think it's much better. What do you think? I put measuring point right on the middle figurine's blue/green flower

Next I'll try to check landscape. I'm afraid it might be another problem; if you use wide angle, close to 18 mm in the sunny day and use Landscape mode, without any objects close that could possiblydistract measuring system then the depth - of -field is between few feet and infinity and practically everything should be perfectelyfocused. But this is something that needs few more tests and than I'll let you know results

Thank you, George
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Old Oct 25, 2008, 12:26 PM   #42
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My entire take on your problems so far is using the scene modes and letting the camera decide the focus point to use.

You probably assumed that the tree in the center of the frame on your last landscape photo was the focus point. Yet, the camera's Autofocus may have decided that more of the focus points were towards the back, and told the lens to focus on infinity in that mode (and many lenses will focus "past" infinity, so you can't always go by depth of field charts if you want more of the closer portions in focus).

My take on the macro tests was that macro mode was probably telling the camera to use the focus point that found something closest to the camera (even if that focus point was not over something more prominent in the image).

Tell it what focus point to use and you'll probably solve your issues. ;-)

If you still think it's not working properly, test in it controlled conditions using something like books or cd covers staggered close together (as in the example I posted a link to using books on a table), making *sure* that you are selecting the focus point. Then, see what you get.


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Old Oct 26, 2008, 8:33 PM   #43
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The AF in your "Basic Zone" choices is always going to make use of the 9 points. And when you have multiple points flashing red, your XSi will try to choose the point that's closest to you as the focal point.

If you want to testyour landscape mode, chooselandscape as a "picture style" in one of the manual modes rather than the Landscape choice on your mode dial. This will allow you to set the center-point focus and jack up sharpness, contrast, etc., if you wish.




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Old Oct 27, 2008, 2:46 AM   #44
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For now just STOP using the scene modes, seriously theyare a bad idea; they fool you into thinking you are using a P&S camera which will do the work for you.

Use P or AV set at f8 instead, one shot AF, select the centre point. Try to work with that for a while and see if you can some good results.

If after a lot of shooting you still can't get it right, then sit down read the manual on how to use live view. Switch to MANUAL AF and live view and try to see just how sharp you can get your shots.


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Old Nov 4, 2008, 1:06 AM   #45
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I'm a new member but have been reading this web site and this forum for over 2 years. It all started when I purchased a Canon S3 a couple of years ago. then I went to a G7 which I love, and in the past 2 weeks I've added the XSi. Let me start by saying I've been shooting for about 45 years starting will a film hard bocy SLR Pentax in Germany and ending with a Canon FTB and many lenses. After 10 years I got so involved with work I basically gave up photography.

When Digital Cameras came out and I retired, all of that has changed. The problem is getting back into SLR's. I'm affraid the P&S's helped me to forget most of what I learned. Anyway, right out of the box I started having problems with the XSI AF. So I started looking all over the WEB for others with similar problems. I now see there are all kinds of debates on every web site about the XSi AutoFocus.

I shoot a lot of close up flower shots and a lot of landscapes. I've been fortunate enough to sell several via our local Art club. The very first flower I shot with the XSi was a big disappointment. For the $$$ I spent on this camera I was expecting great results, especially since my G7 has provided me excellent results on just about every picture I've taken. When I uploaded all the XSi shots to my PC into Canon's Zoombrowsers and enlarged to 100%, the flower was out of focus. Using INFO I check my setting and they were as expected. I tried a dozen more shots and several times I could get the surronding leaves in focus but not the center of the flower. Yes I'm using single spot focus AF, in Av mode at 55mm and f/8 at about 1/60. The manual focus was not any better. What I really found is that the focus ring in MF at 55mm is just too sensitive. If you turn the focus ring 1/4-3/8 from side to side you have gone from behind the flower to way in front of the flower. This is just way to sensitive.

The focus ring has to manage the focus for everything from 18mm up to 55mm. At 55mm the total movement of the ring is about 15 degrees and at 18mm it is only about 20 degrees.

So my initial assumption is that this camera is out of adjustment. I searched on the web for a good Focus Target and I found the one that many have used at 45 degree angle. When I first tested it in my kitchen I was getting Front Focus of about 3/4" to 1-1/2", but this was in low light condition. The next day I repeated the testing under better lighting conditions and double checked my camera setup. I found that this test is very sensitive to the distance and to the angle of the camera. I also found that you have to know the exact location of the Focal Plane of the camera so you can accurately set up the correct 45 degree angle. Once I had this corrected I got much better results, only about 2-6mm FrontFocus in AF mode. I should mention that all of this is with the KIT lense of 18-55 AF IS.

What I have sense discovered is that the AutoFocus of the XSi is a lot different from any other Canon Camera, especially since they came out with the 9 point system. The AF for one or 9 points works the same. It is not the same as the Contrast Focus system on P&S and even the Live mode.

The next thing I found out is that the new AF system is very contrast sensitive even if they don't call it Contrast focusing. My point is when I set up the Focus test chart outside in good sunlight at the exact correct position, I got absolutely perfect focus each and every time. The I swing the camera tripod over to where the flower is and shoot the flower,... and you guessed it, the leaves are in focus but not the flower. Now when I say focus, I mean at 100%, because I typically enlarge my images and I need that focus.

Some people might say, wow,.. your asking too much. I say "No-way", I've been shooting for 1-1/2 years with my G7 under every kind of condition and that 10 MP camera is always in focus.

So I did some more testing. I started shooting closeups of fall trees and their leaves and when I uploaded them, I got great focus. So I mixed in a few more flowers,... and they were not in focus. I do not understand the new XSi AF system nor do I know how it works, but it seems that it is almost color sensitive. By that I mean that it does not see sufficient contrast to set the correct focus on certain light wavelengths, especially things that are Magenta. Obvously "White flowers" are difficult to focus on because there is "NO Contrast" I am not saying the camera does not "Find and lock" on focus, as it clearly does since it shoots the picture. It just stops at the wrong point or gives up.

I've done the test with the other lense that came with the camera, the 75-300 MM AF iii, and I get somewhat better results, but still certain colors of flowers will not lock in focus. I've test this another way by shooting flowers with groups of dark green leaves just in front and just behind the center of the flower and what I get mostly is about 1/2" of front focus, but once or twice I've seen some Back focus.

Many people are telling those people that have complained about the XSi AF problem that they need to go back and learn to use their new camera or to read the book, and some have even suggested that people are expecting too much from a beginner DSL. I can't believe that from the large number of people having SOME kind of problem with AF that it can all be blaimed on these other factors.

As far as expectations, yes I paid a lot of $$$ for this camera and I expect it to create pictures better than my S3 or my G7. After all , both of those cameras have identical "Creative Modes" as the XSi DSLR.

Canon has agreed to check out the camera and I will be sending it and both lenses to them sometime this week. I have kept it so I could do more testing and prove to myself that it was either the camera or me. I learned a lot in doing so. Did I come to a final conclusion,... No. I have seen the camera give perfect results, but each time it was under ideal conditions. I have seen it give me poor results under perfect conditions. What really disappointed me was that I could not fix the problem even under the best condition using manual focus. I did get some better results using "Live Veiw" mode, but I decided if it takes that much hassle to shoot a good picture, then I have the wrong camera.

All of this comes down to only one thing,.... FOCUS. If the camera can't do it,... and I mean for all kinds of flowers and scenes,... then what good is it to me.

Yes I will upload some sample shots as soon as I get some time and find out how it works on the web site.
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Old Nov 4, 2008, 10:17 PM   #46
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I received theemail and phone call from Canon. Basically they always try to blame user error, never admit this camera has a real problem with focusing, since even with perfect condtition there is no single area well focused. In the telephone conversation I received ridiculous advice to take pics with f22. Well I tried it with exactely same result.

Here is the copy of an original email from CANON:

We received the images attached to your e-mail. When viewed on our system the area beneath the active autofocus point is in focus. In addition the focusing range or depth of field is consistent with the selected apertures(f/11 and f/14).

By looking at the exif data we see these images were captured with the neutral picture style. As this picture style is intended for further post processing 0 in camera sharpening is applied to captured images. This can produce images with a soft appearance and is normal. For improved sharpness we recommend using the standard picture style. Information on picture styles may be found on pages 67 and 68 in the camera instruction manual.

Should you require further assistance, please feel free to email us or visit our customer support website at http://www.canon.ca


Sincerely,

David M.
Technical Support Representative


It convinced me to takeanother approach. I read few reviews, than I checked ebay prices for this lense and brand new one "Buy Now" costs... $59.00 :!:.Conclusion: I've got what I paid for. I took camera back to the retailer and exchanged my EOS Rebel XSi walue $999 with two lenses included 18-55mm and 55-250. This time I took Canon 40D body only for $1050 plus great 28 - 135mm value $650 ( I read few reviews). End of trouble, I'm in love with it after I took justfew pics:-)The lens is glass, not a plastic
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Old Nov 5, 2008, 2:04 AM   #47
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Well it's a good thing you didn't try buying a $40,000 medium format digital camera instead.

http://www.luminous-landscape.com/reviews/kidding.shtml

Under the right conditions i.e. a 13x19 print even professional photographers can't tell the difference between the output produced by a $500 camera and a $40,000 camera.

So much confusion over the difference between focus and depth of field, and so little knowledge of digital imaging.

http://www.luminous-landscape.com/tu...harpness.shtml

Most XSi cameras are operating within spec. There is a very rapidly diminishing quality curve. You have to pay a lot more money to get better quality. It is probably now approaching the point where P&S cameras will provide better quality with almost zero effort for most photographers.

I take a lot of bad pictures. The reason for that is my skill level with the camera I own. The harder I work the better my pictures get. Spending more money on equipment does not generally make your photographs any better.

Want to take really terrible pictures? Get yourself a $40,000 DMF system and use the auto modes. :blah:
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Old Nov 5, 2008, 7:14 AM   #48
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psykita

None of the photos you've posted so far lead me to believe your camera is at fault.

Look... even with that last photo you posted shooting in Av mode, you were still letting the camera decide the focus point. The EXIF shows that no focus points were selected and the focus mode was Auto (if you read the instructions I posted before, you'll see that if you press SET, the camera will toggle between Center Point and Auto AF).

You're missing something somewhere in how you're using the camera, since none of your samples show that a focus point was selected by you. So, I don't doubt that Canon didn't find any problems when analyzing the samples you sent them.

If the 40D works better for you, great. But, if you see any issues, post some samples and let members help you figure out what's going wrong (in the case of the XSi photos you were posting, the entire issue appeared to be letting the camera decide what to focus on, since none of your samples show that you selected a focus point).


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Old Nov 5, 2008, 7:51 AM   #49
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jbird1938

You'll have a much shallower depth of field with a dSLR than you had with your G7 for the same subject framing and aperture. That's because the sensor in your G7 is very small in comparison, resulting in a much narrower angle of view for a given focal length.

So, because your actual focal length is much shorter than you'd use on a dSLR for the same framing at a given focus distance, you have a *lot* more depth of field with a point and shoot model like your G7.

Chances are, your entire problem is Depth of Field (able to get some parts of a flower looking sharp, but other parts are still soft).

For example, if you're using 55mm and f/8 at 12 inches from a flower with your XSi, guess what your Depth of Field is going to be? Approximately 0.15 inches in front of your focus point, and 0.15 inches in back of your focus point. That's only about 1/3 of an inch total depth of field. ;-) IOW, if you lean any at all after a half press to lock focus, you're going to see a problem with a depth of field that shallow.

See this Depth of Field calculator to get a better idea of how that works:

http://www.dofmaster.com/dofjs.html

Note that the actual focal range of the lens on your G7 is 7.4 to 44.4mm. So, you'll be using a much shorter actual focal length to get the same subject framing at a given focus distance (resulting in *much* greater depth of field than you'll have with the XSi for a given aperture setting). That's because this type of camera is using a very tiny sensor compared to sensors used in a dSLR.

If you need more depth of field, stop down your aperture a bit more (higher f/stop number). Just keep an eye on shutter speeds and use a tripod and/or increase ISO speed so that you don't start getting blur from camera shake


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Old Nov 5, 2008, 8:41 AM   #50
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I'm glad to hear that you've found a camera you're happy with psykita. But after all this back and forth, and allyour frustration, I have to wonder why you refused to at least test out theadviceyou got hereabout setting a single, centre AF point. :?

I'm very quickly learning that this DOF stuff might be my problem... the radical difference between what I was used to with my point and shoot and the limitation of my new DSLR.
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