Xti is taking better pics than my new t3i? What gives?

wayne.robbins wrote in post #14808458
I've read the thread, and here are things that I choose to point out or ask.
1. Are all of your shots wide open ? Your body lacks MFA, you should try shooting with the lens stopped down a bit- like 1 to 2 stops. If that helps- you may need to send the body and lens in for calibration- or stop down your lens. Poor lighting could also contribute. Try your targets outside, mid-day. Bright sun.
2. Another way to see this- is to go take a shot using the viewfinder, and take a similar shot using Liveview. If liveview is clearly sharper- then your setup needs to go into calibration.
3. When shooting from a tripod, use a remote or 10 second timer- to allow for the camera to settle. The RC-6 remote should work- IR- and costs about $30. It'll eliminate shake caused by pressing the button.
4. Homes/ offices- most are really poorly lit. It does no good to test the AF system out in poor lighting where the system is most inconsistent. Add a lot of light.
5. Monitors are poor subject matter to take pics of. You need things with contrast.. A wine bottle with a fancy label would be infinitely better. Or one with a basket type weave around the bottle.. Or a basket. Something with notable texture.
6. Are you selecting the center point for focusing ? One Shot mode? It's the most accurate on your camera.

You should consider getting a kit lens for this camera.. If it works- then rid yourself of it -as a kit.

Your XTI pushes your lenses a lot less than your T3i. Consider getting newer, better glass and upgrading them. Even between bodies- the XTI might have different sharpening and other levels set - compared to the t3i. Comparing output from raw- or from the neutral are your best bets.

clearly you didnt read the thread, because most of your questions would have been answered by page 5. I went back and did a focus chart test.


the only question you have not answered, is that I did shoot both outside in bright mid day sun and inside as well. Same results. And yes, when I stopped it down a few stops, the problem was less severe.

The body is currently getting repaired, canon acknowledged there is a problem with it.

wayne.robbins wrote in post #14808398
I'm not understanding why 1: This issue has persisted over an 8 month period 2: why you took this camera with you on an important- once in a lifetime trip. I read the first page- and the last- so far.

1. because I hadnt had a need to use it

2. I listened to the other people on this forum saying the problem was my sigma lenses, and thought that by not using those, the problem would be resolved.


Lesson learned: trust your gut.

waterrockets wrote in post #14809064
OP: I think you might be happier with a point and shoot. DSLRs have way too many settings and options to be a once-a-year tool for a beginner. The experience is much better if you invest the time to become an expert with your camera's performance and settings.

A Canon S100 or G12 will be so much easier to just pick up and go without investing the time it takes to master a T3i, and you have enough settings to control your shots when you want to.

LCD monitors are perfect with the right image. I did this MFA procedure, and it worked incredibly well using my laptop as the target. The process actually requires a monitor instead of a print, to get the moire pattern on live view.

Very quick MFA process:
http://www.northlight-images.co.uk …s3_af_micoadjus​tment.html

I've had a DSLR for 8 years and I know how to use them. I find your comment a bit insulting. Just cuz I was busy and didnt use it doesnt make me a beginner or because its defective it doesnt mean Im a novice.

How is any of this my fault? Its a bum camera, case closed. It has nothing to do with my knowledge or frequency of use has nothing to do with it. Posts like this aggravate me.

I'm truly sorry you took offense to my comment, and I am trying to be helpful. A DSLR user will generally push malfunctions through to resolution in short order, not put it back in the bag for 9 months and hope the problem doesn't continue.

There's nothing wrong, or "lesser" with a photographer being more aligned to a high-quality point and shoot. I don't see that as offensive.

I think a G12 is such a simple system that if it had a focus problem, you would have quickly exchanged it, and your honeymoon photos would have been perfect. (note, this is not an insult!)

sev wrote in post #14807698
drove it in today and dropped it off. the woman made it sound like it was an easy fix. should have it back in a few days. i still feel like i cant trust the camera though

You should wait until you get it back and test it before you develop feelings of trust about it one way or the other.

More precisely, once you get it back, just think of it like you just bought it -- you have no idea if it's good or not (but it probably is), and a few tests will show whether it has problems.


Why some people were saying that you couldn't trust your Sigma lenses when they all work properly on your XTi is quite beyond me. That they all work well on your XTi essentially eliminates the lenses as being the source of the problem. Some people just cannot think logically...

waterrockets wrote in post #14809629
........A DSLR user will generally push malfunctions through to resolution in short order, ...

Was this a scientific study or just a broad based assumption?

My brother is a dslr user who has never removed the kit lens from his Canon XT. I am constantly changing stuff around, upgrading equipment, testing lenses for back focus/front focus/shapness issues, etc. Which one of us would fall into your classification of a "dslr" user?

waterrockets wrote in post #14809629
I'm truly sorry you took offense to my comment, and I am trying to be helpful. A DSLR user will generally push malfunctions through to resolution in short order, not put it back in the bag for 9 months and hope the problem doesn't continue.

There's nothing wrong, or "lesser" with a photographer being more aligned to a high-quality point and shoot. I don't see that as offensive.

I think a G12 is such a simple system that if it had a focus problem, you would have quickly exchanged it, and your honeymoon photos would have been perfect. (note, this is not an insult!)

It's cool.

kcbrown wrote in post #14809647
You should wait until you get it back and test it before you develop feelings of trust about it one way or the other.

More precisely, once you get it back, just think of it like you just bought it -- you have no idea if it's good or not (but it probably is), and a few tests will show whether it has problems.


Why some people were saying that you couldn't trust your Sigma lenses when they all work properly on your XTi is quite beyond me. That they all work well on your XTi essentially eliminates the lenses as being the source of the problem. Some people just cannot think logically...

I totally agree, when I get it back I will run it through the same tests, see how it does. The lady at canon made it sound like a simple procedure.

As far as the lenses goes, I wholeheartedly agree.

jwp721 wrote in post #14809813
Was this a scientific study or just a broad based assumption?

My brother is a dslr user who has never removed the kit lens from his Canon XT. I am constantly changing stuff around, upgrading equipment, testing lenses for back focus/front focus/shapness issues, etc. Which one of us would fall into your classification of a "dslr" user?

I'd say someone who nitpicks my word choice would fall into the DSLR user classification The other would be fine with a G12 :P

I'm good though -- I don't want nits in my words.

http://www.lensrentals​.com …s-is-soft-and-other-myths

sev wrote in post #14809518
clearly you didnt read the thread, because most of your questions would have been answered by page 5. I went back and did a focus chart test.


the only question you have not answered, is that I did shoot both outside in bright mid day sun and inside as well. Same results. And yes, when I stopped it down a few stops, the problem was less severe.

The body is currently getting repaired, canon acknowledged there is a problem with it.

It's because of your focus test charts that I asked some of the questions ! Let me extrapolate. Your body does not have MFA. You can't adjust it- other than stopping it down. With some primes- shooting wide open ( f/1.8 ) you might run into where your camera body and lens are actually "off" more- because of the narrow DOF. 50mm lenses- for example - can be murder. Shooting stopped down or using liveview are about the only options - but your pics were only of f/1.8- which could be contributing.. On my crops- my Sigma 50mm f/1.4 - little fuzzy at 1.4- decent at 2- but really a PITA- because it's got a range where it likes to work.. too short- it blows. Too far away- same. Battery tests helped determined that this did happen. Research said this is kind of normal for a Sigma.

Other things, like did you test outside in bright light- might be obvious to some- and less to others. It was not obvious from reading thru the thread- so i asked. Personally, I prefer a batteries in a diagonal type of test over a paper chart. The battery test is better at determining front focusing/back focusing than a paper chart or shooting a monitor or other flat object. The paper chart is good for checking sharpness- but not really worth a darn if - if the shots aren't in focus. Most of the rest of my points are valid- and may or may not have been applicable to you. Points like using the timer- is not obvious to some. You may have used it, or you may not have- some can shoot all day- steady as a rock. I resort to this when checking- and I can't figure something out.

Hindsight is 20/20. I guess I've gotten lucky with bodies and lenses. Well, 'cept my first SLR- a film camera.. It was ok- but not as great as the tech today. The telephoto zoom was quite terrible- and I would not know how bad, often for till weeks later. I tend to forget that some use a camera only when the need arises, and sometimes gets put into a closet in the interim- for months on end. Next time, take it out a week or two before- shame that you missed out on your trip.

BTW: I figured that your lens liked your XTI more than it did the t3i. Not necessarily a sigma issue- I've got a few.. Figured more either a tolerance issue- or if the lens was older- perhaps pushing seeing issues within the lens that the XTI could not resolve.

wayne.robbins wrote in post #14810985
It's because of your focus test charts that I asked some of the questions ! Let me extrapolate. Your body does not have MFA. You can't adjust it- other than stopping it down. With some primes- shooting wide open ( f/1.8 ) you might run into where your camera body and lens are actually "off" more- because of the narrow DOF. 50mm lenses- for example - can be murder. Shooting stopped down or using liveview are about the only options - but your pics were only of f/1.8- which could be contributing.. On my crops- my Sigma 50mm f/1.4 - little fuzzy at 1.4- decent at 2- but really a PITA- because it's got a range where it likes to work.. too short- it blows. Too far away- same. Battery tests helped determined that this did happen. Research said this is kind of normal for a Sigma.

Other things, like did you test outside in bright light- might be obvious to some- and less to others. It was not obvious from reading thru the thread- so i asked. Personally, I prefer a batteries in a diagonal type of test over a paper chart. The battery test is better at determining front focusing/back focusing than a paper chart or shooting a monitor or other flat object. The paper chart is good for checking sharpness- but not really worth a darn if - if the shots aren't in focus. Most of the rest of my points are valid- and may or may not have been applicable to you. Points like using the timer- is not obvious to some. You may have used it, or you may not have- some can shoot all day- steady as a rock. I resort to this when checking- and I can't figure something out.

Hindsight is 20/20. I guess I've gotten lucky with bodies and lenses. Well, 'cept my first SLR- a film camera.. It was ok- but not as great as the tech today. The telephoto zoom was quite terrible- and I would not know how bad, often for till weeks later. I tend to forget that some use a camera only when the need arises, and sometimes gets put into a closet in the interim- for months on end. Next time, take it out a week or two before- shame that you missed out on your trip.

BTW: I figured that your lens liked your XTI more than it did the t3i. Not necessarily a sigma issue- I've got a few.. Figured more either a tolerance issue- or if the lens was older- perhaps pushing seeing issues within the lens that the XTI could not resolve.

Interesting about the battery approach. I would have thought that batteries would be too far apart, and you don't know if it's trying to focus on text on front or one of the edges halfway through. Am I just off in my scale of focus capabilities here?

I recently did my first MFAs on my 1D, and I found that mosaic method to be extremely sensitive. On my 70-200, the finest moves I could make with the focus ring made a huge difference to the mosaic patterns on the LCD (focus is very obvious).

I can't seem to find any post saying you tested live view focus vs viewfinder focus, despite several suggestions that you do so.

Well, just got the body back from Fedex, indeed something was wrong, confirmed by the work order:

Fantastic news, enjoy the T3i!