Lens Compatiblility Question

JMBriggs · Jul 26, 2011

Ok so I have a t1i and I am saving to buy a 5D mark ii. I also am saving to buy some L glass, but people keep telling me something about L series not working with some cameras... Umm help? What is everyone talking about? I know that a regular EF-S won't work with the 5D because the 5D is a full frame and it will show vignette with an EF-S lens but it would work with L series right? Also I have a completely different ?. I have been noticing that with my t1i and my 55-250 that I am getting a very slight blur across my whole image is this from the quality of lens or could it be my camera needs repaired?

KmH · Jul 26, 2011

Canon's EF-S lenses will not mount on EF camera bodies, but EF lenses will mount on EF-S camera bodies.

However, Nikon DX lenses don't project a large enough image circle to fully illumunate an FX (full frame) image sensor. Nikon FX cameras are set by default to detect a DX lens is mounted, and then only use an APS-C image sensor sized portion of the FX image sensor. The auto DX detect can be disabled in the menus and the various DX lenses will deliver varying amounts of vignetting on the FX lens, some come quite close to using the entire FX image sensor.

JMBriggs said:
I have been noticing that with my t1i and my 55-250 that I am getting a very slight blur across my whole image is this from the quality of lens or could it be my camera needs repaired?

You'll need to post a sample photo.

JMBriggs · Jul 27, 2011

Here is a sample picture of the fuzziness I was talking about... I did sharpen it with aperture for mac. It is very obvious in the lines of their plaid shirts. The picture was taken at 250mm at iso 200, f5.6 and 1/200 the lens was set to af and was set to continually refocus because my subjects were walking away from me.

Gaerek · Jul 27, 2011

JMBriggs said:
Here is a sample picture of the fuzziness I was talking about... I did sharpen it with aperture for mac. It is very obvious in the lines of their plaid shirts.

It honestly looks like you missed focus. There's of course a chance the lens is messed up. It could also be camera shake I suppose. What was your shutter speed?

Gaerek · Jul 27, 2011

You edited while I was posting. With the new info, it really seems to be a focus issue. See if you have the same problem on a stationary object. Put it on a tripod to remove camera shake as a possibility. What focal length were you at? Depending on your focal length, 1/200 might not have been enough to eliminate camera shake.

EDIT: Just saw that you were at 250mm. You probably should have been close 1/500 (1/320 might have been sufficient). Almost certainly camera shake.

JMBriggs · Jul 27, 2011

Thanks for the advice I will try pushing up my shutter speed. But this was just a sample picture.. I am getting the same fuzz in a lot of my recent work... Now that I know camera shake can still happen at 1/200 I am going to go through and check the speed of my other pictures that have the same softness...

Gaerek · Jul 27, 2011

JMBriggs said:
Thanks for the advice I will try pushing up my shutter speed. But this was just a sample picture.. I am getting the same fuzz in a lot of my recent work... Now that I know camera shake can still happen at 1/200 I am going to go through and check the speed of my other pictures that have the same softness...

The rule of thumb is your shutter speed should be at least 1 / focal length, but that was with FF or 35mm. You need to factor in your crop factor. So in that case, you should be at a minimum 1/400. Personally, I'd push it up to 1/500, but that's because I'm a naturally shaky person, YRMV.

KmH · Jul 27, 2011

Using Continuous focus usually also invokes release priority and turns off focus priority.

When the camera is in focus priority the shutter will not release unless focus has been achieved. When the camera is in release priority the shutter will release when ever it is actuated, even if focus has not been achieved.

In other words, because you were in continuous focus mode, you could have released the shutter as the lens was re-focusing.

Even with an effective focal length of 400, you should be able to hand hold with a 1/200 shutter speed. I recommend you review and/or refine your camera holding technique.

Da Grip - http://lightingmods.blogspot.com/2008/10/tip-camera-holding-technique.html

http://www.digital-photography-school.com/how-to-avoid-camera-shake

http://www.moosepeterson.com/techtips/shortlens.html

I also add a vertical grip to all my camera bodies that don't have one built-in, to both increase the weight of the camera and enhance the holding area available.

AgentDrex · Jul 27, 2011

the fuzziness is definately due to blur from the low shutter speed...how do I know...most of my photos come out that way...I get the ratio right for the cropped frame sensor...but I have kinetic tremor and so its hit and miss a lot...especially in lower light situations...like this photo seems to have been taken in...

gsgary · Jul 27, 2011

Your shutter speed was not fast enough for the focal length you used so i would say you are not ready for a 5Dmk2

JMBriggs · Jul 28, 2011

Thanks for sharing those links. They were awesome. I went back through most of my recent pictures and found that 90% of them were blurred and at a shutter speed of 1/320 or less so yes you were all right.
BTW my camera won't let me take a picture without being in focus so if that was the problem it was just behinf from them walking away...
Also to the person who said I'm not ready for the 5D Mark ii your right.... But by the time I can finally afford it I will be! Anymore tips just let me know!

KmH · Jul 28, 2011

JMBriggs said:
BTW my camera won't let me take a picture without being in focus

Sure it will. You need to re-read you camera user's manual.

I would look the page # up for you, but it looks like Canon has taken all of their user's manuals offline.