AF problem: Camera or lens ?

jgoetz4 · January 15, 2009

Good Evening Folks,
I noticed my 70-300 IS lens was not as sharp as I believe it should be. I did a comparison test at various FL's, both af & mf, IS off. The test object was 25' away.You can clearly see a difference (mf sharper) in the following pictures, both at 300mm, both right from the camera, no pp. Not sure if it's the camera or the lens. The camera is still under warranty. I had a similiar problem with my Tokina 80-400mm using af. I never did the mf test. Now I wonder if that lens was better then I thought. What do you think ?
Have a good evening

Jim...

jgoetz4 · January 15, 2009

And mf

Candid Arts · January 15, 2009

What aperture are you using?

I don't believe the 40D has it, but the 50D has a micro adjustment for lenses that you can adjust for. Maybe look into if the 40D has it? On top of that, do you have you focusing point set to all 9 so the camera auto picks, or did you select a specific one for the camera to focus to?

jgoetz4 · January 15, 2009

Candid Arts wrote:

What aperture are you using?

I don't believe the 40D has it, but the 50D has a micro adjustment for lenses that you can adjust for. Maybe look into if the 40D has it? On top of that, do you have you focusing point set to all 9 so the camera auto picks, or did you select a specific one for the camera to focus to?

Good Evening and thanks for your response

The 40D does not have MA unless you install the 'hack'. Both pics were taken at 300mm, f8, center point focus, tripod mounted. Thanks again

Have a good evening

Jim...

ziggy53 · January 15, 2009

Tripod or hand held?

Take a series using each technique, AF and manual focus, and see if there is a trend.

Candid Arts · January 15, 2009

ziggy53 wrote:

Tripod or hand held?

Take a series using each technique, AF and manual focus, and see if there is a trend.

jgoetz4 wrote:

Both pics were taken at 300mm, f8, center point focus, tripod mounted.

jgoetz4 · January 15, 2009

ziggy53 wrote:

Tripod or hand held?

Take a series using each technique, AF and manual focus, and see if there is a trend.

Good Evening Ziggy and thanks for your response

I'm one step ahead of you on this one

I started with 100mm, then 200mm then finally 300mm, both af & mf, apertures from 5.0 to 8.0, IS off, center point focus, ( I use that all the time) all tripod mounted, straight from the camera, just cropped, and they all have the same results: mf is clearly sharper. I wonder if my old Tokina 80-400mm suffered the same fate. Thanks again

Have a good evening

Jim...

ziggy53 · January 16, 2009

Candid Arts wrote:

Thanks, I can be oblivious to the obvious sometimes.

ziggy53 · January 16, 2009

jgoetz4 wrote:

Good Evening Ziggy and thanks for your response
I'm one step ahead of you on this one I started with 100mm, then 200mm then finally 300mm, both af & mf, apertures from 5.0 to 8.0, IS off, center point focus, ( I use that all the time) all tripod mounted, straight from the camera, just cropped, and they all have the same results: mf is clearly sharper. I wonder if my old Tokina 80-400mm suffered the same fate. Thanks again
Have a good evening
Jim...

If you don't have a problem with your other lenses then there is nothing wrong with the camera body. It could be similar problems with the two long zooms however.

How much do you have to adjust the 70-300mm IS to bring it into focus manually after AF?
Is it just a "bump" of focus adjustment?

Candid Arts · January 16, 2009

ziggy53 wrote:

If you don't have a problem with your other lenses then there is nothing wrong with the camera body. It could be similar problems with the two long zooms however.

How much do you have to adjust the 70-300mm IS to bring it into focus manually after AF?
Is it just a "bump" of focus adjustment?

To test this, set the lens to AF, and auto focus. Then, without moving the camera, switch the lens to MF and adjust. Take note of how much you adjusted.

Kulla · January 16, 2009

jgoetz4 wrote:

Good Evening and thanks for your response
The 40D does not have MA unless you install the 'hack'. Both pics were taken at 300mm, f8, center point focus, tripod mounted. Thanks again
Have a good evening
Jim...

What 'hack' are you talking about? Something new or ?

The latest 'hack' that I'm aware of was video recording with 40D and that was it.

Cheers
Amar

jgoetz4 · January 16, 2009

ziggy53 wrote:

If you don't have a problem with your other lenses then there is nothing wrong with the camera body. It could be similar problems with the two long zooms however.

How much do you have to adjust the 70-300mm IS to bring it into focus manually after AF?
Is it just a "bump" of focus adjustment?

Morning Ziggy,
I don't recall having any af issues with my old 70-200 4.0. That lens was just plain sharp. My Tamron 17-50 & the 24-135 are also sharp. Yes, just a slight movement at most. I will retest those lenses later today. I'm curious now

Thanks again Ziggy

Have a good day

Jim...

jgoetz4 · January 16, 2009

Kulla wrote:

What 'hack' are you talking about? Something new or ?

The latest 'hack' that I'm aware of was video recording with 40D and that was it.

Cheers
Amar

Good Morning Amar,
I believe the same individual that 'hacked' the video, was able to perform ma
as well. Other 'missing features' were available, I believe.
Have a good day

Jim...

Kulla · January 16, 2009

jgoetz4 wrote:

Good Morning Amar,
I believe the same individual that 'hacked' the video, was able to perform ma
as well. Other 'missing features' were available, I believe.
Have a good day
Jim...

Hi Jim,

I'm reading chdk forum as well, but that guy who wrote those scrips is inacitve for a long time, so I wouldn't expect any news on that field soon.

Cheers
Amar

Candid Arts · January 16, 2009

Not to highjack this thread, but there is a hack that can make the 40D record video? Would this work for the 50D? What is the video quality? How do you get this and put it on the camera? Is it safe for the camera? Will it void the warranty?

I'll just start a new thread.

jgoetz4 · January 16, 2009

Candid Arts wrote:

Not to highjack this thread, but there is a hack that can make the 40D record video? Would this work for the 50D? What is the video quality? How do you get this and put it on the camera? Is it safe for the camera? Will it void the warranty?

I'll just start a new thread.

Good Afternoon,
Feel free to hijack, it doesn't bother me, as long as it's camera/lens related and as long as the Mods don't mind

I suggest doing a search on 'hacked Canon 40D' cameras, and see what you find, since I'm not sure what features would be available with the 'hack' Good luck

Have a good afternoon

Jim...

jgoetz4 · January 16, 2009

Kulla wrote:

Hi Jim,

I'm reading chdk forum as well, but that guy who wrote those scrips is inacitve for a long time, so I wouldn't expect any news on that field soon.

Cheers
Amar

Good Afternoon Amar,
Thanks for the update

Have a good day

Jim...

jgoetz4 · January 16, 2009

Good Evening Folks,
I tested my Tamron 24-135 at 100 & 135mm, both af & mf, and the pictures were fine. It sounds like something is loose internally in the 70-300. I sent an e-mail with pictures to Bernie at Pho-Tech.net to see what he thinks. The lens is out of warranty anyway. I also attached my 1.4x tc and shot at 420mm, f9.0, and that picture was sharp, mf of course. We'll see what happens. Thanks to all for your help & suggestions

Have a good evening folks

Jim...

jgoetz4 · January 17, 2009

Update !
Good Evening Folks,
I tested additional lenses earlier, and it appears that the camera's af is off. I shot a cereal box using af, mf and live view, tripod mounted. The live view was constant in terms of sharpness with all the lenses, with the mf coming in second. Not sure how it happened, but somehow, my af got whacked

It's still under warranty, so I'll send it back to Canon and see what they do.
Have a good evening

Jim...

jgoetz4 · January 25, 2009

AF Update
Good Evening Folks,
Let me say that Canon is quick to fix and just as quick to send it back

I sent my camera in last Monday, the 19th. Canon received it on the 20th. They authorized the warranty work on the 21st. Apparently they replaced the top assembly unit, adjusted the shutter speed & af, cleaned the sensor, checked all factory specs and updated the firmware, then they sent it out on the same day. I received it on the 23rd. Not bad. 5 business days total. I retested my lenses, particularly, my 70-300 IS. That lens is sharp, and the color/contrast is very good. Here are a few pictures from earlier today with the 70-300. The 1st one is Ginger at 275mm, wide open, cropped only, no pp.
Have a good evening

Jim...

jgoetz4 · January 25, 2009

The bird bath was shot at 300mm, wide open, and smart sharpened slightly.

jgoetz4 · January 25, 2009

The license plate was shot (250' +-) with my Kenko 1.4x tc at 300mm,f8. Cropped and edited.

jgoetz4 · January 25, 2009

And finally, Kane, the neighbors dog at 200mm,f8.
Have a good evening folks

Jim...

AF problem: Camera or lens ?

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