Canon EF 100mm f/2.8 USM Macro Problem.

[eljorgo]

Hi all.

Looking for a few input from you guys:
I bought in summer 2010 a Canon EF 100mm f/2.8 USM Macro. Back then I had a EOS 400D body but I later switched it for a EOS 550D which I use at the present.
Things have been working very well since I got this lense whatever the body and other accessories were. No problems till last night.
I was photographing small creatures in a improvised white background in manual mode and the parameters were:

Shutter speed: 1/125
ISO: 100
A Speedlite 430EX II Flash was used too.

I was using the smaller aperture possible so all the animal would appear focused and using the speedlite power to the maximum so the picture still had good light on it. Around F/22 to F/29 most of the shots.
When I tried using F/32 (Very tiny indeed) I heard a strange noise after the shot being taken and the photo made no sense. Instead of having a small amount of light (as you use smaller apertures such as F/32 the photos start having less light on them) the photo was so bright I could not see nothing but white.
I was so confused I decide trying a series of tests against my other lens (Canon EF 24-70mm f/2.8L II USM) and every time I did there was no problem so I suspect neither the flash, the body camera or the EF 24-70mm f/2.8L II USM have problems.

Here are a few photos I took as examples:

Lense: Canon EF 24-70mm f/2.8L II USM (this one is I bought very recently and works marvelous.)

Shutter speed: 1/125
F/2.8
ISO 100



Shutter speed: 1/125
F/8.0
ISO 100



Shutter speed: 1/125
F/16
ISO 100



Shutter speed: 1/125
F/22
ISO 100


Like you guys can see no problem with Canon EF 24-70mm f/2.8L II USM. All seems just fine.

Now comes the problem:
Lense: Canon EF 100mm f/2.8 USM Macro

Shutter speed: 1/125
F/2.8
ISO 100




Shutter speed: 1/125
F/8.0
ISO 100




Shutter speed: 1/125
F/16
ISO 100




Shutter speed: 1/125
F/32
ISO 100




As you guys can see by the pictures It makes no sense having such a tiny aperture and so much light on it. I think maybe might be wrong with this lens. Still I hope Its a result of my poor knowledge instead and still am hopeful for a way out of this problem.
I'll leave it for you guys with lots more experience to comment on it.
Please leave any input you might have. This is driving me insane.
Thanks so much and sorry for poor English,

Jorge.

 

[o hey tyler]

Can you upload images with the EXIF intact? I know you said that the aperture was set to f/32, but perhaps the intact EXIF will show something on the contrary.

 

[Derrel]

Can you upload images with the EXIF intact? I know you said that the aperture was set to f/32, but perhaps the intact EXIF will show something on the contrary.

Tyler's correct about looking at the EXIF information--it can help diagnose a lot of problem issues. One possible issue could be that the lens diaphragm is malfunctioning. With your zoom lens, the overall level of exposure is quite consistent, and with the 100mm macro, the exposures vary wildly...which might indicate a problem with the diaphragm not stopping down properly each and every time.

 

[eljorgo]

Can you upload images with the EXIF intact? I know you said that the aperture was set to f/32, but perhaps the intact EXIF will show something on the contrary.

Tyler's correct about looking at the EXIF information--it can help diagnose a lot of problem issues. One possible issue could be that the lens diaphragm is malfunctioning. With your zoom lens, the overall level of exposure is quite consistent, and with the 100mm macro, the exposures vary wildly...which might indicate a problem with the diaphragm not stopping down properly each and every time.

Hey Guys. Thanks so much for the input.

Well I did do as you guys said.

Ive used this online viewer: Jeffrey's Exif viewer and also Downloaded Opanda PowerExif 1.2 Professional Trial. Both Exif's showed exactly how they supposed to. Frustrating indeed. Have no idea what to do now...
There is something definitely wrong with the diaphragm or near to that. I sometimes do photos under extreme moist conditions with this lense. I think 3 times in 3 years. It gets a few tiny splashes of fresh water but ive always cared the lens well after it. I gave it a period of a few days in a hermetic drying box. Last time was many months ago. Dont know if this was the cause for such a malfunction. What should I do now?

Ive tested all photos twice. Anyways here's one print screen of the F/32 photo.



Thank you so much.

 

[eljorgo]

Hi Everyone

A little help here?

Thanks in advance
Best Regards.

Jorge

 

[o hey tyler]

Try stopping the lens down to F/32 and hitting the DoF preview button. Inspect through the front of the lens to see if it's contracting.

 

[eljorgo]

Try stopping the lens down to F/32 and hitting the DoF preview button. Inspect through the front of the lens to see if it's contracting.

Hi Tyler. Thanks for that tip. Am still very inexperienced in photography.
Well I've done what you said. I switched to F/32 and then pushed the DoF for over 60 times. It would contract and stop at very different diameters. Sometimes it barely contracted (leaving it nearly like F/2.8) this happened nearly every time. Out of endless times only 2 times it contracted to a tiny little gap. So yeah I suppose something is very wrong. Thus the fact that at F/22 It would contract way more and originate a way smaller circle than with F/32 witch isn't supposed to happen I guess.
I took several pictures with my phone while holding the button. All these pics were taken at F/32. So yeah you can see it would contract at a wide range of diameters with a special tendency to wide open allowing a lot of light. This is not good..
I feel like I have tied hands... What are my options guys? Thanks so much for the help so far.

Pictures with F/32 while holding DoF.









I think this last one was near. But like i said this diameter only showed 2 times out of ~60


Cheers,
Jorge

 

[Josh66]

I would go ahead and send it in to Canon... This doesn't really seem like something you can fix yourself.

 

[eljorgo]

I would go ahead and send it in to Canon... This doesn't really seem like something you can fix yourself.

Well warranty is gone... So I would have to pay right... Any ideas of which procedures they would have to do and how much it would be a repair? I've never had any lens sent to repair before but I'm saying this because i dont feel like playing as much as a new lens would cost. That would make no sense.

Thanks everyone for the input.
Any more tips/ advice I should consider?

Cheers people,
Jorge.

 

[Josh66]

Yes you will have to pay...

I would expect it to be a lot less than a whole new lens would cost...

Not sure how much it'll be, but you'll have to pay to ship it to them, they'll look at it and decide what needs fixed, then give you a quote. From there you either tell them to go ahead and fix it or send it back.