Help tech problem with focus

KIPAX

KIPAX

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KIPAX Lancashire UK
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Figuring out the subject for this message was difficult :)

Was photographing a football match and when i half pressed to focus.. the screen went dark... it looked like a fine dark grey wire mesh and could see the scene in front of me..

or like a million dark spots on screen...

hard to explain... would only clear when i pressed fully and took the pic...

this has happened twice.. two sperate matches and I cant replicate.. but am worried gonna happen more and is terminal.. once I can forgive and forget ..but not twice..

is this camera or lens...anyone? any ideas at all ?
 
What body/lens and aperture were you shooting at?

The obvious question is to check it wasn't the dof preview being hit by mistake?
 
Ok, do you mean screen or do you mean viewfinder?

If you mean screen then there are several things that could be going on, both mechanical or electronic.

If you meant viewfinder, there can only be one thing going on and that the lens stopping down. Other than the mirror, it's the only bit that moves between you and the scene you're looking at.

Was it the same lens on both occasions?
 
sorry..

1dmkII + sigma 120-300

same setup used for a long time and no problems... and it was the viewfinder that appeared to have a millions dots on it.. like a fine mesh
 
If you set the camera to the same settings and hit the dof preview does it look the same?
 
nope ... dof button does make it go dim... but what i am experiencing is a lot different.. you can actually see millions of dots.... like its half way between two thing... damm its hard to explain..

imagine a flash slideshow and theres a disolve effect between two pics... it looks like that.... only ones a pic and ones a blank screen and its stopped half way through the desolve effect
 
are the dots in sharp focus?

I'm trying to think what could possible be in the optical pathway that could cause that.
 
hard to tell.. they are the more prominant.. the only thing that gets rid is full shutter press.. if i depress or press some more nothing... only full shutter press gets rid.. which makes me think summat inside the camera might be sticking.. or the lens focus sticks....

Knowing if body or lens would help... i cant contact canon or sigma without a clue....

Arrgh presumed somewhere in camera world someone would know.. Have also asked on the canon forums but nowt so far :(
 
Have you tried a different body (if available) or different lens? Does half-pressing the shutter have the same effect?
 
becasue it only happend twice (on two different days) and I cant replicate it then it nigh on impossible to test like that.. It could happen again in a week or a month or it could get more often. without being able to make it happen again or knowing why then impossible to test..

I just presumed that if its happened to me then its bound to have happened to someone else at some time... seems not ...erk..
 
The only thing I can think of which will darken the screen other than the DOF button is a sticking diaphragm which isn't uncommon.
 
Having looked a lot closer.. if i focus on somehting BRIGHT and then slowly move towards DARK (ai servo) you can see that the viewfinder is made up of millions of dots..(try it.. its normal) I tried it on two bodies with diff lenses and you can see its like a mesh of dots just when your in the grey area going from bright to dark..

I can only presume that summat sticks inbetween focusing and you get exactly what does happen normally but you stop it dead..

Whers the "diaphragm" body or lens?... sorry no idea me :)
 
The diaphragm is another name for the aperture - or the blades which adjust the size of the aperture - it's in the lens.
 
googled it and can see people having problems but none describe it as the same .. in fact an hr or two on google finds me nothing like my post :( If only I could replicate it.

Now decided the best description is like a disolve effect between a light and dark picture
 
did the camera get wet/damp??
 
Nagh.. Its a 1d.. would have to drop it in a pond mate :)

I emailed sigma who suggested the problem could be the "interupter" . Does that ring a bell with anyone?

Have now sent it to them for checking and I am left with a sigma 70-200 which was hard work at droylsden last night... I have the 1.4 TC so I should be OK sat sunday matches.. but night matches yuk :(

Sigma say 2-3 week turnaround
 
OK UPDATE

I sent the lens to sigma UK who have looked at it and decided its the AF MOTOR that needs repair.. Cost 75 quid (well 60 odd and vat)

Have paid by CC and told could be up to 4 weeks from now.. arrgh.. on explaining my needs they put urgent on and maybe 2 weeks.

I am really struggling without it as well :(
 
14th April and the Lens is back.. Wow you can tell theres a new AF motor.. its so quick.. it must have snuck up on me and slowly gone worse and I ahdn't realised.. But a quick test now and I can see just how fast it is...
 
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