Dust question on the 1D3......help

Hello

I got my new 1D3 today .

But when i look through the veiw finder, with a lens on and without a lens i can see a couple of big dust spots .1 is in the top left corner, and the other is near the middle.And they are very noticable.

Now what i want to know is because i can see them through the view finder, are they on the sensor or are they on the mirror, or the white thing which has the fucus points on it, that is above the mirror ?.

I have tried the Rocket blower, which did'nt help.

The one by the middle really shows up when i take a shot at say f11 onwords on the shots.

Because i hav'nt a Canon service centre near by(i live in Bristol, UK).I was going to get that "Dust Aid" pack ?, is that one recommended ?.

Anyones advice would be great as looking at a big speck of dust is driving me mad .

Trying blowing toward the top of the camera from inside instead of at the sensor. That dust is on your focusing screen. You won't see it on a photo. Careful with the focusing screen. It scratches easily.

If it shows on photos I think it may be on the sensor but then again maybe that wouldn't show up through the viewfinder - suggesting mirror. I suppose you have tried putting it in sensor cleaning mode as described on p.132 or putting into manual cleaning mode and giving the sensor a blow as on p.135.

bgmoore wrote in post #4149951
Trying blowing toward the top of the camera from inside instead of at the sensor. That dust is on your focusing screen. You won't see it on a photo. Careful with the focusing screen. It scratches easily.

trouble is he states it does show up on images at f11.

bgmoore - As i've wrote it does show up on the shots.The middle speck of dust REALLY shows up.

racketman - Yeah ive done the sensor cleaning thing a few times, thats what made me think it could be on the mirror or the focus point screen.And i have done the mirror lock-up manual sensor clean, with the rocket blower.

Alan B wrote in post #4150006
bgmoore - As i've wrote it does show up on the shots.The middle speck of dust REALLY shows up.

racketman - Yeah ive done the sensor cleaning thing a few times, thats what made me think it could be on the mirror or the focus point screen.And i have done the mirror lock-up manual sensor clean, with the rocket blower.

Just by the way an SLR physically operates, if you see dust through the viewfinder, it is either in the prism, on the focusing screen ( top or bottom side ) or on the mirror. It is IMPOSSIBLE to look through the viewfinder and see dust on the sensor. Now if you have a spot in the viewfinder and a spot that shows up on your print, Id say you either have a dust particle that Planck himself would have loved to see OR ( and this is the more likely one ) youve got dust somewhere in/on your lens. You could have a spot on your mirror/focus screen and on your sensor also, but the chances are less. Whatever the case, it should just be noted that if youre seeing dust through the viewfinder, it has NOTHING to do with dust being on the sensor. Again, if there is dust coming out in your pictures, its probably on the sensor and thats not something you can see through the viewfinder.

Alan B wrote in post #4150006
bgmoore - As i've wrote it does show up on the shots.The middle speck of dust REALLY shows up.

racketman - Yeah ive done the sensor cleaning thing a few times, thats what made me think it could be on the mirror or the focus point screen.And i have done the mirror lock-up manual sensor clean, with the rocket blower.

Sorry I should read these when I'm awake.

Alan, just do a systematic cleaning:

1) run the sensor cleaning function
2) use manual cleaning mode and use a blower
3) use the blower on the mirror
4) open the focusing screen holder and use the blower on the focusing screen (be careful not to scratch it).

if you don't see any more dust on your images, your sensor is clean. if you don't see anymore dust in your images but you still see the spots, you have dust inside the viewfinder and that only canon can take out. if you still see dust on your images, chances are that you have a persistent bunny that will have to be removed either by canon or by using a wet method...

True - doesn't mean he hasn't got bags of dust on the sensor *as well*, of course.

Get a big blower (Rocket) as recommended above. Personally, I put my mk3 on a tripod so that the lens mount faces down. You can then get much more 'oomph' from the rocket-blower and - with luck - any dust will actually be blown out of the camera - rather than just redistributed around the insides.

I've still got specs on my sensor, but they only show up against light objects at quite a bit over f/10, so I'll leave them there until the camera can go back to Canon for a freeby clean.

bgmoore wrote in post #4149951
Trying blowing toward the top of the camera from inside instead of at the sensor. That dust is on your focusing screen. You won't see it on a photo. Careful with the focusing screen. It scratches easily.

No!! The thread starter should scratch it so he has to purchase a grid screen!

Hello and BIG thanks for your replys.

Right i did the white test.

Put on the 17-40L and shot something white at f22.And yes you are right the spots i am seeing through the view finder is NOT coming up on the shots .There is some very very tiny specks when zoomed in via the display screen on the back, but thats nothing.

So the big spots of dust is on, either the focus screen or the mirror.

Is it alright to "swob" the mirror with lens cleaning fluid and micro fibre sheets ?.Or will that damage it ?.

Oh and can the air from the rocket blower damage the focus point screen

EDIT - Just did a load of search reading, so i know the answer to my questions.

Alen, do NOT swab the mirror!!!!

i am willing to bet that the dust you are seeing is on the focusing screen or the viewfinder which is quite normal. the focusing screen is very easy to check because you can just take it out. if it is in the viewfinder, you can either just live with it (i did for a year almost) or send it to canon for cleaning.

Hi regards the focusing screen do you mean the screen with the focus points on, which is above the mirror when looking in ?.

If it is then how do i get that out

Oh and i'm going to give the area a good blasting with the blower tomorrow, as its a bit late know.

EDIT - Just googled it and found instuctions.But i will give it a blasting 1st

that's the one Alan. getting it out is SUPER EASY and this is also how you change focusing screens:

take off the lens.

look into the chamber on the top and you will see that the screen is sitting in a metal bracket and that there is a small metal tab toward the front

all you need to do to drop the screen is simply pull the tab toward you and the screen will just fall.

Whats wrong with swabbing the mirror?