Dust!

Suddenly, without warning, Adrian Boliston exclaimed (7/22/2007 8:44 PM):
> "jmc" <NOnewsgroupsSPAM DeleteThis @NOjodiBODY.HOMEus> wrote in message
> news:5ggmr7F3f13dgU1@mid.individual.net...
>
>> I have a Canon Digital Rebel XTi (EOS 400D). There's dust clearly visible
>> through the viewfinder, even with the lens off. I've cleaned the mirror,
>> but the dust is still there.
>
> The dust will be on the focussing screen (just above the mirror, facing
> downwards)
>
> Cheers adrian www.boliston.co.uk
>
>

Thank you. I feel like a victim in a thriller: "look UP!"

Is canned air the best way to clean the innards? It was really hard,
even with my small hands, to clear the dust off of that screen.

jmc
 >> Stay informed about: Dust! 

"jmc" <NOnewsgroupsSPAM.RemoveThis@NOjodiBODY.HOMEus> wrote in message
news:5ggmr7F3f13dgU1@mid.individual.net...
>I have a Canon Digital Rebel XTi (EOS 400D). There's dust clearly visible
>through the viewfinder, even with the lens off. I've cleaned the mirror,
>but the dust is still there.
>
> How do I clean it off? I don't have any compressed air, and wasn't sure
> anyway whether that's safe to blow into my camera's innards anyway.
>
> Thanks for any help.
>
> jmc

Hi.

As I said in a slightly earlier thread, Mirror cleaning is something which
should only ever be done once or twice in a lifetime (yours not the
camera's).

These Mirrors are surface silvered, and the least thing can cause permanent
scratches.

If the dust is moderate, and does not obstruct your VF view of the Image,
and does not appear on the Image itself, just ignore it.

If great black lumps show in the VF, and a quick rub with a CLEAN lens brush
or wipe on the underside of the Fresnel Screen, (above the mirror), does not
get rid of them, then they are inside the VF optics and that will require a
visit to the Service Centre.

Roy G
 >> Stay informed about: Dust! 

This message is not archived
 >> Stay informed about: Dust! 

"jmc" <NOnewsgroupsSPAM DeleteThis @NOjodiBODY.HOMEus> wrote in message
news:5ggu0eF3gaekiU1@mid.individual.net...

> Is canned air the best way to clean the innards? It was really hard, even
> with my small hands, to clear the dust off of that screen.

I get the odd annoying bit of dust on the focussing screen, but have used a
small microfibre lens cloth to shift it, but it does not seem to get rid of
the very tiny specks, but they don't worry me too much. I usually carry a
giotto rocket blower which shifts larger bits of dust before resorting to a
cloth. With canned air I would worry about blowing propellant onto the
screen, but some canned airs are better than others I understand.
 >> Stay informed about: Dust! 

On Jul 22, 7:40 am, jmc <NOnewsgroupsS... DeleteThis @NOjodiBODY.HOMEus> wrote:
> Suddenly, without warning, Adrian Boliston exclaimed (7/22/2007 8:44 PM):
>
> > "jmc" <NOnewsgroupsS... DeleteThis @NOjodiBODY.HOMEus> wrote in message
> >news:5ggmr7F3f13dgU1@mid.individual.net...
>
> >> I have a Canon Digital Rebel XTi (EOS 400D). There's dust clearly visible
> >> through the viewfinder, even with the lens off. I've cleaned the mirror,
> >> but the dust is still there.
>
> > The dust will be on the focussing screen (just above the mirror, facing
> > downwards)
>
> > Cheers adrianwww.boliston.co.uk
>
> Thank you. I feel like a victim in a thriller: "look UP!"
>
> Is canned air the best way to clean the innards? It was really hard,
> even with my small hands, to clear the dust off of that screen.
>
> jmc


Never use canned air, the propellant is nasty and difficult to remove,
the mirror should not be touched with anything, very delicate. Use a
Rocket Blower or an ear syringe from the drugstore, the disadvantage
of the latter is the inhale the dust, and after a while you are
blowing dust around. Dust in the viewfinder is more annoying than a
true problem. But if you have dust there shoot a few pics of the sky
at f16, see if you have dust on the AA filter that covers the sensor.

Tom
 >> Stay informed about: Dust! 

On Jul 22, 7:40 am, jmc <NOnewsgroupsS....TakeThisOut@NOjodiBODY.HOMEus> wrote:
> Suddenly, without warning, Adrian Boliston exclaimed (7/22/2007 8:44 PM):
>
> > "jmc" <NOnewsgroupsS....TakeThisOut@NOjodiBODY.HOMEus> wrote in message
> >news:5ggmr7F3f13dgU1@mid.individual.net...
>
> >> I have a Canon Digital Rebel XTi (EOS 400D). There's dust clearly visible
> >> through the viewfinder, even with the lens off. I've cleaned the mirror,
> >> but the dust is still there.
>
> > The dust will be on the focussing screen (just above the mirror, facing
> > downwards)
>
> > Cheers adrianwww.boliston.co.uk
>
> Thank you. I feel like a victim in a thriller: "look UP!"
>
> Is canned air the best way to clean the innards? It was really hard,
> even with my small hands, to clear the dust off of that screen.
>
> jmc


Never use canned air, the propellant is nasty and difficult to remove,
the mirror should not be touched with anything, very delicate. Use a
Rocket Blower or an ear syringe from the drugstore, the disadvantage
of the latter is the inhale the dust, and after a while you are
blowing dust around. Dust in the viewfinder is more annoying than a
true problem. But if you have dust there shoot a few pics of the sky
at f16, see if you have dust on the AA filter that covers the sensor.

Tom
 >> Stay informed about: Dust! 

jmc wrote:
> I have a Canon Digital Rebel XTi (EOS 400D). There's dust clearly
> visible through the viewfinder, even with the lens off. I've cleaned
> the mirror, but the dust is still there.
>
> How do I clean it off? I don't have any compressed air, and wasn't sure
> anyway whether that's safe to blow into my camera's innards anyway.
>
> Thanks for any help.
>
> jmc
Do not concern yourself with dust that is visible through the
viewfinder. Under NO circumstances use canned compressed air inside the
mirror chamber. Only use a squeeze bulb type blower such as a Giotto
Rocket or dedicated chamber brushes.

Your major problem will be dust on the low pass filter protecting the
sensor (the sensor itself is never directly exposed to dust.) This you
will discover when you find dust spots in large fields of color such as
sky. These spots can be fixed in post processing with PhotoShop, but can
become a real pain and all you can do is clean the low pass filter. Here
go to your camera manual and follow instructions to lock the mirror up
and expose the sensor. usually a sensor brush will solve the problem.
(never use the same brush you use for cleaning the chamber, and always
blow the brush off with a blower or compressed air first. NEVER TOUCH
the bristles with fingers to leave grease.) Take care not to move
shutter grease onto the low pass filter.

Sometimes dust on the low pass filter (the protective glass in front of
the sensor) is fixed and cannot be moved with a brush. Here is when you
will have to resort to a wet cleaning technique. Just use the right
tools. Even so you might have to repeat several times to remove really
persistent spots.
You might need to check and clean your lenses and any filters you might
be using for spots.

Anyway here are a few URLs for cleaning tools and information.


http://www.cleaningdigitalcameras.com/
http://www.photosol.com/
http://www.kinetronics.com/
http://www.2filter.com/prices/products/eclipse.html
https://www.micro-tools.com/store/home.aspx
http://www.visibledust.com/products.php

Good luck,
'Duck
 >> Stay informed about: Dust! 

Suddenly, without warning, Adrian Boliston exclaimed (7/22/2007 10:41 PM):
> "jmc" <NOnewsgroupsSPAM.DeleteThis@NOjodiBODY.HOMEus> wrote in message
> news:5ggu0eF3gaekiU1@mid.individual.net...
>
>> Is canned air the best way to clean the innards? It was really hard, even
>> with my small hands, to clear the dust off of that screen.
>
> I get the odd annoying bit of dust on the focussing screen, but have used a
> small microfibre lens cloth to shift it, but it does not seem to get rid of
> the very tiny specks, but they don't worry me too much. I usually carry a
> giotto rocket blower which shifts larger bits of dust before resorting to a
> cloth. With canned air I would worry about blowing propellant onto the
> screen, but some canned airs are better than others I understand.
>
>

Good point. I forgot about those little "manual" blowers. I'll drop by
the photo shop tomorrow and see if they carry them.

jmc
 >> Stay informed about: Dust!