DPR Forum

Welcome to the Friendly Aisles!
DPRF is a photography forum with people from all over the world freely sharing their knowledge and love of photography. Everybody is welcome, from beginners to the experienced professional. Whether it is Medium Format, fullframe, APS-C, MFT or smaller formats. Digital or film. DPRF is a forum for everybody and for every format.
Enjoy this modern, easy to use software. Look also at our Reviews & Gallery!

SD14 Sensor & Viewfinder Cleaning

iMac

Active Member
Hi,

My SD14 recently returned from Sigma Service UK after having the Viewfinder Screen cleaned, Sigma had done a good job (even cleaning the Sensor too) the screen was spotless.

After minimal usage it has again returned to it's previous debris & dust covered state and the Sensor looked like it had chicken pox, absolutely covered with dust & debris.

The viewfinder screen on my new second SD14 has also acquired some dust & debris as has the Sensor.

As both cameras suffer from dust & debris on the Viewfinder Screen and on the Sensor, it seems that this is a major design fault that I have to accept and live with.
The 'bicycle pump' action of Sigma's zoom lenses is the likely culprit for this dirt and dust getting into the camera.
I wish that Sigma would market true Internal Focussing Zoom lenses, with all the action taking place behind glass, similar to my wife's Leica V-LUX 1.

I successfully cleaned the sensors of both cameras using the Artic Butterfly brush, removing every single speck of dust. An expensive item, but it does it's job superbly, providing the bristles are kept clear of the Mirror Chamber walls thus avoiding picking up any shutter mechanism lubricant.

Now the difficult bit, cleaning the SD14's Viewfinder Screen.
KatzEye Focussing Screen Installation Instructions for the Sigma SD9 & SD10 are of little use as the SD14 is of a different design.

The SD14 Viewfinder Screen comprises four parts, as follows,

Focussing Screen retaining frame.
A plastic screen engraved with the focussing points.
A horse shoe ('U' Shaped) shim.
A plastic magnifying screen.

Tools needed, a good Tweezer, mine are about 6" in length.
Latex Gloves, if you can work whilst wearing them!

To disassemble, remove the IR filter.

Examine the Focussing Screen assembly, make notes about it's position, depth etc.

Place a folded Micro Fibre Lens Cleaning cloth or a Pec Pad over the Mirror, important.
Release the Focussing Screen retaining frame using your fingernail, allowing the screen parts to fall gently onto the protected mirror. For now, Leave them lying there.

Before proceeding further, make notes & sketches detailing the exact position and relationship of each part, both to each other and to the camera.
Get your head in gear, you need to know which way is up!
Make notes as you remove each part with the tweezer, which way round in relationship to the camera bottom, which way up is the engraved side etc.

I washed the plastic parts using water and a little washing up liquid. After drying I cleaned the screens with an anti static Coated Lens Cleaner, this is Non-gas, Non-toxic, anti-static formula contains NO alcohol or solvents, made by Specsavers UK.

The difficult bit, re-assembly, only because it's a first time venture and the lack of truly positive parts location.

At each stage of the assembly, look through the Viewfinder Eyepiece (With the Camera Upside down) to ensure that dust has not been re-introduced!
Remember to clean both sides of the Viewfinder Eyepiece, before starting the re-assembly, this may be quite dirty!

Last part out is the first part in, using the tweezer, replace the magnifying screen, seating the two small tabs, ensure that the screen is level.
Next, replace the 'u' shaped shim ensuring that it is in close contact and correctly seated.
Replace the engraved screen (the right way up)
With the camera bottom facing upwards, replace the retaining frame, securing by pressing downwards (towards the Flash). You will hear it gently clicking into place.


Note:
Be careful not to deform the retaining frame, successful Viewfinder Screen retaining is dependent upon this frame!

It took me quite a while to position each part correctly.
Focussing screen alignment is not an issue, parts either fit properly or they don't!

Alignment can be checked as follows: (taken from the Yvind Strom's Compendium)
Place the camera flat on a table. Place a mirror (without a frame) at 90 deg in front of the camera so that you can see in the viewfinder where the mirror rests on the table.
If the bottom of the mirror ( where it rests on the table) does not look straight, it is a screen misalignment.

Cleaning the Focussing Screen may be a bridge too far for some, but it's not Rocket Science, it just requires careful work and attention to detail.

Best regards to all,

iMac


 
Thanks, IMac, for that excellent description!

Although, I'll admit, you've encouraged me to live with the dust for a while!

Jesse
 
Correction to SD14 Sensor & Viewfinder Cleaning

Hi Jesse,

iMac wrote:

"Last part out is the first part in, using the tweezer, replace the magnifying screen, seating the two small tabs, ensure that the screen is level.
Next, replace the 'u' shaped shim ensuring that it is in close contact and correctly seated.
Replace the engraved screen (the right way up)
With the camera bottom facing upwards, replace the retaining frame, securing by pressing downwards (towards the Flash). You will hear it gently clicking into place."

I'm sorry, this assembly order is incorrect, I incorrectly reversed the order when typing from my notes. This should read:

Last part out is the first part in, using the tweezer, replace the Engraved screen.
Next, replace the 'u' shaped shim ensuring that it is in close contact and correctly seated.
Replace the magnifying screen, seating the two small tabs, ensure that the screen is level.
With the camera bottom facing upwards, replace the retaining frame, securing by pressing downwards (towards the Flash). You will hear it gently clicking into place.

With the camera Bottom facing upwards and the Sigma Logo facing away from you, the Focussing Screen Disassembly is as follows:

1. Focussing Screen Retaining Frame.
2. Plastic Magnifying Lens.
3. 'U' shaped Shim.
4. Engraved Focussing Screen.

I have just removed and replaced the Focussing Screen, it really is quite easy to do.

When attempting to do something unfamiliar for the first time, it is a daunting prospect.
Even removing & replacing the IR Filter for the first time is also quite daunting.
We live and learn.

Regards,

iMac
 
It is really easy to remove the Focussing Screen Assembly, clean and replace.

My post was more about reinforcing the idea of getting the mind in gear.
It's amazing that with only four parts to contend with just how confusing this can be.

These comments do NOT apply to female Sigma owners. Women are far more suited to this task as they have a superior multi tasking brain, they are much more intelligent than us mere males. They're smarter than me anyhow.

I have cleaned the Focussing Screen on both my SD14's, even repeated the procedure to check my facts.
First time was a learning experience, but after that it took just a few minutes to do, like riding a push bike.

There has been a lot of hype written about the dangers of interfering with the focussing screen, pure drivel penned by those who have not attempted the procedure. The fear of the unknown...........

I'm close on 80 years old, if I can do it, everybody can, the separate parts of the Focussing Screen assembly when re-assembled, really fall into place only needing a little guidance at times.

Both the plastic screens are made from a soft material and easily scratched, with this in mind, it is advisable to wear Latex gloves, provides a secure grip on the parts and avoids the transfer of oil from the hands.

Have fun out there,

Best regards,

iMac
 
Very welcome guidance, I wonder if there is a diagram or official service procedure for this. I am unsure which way round the shims go ( I have two of them), also I find it astonishing that the light path en route to the focussing screen should go through a plastic magnifier on the way. I shall practise carefully and hope to cause no further distress to the system.
 
Back
Top