Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-11-2012, 05:28 PM   #1
Veteran Member
kcobain1992's Avatar

Join Date: Dec 2010
Location: Bucharest, Romania
Photos: Gallery
Posts: 1,409
To clean a focusing screen

Hi, I have found contradictory advice on the net regarding this subject, so I will try to explain my situation clearly. I have an MX which has a viewfinder not overly dirty, but nevertheless I would like it to be spotless (it's not scratched yet, just has some black marks here and there). I'm planning to clean it myself using the following procedure, and I'd love to hear opinions about it before doing any silly thing again:
- with a pair of gloves and tweezers, take the screen out and put it on a clean dish.
- take a blower and get the dirt off it, also blow in the MX pentaprism which might be as well dirty
- either immerse the screen in lighter fluid, or clean it with lighter fluid on a cotton bud (which one is better? will I ruin the screen?)
- at the end, remove any cotton lint with the brush end of a lenspen.
On a side note, where can I find shims for the Pentax MX? With the SMC-M 28mm, it's not showing exactly infinity when it should, so I think it's slightly front-focusing.

03-11-2012, 05:50 PM   #2
Site Supporter
Spodeworld's Avatar

Join Date: Aug 2011
Location: New Joisey
Photos: Gallery | Albums
Posts: 1,240
I've heard that the focusing screen is so delicate that even a cotton bud could harm it. Don't know what to say about lighter fluid.
03-11-2012, 05:55 PM   #3
Site Supporter




Join Date: Jun 2011
Location: Texas
Photos: Gallery
Posts: 1,149
Lighter fluid is likely to ruin the plastic screen. The plastic is also very soft (to mold the fine detail in the surface) so is easily marred by rubbing with anything. I'd try distilled water with a few drops of windex, immersing the screen to free any bits of foam (the usual stick stuff that gets on them), maybe use an ear syringe to squirt the solution against it, rinse with pure distilled water, blow it off with a rocket blower (while holding by the edges - it is so light it can be blown about if not held).
03-11-2012, 05:58 PM   #4
Forum Member
KansasPen's Avatar

Join Date: Apr 2011
Location: Kansas
Photos: Gallery | Albums
Posts: 73
I tried cleaning my K10D focusing screen when I was showing a lot of dust through the view finder. I had great success with blowing out the housing. However where it went downhill was wiping off the focusing screen. I used a microfiber cleaning cloth and nikon lens cleaning solution. It was never the same. Once placed back in the camera it was noticeably darker and there were fine scratches on it. I ended up buying a new screen to correct the problem. When they say not to touch the screen they mean it. I recommend just using an air blower.

03-11-2012, 06:04 PM   #5
Veteran Member
kcobain1992's Avatar

Join Date: Dec 2010
Location: Bucharest, Romania
Photos: Gallery
Posts: 1,409
Original Poster
Well have you personally ruined any focusing screen by touching it? Because I know of people who cut ME Super screens down to size for their DSLRs, and that kind of behaviour would most likely harm them more than a cotton swab. But I have a little fear too, so that's the reason why I'm asking.

QuoteOriginally posted by KansasPen Quote
I tried cleaning my K10D focusing screen when I was showing a lot of dust through the view finder. I had great success with blowing out the housing. However where it went downhill was wiping off the focusing screen. I used a microfiber cleaning cloth and nikon lens cleaning solution. It was never the same. Once placed back in the camera it was noticeably darker and there were fine scratches on it. I ended up buying a new screen to correct the problem. When they say not to touch the screen they mean it. I recommend just using an air blower.
Sorry, didn't see your post. Are you sure the darkening wasn't because of the solution used? I don't know, I might just wipe it with a brush then.
03-11-2012, 06:11 PM   #6
Forum Member
KansasPen's Avatar

Join Date: Apr 2011
Location: Kansas
Photos: Gallery | Albums
Posts: 73
QuoteOriginally posted by kcobain1992 Quote
Well have you personally ruined any focusing screen by touching it? Because I know of people who cut ME Super screens down to size for their DSLRs, and that kind of behaviour would most likely harm them more than a cotton swab. But I have a little fear too, so that's the reason why I'm asking.


Sorry, didn't see your post. Are you sure the darkening wasn't because of the solution used? I don't know, I might just wipe it with a brush then.
Yes I ruined it with a microfiber cloth. Safe for LCD tvs, lenses and the like. Ruined my focusing screen. Probably less abrasive then a cotton swab and lint free even a microfiber cloth wouldn't do it.
03-11-2012, 06:17 PM   #7
Forum Member
KansasPen's Avatar

Join Date: Apr 2011
Location: Kansas
Photos: Gallery | Albums
Posts: 73
I wouldn't think the solution would be the culprit since it's designed for camera lenses specifically. The focusing screen is just so delicate as previously stated by another poster.
03-12-2012, 06:18 AM   #8
Veteran Member
Philoslothical's Avatar

Join Date: May 2011
Posts: 1,723
I've been thinking about this, as I'm going to be experimenting with a couple different screens soon. With the disclaimer that I haven't done this yet and don't take any responsibility if you do, I think a safe way to do it would be to put the screen in a small plastic bottle of distilled water and gently shake the whole bottle. Theoretically, only the edges of the screen will come into contact with the bottle, but the friction of the distilled water should help significantly to clean it. Distilled water on its own is quite a good solvent, and would definitely be safe for plastics like this.

03-12-2012, 08:03 AM   #9
Veteran Member




Join Date: Nov 2009
Location: Iowa
Photos: Albums
Posts: 2,269
I haven't personally done it, but from what I've read some use distilled water and a tiny bit of dishwashing liquid, followed by a couple of distilled water rinses, followed by a hair dryer (being careful you don't blow the screen away in the process) to dry the thing. This seems like a pretty safe method to me.
03-12-2012, 09:23 AM   #10
Site Supporter
Spodeworld's Avatar

Join Date: Aug 2011
Location: New Joisey
Photos: Gallery | Albums
Posts: 1,240
I've heard about the dishwashing soap and distilled water route, but as noted, use a dryer afterward. A Giotto blow dryer would work. You want to use a drying aid instead of just letting it air dry as that alone might leave streaks. And, you don't want to apply any fibers to wipe it off, as they may scratch the surface.
03-13-2012, 01:15 AM   #11
Veteran Member
kcobain1992's Avatar

Join Date: Dec 2010
Location: Bucharest, Romania
Photos: Gallery
Posts: 1,409
Original Poster
Nice, I might give it a try as soon as someone reports success with this method
03-13-2012, 01:35 AM   #12
Site Supporter
altopiet's Avatar

Join Date: Sep 2010
Location: The Great Karoo, South Africa
Photos: Gallery | Albums
Posts: 1,927
I've learned to live with a “not perfectly clean” screen, as I live in a place where I'll most probably have to clean the screen every week, because of all the dust. If you really have to, I would suggest reading this link Focus Screen and Lens Cleaning Tips, Any Comments - Photo.net Pentax Forum. If I do decide to clean mine, I would do it as explained in the link

Last edited by altopiet; 03-13-2012 at 08:16 AM.
03-13-2012, 08:01 AM   #13
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,483
QuoteOriginally posted by altopiet Quote
I've learned to live with a “not perfectly clean” screen, as I live in a place where I'll most probably have to clean the screen every week, because of all the dust. If really have to, I would suggest reading this link Focus Screen and Lens Cleaning Tips, Any Comments - Photo.net Pentax Forum. If I do decide to clean mine, I would do it as explained in the link
Excellent link! Thanks for sharing. The article does a good job of explaining the hazards and gives what appear to be two good solutions as well.


Steve
03-16-2012, 08:51 AM   #14
Senior Member




Join Date: May 2009
Location: Delaware
Posts: 177
The link to the Photonet post on screen cleaning has some good stuff. My experience with trying to clean a focusing screen was that the fresnel surface is very delicate. For lenses, however, I just huff on them and clean with a clean microfiber cloth, never scratched one yet.
03-20-2012, 04:31 AM   #15
Veteran Member
frank's Avatar

Join Date: Nov 2006
Location: Singapore
Photos: Gallery
Posts: 3,202
I've cleaned many focusing screens: both film and digital SLR cameras, never had any problem yet. I always use a strong blower (a big size Giotto Rocket-Air) plus Eclipse fluid and PEC pads combo. The screens I've cleaned so far:
LX/MX/SuperProgram/Z1p/MZ-3/MZ-S, Ds/K10D/K20D/K7/K5...







These work great on cleaning lenses too. Yes, the Eclips and PEC pads aren't cheap, but well worth the cost imo.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
cotton, fluid, mx, screen
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: Katzeye Optics Split-Screen Focusing Screen for K-7 (CONUS) porterHause Sold Items 2 12-07-2010 05:08 PM
Focusing manual lens with OEM focusing screen, is a split screen really needed? skid2964 Pentax Camera and Field Accessories 16 09-17-2010 02:54 PM
ME Super Focusing Screen Replacement. Gashog Pentax Film SLR Discussion 6 04-29-2010 02:05 PM
A way to clean focusing screen dust (K200D) asdf Pentax Camera and Field Accessories 6 03-07-2009 11:18 AM
Clean behind focusing screen - best method? ksignorini Pentax DSLR Discussion 18 05-14-2008 10:57 AM



All times are GMT -7. The time now is 03:27 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top