Go Back   Rangefinderforum.com > Cameras / Gear / Photography > Gearhead Delights > Repair / Camera Care

Repair / Camera Care This is a good place to discuss the care and repair of your photo gear. You can share Do-It-Yourself repair and maintenance, as well as your recommendations for pro repairs. This new forum was created 4/1/07. PLEASE title your thread wisely, so others searching for a certain make of camera or repair person can find your thread easily!

Reply
 
Thread Tools Search this Thread Display Modes

Always put lens cap on: Question re: light leak
Old 03-02-2016   #1
Hjortsberg
Registered User
 
Hjortsberg is offline
Join Date: Jan 2011
Posts: 257
Always put lens cap on: Question re: light leak

M6 developed a light leak. Took it to well known/highly rated Leica repair shop in Los Angeles. Pin spot had developed in film curtain (I think that is the terminology for it)

I was told this will happen if you don't put lens cap on, lens acts as a magnifying glass and makes pin holes in film curtain leading to light leaks.

was told to always put lens cap on in-between pictures to avoid this problem. take lens cap off right before I take photo, I was told.

How do you shoot street photography if you are always to have lens cap on except right before photo?

Am I mis-understanding what the Leica repair guy said?

Thanks in advance,
  Reply With Quote

Old 03-02-2016   #2
benmacphoto
Registered User
 
benmacphoto's Avatar
 
benmacphoto is offline
Join Date: Oct 2007
Location: Philadelphia
Age: 32
Posts: 899
Quote:
Originally Posted by Hjortsberg View Post
How do you shoot street photography if you are always to have lens cap on except right before photo?

Am I mis-understanding what the Leica repair guy said?
I never have a lens cap on while my camera is out.
I hold the camera so it doesn't face the sun while walking around.

Maybe mis understanding what the repair guy said, or they didn't explain it that well.
Just be mindful of where your camera is pointed.
__________________
Instagram

Website
  Reply With Quote

Old 03-02-2016   #3
DNG
Film Friendly
 
DNG's Avatar
 
DNG is offline
Join Date: Jul 2009
Location: Indianapolis, Indiana. USA
Age: 65
Posts: 2,980
You can also just put the palm of hand over the lens....That is what I do, even though I use an X100T or Nikon SLR.... made a habit a while ago when I did shoot RF's
__________________
Nikon F, F2, D200
Yashica A TLR
My Portfolio
  Reply With Quote

Old 03-02-2016   #4
rick oleson
Ancient Wizard
 
rick oleson's Avatar
 
rick oleson is offline
Join Date: Oct 2004
Location: Lexington, KY USA
Age: 66
Posts: 372
It can certainly do that. An f/2 lens is a powerful little solar furnace, and if the lens is aimed at the sun it can burn a hole through the shutter curtain. This is not a theoretical exercise, I have proof:
https://www.flickr.com/photos/262627...otolist-pGHTNS
This was an Exakta that I had lying on its back on the passenger seat of my car as I drove home for about 45 minutes. The shutter was released so the mirror was up, and the lens was set at f/2. You could see worm tracks all over the front of the curtain where the beam had moved as the car turned different directions, but it was going in a straight line long enough to burn through the shutter curtain and very nearly melt through the film. I managed to repair this with a little circle of film-changing bag fabric cut out with a paper punch and glued over the hole in the curtain.

With a Leica, if your lens is collapsible you can do that to put the beam out of focus when not in use, or you can stop the lens down, if you don't want to use a lens cap. All of my (cloth shutter) cameras, if they are on a shelf that can be exposed to the sun, now have the lenses stopped down to f/16 at all times when on the shelf.

(PS: this damage is not instantaneous. It happens when the lens is aimed so that the direct rays of the sun focus on the shutter curtain, and it takes a little time for it to damage the curtain. Normally carrying the camera with the lens uncovered as you walk, it is not likely for this to happen... but you don't want to set it down on its back while you have a picnic in the sun.)
  Reply With Quote

Old 03-02-2016   #5
Hjortsberg
Registered User
 
Hjortsberg is offline
Join Date: Jan 2011
Posts: 257
Why doesn't the light leak show up in every photo of the 36 exp?

It only shows up in some of them.
  Reply With Quote

Old 03-02-2016   #6
ferider
Registered User
 
ferider's Avatar
 
ferider is offline
Join Date: May 2005
Posts: 11,250
It happens.





Easy to patch with "liquid rubber".

Hold the camera lens down, or shade it with your hand. Most dangerous when wide open and at closer focus (less risky when lens is at infinity).

Roland.
  Reply With Quote

Old 03-02-2016   #7
rick oleson
Ancient Wizard
 
rick oleson's Avatar
 
rick oleson is offline
Join Date: Oct 2004
Location: Lexington, KY USA
Age: 66
Posts: 372
It depends on how much light was shining on the hole between exposures. If the hole is in the opening curtain it will leak while the shutter is cocked, if in the closing curtain it will leak when it's released. If you spend a lot of time in the sun between shots it will have a long time to leak light, if you shoot several shots in succession it will leak less because the exposure time is shorter. It will leak more if you carry the camera outdoors between shots than if you shoot the whole roll indoors in one sitting. Many variables, but all come down to that old photography thing - exposure time.
  Reply With Quote

Old 03-02-2016   #8
dtcls100
Registered User
 
dtcls100 is offline
Join Date: Sep 2010
Posts: 462
If you turn the focusing ring away from infinity to a close focus distance, there shouldn't be a need to keep a lens cap on. What you want to avoid is having the sunlight focused on the shutter curtain. Turning the focusing ring to near its minimum focus distance will help make sure that the sun is not focused on your shutter curtain.
  Reply With Quote

Old 03-02-2016   #9
Sarcophilus Harrisii
Brett Rogers
 
Sarcophilus Harrisii is offline
Join Date: Jun 2009
Posts: 2,665
I use a Contax. No lens cap. No problem!
According to Roger Hicks stopping down one's lens on a Leica should help. In the absence of a cap if I had to use a Leica I'd try this.
Cheers
Brett
  Reply With Quote

Old 03-02-2016   #10
jonmanjiro
Moderator
 
jonmanjiro's Avatar
 
jonmanjiro is offline
Join Date: Feb 2007
Location: Yokohama
Posts: 5,313
Quote:
Originally Posted by ferider View Post
Most dangerous when wide open and at closer focus (less risky when lens is at infinity).
Quote:
Originally Posted by dtcls100 View Post
If you turn the focusing ring away from infinity to a close focus distance, there shouldn't be a need to keep a lens cap on.
Interesting! Should we set the lens to infinity or a close focus distance guys?

In bright sun, when not shooting I tend to leave the focus distance set to a few meters and the lens stopped down, but naturally I've never actually tested whether or not this reduces the risk of burning a hole in the shutter curtain. Maybe I've been doing it wrong all along and just didn't know it...
__________________
flickr
Instagram
  Reply With Quote

Old 03-02-2016   #11
jojoman2
Registered User
 
jojoman2 is offline
Join Date: Apr 2015
Posts: 289
I've never had this problem but I haven't been photographing long.. I'll stop the lens down if it's really bright and I'm not taking pictures and point the camera away from the sun when walking around. I'd sooner pay for new curtains once in a while than leave a cap on between pictures
__________________
kingofkodak.com
  Reply With Quote

Old 03-02-2016   #12
Robert Lai
Registered User
 
Robert Lai is offline
Join Date: May 2007
Posts: 1,637
I would think that you need to defocus the sun to minimize the impact of the rays. The defocused rays would spread out over a wider surface area. You achieve this with the minimum focus setting on the lens.

Focusing at infinity would focus the sun's rays into a point onto the curtains. Since the shutter curtains are only a few millimeters away from the film plane, the lens focused at infinity is effectively focused on the shutter curtains too. As the sun is several billion miles away, it is the very definition of a subject at infinity.

You'll easily notice this if you experiment with a magnifying glass and a sheet of paper on a sunny day - just as we used to do in the schoolyard at recess.

I have habitually learned to point the lens down towards the ground if I am walking around uncapped outdoors.
  Reply With Quote

Old 03-03-2016   #13
David Hughes
David Hughes
 
David Hughes's Avatar
 
David Hughes is offline
Join Date: Dec 2007
Posts: 7,507
Hi,

Over time pinholes might develop and the light coming through the lens on to them will fall on the film and you'll get a light blur there.

Keeping the lens cap on stops the light getting there and so on to the film.

The longer the 'exposure' the brighter the blurred spot. So firing several times quickly means no spot due to the short time the film is exposed. A pin hole acts like a f/512 aperture, or some figure and long time exposures are needed for the blob.

Several have mentioned temporary repairs, if you can find the pinhole.

Regards, David
  Reply With Quote

Old 03-03-2016   #14
rick oleson
Ancient Wizard
 
rick oleson's Avatar
 
rick oleson is offline
Join Date: Oct 2004
Location: Lexington, KY USA
Age: 66
Posts: 372
Quote:
Originally Posted by jonmanjiro View Post
Interesting! Should we set the lens to infinity or a close focus distance guys?
Infinity (or near infinity) is the WORST CASE. That is where the rays from the sun are focused down to the smallest spot on the film.

Since the curtain is actually a mm or two forward from the film plane, the worst case for the curtain is when the lens is a little forward from the infinity stop (just how much depends on the camera design) ... so setting a closer distance might not help as much as you'd hope. If you rack the lens all the way to the close focus stop it should help. Stopping it down is better still; and if it's a collapsible lens, collapsing it will make it much safer.

Quote:
Originally Posted by David Hughes View Post

Several have mentioned temporary repairs, if you can find the pinhole.

Regards, David
Finding the hole in the shutter should be easy: if it's caused by the sun there should be visible damage around the hole on the front of the curtain. To find a hole that's too small to see, remove the lens, open the back door and go into a dark room with a strobe. Looking in from the back, place the strobe head into the lens opening (make sure none of it is aimed at your eyes around the edge of the camera) and fire it. Any holes in the curtain, however small, will be instantly visible. Do this both with the shutter wound and released to inspect both curtains.
  Reply With Quote

Old 03-03-2016   #15
ferider
Registered User
 
ferider's Avatar
 
ferider is offline
Join Date: May 2005
Posts: 11,250
Quote:
Originally Posted by dtcls100 View Post
If you turn the focusing ring away from infinity to a close focus distance, there shouldn't be a need to keep a lens cap on. What you want to avoid is having the sunlight focused on the shutter curtain. Turning the focusing ring to near its minimum focus distance will help make sure that the sun is not focused on your shutter curtain.
Careful, see below !

Quote:
Originally Posted by rick oleson View Post
Since the curtain is actually a mm or two forward from the film plane, the worst case for the curtain is when the lens is a little forward from the infinity stop (just how much depends on the camera design) ... so setting a closer distance might not help as much as you'd hope. If you rack the lens all the way to the close focus stop it should help.
This depends on the focal length of course. For a 35mm Leica lens, and a curtains to film distance of 1-2mm, anything below 1.3m focus distance is the most dangerous (647 to 1260mm, to be exact).

Having a 35mm or wider lens at infinity, and stopped down to f8 or more, is actually pretty safe. Just don't point it into the sun for too long.



Roland.
  Reply With Quote

Old 03-03-2016   #16
David Hughes
David Hughes
 
David Hughes's Avatar
 
David Hughes is offline
Join Date: Dec 2007
Posts: 7,507
Hi,

Any and all light coming in through the lens, focussed or not and open or shut aperture blades will get to the pin hole and on to the film. Carrying the camera around without a cap on it means the time between shots is the exposure time. And if the camera is moving around when you carry it then the light will be all over the blinds. Imagine a pinhole camera with an exposure time in minutes or hours...

As for sun burnt blinds, they are few and far between. There was a survey some time ago on RFF.

Regards, David
  Reply With Quote

Old 03-03-2016   #17
Highway 61
Revisited
 
Highway 61's Avatar
 
Highway 61 is offline
Join Date: Apr 2008
Posts: 2,809
It also depends on the material of the shutter curtains used on our old mirrorless RF cameras. Of course the Contax brass blades curtains, the Canon steel foil curtains and the late Nikon titanium foil curtains can't get burnt through by the image of the sun focused on them.

Yet it seems, given the very few examples of Nikon RF cloth curtains now wearing some fixed pinholes (while there are lots of Leica bodies wearing shutter curtains patches out there), that Nikon's special "habutae silk" was more resistant to this than the regular Leica fabric covered with a layer of rubber on the curtains backside to make them light tight.
__________________

  Reply With Quote

Old 03-03-2016   #18
Dwig
Registered User
 
Dwig's Avatar
 
Dwig is offline
Join Date: Oct 2009
Location: Key West, FL, USA
Posts: 1,646
Quote:
Originally Posted by rick oleson View Post
Infinity (or near infinity) is the WORST CASE. That is where the rays from the sun are focused down to the smallest spot on the film.

Since the curtain is actually a mm or two forward from the film plane, the worst case for the curtain is when the lens is a little forward from the infinity stop (just how much depends on the camera design) ... so setting a closer distance might not help as much as you'd hope. ...
Yep. With 50mm lenses and longer, setting the closest distance would be of significant benefit. With wider lenses, focusing closer can help much and may well make matters worse than setting infinity.

One thing that I used to do, back in the day of using RFs with FP shutters, was to carry the camera "backwards". I'd put the strap on my shoulder with the lens facing my body. I usually kept the lens capped, but on occasion I make a few shots without capping the lens.
__________________
----------
Dwig
  Reply With Quote

Old 03-03-2016   #19
David Hughes
David Hughes
 
David Hughes's Avatar
 
David Hughes is offline
Join Date: Dec 2007
Posts: 7,507
Hi,

I am going to try and find some old blind material and see if I can burn it and time it and so on. The only blind I've seen with pin holes looked OK when bought...

Regards, David
  Reply With Quote

Old 03-04-2016   #20
AndersG
Registered User
 
AndersG's Avatar
 
AndersG is offline
Join Date: Dec 2004
Location: Göteborg, Sweden
Age: 41
Posts: 251
With some sun and a bit of time you can get notable results: When "baking"[*] my Jupiter 11 135mm f/4 lens in the autumn sun some years ago I melted a hole in the rear lens cap (a plastic film canister lid) even though it must have been quite far (~10mm?) from the film plane (I don't recall the focus distance set). I won't be doing that again..
[*] Supposedly good for killing off fungus, but must be rather hard on the lubricants in the lens, I guess.
__________________
My Gallery
  Reply With Quote

Old 03-04-2016   #21
leicapixie
Registered User
 
leicapixie is offline
Join Date: Jun 2011
Location: Toronto.Canada
Posts: 1,608
When walking, I mostly de-focus my lens to closest distance.
Finding pinhole easy.
Use a small electronic flash from back.
Try cocked and un-cocked.
Use a black liquid rubber sealant.
A tiny drop!
Oh! My Nikon F has a small pinhole in titanium curtain.
I found and sealed it. with my method.
  Reply With Quote

Old 03-04-2016   #22
rick oleson
Ancient Wizard
 
rick oleson's Avatar
 
rick oleson is offline
Join Date: Oct 2004
Location: Lexington, KY USA
Age: 66
Posts: 372
A little off the subject, but pinholes and burn holes are totally different, unrelated things. Most of the above discussion has been about how to avoid CREATING burn holes (if you really don't think this happens, you obviously have not clicked on the link I posted above. They may be few and far between, but I own one set of them)... not how to avoid letting light get to a hole that's already in the curtain.

Pinholes are not actually holes: they are cracks in the rubber coating of the curtain fabric. Light passing through the cracks gets broken up by the weave of the fabric and looks like separate holes when imaged on the negative. These are most common in shutters from the late 40s and early 50s... pretty common in IIF and IIIF models but I have never encountered them in an M camera.

To repair a burn hole, you can find the hole and patch it. Since pinholes are generally a symptom of an end-of-life problem affecting the entire shutter curtain, patching is at best a temporary fix.
  Reply With Quote

Old 03-05-2016   #23
David Hughes
David Hughes
 
David Hughes's Avatar
 
David Hughes is offline
Join Date: Dec 2007
Posts: 7,507
Hi,

Interesting, thanks.

I had a day out walking around with my camera yesterday and wondered how the sun could get at the blind as the camera was with the lens horizontal 99% of the time and the sun was way up above my head. And putting the camera down it was either horizontal or else tipped forward under the weight of the lens and hood.

As for pin holes, the curtains are rubberised silk or something and before and during the war that would have been pure rubber and not an improved man-made version. So it might be worth pointing out that rubber perishes and light is usually what does it. Nowadays it only happens with elastic bands but I'm sure everyone has seen that happen.

Regards, David
  Reply With Quote

Old 03-06-2016   #24
rick oleson
Ancient Wizard
 
rick oleson's Avatar
 
rick oleson is offline
Join Date: Oct 2004
Location: Lexington, KY USA
Age: 66
Posts: 372
Quote:
Originally Posted by David Hughes View Post
Hi,

Interesting, thanks.

I had a day out walking around with my camera yesterday and wondered how the sun could get at the blind as the camera was with the lens horizontal 99% of the time and the sun was way up above my head.

Regards, David
Try stopping in at a sidewalk cafe on a sunny day at lunch time, and set your camera on its back on the table while you spend half an hour eating lunch. The other 99% of the time won't count for much that afternoon. The point is not whether or not it can happen, of course it can happen; the fact that you've always taken care not to let it happen is to your credit but it doesn't make it impossible. Continue doing as you have been, and you'll have nothing to worry about.

: ) =
  Reply With Quote

Old 03-06-2016   #25
David Hughes
David Hughes
 
David Hughes's Avatar
 
David Hughes is offline
Join Date: Dec 2007
Posts: 7,507
Hi,

In that situation I'd be more worried about the waiter spilling food or drink on to it. And it's more likely to happen...

Regards, David
  Reply With Quote

Old 03-07-2016   #26
rick oleson
Ancient Wizard
 
rick oleson's Avatar
 
rick oleson is offline
Join Date: Oct 2004
Location: Lexington, KY USA
Age: 66
Posts: 372
I'll just await the results of your experiment then. Good luck!

: ) =
  Reply With Quote

Old 03-07-2016   #27
B-9
Devin Bro
 
B-9's Avatar
 
B-9 is offline
Join Date: Jul 2009
Location: Michigan
Posts: 2,273
Like many others,

I've made a habit of covering the lens with my palm, or holding the camera in my hand pointing towards the ground.

It's not something I think about much, but when I do, I feel silly covering the lens on my M8 with its metal curtains.
__________________
Made in Michigan

RangefinderGuy @ Instagram
  Reply With Quote

Old 03-07-2016   #28
Gregm61
Registered User
 
Gregm61 is offline
Join Date: Jan 2015
Posts: 474
Cloth shutters = problem if you point them at the sun, and it's easily done even just walking around with your camera over the shoulder if it happens to be pointing in the right direction.

I've always been very aware of where the sun is when using/carrying my mechanical Leicas, either the M6 or M4, but I never walk around with the lens cap on. When actively shooting I'll often be pointing the camera down, whether its around my neck via the strap and I am holding the camera in my right hand, or just have the camera strap around my wrist and camera in-hand. I rarely even put the cap on when placing the camera in the bag.

The digital M's solve the whole issue with their metal shutters, latest of which (M262) are very quiet in use, much like the film M's.
  Reply With Quote

Old 03-07-2016   #29
David Hughes
David Hughes
 
David Hughes's Avatar
 
David Hughes is offline
Join Date: Dec 2007
Posts: 7,507
Hi,

Well, I was thinking about it this afternoon, the only people who put cameras out in the sun tilted upwards a little are naughty dealers with those little display stands...

Regards, David
  Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 16:19.


vBulletin skin developed by: eXtremepixels
Powered by vBulletin® Version 3.6.8
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.

All content on this site is Copyright Protected and owned by its respective owner. You may link to content on this site but you may not reproduce any of it in whole or part without written consent from its owner.