View Full Version : Sticking darkslide

27-Aug-2017, 13:31
I was out in Undercliffe Cemetery, Bradford, yesterday and had the darkslide stick on me twice with two different 10x8 film holders.
I really had to give them a pretty severe tug to get them to shift and the whole process didn't help with stability etc.
Any ideas what it could be and how to solve it? The film holders appear flat and true, i.e. not warped, and the only thing I can think of is damp as I had them loaded for around a week and kept in the basement as it's cooler down there.
Once I had made the exposures the slides slotted back in as free and easy as you like!

For anyone interested:

“Undercliffe Cemetery is the zenith of England’s cemeteries...it is an enigmatic place and it does fill one with the awe you would expect a Victorian cemetery to fill you with.”
Dr Julien Litton
Leicester University


27-Aug-2017, 13:52
Might have been the combination of a little moisture, a little dirt/grime in the channels, and a little time.

Some furniture polish on the darkslides will keep them slippery.

You might want to take a old tooth brush or something similar and clean out the channels the darkslides run in inside the holder, followed by a nice dusting.

27-Aug-2017, 14:10
Thanks Vaughn, I'll give that a go when I unload the films

27-Aug-2017, 14:39
Might have been the combination of a little moisture, a little dirt/grime in the channels, and a little time.

Some furniture polish on the darkslides will keep them slippery.

You might want to take a old tooth brush or something similar and clean out the channels the darkslides run in inside the holder, followed by a nice dusting.

Piggy-backing on Vaughn's perfect advice, I have used, sparingly, Armor All to clean. Sparingly is the clue. Wipe it off and the remaining molecular layer works for us. Don't use it in the grooves. Vaughn's toothbrush is good.

Aside: I am now experimenting with something called Top Coat F11 which is amazing on computer screens and on my vehicle. Google it!

Nodda Duma
27-Aug-2017, 18:23
I've used beeswax to help very old dark slides work better. All natural!

Jerry Bodine
27-Aug-2017, 20:22
After you've cleaned your holder(s) I can recommend a very good product for the darkslides that I use. I get it from a nearby store here in the Seattle area, but googling I see it can be had through Amazon so it may be available to UK as well although shipping may kill the deal. It's called Kleenmaster Brillianize. Here's the link to my source for additional info about its uses:


I initially bought it for use on acrylic "glazing" for my framed photos. Then I recommended it to a forum member who was experiencing static electricity marks on negatives made in the colder/drier air in Death Valley and solved the problem. It makes the darkslides slicker as well. I think it's worth a try if you can handle the shipping cost.

Eric Leppanen
27-Aug-2017, 20:37
I second the nomination of Brillianize. It reportedly was recommended years ago by John Sexton, see http://www.largeformatphotography.info/forum/showthread.php?2218-Cleaning-Darkslide.

30-Aug-2017, 15:19
Developed the three exposures I made and unfortunately one appears to have suffered some light leakage. This is possibly from me struggling to get out the dark-slide as I number all my holders and I've never had the problem before. Sad really as it was my best composition of the day but I guess that's always the case :(
Hopefully I will get some good light this weekend and go back to try the shot again
As the holders are now empty I tried the furniture polish idea as it is readily available. Hopefully that will cure things.


30-Aug-2017, 17:36
Use bee's wax from your local bee keeper or (second choice) parafin from your grocery store. Gently move each of the two the long thin edges of a dark slide one time down the block of wax.

Of course, you do not want to wax the short edge of the dark slide because that comes into contact with the felt light trap so could contaminate it over time.

30-Aug-2017, 17:37
What about using surf board wax or snow ski wax?

30-Aug-2017, 20:04
If it just the slide, the above tips can work, but if it is a plastic slide, sometimes it's an old layer of sticky gunk on it from tobacco smoke etc, so try washing them with dishwashing liquid well, and leave a trace of the detergent on them to avoid a static build-up charge...

But more likely is that the holder slide guides can have old crud in them, or be swollen or warped... You can check this by inserting/removing the slides one at a time and note if there is any points that have greater resistance while you do this... If they are old wood holders, this is more likely, but you might try to dehumidify the wood holders, maybe by leaving them in a cold oven (that has a pilot light) for a few days so the slight heat inside will start to dry them out, and try again with the slides... (Don't forget to pull them before baking a pizza or pie!!!)

The last trouble spot is if the velvet or wool in the light trap is bunching up and binding the slide, so check for that... Sometimes there is corrosion on the metal that covers the light trap on non-plastic holders that can bind the slides, but you can usually hear grinding when you move the slides, and there can be debris or scratching on the slide...

See if you can isolate the issue, and post what you might find here for specfic solution input...

Good Luck!!!

Steve K

30-Aug-2017, 20:15
Not all waxes are slippery! I like floor wax or Renaissance Wax. Both go on thin and are slippery. The difference is huge, and so I also wax my holders, which makes them much easier to insert and remove.

Peter Collins
31-Aug-2017, 04:29
I don't agree with Nodda Duma. Having been a beekeeper I know beeswax is actually quite sticky. I would rather use either soap or paraffin on the edges, very lightly, leaving no visible residue--i.e., wipe clean after application.

31-Aug-2017, 05:05
Using silicone spray on a cloth and wiping the edges of the slide may help.
Old trick used for decades is to wipe edges with wax paper. Slide back & forth like polishing the slides.

Jim Noel
31-Aug-2017, 13:17
Nose grease. Nothing works better. Apply it just along the edges of the dark slide.

31-Aug-2017, 16:11
Well I revisited Undercliffe Cemetery early today to retake the shot that was spoiled, presumably, by me tugging at the stuck darkslide and using the same film holder that I had originally used and which I 'lubricated' with furniture polish.
Happy to say that all went well and the film developed nicely with no light leak stains