Seeking advice on stuck and dented filter ring

[eastwestdivide]

Thanks to dropping my DSLR lens-first onto carpet (the camera strap got caught on a drawer knob), I've now got a filter ring stuck fast on the end of the lens. When it fell, the lens cap was forced into the opening, smashing the glass of the filter, but thankfully the lens itself and the camera are both undamaged.

However, the filter ring, now glass-free, won't budge, and either the filter ring or possibly the corresponding threaded front of the lens appears to be dented at one point, making it likely that I'll make a bigger mess trying to remove it.

I'm thinking to just get another filter and screw it into the front, hoping that it doesn't protrude so far as to vignette the shots at the wide end of the zoom.

Any thoughts or advice gratefully received.

[Rumblestripe]

Personally, I think I'd try to cut it off. In simple terms you now have a threaded "O" ring attached to the front of your lens, if you crush the ring inwards at a single point it shouldn't distort the lens... Of course that's easy to say when it isn't my lens on the operating table! Whether I'd have the bottle to try this on one of my own lenses...

 

Of course it may be the fall has already distorted the thread on the front of your lens? You won't know until you get the remaining ring off! If it is a zoom lens you are almost guaranteed to get some vignetting at the wide end with a second filter added...

 

Dunno, your call really! Good luck!

[beast66606]

I used a pair of Xurons and wittled away at a piece of the filter ring, trying to bend it inwards, until I'd done enough and the ring came away

[eastwestdivide]

Thanks for the advice people. Found the instruction booklet, which does say two filters = vignetting, so it's a choice between brute force and ignorance (aka delicate surgery) or no filter and hope for no more accidents. Third option: sit and think about it...

[beast66606]

Remember you've only got one filter, mounted further out (if you try the screw into the existing filter, no glass just the thread, approach), so vignetting is not a done thing.

 

The one I damaged came off easily enough, just took time, and it was quite bad in the "Oops Scotties" stakes, but it will be down to luck as to how much of the threads are damaged and therefore how much they are trapped together.

[Steve Taylor]

mmm not wishing to be a party-pooper, but before trying this check that the lens is still "true" and doesn't need the attentions of a service agent. IIRC the science part of this from college many moons ago, mount the lens onto the camera and using a tripod (copy stand, studio stand etcetcetc), set up as near to perfectly parallel to a flat surface onto which you place something like a grid patterned piece of paper. Starting with mid aperture take a photo and at maximum zoom in an appropriate browser/editing app assess whether the lens is focusing evenly across the image field. If an element has shifted (for example if the barrel is distorted) it will be noticeable that an area is out of focus. If this is acceptable repeat at both wider and narrower apertures to get an idea of how the lens is behaving (this changes the depth of field and hence apparent sharpness). If there is any hint of a problem and you go for a repair leave the filter remains in place and let the repair centre handle it - therefore its there problem if the front element gets damaged during removal.

 

Ps - if you opt to remove make a number of closely spaced "slits/notches" allowing you to grip a part and bend it inwards releasing the tension that is holding the ring in place

[eastwestdivide]

Thanks again people - the vignetting is specifically mentioned in the instructions if you put two filters on, but it would be worth testing to see if they're just playing safe with the instructions.

And I'll definitely do some tripod tests. Everything moves smoothly on the lens, but yes, I hadn't considered that a small shift in something non-moving could well cause problems with the results.

[Katier]

Is it the kit lens? If so they aren't expensive, especially second hand, as their new price is effectively only around £50.

[shortliner]

Have you tried on of the Jar lid removers - like a solid rubber strap on a handle that you wrap around the lid and move the handle in the direction of unscrewing - whilst doing so the band gets tighter - it is surprising how much added grip and traction this will give - and may be enough to get the ring to unscrew

[eastwestdivide]

Shortliner - thanks, yes, already tried one of those up to the point where I lost my nerve due to the force being applied by my other hand to the rest of the lens. It's tricky to keep the wide band of rubber on the narrow band of filter without also gripping the end of the lens, and was also worried about the point of leverage of the handle causing worse damage.

Katier - no, it's not the kit lens, it's a nice Sigma - £50 would be great, only the price of a couple of good filters!

[beast66606]

Thanks again people - the vignetting is specifically mentioned in the instructions if you put two filters on,

 

Yes but it assumes they both have glass ! - you mention your stuck one is broken ...

[Katier]

Won't be the glass that causes the vignetting it'll be the extended cylinder caused by a second filter that causes it.

[eastwestdivide]

Are we talking about the same thing with the word vignetting? I thought it meant what Katier said above - the black edge of the second filter intruding slightly into the corners of the frame at the wide end of the zoom.

Looking it up, it means reduction in brightness at the periphery, so maybe I needed a different word. Whatever the meaning, I won't really know if it's a problem until I try it with two filters (one glass-less).

Thanks again.

[54Strat]

This happened recently to me when I dropped my sigma 10-20. The filter smashed but left a slight dent in the mount and as a result wouldn't budge when I tried to remove it.

 

So wearing marigolds didn't work, and I wasn't prepared to cut it off. I ended up using two sets of angled pliers, and slowly exerted rotational force from opposite sides, whilst holding the camera between my knees. That and a bit of bravery did the trick.

 

Paul

[Katier]

Are we talking about the same thing with the word vignetting? I thought it meant what Katier said above - the black edge of the second filter intruding slightly into the corners of the frame at the wide end of the zoom.

Looking it up, it means reduction in brightness at the periphery, so maybe I needed a different word. Whatever the meaning, I won't really know if it's a problem until I try it with two filters (one glass-less).

Thanks again.

 

Exactly - vignetting IS reduction in brightness often caused by the edge of the lens circle causing a reduction in light into the edges of the image.

[trisonic]

I've often used two filters at once on my Wife's Nikon system with no issues - I thought "vignetting" meant something else caused by optical distortion?

 

Best, Pete.

[emac]

I removed a stuborn filter by puting a hot cloth round the filter and then used a jar lid opener worked okay but I had not droped the camera.

I did drop my cannon 7d with a 15-85mm is lens which landed lens hood first on a carpeted floor thought it was ok but image stabiliser did not work had both camera and lens checked out ; camera okay but lens needed a new iris unit which resulted in a bill for £135 whould recommend a wee checkup and maybe repairer could remove filter.

[colin penfold]

I dropped my pentax out of my rucksack while it was on my back (!) onto a pavement. My filter glass smashed and the filter frame dented to the extent that it would no longer rotate in the lens mounting. I removed all the broken glass and put a pad of tissue into the void to protect the lens glass. I then cut a break into the ring of the filter where it was dented (using xurons as someone else did above)

 

I was then able to gently bend the distorted part of the filter frame inwards until only undistorted thread was in contact with the mounting thread on the lens. I was then able to twist the filter and safely remove it. Heart in mouth stuff. Go steady and it can be done!

[eastwestdivide]

Thanks again for the various comments, experience and advice. Took a few test shots last night and it does look like the focussing is wrong on one side of the image now, as per twa_dogs' post earlier, so it's more serious than first thought.

Will leave things as they are until I can get some repair quotes.

 

How do you type a swearing smiley face?

[gordon s]

Might be worth checking your house contents or travel insurance to see if the repair is covered.

[Katier]

I've often used two filters at once on my Wife's Nikon system with no issues - I thought "vignetting" meant something else caused by optical distortion?

 

Best, Pete.

 

You might be thinking of CA (don't ask me to spell it ) which is a very different thing.