FA 31mm Limited: filters touching front element?

baj · 04-10-2012, 10:27 AM

I saw a reference (in a video) to the fact that the glass in some filters can actually touch the convex front element on the FA 31mm LTD. I'd be curious to know if anyone here has run into this problem, and which brands/mounts of filters work or don't work with this lens. Is it just a matter of thin filter rings vs. the traditional thicker style, or is it not that simple? The video said that the Hoya HMC and S-HMC filters are ok, but I think the rings for at least some of those filters may have changed in recent years and I don't know exactly which ones they were talking about (e.g. HMC UV(0) thick frame vs. HMC UV(C) thin frame).

Zav · 04-10-2012, 10:50 AM

Never heard such a thing and I have used thin frame Hoya filter with my 31mm.

ElJamoquio · 04-10-2012, 11:46 AM

It certainly is close. I've never seen it actually happen but of course I only have a couple of filters.

I keep a filter on this lens just to put a lens cap on it.

Laurentiu Cristofor · 04-10-2012, 03:39 PM

Originally posted by Zav

Never heard such a thing and I have used thin frame Hoya filter with my 31mm.

Never heard of such issue either. I use a regular (not thin) B+W filter.

sjwaldron · 04-10-2012, 03:56 PM

It was probably my video, and yes... some filters that don't have a decent sized gap in the back will touch the lens.

However, I have a Hoya S-HMC UV(0) filter on the lens and it works fine.

Edit: Ones that cause an issue for me:
Tiffen Digital Ultra Clear I bought for the 31mm (terrible filter with no coating as well)
Canon UV filter I bought a long time before the 31mm
Vivitar UV filter I bought in the Caribbean

sjwaldron · 04-10-2012, 04:47 PM

I spent a few minutes taking a photo with the worst filter on the lens so there isn't any argument about it.

Can't say I like putting that thing on my lens though...

Nick Siebers · 04-10-2012, 04:49 PM

I tried to put a 58mm pinch cap on mine, and scratched the front coating. :-(

wlachan · 04-10-2012, 04:52 PM

Just put a metal hood on it and forget any cap. TIFFEN filters? Avoid at all cost.

frank · 04-10-2012, 05:45 PM

Originally posted by Nick Siebers

I tried to put a 58mm pinch cap on mine, and scratched the front coating. :-(

A 49mm pinch cap scratched my FA77

Won't use those caps w/o a hood on. Now I have hoods permanently on three of my FA Limiteds.

Laurentiu Cristofor · 04-10-2012, 06:10 PM

Originally posted by Nick Siebers

I tried to put a 58mm pinch cap on mine, and scratched the front coating. :-(

That can happen. Pinch caps are not hollow on their back, so that plastic can scratch against the front element. I received a used lens with a cap like that, but fortunately, it didn't get scratched and I replaced the cap.

Also, are you sure your coating is really scratched? It may be that the plastic left a mark looking like a scratch, but it may go away if you clean it. I had marks like this on a lens (I forgot which) and I thought they were scratches, but they went away after wiping them with a microfiber. SMC coatings are pretty resistant to scratches.

Nick Siebers · 04-10-2012, 07:14 PM

Originally posted by Laurentiu Cristofor

Also, are you sure your coating is really scratched? It may be that the plastic left a mark looking like a scratch, but it may go away if you clean it. I had marks like this on a lens (I forgot which) and I thought they were scratches, but they went away after wiping them with a microfiber. SMC coatings are pretty resistant to scratches.

Oh I cleaned it, about 100 times. It was scratched alright. And with surprisingly little pressure. I think that alone soured me on the lens, it made me nervous to use it for fear of damaging it more. Finally I sold it (marked down for the scratch, of course) and got something cheaper.

Zav · 04-14-2012, 08:42 AM

Originally posted by wlachan

tiffen filters? Avoid at all cost.

that.

Docrwm · 04-14-2012, 08:58 AM

Originally posted by sjwaldron

I spent a few minutes taking a photo with the worst filter on the lens so there isn't any argument about it.

Can't say I like putting that thing on my lens though...

I saw your video too, thanks for the nice work showing off Pentax gear. I've had too many issues with Tiffen gear myself to buy any more of it.

Docrwm · 04-14-2012, 09:00 AM

Originally posted by frank

A 49mm pinch cap scratched my FA77

Won't use those caps w/o a hood on. Now I have hoods permanently on three of my FA Limiteds.

Hadn't considered the sharp corners I see on the plastic elements on the interior of pinch caps until your post. Hmmm, perhaps its time to buy different caps.

Sandy Hancock · 04-14-2012, 08:37 PM

I suspect there is a reason Pentax use such quirky lens hoods and caps for their limited lenses. Apart from their individualistic appeal, they may actually be properly engineered for the purpose....

04-10-2012, 10:27 AM	#1
baj Junior Member Join Date: Mar 2011 Photos: Gallery Posts: 43	FA 31mm Limited: filters touching front element? I saw a reference (in a video) to the fact that the glass in some filters can actually touch the convex front element on the FA 31mm LTD. I'd be curious to know if anyone here has run into this problem, and which brands/mounts of filters work or don't work with this lens. Is it just a matter of thin filter rings vs. the traditional thicker style, or is it not that simple? The video said that the Hoya HMC and S-HMC filters are ok, but I think the rings for at least some of those filters may have changed in recent years and I don't know exactly which ones they were talking about (e.g. HMC UV(0) thick frame vs. HMC UV(C) thin frame).

04-10-2012, 03:56 PM	#5
sjwaldron Veteran Member Join Date: Aug 2009 Photos: Gallery Posts: 1,235	It was probably my video, and yes... some filters that don't have a decent sized gap in the back will touch the lens. However, I have a Hoya S-HMC UV(0) filter on the lens and it works fine. Edit: Ones that cause an issue for me: Tiffen Digital Ultra Clear I bought for the 31mm (terrible filter with no coating as well) Canon UV filter I bought a long time before the 31mm Vivitar UV filter I bought in the Caribbean Last edited by sjwaldron; 04-10-2012 at 04:09 PM.

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04-10-2012, 10:50 AM	#2
Zav Pentaxian Join Date: Feb 2009 Photos: Gallery Posts: 1,371	Never heard such a thing and I have used thin frame Hoya filter with my 31mm.

04-10-2012, 11:46 AM	#3
ElJamoquio Veteran Member Join Date: Feb 2011 Posts: 4,873	It certainly is close. I've never seen it actually happen but of course I only have a couple of filters. I keep a filter on this lens just to put a lens cap on it.

04-10-2012, 03:39 PM	#4
Laurentiu Cristofor Banned Join Date: Nov 2009 Location: WA Photos: Albums Posts: 3,055	Originally posted by Zav Never heard such a thing and I have used thin frame Hoya filter with my 31mm. Never heard of such issue either. I use a regular (not thin) B+W filter.

04-10-2012, 04:47 PM	#6
sjwaldron Veteran Member Join Date: Aug 2009 Photos: Gallery Posts: 1,235	I spent a few minutes taking a photo with the worst filter on the lens so there isn't any argument about it. Can't say I like putting that thing on my lens though...

04-10-2012, 04:49 PM	#7
Nick Siebers Veteran Member Join Date: Jun 2008 Location: Madison, WI Photos: Gallery \| Albums Posts: 2,165	I tried to put a 58mm pinch cap on mine, and scratched the front coating. :-(

04-10-2012, 04:52 PM	#8
wlachan Veteran Member Join Date: Sep 2006 Location: Canada Photos: Albums Posts: 2,625	Just put a metal hood on it and forget any cap. TIFFEN filters? Avoid at all cost.

04-10-2012, 05:45 PM	#9
frank Veteran Member Join Date: Nov 2006 Location: Singapore Photos: Gallery Posts: 3,202	Originally posted by Nick Siebers I tried to put a 58mm pinch cap on mine, and scratched the front coating. :-( A 49mm pinch cap scratched my FA77 Won't use those caps w/o a hood on. Now I have hoods permanently on three of my FA Limiteds.

04-10-2012, 06:10 PM	#10
Laurentiu Cristofor Banned Join Date: Nov 2009 Location: WA Photos: Albums Posts: 3,055	Originally posted by Nick Siebers I tried to put a 58mm pinch cap on mine, and scratched the front coating. :-( That can happen. Pinch caps are not hollow on their back, so that plastic can scratch against the front element. I received a used lens with a cap like that, but fortunately, it didn't get scratched and I replaced the cap. Also, are you sure your coating is really scratched? It may be that the plastic left a mark looking like a scratch, but it may go away if you clean it. I had marks like this on a lens (I forgot which) and I thought they were scratches, but they went away after wiping them with a microfiber. SMC coatings are pretty resistant to scratches.

04-10-2012, 07:14 PM	#11
Nick Siebers Veteran Member Join Date: Jun 2008 Location: Madison, WI Photos: Gallery \| Albums Posts: 2,165	Originally posted by Laurentiu Cristofor Also, are you sure your coating is really scratched? It may be that the plastic left a mark looking like a scratch, but it may go away if you clean it. I had marks like this on a lens (I forgot which) and I thought they were scratches, but they went away after wiping them with a microfiber. SMC coatings are pretty resistant to scratches. Oh I cleaned it, about 100 times. It was scratched alright. And with surprisingly little pressure. I think that alone soured me on the lens, it made me nervous to use it for fear of damaging it more. Finally I sold it (marked down for the scratch, of course) and got something cheaper.

04-14-2012, 08:42 AM	#12
Zav Pentaxian Join Date: Feb 2009 Photos: Gallery Posts: 1,371	Originally posted by wlachan tiffen filters? Avoid at all cost. that.

04-14-2012, 08:58 AM	#13
Docrwm Veteran Member Join Date: Sep 2010 Location: Somewhere in the Southern US Photos: Gallery \| Albums Posts: 12,285	Originally posted by sjwaldron I spent a few minutes taking a photo with the worst filter on the lens so there isn't any argument about it. Can't say I like putting that thing on my lens though... I saw your video too, thanks for the nice work showing off Pentax gear. I've had too many issues with Tiffen gear myself to buy any more of it.

04-14-2012, 09:00 AM	#14
Docrwm Veteran Member Join Date: Sep 2010 Location: Somewhere in the Southern US Photos: Gallery \| Albums Posts: 12,285	Originally posted by frank A 49mm pinch cap scratched my FA77 Won't use those caps w/o a hood on. Now I have hoods permanently on three of my FA Limiteds. Hadn't considered the sharp corners I see on the plastic elements on the interior of pinch caps until your post. Hmmm, perhaps its time to buy different caps.

04-14-2012, 08:37 PM	#15
Sandy Hancock Moderator Site Supporter Join Date: Feb 2012 Location: Adelaide Hills, South Australia Photos: Gallery \| Albums Posts: 11,272	I suspect there is a reason Pentax use such quirky lens hoods and caps for their limited lenses. Apart from their individualistic appeal, they may actually be properly engineered for the purpose....