koni-omega filters

<p>I want to use filters on my Koni-Omega lenses and don't know what size to use. I have a 90mm now and hope to get the other 2. How do you put filters on them? There are no threads on the 90mm and the hood is in the way.</p>

<p>On my Koni Omega 90mm there is/was a threaded ring inside the front of the lens it is Series VI I believe.<br /> If you remove that threaded ring the threads inside the front of the lens that remain are 49mm allowing me to use 49mm filters.</p>

<p>The threaded ring was a little tricky to remove as it was very tight and you need to be careful not to scratch the front of the lens.</p>

<p>Martin is quite right about where the threads are. He's right, too, about the fact that the filters are Series filters, in this case Series VI. But the OP might not be familiar with Series filters. These are unthreaded filters that are held in place by a threaded and glassless ring. They're readily available on auction sites and from classic camera dealers, for not very much money. If the ring is tight, it can easily and safely be moved using the kind of flexible rubber strip that is marketed for opening jamjars.<br>

I have a feeling, though, that Martin is wrong about the fit of 49mm. As far as I recall, the thread diameter is 44mm. I believe the pitch of the thread of Series filters is different, too, so while you can start a threaded filter off, it soon jams and you then risk stripping the threads of your filter or - much worse - the threads of your lens. If you can't find the proper thing, then firms like Tiffen make adapters that do the job properly. If you use an adapter, though, make sure it's a step-up adapter (i.e. to a filter of larger size than Series VI) otherwise you risk vignetting.</p>

<p>On my Rapid Omega 100 90mm lens, after the series filter adapter is removed, the underneath thread is definitely 49mm. ( http://www.photo.net/classic-cameras-forum/00YatJ ). The adapter ring is a 49>Series VI.</p>

<p>Use a rubber pad or such to remove the series filter, being very careful, as Martin says, not to scratch the front element of the lens.</p>

<p>"If you remove that threaded ring the threads inside the front of the lens that remain are 49mm allowing me to use 49mm filters."<br>

How does the front element stay in if you remove the retaining ring? You use standard 49mm filters? That would be my preference since I have those already. If I go with Series VI that still requires removal of the retaining ring? You'd think K-O would have made better provisions for filter use.</p>

<p>Just checked my 90mm lens and it is definitely 49mm thread once the threaded ring is removed.</p>

 

<blockquote>

<p>How does the front element stay in if you remove the retaining ring? You use standard 49mm filters?</p>

</blockquote>

<p>The ring I am talking about does not hold the front elements in, I believe you would have to remove the lens name and size info plate to get that far. Yes, I use standard 49mm filters and the nice thing is the lens hood still pulls out which would not be the case if you used a Series VI step up to 52 or 55mm.</p>

<p>BTW, just in case you ever get the 58mm (60mm) lens I use 55mm filters in it as I found a Series VII to 55mm step up and the hood still works.</p>

<p>Good luck.</p>

<p>"How does the front element stay in if you remove the retaining ring?"</p>

<p>It's clear that, if you need to ask this question, you don't understand what you're talking about, and so you're making an uninformed criticism. The retaining ring retains the filter, not the front element. I don't know the rationale for Series filters. I do know that they were used a lot in the film industry. I also know that they were used extensively by Leitz, who make what are acknowledged by many to be the world's finest camera lenses. So K-O can't have been completely wide of the mark.</p>

<p>I just remembered how I got the threaded ring in question off the front of the lens.<br>

I got a rubber bung or stopper from the hardware store, about 1 1/2 to 2 inches in diameter.<br>

I then used this to push against the ring and twist it. This trick is recommended on other sites across the internet so not my original idea. It is harder to describe it than to do it; but, once again care is needed. I am pretty ham-fisted and I did not break or scratch anything.</p>

<p>Series type filters were very popular a while back.<br>

The main reason being that filters were expensive so using the same filter on multiple lenses by just changing the Series adapter ring lowered the cost and saved having to buy the same filters in different sizes.</p>

<p> </p>

<p>A large rubber "cork" (aka bung or stopper) is best if you can find one big enough, otherwise you can use the rubber pad with a wood backer or some such. Be sure that you still have the Series VI mount on the camera before you "take it off". ;) It should obscure some of the lettering on the front of the lens, shown in the picture below.</p>

<p>Here's the assembly - note that the so-called "retaining" ring is essentially a 49mm>Series VI stepdown adapter. The silver part is what you need to hold in the unthreaded series filters.</p>

<p>I do not have the original lens hood referred to above, but a regular 49mm screw in hood works just fine.</p><div></div>

<p>"It's clear that, if you need to ask this question, you don't understand what you're talking about, and so you're making an uninformed criticism."<br>

Everyone else seems to be able to discuss this without being an obnoxious ahole, why can't you? Upon closer inspection I see it's not a retaining ring for the front element as I had assumed but for Series filters. I successfully removed it and fit my 49mm filter. Thanks for all the other helpful responses.</p>

<p>I was able to remove the ring pretty easily with my thumbs. What size filter threads does the 180 use? And where can I get the front gasket or can I make it from some kind of material?</p>

<p>I don't have the 180 lens but I am almost certain it takes Series VIII (8) filters, so if you can find a Series 8 adapter to a regular filter size it would work. I also think the quite rare 135mm lens takes Series 8 filters too. Just make sure you find one the right way around as in Series VIII to XXmm probably 58mm or 62mm as you will see lots for sale that are the other way around.</p>

<p>Can't help much much on the gasket part but I know there is a guy called Greg Weber that is an expert Koni repair person so he may have one he will sell you or give advice. Do a search for Koni and Greg Weber and you will find him.</p>

 

<p>I have the 58mm lens and am trying to locate a series VII step up to 55mm adapter . I got one off of the auction site, but for some reason a 55mm filter screws in just a tad and then stops. I searched for a adapter and all that shows are 55mm to series VII adapters - opposite of what I need. I've had my rapid Omega 2 weeks and so far am enjoying it ! Thanks for any response- I know this is an old thread -- tom</p>

<p>Yes, this is an old thread!</p>

<p>I I have no idea why the adapter you got is giving you problems; but as to finding a Series 7 to 55mm the can be difficult to find.<br /> Many times they are list wrong and are 55mm to Series 7.<br /> There are some on ebay right now that Series 7 to 55mm even some labelled backwards in the title.</p>

<p>The key is to look for ones marked Series VII -> 55mm or Series VII/55 or Series 7/55mm and so on.</p>

<p>Here's one that appears to be correct even though the seller listed it incorrectly...<br /> http://www.ebay.com/itm/Camera-Lens-Adapter-Ring-55mm-to-Series-VII-Series-7-Step-Down-Ring-/191216143299?pt=US_Filter_Rings_Holders&hash=item2c855ecbc3<br /> I have no affiliation with the seller.</p>

<p>Hello Martin, Thanks for your reply. I looked at the one on ebay and think I'll give it a try. I've been going around in circles and hopefully this gets me straighten out . thanks again !!</p>

<p>Good luck.</p>

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