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Patrick Dixon
17-Apr-2009, 11:27
I'm new to LF, but I'm steadily acquiring some gear in the hope of shooting a picture or two in the near future.

So, I now have a Rodenstock Sironar 150mm F5.6 from around 1973 with fairly major separation, and I'm looking to fix it. It didn't cost me much and it wouldn't be worth a lot fixed, so first thought was to have a go myself using the info on the web. The plan was to separate the elements using methylene chloride and re-cement using Norland 61 UV curing glue.

However, having removed the offending glass, I've discovered it's actually 3 cemented elements and they aren't identical diameters or aligned on their sides - so I'm now doubting my ability to re-cement them in the correct alignment. I've asked Focal Point for a quote, but I'm anticipating that it will not be economical, and I'm after any advice.

http://www.yatecourtbarn.adsl24.co.uk/images/IMGP0683.JPG

http://www.yatecourtbarn.adsl24.co.uk/images/IMGP0684.JPG

http://www.yatecourtbarn.adsl24.co.uk/images/IMGP0686.JPG

Patrick Dixon
17-Apr-2009, 12:11
The quote is $225 inc post, so not really economical.

Gene McCluney
17-Apr-2009, 12:24
You should be able to replace the lens with a good one for about the same price.

Dan Fromm
17-Apr-2009, 14:19
Um, Patrick, Sironars were six elements in two groups. The front cell has a cemented doublet and a singlet. The front group (doublet) rests on the first step, the second group (singlet) rests on the third step, and there's air between them.

I've never had the opportunity to look at a Sironar closely, but your pictures make me think that the groups are swaged into their holders. If so, getting the front out and replacing it will be problematic. Its hard to tell, but I think the rear group in its little holder will screw out; all of my 6/4 plasmats' inner groups unscrew ...

About prices, consider again. Lenses in that class (mid-'70s 6/4 150/5.6 Plasmat) in shutter still sell for more than $225 when in good order. If you can find a Symmar or Sironar in a dead shutter (#1?) for a good price, that would be a good replacement. Otherwise Focal Point is probably your best option.

In my experience, prices quoted here ("You should be able to get a good one for ...") are optimistic. And this even though I once bought a 135/5.6 Symmar in barrel for $32 delivered and had a #0 shutter waiting for it. Another time I bought 10 38/4.5 Biogons for $580 delivered but this doesn't mean that you can buy one for $58.

Good luck, have fun,

Dan

GPS
17-Apr-2009, 14:41
Next time you think you can do Rodenstock's job in your kitchen you will know the answer. Buy a new lens and thank life for its lessons - that's how we learn, don't we?

Patrick Dixon
17-Apr-2009, 14:43
Many thanks for your help GPS. You obviously have plenty of money so you must be a banker?

(And obviously, had Rodenstock done the job properly in the first place, there wouldn't be numerous tales of Rodenstock lens separation all over the internet.)

GPS
17-Apr-2009, 14:47
Many thanks for your help GPS. You obviously have plenty of money so you must be a banker?

Help? Didn't you get enough of it from your experience? When it comes to the money I have more of the common sense than money. It helps, believe me...:)

GPS
17-Apr-2009, 14:54
Many thanks for your help GPS. You obviously have plenty of money so you must be a banker?

(And obviously, had Rodenstock done the job properly in the first place, there wouldn't be numerous tales of Rodenstock lens separation all over the internet.)

OK, you want more help. Ask Rodenstock to sell you their centering device for lenses so that you can cement them correctly in your kitchen "using the info on the web".
You will get a lesson # 2. (You asked for it, didn't you..?)

GPS
17-Apr-2009, 14:57
Many thanks for your help GPS. You obviously have plenty of money so you must be a banker?

(And obviously, had Rodenstock done the job properly in the first place, there wouldn't be numerous tales of Rodenstock lens separation all over the internet.)

Why don't you then open a repair service for those lenses? Beat Rodenstock to pieces...:)

erie patsellis
17-Apr-2009, 21:10
well, if you just want to use the lens, use a light oil and very carefully allow it to wick in from one edge, it will take a couple of days and you'll probably have to reapply a few times. (if you PM me, I can send you a quick rundown sent to me by a repair person that's been using this technique for years)

Will it be perfect? No, but it will be far better than what it is right now. (and fully usable, though resale value will be little to none) Of course, those with deeper pockets than mine would replace it with whatever trendy, expen$ive lens is the current rage, but if you just want to make pictures, try it, you may be surprised.

CatSplat
17-Apr-2009, 21:53
Next time you think you can do Rodenstock's job in your kitchen you will know the answer. Buy a new lens and thank life for its lessons - that's how we learn, don't we?

Man, with comments like that you're sure to get coal in your stocking come Christmas.


...or a Gran View.

GPS
17-Apr-2009, 23:39
well, if you just want to use the lens, use a light oil and very carefully allow it to wick in from one edge, it will take a couple of days and you'll probably have to reapply a few times. (if you PM me, I can send you a quick rundown sent to me by a repair person that's been using this technique for years)

Will it be perfect? No, but it will be far better than what it is right now. (and fully usable, though resale value will be little to none) Of course, those with deeper pockets than mine would replace it with whatever trendy, expen$ive lens is the current rage, but if you just want to make pictures, try it, you may be surprised.

Erie, to use this repair is asking for future troubles. Unless you seal the oil hermetically (and even so!), whether you like it or not, the oil will dessicate and leave a residue or invite all kinds of fungi to grow on. A lens with a severe separation is repairable only with a professional repair - i.e. re-cementing.

GPS
17-Apr-2009, 23:51
Man, with comments like that you're sure to get coal in your stocking come Christmas.


...or a Gran View.

Now, what is your advice, wise man?

Patrick Dixon
17-Apr-2009, 23:58
Well I'm new here and new to LF, but GPS's advice seems like something I could live without.

Thanks for the other contributions.

GPS
18-Apr-2009, 00:37
Do you have a better idea than the one I gave you? By all means let us know...

GPS
18-Apr-2009, 00:57
...
(And obviously, had Rodenstock done the job properly in the first place, there wouldn't be numerous tales of Rodenstock lens separation all over the internet.)

If Bob Salomon is around here he will maybe give you a more realistic view of the quality of Rodenstock lenses...:)

Patrick Dixon
18-Apr-2009, 01:58
I have no doubt about the optical quality, but it seems clear that with this particular generation of lens, Rodenstock had a manufacturing problem in that they used a cement or a cementing process that frequently failed prematurely.

From what I've read, they replaced/repaired some lenses under warranty even up to 10 years from the original purchase date, but there still seems to be a fair number of examples with separation problems out there, and as a consequence Rodenstock lens separation is as legendary as Schneideritis.

This lens owes me nothing, and I can buy an example of the same lens here in the UK for 150 with a dealer warranty (although, given the separation issue, I'd probably prefer to buy a Schneider one for a little more). Therefore a 'professional' repair at $225 is not economical, and I have nothing to loose by attempting a repair of my own. I don't have a kitchen table to work on, but I can use my workbench if that's OK with you?

I've had another good look at the group, and AFAIK see or feel there is no metal housing and what you see on the sides in the photo is just matt black paint. I don't think the rear element unscrews from the front two, unless the glass itself is threaded.

The earlier Sironars may not be quite the same construction as the current -S, -N or -W version. I can't find any technical info on them at all, and the filter size is different to current production, so I still think it's likely to be three cemented elements.

Before attempting to separate them, I think I'll make up an jig from aluminum or steel which I can use it to re-cement them in the same alignment. But I might try the oil first, as it can't do any harm and would get cleaned out when separating them anyway.

GPS
18-Apr-2009, 02:33
I have no doubt about the optical quality, but it seems clear that with this particular generation of lens, Rodenstock had a manufacturing problem in that they used a cement or a cementing process that frequently failed prematurely.

From what I've read, they replaced/repaired some lenses under warranty even up to 10 years from the original purchase date, but there still seems to be a fair number of examples with separation problems out there, and as a consequence Rodenstock lens separation is as legendary as Schneideritis.

This lens owes me nothing, and I can buy an example of the same lens here in the UK for 150 with a dealer warranty (although, given the separation issue, I'd probably prefer to buy a Schneider one for a little more). Therefore a 'professional' repair at $225 is not economical, and I have nothing to loose by attempting a repair of my own. I don't have a kitchen table to work on, but I can use my workbench if that's OK with you?

...

For the first part of your post I hope Bob, who knows about Rodenstock lenses something, will chime in.

For the second part I would suggest that your kitchen table might be a better place for your experiment as there is with all the probability less dust around than on your workbench...
If you decide to buy from Rodenstock the alignment bench and tools don't forget to buy it together with the clean room they work in, and the dust removing accessory otherwise you risk to cement the dust, lint and fibers present around your workshop to the lens forever... Best bet would be to purchase it with a Rodenstock technician too...
Good luck in your endeavor!

Patrick Dixon
18-Apr-2009, 02:53
When it comes to the money I have more of the common sense than money.If only you'd shown it in this thread.

Maybe this is not the forum for me ...

GPS
18-Apr-2009, 03:11
If only you'd shown it in this thread.

Maybe this is not the forum for me ...

If you think I haven't shown the common sens in this thread tell me where, if I did, why do you complain?
Don't despair yet - the forum is for everyone, just don't expect that all answers must please you. My common sens tells me that what is rather not for you is re-cementing a modern Rodenstock lens on your workbench...:)

Patrick Dixon
18-Apr-2009, 04:18
Instead your 'common sense' tells me that I should spend more than the lens would cost to replace on a 'professional' repair :-(

You have completely thread-crapped this thread!

GPS
18-Apr-2009, 04:35
Instead your 'common sense' tells me that I should spend more than the lens would cost to replace on a 'professional' repair :-(

You have completely thread-crapped this thread!

If you want to have a healthy Rodenstock 150mm lens to use instead of your unusable specimen what is your suggestion that is not "crapping the thread"?

Bob Salomon
18-Apr-2009, 04:39
For the first part of your post I hope Bob, who knows about Rodenstock lenses something, will chime in.

For the second part I would suggest that your kitchen table might be a better place for your experiment as there is with all the probability less dust around than on your workbench...
If you decide to buy from Rodenstock the alignment bench and tools don't forget to buy it together with the clean room they work in, and the dust removing accessory otherwise you risk to cement the dust, lint and fibers present around your workshop to the lens forever... Best bet would be to purchase it with a Rodenstock technician too...
Good luck in your endeavor!

The first part is pure nonsense. We have only been the US Rodestock distributor since the 80s and separation on lenses made while we have been the distributor have been virtually non-existent. Same with lenses sold by the former distributor, Berkey. If their was a problem earlier then that then the owners are not contacting us about it.

If there have been 20 calls regarding separation in the more then 23 years that we have distributed Rodenstock and the 30+ years that we have been the Linhof distributor it would have been a lot.

Patrick Dixon
18-Apr-2009, 05:05
The first part is pure nonsense.

I'm not sure what you're referring too. If you care to google for "Rodenstock lens separation", you'll find a few references.

Are you saying I should send this back to Rodenstock and they'll sort it? I'd be impressed if that was the case.

Patrick Dixon
18-Apr-2009, 05:09
If you want to have a healthy Rodenstock 150mm lens to use instead of your unusable specimen what is your suggestion that is not "crapping the thread"?

Look, your advice is to spend more than the lens is worth to get it repaired. You could have said that in one post and moved on, but you seem determined just to thread-crap. You haven't managed one constructive or 'common sense' suggestion - unlike the other respondents.

The question was, not how to have a healthy Rodenstock 150mm lens - that's easy, the question was how to make this one usable/healthy economically.

GPS
18-Apr-2009, 05:50
The first part is pure nonsense. We have only been the US Rodestock distributor since the 80s and separation on lenses made while we have been the distributor have been virtually non-existent. Same with lenses sold by the former distributor, Berkey. If their was a problem earlier then that then the owners are not contacting us about it.

If there have been 20 calls regarding separation in the more then 23 years that we have distributed Rodenstock and the 30+ years that we have been the Linhof distributor it would have been a lot.

Thanks Bob, I knew the answer because you mentioned that earlier in some thread. Hopefully the OP will take your answer better than mine...

Steve M Hostetter
18-Apr-2009, 05:51
Ok guys,, be cool.. :) I had a 115mm 6.8 Grandagon and it had slight separation.. The saleman told me up front and I sent the lens to Grimes for a fix at $250.00 about 10 years ago..
I love Grandagon lenses and it was worth it "to me" to do that with that particular lens..even though it was an older uncoated lens..

Capocheny
18-Apr-2009, 05:56
Hi Patrick,

If the shutter on your lens is working properly then it might be a better bet just to send the lens in to Focal Point and have them do it... UNLESS you can find the same lens in a newer black shutter for the same price as the repair.

To me, THAT would make good common sense!

Although I get what GPS was saying in his first post... it might have needed a smiley as I don't think he was deliberately trying to get under your skin. :)

This IS a terrific forum and there are some GREAT people here who try and help sort things out for newbies and experienced shooters alike. So, don't depart on account of one (or the occasional) thread that rubbed you the wrong way.

Anyway, when I first got into LF photography, I bought a kit that included an older vintage Roddie 90mm f4.5. Although the separation on my lens wasn't as extensive as yours... it, too, had a separation on one area that grew larger with time. I contacted the manufacturer about having it repaired and they replied back that it would have to be sent back to Germany for the job. Secondly, they said it would be less expensive to just purchase a new lens.

Unfortunately, I hadn't heard of Focal Point at that time. Consequently, the front and rear lens elements wre simply disposed of. Had I have known about an alternative service provider at that time... I'd probably have sent it in to them for the repair. :)

In my case, it was a lesson learned the hard way. That's why I think Dan's suggestion is the most logical way of going. The guys at Focal Point have probably performed this repair a few times and have the necessary experience/equipment to do a decent job of it.

[BTW, I never did buy another 90 but did eventually buy a 110XL MANY. MANY years later. :)]

Good luck on whatever decision you make.

Cheers

GPS
18-Apr-2009, 05:59
Look, your advice is to spend more than the lens is worth to get it repaired. You could have said that in one post and moved on, but you seem determined just to thread-crap. You haven't managed one constructive or 'common sense' suggestion - unlike the other respondents.

The question was, not how to have a healthy Rodenstock 150mm lens - that's easy, the question was how to make this one usable/healthy economically.

You refused the idea of re cementing the lens professionally. You refused the idea of buying another Rodenstock lens. If these ideas are not constructive for you what is? Re-cementing the lens at home on your workbench? Good luck!
You asked for ANY advice. If you don't like the advice you got - get over it. Is that advice constructive enough? Good luck!

Kevin Crisp
18-Apr-2009, 06:05
PM sent.

GPS
18-Apr-2009, 06:06
Indeed Capocheny,
to take apart a lens and to see that "I cannot do it" is a good and valuable lesson in the life - much better than to start some home recementing only to get even a bigger piece of ... after. I don't get it what is so irritating for some to learn from life's lessons this way. Anyway, I think Patrick got all the reasonable advice he could get as there is surely not anyone who recemented modern Rodenstock lenses at home...
"A big smiley here"

Bob Salomon
18-Apr-2009, 06:26
I'm not sure what you're referring too. If you care to google for "Rodenstock lens separation", you'll find a few references.

Are you saying I should send this back to Rodenstock and they'll sort it? I'd be impressed if that was the case.

Patrick,

Your lens is decades out of warranty. We and the factory would recommend replacing, not repairing. There are various causes of this problem but the most common one is handling of the lens where it receives small impacts which creates a hole, pinhole or larger, in the sealant around the cells which eventually let moisture in. With the adhesives mandated by German law for optics 30+ years ago, combined with the moisture infiltration, there seems to be some separation effect that was more common in all German made lenses of that era then newer lenses. But in any case it is not a warranty issue.

Kevin Crisp
18-Apr-2009, 06:34
"there is surely not anyone who [successfully] recemented modern Rodenstock lenses at home..." GPS -- you might be wrong about that too.

Steve M Hostetter
18-Apr-2009, 06:38
I have a Schneider 480mm 8.4 APO that has issues.. you can hear the glass elements clang when you turn the lens up-side down..

Patrick Dixon
18-Apr-2009, 06:49
Patrick,

Your lens is decades out of warranty. We and the factory would recommend replacing, not repairing. There are various causes of this problem but the most common one is handling of the lens where it receives small impacts which creates a hole, pinhole or larger, in the sealant around the cells which eventually let moisture in. With the adhesives mandated by German law for optics 30+ years ago, combined with the moisture infiltration, there seems to be some separation effect that was more common in all German made lenses of that era then newer lenses. But in any case it is not a warranty issue.
Fair enough - that's what I'd expect.

Patrick Dixon
18-Apr-2009, 06:52
... much better than to start some home recementing only to get even a bigger piece of ... after.

I'm really struggling to understand how you think you can make a useless, uneconomically repairable lens, that the manufacturer recommends you place gently in the bin, any worse!

GPS
18-Apr-2009, 07:01
I'm really struggling to understand how you think you can make a useless, uneconomically repairable lens, that the manufacturer recommends you place gently in the bin, any worse!

OK, I'll help you to understand. You can make the lens worse by taking it apart, dissolving the edge blackening and the old cementing and not being able to realign and to re-cement it back again. :) :) :)

GPS
18-Apr-2009, 07:05
"there is surely not anyone who [successfully] recemented modern Rodenstock lenses at home..." GPS -- you might be wrong about that too.

I might - unless you prove me wrong, you're not right either...:) :) :)

Patrick Dixon
18-Apr-2009, 07:51
OK, I'll help you to understand. You can make the lens worse by taking it apart, dissolving the edge blackening and the old cementing and not being able to realign and to re-cement it back again. :) :) :)

How does that make it worse if it is worthless in the first place? :-( :-(

Less than worthless .... ?

Patrick Dixon
18-Apr-2009, 07:52
I drew the short straw here ....

Bob Salomon
18-Apr-2009, 09:06
I drew the short straw here ....

No you don't. You are just the newest one here.

From your previous post you seem to be buying product based on cost as opposed to features and condition. If you had bought a camera with full movements to start with you would not automatically go into the modify it mode.

If you had checked before buying a lens with separation about how feasible it is to fix it (we tell owners that it isn't worth it with lenses that old) you would have good quality cameras and lenses in working condition that would do what you want without having to spend much, if any more, and that would do what you want to do now and grow into what you want to do in the future.

You just have people who have been here longer, have been doing it longer who are trying to help you. But if the answers from those people are not what you want to hear that does not mean that you should go away. Not everything is a DIYS project. And it does not mean that anyone is belittling you.

Kevin Crisp
18-Apr-2009, 09:16
Unless, GPS, there is something uniquely different about the construction of Rodenstock lenses (and I have not seen that in ones I have had apart) then this can be done successfully as a home repair. I say that having reglued more than 40 lenses at home, not counting the "redo's" on the beginning of the learning curve. The majority of those were protars, which involve 4 pieces of glass and 3 cemented surfaces. Protars are a more difficult job for cleaning, centering, pre-cure and cure.

Now if, based on your experience in repairing lenses at home, this particular project is impossible for a DIY person to handle for some reason thus far undisclosed, then please elaborate on why. Maybe there is something about it that would make it a particularly difficult repair. If this is the case, what is it?

If you are just answering in the abstract, drawing from your fund of general knowledge to deliver a dose of discouragement, then I don't see the point of it. Why not just stop arguing with the new participant? No one trying to learn to do this from what is out there on the Web could possibly conclude it was easy. When Mr. Grimes informed us in his article that he uses a drop of cement, the size of which is 'based on experience,' you know this is going to take some getting used to.

Kevin Crisp
18-Apr-2009, 09:49
And, just to be clear about it, it can't be argued that even a DIY repair is "cost effective," unless you enjoy fixing things and then using them.

GPS
18-Apr-2009, 10:23
Unless, GPS, there is something uniquely different about the construction of Rodenstock lenses (and I have not seen that in ones I have had apart) then this can be done successfully as a home repair. I say that having reglued more than 40 lenses at home, not counting the "redo's" on the beginning of the learning curve. The majority of those were protars, which involve 4 pieces of glass and 3 cemented surfaces. Protars are a more difficult job for cleaning, centering, pre-cure and cure.

Now if, based on your experience in repairing lenses at home, this particular project is impossible for a DIY person to handle for some reason thus far undisclosed, then please elaborate on why. Maybe there is something about it that would make it a particularly difficult repair. If this is the case, what is it?

If you are just answering in the abstract, drawing from your fund of general knowledge to deliver a dose of discouragement, then I don't see the point of it. Why not just stop arguing with the new participant? No one trying to learn to do this from what is out there on the Web could possibly conclude it was easy. When Mr. Grimes informed us in his article that he uses a drop of cement, the size of which is 'based on experience,' you know this is going to take some getting used to.

Now Kevin, if you have this unique experience of re-cementing Rodenstock lenses why don't you just give Patrick the advice he's wanting so badly? I'm sure many others would be curious about it, me too. Or do you have reasons not to share it with us?
When it comes to my reasons for not trying to do this as a DIY project I've already touched some of them in my posts.
Your lessons about arguing you can keep them for yourself, they can be handy for you...:)
And indeed, I'm discouraging Patrick from re-cementing this lens and I'm not the only one, you have surely noticed. Different people, different opinions...

Patrick Dixon
18-Apr-2009, 11:05
No, there's you and Bob - who want's me to buy a new lens (for some reason)!

For Bob's benefit:

I bought a cheap LF camera because I wanted to see how I got on with the format. I'm not one of those people who goes out and spends thousands on their new hobby, just to find I only do it twice, and TBH, I'd be embarrassed to go out with a fancy new camera and lenses and take the sh1T pictures that I probably will. I haven't modified anything yet and I haven't taken a picture, but I've already learned that there isn't a camera that will do everything the way everyone wants it.

I got this lens free. I don't like to see things go to waste even if it does help us propagate our consumerist society, and if I can have some fun 'restoring' it to it's former glory and gain a sense of achievement in the process, what's wrong with that?

I don't have any problem with your answers, it's what I'd expect you to say in your position, but I do have a problem with someone who takes half the posts in a thread to tell you 'he wouldn't do it like that' - when one would be quite sufficient.

Bob Salomon
18-Apr-2009, 11:12
No, there's you and Bob - who want's me to buy a new lens (for some reason)!

Patrick, I don't expect anyone who buys for as low as possible to buy a new lens or even a recent lens. But you should buy at least a serviceable lens. Not something that has problems that are not easily overcome. Even when it was free.

And yes, we would have loved for you to have bought a new Linhof Master Technika, TechniKardan or a Wista. But we know that the vast majority of newcomers to large format do not buy new and they do not buy top of the line.

But a used Calumet CC is not very expensive today and a Pressman is totally obsolete. Had you checked before buying it you would have found numerous inexpensive modern type view cameras at dealers all over the country who would have been more then happy to have directed you into a camera that would grow with you.

GPS
18-Apr-2009, 11:20
No, there's you and Bob - who want's me to buy a new lens (for some reason)!

...
I don't have any problem with your answers, it's what I'd expect you to say in your position, but I do have a problem with someone who takes half the posts in a thread to tell you 'he wouldn't do it like that' - when one would be quite sufficient.

For goodness sake, do whatever pleases you more, if that takes the "problem" away from you...:)

Gene McCluney
18-Apr-2009, 11:28
You got the lens for free you say? Well, then even if you don't fix the glass, you got a good shutter you could use for another lens (that will fit), or you could sell the shutter here and use that to partially fund a working lens. You did OK.

Patrick Dixon
18-Apr-2009, 11:39
Bob, I've actually got a couple of serviceable lenses (although probably not ones that you'd approve of!). I should say I'm in the UK, so the market is slightly different, but nevertheless I take your point.

For the kind of photography I'd like to do, I should probably buy an Ebony because that's what the 'pros' use. I considered buying a Chamonix or a Metal Field Toyo, but both were more expensive than the Pressman and I don't yet know enough about how I'd use them to know which I'd prefer. The Pressman, whilst old and flawed, will still allow me to make all my beginners mistakes (like mixing up the film holders and forgetting to close the lens) just as effectively as a more accomplished camera, and when I buy my next camera, I'll have a better idea of what I need.

Patrick Dixon
18-Apr-2009, 11:42
You got the lens for free you say? Well, then even if you don't fix the glass, you got a good shutter you could use for another lens (that will fit), or you could sell the shutter here and use that to partially fund a working lens. You did OK.

Thanks - yes I think so! And nothing I do to the glass will have a negative affect on the shutter (which seems to work well).

Bob Salomon
18-Apr-2009, 12:16
because that's what the 'pros' use.

Nonsense,

Pros use what works for them be it Linhof, Sinar, Arca, Canham, Phillips, Toyo, Arca, Graflex, etc.

You live in the UK then there are quite a few dealers that sell large format. Many may also have connections to seminars on using large format. Get out and visit some of the dealers and see what "pros" use. Not just the few that are on line.

Kevin Crisp
18-Apr-2009, 13:18
GPS -- I did in fact send Patrick a private message offering to walk him through the process. That was the first thing I did. If he answers it I will be happy to do so. I also offered to recement it for him. That seems going above and beyond trying to be helpful.

What you did was tell him that $225 plus post was not economical, something any adult can evaluate without help from the forum. Then the potshots started because you had difficulty with someone not accepting your input as being weighty or pertinent.

Since you have not answered my question specifically beyond general reference to your earlier posts -- none of which contain the answer, naturally -- I assume you don't have personal knowledge on this subject and you are aware of nothing distinctly different about Rodenstock 150mm lenses that makes them unrepairable for the DIYer.

GPS
18-Apr-2009, 13:31
"26-Mar-2008, 16:17 #21
Kevin Crisp


Posts: 1,121 Re: Sick Grandagon Seeks Specialist (4x300kb imgs)

--------------------------------------------------------------------------------

Grimes personally did this work and his company no longer does it. Focal Point is excellent, they really know what they are doing. I have also used these people: http://www.optil.co.uk/ and their work was super too. And at least on the one project they did for me (separate and cement and coat a 19" protar element) the price was reasonable. Either way this is a $250 to $350 proposition, I suspect.

An oven is a really bad idea on modern cement. If the separation has gone far enough you may be able to disassemble the lens element with the problem and just gently pull it apart, otherwise there is a special high temp solvent used to take apart modern cement. A long soak in acetone may do it if the separation is already well advanced as appears to be the case with yours. I have had to undo some modern repairs and weeks of soaking in acetone will break down the cement. Check the Summers Optical website for details on the high temp solvent if you need to go that route. If you can just pull it apart and clean it up with acetone then recementing is not that hard but alignment is the hard part once you learn to get the surfaces really clean and learn to judge the size of the drop of cement you need. A UV bulb can be used for pre-cure and curing. Where lenses elements are of different diameters the alignment gets really tricky and with a wide angle, it is really important.

You might consider a new lens for all of the above reasons. Or give the repair a try since selling it will get you the price of used shutter. Good luck. "
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Here is your post Kevin, from the last year. Little did I know...
Interesting to see how you speak about the same difficulties that I touched in my reasoning... I hope you were so sincere in your info to Patrick about his idea of re-cementing as you were about it in your old thread...
Glad to see we agree at least on something... Rodenstocks with different lens elements diameters could be difficult to center correctly, couldn't they...
I had that feeling knowing the use of laser collimating processes in Rodenstock factories...
So much for your educational lessons...

GPS
18-Apr-2009, 13:35
GPS -- I did in fact send Patrick a private message offering to walk him through the process. That was the first thing I did. If he answers it I will be happy to do so. I also offered to recement it for him. That seems going above and beyond trying to be helpful.

What you did was tell him that $225 plus post was not economical, something any adult can evaluate without help from the forum. Then the potshots started because you had difficulty with someone not accepting your input as being weighty or pertinent.

Since you have not answered my question specifically beyond general reference to your earlier posts -- none of which contain the answer, naturally -- I assume you don't have personal knowledge on this subject and you are aware of nothing distinctly different about Rodenstock 150mm lenses that makes them unrepairable for the DIYer.

If you didn't find the answers it's not my fault. My personal knowledge I showed more than clearly to those who want to see it. It's not my fault you didn't get it.
Good luck with your collimating work!:)

GPS
18-Apr-2009, 13:39
GPS -- ...
What you did was tell him that $225 plus post was not economical, something any adult can evaluate without help from the forum. ...

Any dude can see that I never said anything like this to Patrick... Can't you?:)

Nathan Potter
18-Apr-2009, 14:16
Patrick, despite all the back and forth here people do separate lenses and re-cement at home. It is a bit of a pain in the ass. And you won't be able to align the elements with the accuracy possible in an optical lab or control the gap between elements as exactly. But hey - you may not notice the degradation in optical performance either. If not already done, google lens cementing and you'll find lots of info.

You really only want a salvage operation at no cost so I would encourage you to try it - I've done it a couple of times but am no expert. Some comments:

Methylene chloride is a suspected carcinogen so try not to breath the fumes or get it on your skin. But it is a good separation solvent.

You don't know what the cement composition was in your lens but just try canada balsam for repair. You'll need about 300 to 350 degrees F for heat.

As GPS says try to work in a dust free area in order to keep the interface between elements clean.

Suspend the lens (to avoid scratching) above the hot surface using an outer ring support.

You can't reasonably control the thickness of the gap between elements during bonding and that, as well as the index of the bonding medium affects the optical performance after sealing. Maybe use about 5 ml of balsam placed in the middle of the negative element. Try to squeeze out the bubbles and center the elements.

Cool the lens pair slowly after sealing.

Hey, it's not all that difficult to do a credible job; but optically perfect it won't be.

Nate Potter, Austin TX.

Kevin Crisp
18-Apr-2009, 14:24
Patrick -- As I offered you in my email, if you want to try doing this yourself I am happy to help you avoid some of the missteps you might make if you take your directions off the Internet. It can be done with some practice. There are work arounds on the alignment issue.

On the bright side, if you got a working shutter for free, you got a good deal.

There are a lot of people on this forum who generously share their knowledge about many things and they are almost always helpful and the threads very, very rarely degenerate like this one. So please don't view this posting experience as typical because it certainly isn't.

Finally, if you go back in the list of posts above to No. 53, where GPS has included one of my prior postings, that post did include a link to a UK company that repairs lenses. (I think the outfit is Ballham Ltd. in London but I may have the spelling wrong.) I think that could bring the cost down for you. I had them reglue and coat a 19" Protar element for me and the work was excellent. The price was pretty reasonable but part of that could have been that I had separated and cleaned the elements myself. You only need one surface redone so the job is relatively simple.

Anyway, good luck with your lens. If I am interpreting your photos correctly the middle of the lens is not separated. You might consider stopping down to f:22 of f:32 and trying it out. You may be pleasantly surprised.

Chauncey Walden
18-Apr-2009, 15:16
I agree with Kevin. The separated lens probably has had more harm done to its resale value than its picture taking ability, and I speak from experience on this. It may well make better images as is than it will after your attempt to correct it.

Dan Fromm
18-Apr-2009, 15:36
Um, Patrick, I've told you once that your Sironar has six elements in four groups. I doesn't have six elements in two groups. The practical significance of this news, that neither cell holds three elements cemented together, seems to have escaped you.

Take the cell that you've extracted from its shutter and count reflections. You'll find four strong reflections, from air-glass interfaces, and one weak one, from the outer group's glass-cement-glass interface. If all three elements were cemented together you'd see two strong and two weak reflections. Please report what you find.

Kevin and Chauncey's advice to try the lens out is good. FWIW, I have a badly separated 58/5.6 Grandagon that's usable.

Chauncey Walden
18-Apr-2009, 17:56
Just a note - the Lens Vade Mecum includes this comment in its description of the pre-N Sironars: "(Sadly a number sold in the UK including the last example, seem to have suffered from a faulty supply of balsam, and have separated. One report has been that this actually did not affect the performance seriously as with the example seen and the lens was regularly used in spite of it: but it must reduce the value of the lens considerably. A repairer says that rebalsaming here is not normally possible...)"

Patrick Dixon
19-Apr-2009, 02:08
Um, Patrick, I've told you once that your Sironar has six elements in four groups. I doesn't have six elements in two groups. The practical significance of this news, that neither cell holds three elements cemented together, seems to have escaped you.

Not at all, you obviously missed my reply to that in all the crap!

I've had a good look at the element, and I'm pretty sure it's 3 cemented lenses. The early Sironars seem to be different to the latter -S -N -W ones, so maybe the construction is different too. If you can point me at any data I'd be interested since I haven't found any myself. The front filter size is completely different too.

Patrick Dixon
19-Apr-2009, 02:10
GPS -- I did in fact send Patrick a private message offering to walk him through the process.

Thanks Kevin, you should have already had a PM back.

Patrick Dixon
19-Apr-2009, 02:17
Nonsense,

Pros use what works for them be it Linhof, Sinar, Arca, Canham, Phillips, Toyo, Arca, Graflex, etc.


Most of the top UK landscape LF people favour Ebony. There's one that uses a TK.

Anyway, you're missing my point.

Kevin Crisp
19-Apr-2009, 05:36
The appearance of the fault as a rainbow, with that shape, with no crystallization, all are inconsistent with this being a balsam cemented lens. If it dates from the early 1970's I also think use of balsam is extremely unlikely based on that alone.

I share the puzzlement over the mechanical construction. Normally in a somewhat modern plasmat the large front group is cemented together (that certainly looks like what is coming apart here) then there is an air space, then the smaller coated rear element. This looks like one cemented group, although there may be a painted over metal piece holding the rear group. Hard to say without seeing it in person. There is a way to separate just the first bond, which is where the problem is.

Patrick, I did not get an email either to the address I gave you or through the forum.

Bob Salomon
19-Apr-2009, 05:39
Most of the top UK landscape LF people favour Ebony. There's one that uses a TK.

Anyway, you're missing my point.

Check with the dealers that actually sell the cameras. Pros use what works for them.

Patrick Dixon
19-Apr-2009, 07:35
Patrick, I did not get an email either to the address I gave you or through the forum.

I've emailed you. I don't know what happened to my PM!

Kevin Crisp
19-Apr-2009, 09:01
Hmmm. Weird. I still have nothing through the forum or the work email address. I've sent you another PM with another email address.

Dan Fromm
19-Apr-2009, 09:25
Patrick, thanks for the reply. There certainly was a lot of crap flying and seeing through it wasn't easy.

Now, about y'r lens. The VM, which isn't always right, says that the jes' plain Sironar with no suffix is a 6/4 Plasmat. If your lens has only two strong reflections from each cell, it isn't a Sironar.

FWIW, early f/6.8 jes' plain Symmars are in fact 6/2 dagor types, later f/5.6 Symmars are 6/4 plasmat types like Sironars, Zircons, and some (not all) LF Nikkors and Fujinons.

Cheers,

Dan

halberstadt
12-Oct-2010, 18:59
I agree with Kevin. The separated lens probably has had more harm done to its resale value than its picture taking ability, and I speak from experience on this. It may well make better images as is than it will after your attempt to correct it.

I'm the owner of a 180mm Sironar vintage 1960's with separation issues (rainbows along the edges.) It's come to be one of my favorite lenses- sharp and contrasty. I bought the cells for almost nothing and happened to have a shutter lying around. If you don't care about resale value, just test the lens. And if anybody has some old Rodenstock lenses around they want to sell for peanuts that have separation problems, let me know! But since a nice standard lens for 4x5 can be had used for $50-200 there seems to be no point in fixing such a lens from my perspective.