Is it worth fixing/cleaning on this Tamron 55BB 500mm f/8.0 mirror

MattGunn · 03-03-2010, 01:02 PM

Based on the stuff you have fixed before you will have no trouble cleaning the Tamron 55BB. As I posted previously you can get at the mirror from the front by removing one retaining ring but the mirror can also be removed from the back by unscrewing the 6 screws on the rear face (I can't remember if you need to remove the trim ring around the outside first though) and a retaining ring. This is a lot more work, especially as the screws on mine were locktighted, but the access is better. It is a great lens, good luck with it.

hinman · 03-03-2010, 06:09 PM

Originally posted by Just1MoreDave

Now the pressure is on me! I am reasonably confident in my repair abilities, but can I match the above "before" photos? Probably not!

@Dave, I have confidence in you. What I shot in the series are just snap-shooting. And if you know me, I am the average Joe shooting dSLR like a p&s.

I never thought a mirror lens can be sharp and offer moderate contrast that can be tuned in post processing. Was I so wrong on my subjective and negative views before. I was biased towards mirror lens due to my previous not-so-great experience with cheap brand of mirror lens. The 55BB stands out.

When I re-edit some of the test shots with K-x, I am quite surprised with the sharpness. I can see the detail on the hummingbird feather and squirrel face without cropping. DOF in close distance is narrow and prone to user focus errors but I do find the focusing ring in 55BB to be outstanding for getting precision in manual focusing.

I was shooting quite far in at least 150 feet away from an bird's island in a park close to my home

cropped a bit to get closer

This mirror lens is promising.
Hin

Jean Poitiers · 09-28-2013, 03:56 AM

Thanks for this thread ... I have found a 55BB that needs cleaning ... J

manntax · 02-20-2015, 07:48 AM

Originally posted by Jean Poitiers

Thanks for this thread ... I have found a 55BB that needs cleaning ... J

Hello Jean , did you ever give it a go and cleaned that tamron?? How difficult it is to remove the front element and clean spot of fungus behind it? It looks like My lens has only this issue - it doesn't really affect the photos (although I still need to go properly out with it ) but I would really like to have it in top condition.

**Just1MoreDave** · 02-20-2015, 01:51 PM

There is a threaded ring just inside the filter ring that unscrews via the filter threads. Those threads need to be in decent shape or the ring will be difficult to unscrew. I can't remember if was locked in place with lacquer or not. If it was, I was able to dissolve it with some solvent. It has small square slots for a lens spanner tool. I remember having some trouble here because the filter size is 82mm, so a tool needs to go pretty wide to engage the slots. And the center spot fell off; it's just glued on.

manntax · 02-20-2015, 01:54 PM

Originally posted by Just1MoreDave

There is a threaded ring just inside the filter ring that unscrews via the filter threads. Those threads need to be in decent shape or the ring will be difficult to unscrew. I can't remember if was locked in place with lacquer or not. If it was, I was able to dissolve it with some solvent. It has small square slots for a lens spanner tool. I remember having some trouble here because the filter size is 82mm, so a tool needs to go pretty wide to engage the slots. And the center spot fell off; it's just glued on.

Thanks for stepping in - really helpful. Firstly , atfer I remove the ring the large glass element fells off in one piece with all glass elements and other parts of this front assembly? I just wanted clean the behind front glass where the spot is, so little bit worried about that central piece - will it somehow decenter if it fells off ?

**grahame** · 02-20-2015, 01:58 PM

Originally posted by IS050

I would highly recommend send it to Eric for his professional opinion.

Eric works on Pentax gears only. I once contacted him about a tokina lens and he said he couldn't work on that.

55bb is one of best mirror lens out there. definitely worth rescuing it.

Jean Poitiers · 02-20-2015, 02:11 PM

Originally posted by manntax

Hello Jean , did you ever give it a go and cleaned that tamron?? How difficult it is to remove the front element and clean spot of fungus behind it? It looks like My lens has only this issue - it doesn't really affect the photos (although I still need to go properly out with it ) but I would really like to have it in top condition.

Bonjour manntax,

I have not attacked my 55BB due to lack of time and really having very little fungus worth the intervention IMHO. I also later acquired a 55B which I like better due to its collar (etc.) and use it the most. I do not know if my spanner will "fit" the job (go wide enough). If not then I need to look at my other available tools (the big caliper) ... let me look at this again over the weekend and I will get back to you. Salut, J

**Just1MoreDave** · 02-20-2015, 02:35 PM - **1 Like**

Originally posted by manntax

Thanks for stepping in - really helpful. Firstly , atfer I remove the ring the large glass element fells off in one piece with all glass elements and other parts of this front assembly? I just wanted clean the behind front glass where the spot is, so little bit worried about that central piece - will it somehow decenter if it fells off ?

The large front element and one smaller element stuck to it can be removed as one piece when that retaining ring is unscrewed. These pieces are fairly thick and heavy. The rest stays in place when I tip the lens on its side. When I put the elements back into place, they seat solidly in place; I can't shift them at all. So I think decentering is not likely from misplacing that element. What fell off on my lens is just a cosmetic plastic cap.

manntax · 02-20-2015, 02:40 PM

Originally posted by Just1MoreDave

The large front element and one smaller element stuck to it can be removed as one piece when that retaining ring is unscrewed. These pieces are fairly thick and heavy. The rest stays in place when I tip the lens on its side. When I put the elements back into place, they seat solidly in place; I can't shift them at all. So I think decentering is not likely from misplacing that element. What fell off on my lens is just a cosmetic plastic cap.

Thank you - you have been very helpful - I will give it a go and be done with that annoying patch of fungus :P

---------- Post added 02-20-15 at 09:41 PM ----------

Originally posted by Jean Poitiers

I have not attacked my 55BB due to lack of time and really having very little fungus worth the intervention IMHO. I also later acquired a 55B which I like better due to its collar (etc.) and use it the most. I do not know if my spanner will "fit" the job (go wide enough). If not then I need to look at my other available tools (the big caliper) ... let me look at this again over the weekend and I will get back to you. Salut, J

Thanks for letting me know - I might be brave enough to do it this weeked anyways - looks to be fairly easy as per advice I got from Just1MoreDave

dme · 10-09-2017, 03:55 AM

This is an old thread, but I still think this Youtube link is relevant today, "Tamron SP 500mm mirror lens, stripped to clean fungus from mirror.

...

You Tube

fwcetus · 10-09-2017, 07:04 AM - **1 Like**

Originally posted by grahame

55bb is one of best mirror lens out there. definitely worth rescuing it.

The 55BB is definitely a superb (and, even with some higher market prices lately, relatively inexpensive) 500mm mirror lens, as grahame and others have stated. [And the 55B is no slouch, either.]

As for attempting to perform a supposedly minor lens repair or CLA, I personally have ruined enough lenses to finally learn that I myself should never ever try to do either again.

03-03-2010, 06:09 PM	#17
hinman Veteran Member Join Date: Oct 2006 Location: Fremont, CA Photos: Albums Posts: 3,473 Original Poster	Originally posted by Just1MoreDave Now the pressure is on me! I am reasonably confident in my repair abilities, but can I match the above "before" photos? Probably not! @Dave, I have confidence in you. What I shot in the series are just snap-shooting. And if you know me, I am the average Joe shooting dSLR like a p&s. I never thought a mirror lens can be sharp and offer moderate contrast that can be tuned in post processing. Was I so wrong on my subjective and negative views before. I was biased towards mirror lens due to my previous not-so-great experience with cheap brand of mirror lens. The 55BB stands out. When I re-edit some of the test shots with K-x, I am quite surprised with the sharpness. I can see the detail on the hummingbird feather and squirrel face without cropping. DOF in close distance is narrow and prone to user focus errors but I do find the focusing ring in 55BB to be outstanding for getting precision in manual focusing. I was shooting quite far in at least 150 feet away from an bird's island in a park close to my home cropped a bit to get closer This mirror lens is promising. Hin Last edited by hinman; 03-03-2010 at 06:17 PM.

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03-03-2010, 01:02 PM	#16
MattGunn Veteran Member Join Date: Jun 2009 Location: Wales Photos: Gallery Posts: 347	Based on the stuff you have fixed before you will have no trouble cleaning the Tamron 55BB. As I posted previously you can get at the mirror from the front by removing one retaining ring but the mirror can also be removed from the back by unscrewing the 6 screws on the rear face (I can't remember if you need to remove the trim ring around the outside first though) and a retaining ring. This is a lot more work, especially as the screws on mine were locktighted, but the access is better. It is a great lens, good luck with it.

09-28-2013, 03:56 AM	#18
Jean Poitiers Pentaxian Join Date: Apr 2011 Location: Lost in translation ... Photos: Gallery \| Albums Posts: 18,076	Thanks for this thread ... I have found a 55BB that needs cleaning ... J

02-20-2015, 07:48 AM	#19
manntax Veteran Member Join Date: Jan 2012 Photos: Albums Posts: 1,972	Originally posted by Jean Poitiers Thanks for this thread ... I have found a 55BB that needs cleaning ... J Hello Jean , did you ever give it a go and cleaned that tamron?? How difficult it is to remove the front element and clean spot of fungus behind it? It looks like My lens has only this issue - it doesn't really affect the photos (although I still need to go properly out with it ) but I would really like to have it in top condition.

02-20-2015, 01:51 PM	#20
Just1MoreDave Site Supporter Join Date: Feb 2007 Location: Aurora, CO Photos: Gallery \| Albums Posts: 6,340	There is a threaded ring just inside the filter ring that unscrews via the filter threads. Those threads need to be in decent shape or the ring will be difficult to unscrew. I can't remember if was locked in place with lacquer or not. If it was, I was able to dissolve it with some solvent. It has small square slots for a lens spanner tool. I remember having some trouble here because the filter size is 82mm, so a tool needs to go pretty wide to engage the slots. And the center spot fell off; it's just glued on.

02-20-2015, 01:54 PM	#21
manntax Veteran Member Join Date: Jan 2012 Photos: Albums Posts: 1,972	Originally posted by Just1MoreDave There is a threaded ring just inside the filter ring that unscrews via the filter threads. Those threads need to be in decent shape or the ring will be difficult to unscrew. I can't remember if was locked in place with lacquer or not. If it was, I was able to dissolve it with some solvent. It has small square slots for a lens spanner tool. I remember having some trouble here because the filter size is 82mm, so a tool needs to go pretty wide to engage the slots. And the center spot fell off; it's just glued on. Thanks for stepping in - really helpful. Firstly , atfer I remove the ring the large glass element fells off in one piece with all glass elements and other parts of this front assembly? I just wanted clean the behind front glass where the spot is, so little bit worried about that central piece - will it somehow decenter if it fells off ?

02-20-2015, 01:58 PM	#22
grahame Loyal Site Supporter Join Date: Aug 2011 Photos: Albums Posts: 2,041	Originally posted by IS050 I would highly recommend send it to Eric for his professional opinion. Eric works on Pentax gears only. I once contacted him about a tokina lens and he said he couldn't work on that. 55bb is one of best mirror lens out there. definitely worth rescuing it.

02-20-2015, 02:11 PM	#23
Jean Poitiers Pentaxian Join Date: Apr 2011 Location: Lost in translation ... Photos: Gallery \| Albums Posts: 18,076	Originally posted by manntax Hello Jean , did you ever give it a go and cleaned that tamron?? How difficult it is to remove the front element and clean spot of fungus behind it? It looks like My lens has only this issue - it doesn't really affect the photos (although I still need to go properly out with it ) but I would really like to have it in top condition. *Bonjour* manntax, I have not attacked my 55BB due to lack of time and really having very little fungus worth the intervention IMHO. I also later acquired a 55B which I like better due to its collar (etc.) and use it the most. I do not know if my spanner will "fit" the job (go wide enough). If not then I need to look at my other available tools (the big caliper) ... let me look at this again over the weekend and I will get back to you. *Salut,* J

02-20-2015, 02:35 PM - 1 Like	#24
Just1MoreDave Site Supporter Join Date: Feb 2007 Location: Aurora, CO Photos: Gallery \| Albums Posts: 6,340	Originally posted by manntax Thanks for stepping in - really helpful. Firstly , atfer I remove the ring the large glass element fells off in one piece with all glass elements and other parts of this front assembly? I just wanted clean the behind front glass where the spot is, so little bit worried about that central piece - will it somehow decenter if it fells off ? The large front element and one smaller element stuck to it can be removed as one piece when that retaining ring is unscrewed. These pieces are fairly thick and heavy. The rest stays in place when I tip the lens on its side. When I put the elements back into place, they seat solidly in place; I can't shift them at all. So I think decentering is not likely from misplacing that element. What fell off on my lens is just a cosmetic plastic cap.

02-20-2015, 02:40 PM	#25
manntax Veteran Member Join Date: Jan 2012 Photos: Albums Posts: 1,972	Originally posted by Just1MoreDave The large front element and one smaller element stuck to it can be removed as one piece when that retaining ring is unscrewed. These pieces are fairly thick and heavy. The rest stays in place when I tip the lens on its side. When I put the elements back into place, they seat solidly in place; I can't shift them at all. So I think decentering is not likely from misplacing that element. What fell off on my lens is just a cosmetic plastic cap. Thank you - you have been very helpful - I will give it a go and be done with that annoying patch of fungus :P ---------- Post added 02-20-15 at 09:41 PM ---------- Originally posted by Jean Poitiers I have not attacked my 55BB due to lack of time and really having very little fungus worth the intervention IMHO. I also later acquired a 55B which I like better due to its collar (etc.) and use it the most. I do not know if my spanner will "fit" the job (go wide enough). If not then I need to look at my other available tools (the big caliper) ... let me look at this again over the weekend and I will get back to you. Salut, J Thanks for letting me know - I might be brave enough to do it this weeked anyways - looks to be fairly easy as per advice I got from Just1MoreDave

10-09-2017, 07:04 AM - 1 Like	#27
fwcetus Site Supporter Join Date: Sep 2006 Location: New England Photos: Gallery \| Albums Posts: 1,286	Originally posted by grahame 55bb is one of best mirror lens out there. definitely worth rescuing it. The 55BB is definitely a superb (and, even with some higher market prices lately, relatively inexpensive) 500mm mirror lens, as grahame and others have stated. [And the 55B is no slouch, either.] As for attempting to perform a supposedly minor lens repair or CLA, I personally have ruined enough lenses to finally learn that I myself should never ever try to do either again.