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12-02-2020, 12:00 PM   #1
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Vivitar 500mm - Replace Front Lens / All Lenses?

All,

I have a Vivitar 500mm f/6.3 (this one: Vivitar Tele-Vivitar 500mm F6.3 Lens Reviews - Vivitar Lenses - Pentax Lens Review Database) which is really a solid lens.

Its performance is decent, esp. when I can find the right focus.

But here's a question: has anyone ever considered upgrading / refurbishing such a lens with newer / better glass? I was thinking of something multi-coated - perhaps a telescope lens or something like.

I suspect I would need some way to measure the diameter and FL of the current lens. Thoughts?


Last edited by jawats; 12-02-2020 at 12:25 PM.
12-02-2020, 12:11 PM   #2
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I mean people have made their own telescopes so it could be possible. Getting multicoatings would make it pretty cost prohibitive though I would think.
12-02-2020, 01:07 PM   #3
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Your lens seems pretty uncommon jawats, the 600mm f8's are more often found. These are all telephotos: there is a matched second group that makes a negative optical unit, increasing the effective focal length. IMO you are most unlikely to find a achromat/apochromat objective that matches the spec and diameter of the existing one, which is probably pretty high quality (these were the premium long lenses of the 1960's), except as a way too pricy custom order. The optical performance is broadly speaking limited by the simple design I think. If you search there are some good pics taken with an apo telescope in the 300mm lens club, about 5 yrs ago...? My own digiscoping experiments have been unrewarding but eyepiece projection is different to using a telescope simply as a lens.

I have been idly thinking about trying to do the same thing for my novoflex - this is a design that is just an objective. I have a 600mm optic but it's not in very good condition, scratched and coating loss, so experimenting with an alternative objective could be fun, maybe something ex WD, approx similar focal length? I have a fair amount of latitude for fitting something, the optics unscrew into segments and I have a "B" stock with bellows so big focus range. Anyone out there with potential sources of suitable optics?
12-02-2020, 03:35 PM   #4
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Overall, I don't think it would be anywhere close to being worth the effort. If the existing lens is coated at all, there's not much to be gained (though some) with multicoatings. Changing the actual lens element is very hit and miss at best assuming you could find a replacement (per what marcusBMG stated), and if the lens was designed for image quality, chances are any substitute would wander away from that. You'd have to be an optical engineer to improve the lens performance based on another choice of the front element - maybe. Just making sure the existing lens is clean and free from dust, mold, etc., will probably be the best you can do for getting the most out of your lens.

12-03-2020, 08:18 AM   #5
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QuoteOriginally posted by marcusBMG Quote
Your lens seems pretty uncommon jawats, the 600mm f8's are more often found. These are all telephotos: there is a matched second group that makes a negative optical unit, increasing the effective focal length. IMO you are most unlikely to find a achromat/apochromat objective that matches the spec and diameter of the existing one, which is probably pretty high quality (these were the premium long lenses of the 1960's), except as a way too pricy custom order. The optical performance is broadly speaking limited by the simple design I think. If you search there are some good pics taken with an apo telescope in the 300mm lens club, about 5 yrs ago...? My own digiscoping experiments have been unrewarding but eyepiece projection is different to using a telescope simply as a lens.

I have been idly thinking about trying to do the same thing for my novoflex - this is a design that is just an objective. I have a 600mm optic but it's not in very good condition, scratched and coating loss, so experimenting with an alternative objective could be fun, maybe something ex WD, approx similar focal length? I have a fair amount of latitude for fitting something, the optics unscrew into segments and I have a "B" stock with bellows so big focus range. Anyone out there with potential sources of suitable optics?
Edmund Optics seems like a good site, still, but also expensive once you get larger / specialized.

---------- Post added 12-03-20 at 08:21 AM ----------

QuoteOriginally posted by ZombieArmy Quote
I mean people have made their own telescopes so it could be possible. Getting multicoatings would make it pretty cost prohibitive though I would think.
I suspect you're correct - and this lens may already be better than most things I could buy at a worthwhile price point.

---------- Post added 12-03-20 at 08:22 AM ----------

QuoteOriginally posted by Bob 256 Quote
Overall, I don't think it would be anywhere close to being worth the effort. If the existing lens is coated at all, there's not much to be gained (though some) with multicoatings. Changing the actual lens element is very hit and miss at best assuming you could find a replacement (per what marcusBMG stated), and if the lens was designed for image quality, chances are any substitute would wander away from that. You'd have to be an optical engineer to improve the lens performance based on another choice of the front element - maybe. Just making sure the existing lens is clean and free from dust, mold, etc., will probably be the best you can do for getting the most out of your lens.
Free from dust and mold, indeed!

Also, trying to get to infinity has been difficult, but that's a horse of a different barrel of monkeys.
12-03-2020, 12:11 PM   #6
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In re-reading your original post, I may have misunderstood your intent. Are you talking about working over the lens you have (refurbishing) or getting a completely new lens with better performance? If the latter is the case, there are a lot of good choices out there depending on how much you plan to spend.
12-04-2020, 08:24 AM   #7
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QuoteOriginally posted by Bob 256 Quote
In re-reading your original post, I may have misunderstood your intent. Are you talking about working over the lens you have (refurbishing) or getting a completely new lens with better performance? If the latter is the case, there are a lot of good choices out there depending on how much you plan to spend.
A completely new lens with better performance. What are you thinking?

12-04-2020, 09:24 AM   #8
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QuoteOriginally posted by jawats Quote
A completely new lens with better performance. What are you thinking?
When you said "refurbish", I (and apparently some others) were thinking you were talking about reworking or replacing lens elements in your existing lens. Now your post makes a lot more sense if you are just talking about finding a lens replacement for the telephoto mentioned.

I'm not sure if it's available anymore, but I have the Sigma 55-500mm zoom lens, which you might consider (even used). It has good coatings and performs pretty well for a zoom (particularly around 300mm but not so well at the full 500mm), and it gives you the advantage of a range of telephoto powers all in one lens. It's just as fast as your existing lens and I think the 500mm performance would be comparable. It's main downside is its size and weight but that's par for the course in a telephoto.

Last edited by Bob 256; 12-04-2020 at 09:29 AM.
12-04-2020, 11:50 AM   #9
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QuoteOriginally posted by Bob 256 Quote
When you said "refurbish", I (and apparently some others) were thinking you were talking about reworking or replacing lens elements in your existing lens. Now your post makes a lot more sense if you are just talking about finding a lens replacement for the telephoto mentioned.

I'm not sure if it's available anymore, but I have the Sigma 55-500mm zoom lens, which you might consider (even used). It has good coatings and performs pretty well for a zoom (particularly around 300mm but not so well at the full 500mm), and it gives you the advantage of a range of telephoto powers all in one lens. It's just as fast as your existing lens and I think the 500mm performance would be comparable. It's main downside is its size and weight but that's par for the course in a telephoto.
Bob,

That's a good idea! I have the Tamron 70-200 A001, but for astro, bird, etc. performance, it's not the best.
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