Canon 800mm f/5.6 FD front glass

[lituramentico]

<p>I found for sale Canon 800mm f/5.6 FD, but unfortunately the seller describes the lens with missing front glass. The seller means (protecting) glass not magnifying glass, and claims that it does not affect the quality. I cannot see the the lens and that's why would like to ask if there is a such a thing "protecting glass" that comes originally with this kind of big canon lenses.<br>

I am about to pay $1k for the lens.<br>

Thank you!</p>

 

[dave_s]

<p>Pass. Irrespective of lens performance, the missing glass tells you someone has been hard on the lens, or has been monkeying around with it. I would avoid it unless it were <em>deeply</em> discounted.</p>

<p>Is it a bargain, in any case? No. Even in the 2002 - 2005 era, the plain-vanilla 800/5.6 sold for about $1250 on ebay, according to <a href="http://home.comcast.net/~starka/CanonFD_ebay2.htm">Vladimir Antonov's data.</a> Odd lenses like this hold their value better than the common consumer lenses, but $1000 sounds like an OK price if it were a good user, IMHO.</p>

<p>Does the 800/5.6 have a flat front glass? The <a href="http://www.mir.com.my/rb/photography/companies/canon/fdresources/fdlenses/6800mm.htm">Malaysian FD site</a> shows a block diagram of the 800/5.6 'L' version with an apparently flat front glass. I don't know whether the regular 800/5.6 has a similar protective glass, but someone here will know.</p>

[rick_janes]

<p>Lu, there are three FD 800/5.6 types in all. The first two used the original Canon breech-lock: a standard S.S.C. model and an "L" with one ultra-low dispersion element. The "L" was eventually given a New FD style bayonet mount in its third and final version. All three are very similar in appearance and should not be confused with the entirely different FL 800/8 which required a separate focusing unit!<br /> I've read that the first element in many L super-teles is partly intended to protect the more easily damaged and expensive UD glass or fluorite (!) lenses behind it. But is that to say it serves no optical purpose whatsoever? Hmmmm.<br /> My EX+ New FD 800/5.6L cost ~$1300 back in '09, complete with case, caps, and hood- first glass element too! $1000 doesn't sound like a great bargain for a non-L even if it were complete. Resale value of a damaged lens is usually low so if you're not happy with it, good luck.<br /> Nice ones are not found everyday but be patient and by all means wait for an "L".</p>

[lituramentico]

<p>Thank you guys. It seems it is not a good deal. I think Rick made very good point about the purpose of the front glass. However I changed my mind and won't spend money for this lens. Thank you again, for your responses.</p>

 

[hang_chung]

<p>1.800/5.6 L (both breech lock & bayonet versions) has protective front glass. <br />2.800/5.6 SSC has not. <br /><br />If the seller is correct about "missing front glass", he/she should be referring to L version. <br /><br />For FD lenses, flat/protective front element is exclusive for L lense only. The reason for adding this is because UD/FLOURITE are much prone to scratches than "normal" glasses. Without that front element its easy to damage the UD/FLOURITE glass while cleaning</p>

[awahlster]

<p>the flat glass would be factored into the lens formula just like having to have a filter in the optical path to have everything as designed.</p>

<p>I wouldn't touch said lens with a 10 foot pole.</p>

<p>PASS on it find a complete example.</p>

[hang_chung]

Mark, you're right if you're talking about rear filter mechanism, but not for front protector like the one you'll find on L lense.

Flat clear protecting element <strong>in front of </strong>all refractive glasses has no effect on the optical path at all (except some theoretical loss in optical quality), Just the same as you adding a screw-in protecting filter on you lenses.

[rwbowman]

<p>FWIW, KEH is now listing an FD 800mm 5.6L in EX condition for $1599. (Disclaimer goes here.)</p>

[lituramentico]

<p>So is it fair to say that without the flat protecting glass, this lens has a short lifespan? 1-2 years perhaps?...</p>

[hang_chung]

Some earlier designs like CANON FD 300/2.8 SSC Flourite also has a exposed flourite element, and they still apear on the market like ebay/B&H after almost 40 years, so judge it by yourselves

[rick_janes]

<p>Hang Chung, where did your information come from regarding the exposed fluorite element? I ask because I am extremely skeptical!<br>

Canon's first two fluorite lenses, the FL-F 300/5.6 and FL-F 500/5.6 of 1969, didn't expose these special elements.</p>

[kevin_omura]

<p>Guess the logical thing to do would be to contact Canon and see if for some reason they still have one of these elements in stock and then find out how much it is. Granted if the seller was smart enough they would have just put a new one on that lens and increased it's resale value. </p>

[lituramentico]

<p>Kevin, it won't work.... And it is not worth it ... I already made my mind not to buy this glass. I would rather spend a bit more and get the intact lens. But thanks for the advise!</p>