From: ka1gt@cbnewsm.cb.att.com (robert.m.atkins)
Subject: Re: Telephoto zooms revisited
Organization: AT&T
Distribution: na
Date: Mon, 5 Oct 1992 16:24:28 GMT
Keywords: telephoto, lens

In article <1992Oct2.231352.3934@houston.dolphin.com>, Norman_Furlong@dolphin.com (Norman Furlong) writes:
> 
> 	1) Price -- I'll spend $500 on a lens that will last twice as  
> long, hold its resale value OR be noticably "better" (sharper, more  
> contrast, less vignetting, less aberation, etc.) than a $250 lens, but  
> cannot afford the $900 Minolta APO in *any* case. :-(
> 	2) Quality -- how much credence should I put in Sigma or Tokina's  
> APO lenses?  Does it fall somewhere between Minolta's regular and APO  
> lenses in quality?
> 	3) Speed -- In shooting outdoors, will that extra stop of light  
> make a big difference, given the details above? 
> 	4) Maximum focal length -- in what situations will I be missing  
> the 300mm length at 5.6 that I can't make up for with a 1.4x teleconverter  
> on my 70-210i zoom (300/f6.3) or 80-200 APO (280/f4).  And would the  
> degradation of the teleconv. pretty much cancel the advantages of the  
> 80-200/2.8 APO, leaving the equivalent of a (hypothetical) Sigma 280/f4 in  
> quality, or am just *way* off base here?
> 	5) Service -- Am I going to get better service, having bought a  
> Minolta lens, verses another if I buy at a retail store?  If I buy mail  
> order?
> 	6) Resale value -- How well will the Sigma/Tokina lenses hold  
> their value compared to the Minolta?
> 	7) Durability -- I do shoot mostly outdoors.
> 	8) Weight -- I fly frequently and occasionally go backpacking, so  
> lugging around a heavy lens would be burdensome.
> 

The answer to your question is .....42...., but more seriously it is
"It all depends". If there were hard and fast rules, there wouldn't be a
choice to make between dozens of lenses. You have to trade off what is
important TO YOU, against what isn't. Does an extra stop make a big
difference - it all depends on what and when you shoot. If you shoot
landscapes, it probably doesn't. If you are a dawn/dusk nature photographer
it does. Weight? how much are you prepared to suffer for quality? I know
of photographers who will backpack 20-30lbs of equipment for the sake of
quality, other may draw the line at 5lbs. Cost? How much money do you have
and what level of quality satisfies you. With very few exceptions, the
camera manufacturers lenses are better (and often more expensive) than
Sigma, Tokina, Tamron etc. In general you do get what you pay for. This
is especially true for long telephoto lenses and very wide angle lenses.
Durability? varies on a lens by lens basis, but in general the manufacturers
lenses are though to hold up better - many Nikon uses swear by their
durability. Older, metal, MF lenses may be more durable than their new,
plastic, AF counterparts. Resale? No dealer will offer you more than about
50% of the purchase price for a lens, often much less. Private sales
are better. A good (read expensive) lens will usually hold better value than
a cheap lens. Focal length? What do you shoot. If wildlife photography is
high on your list, 200mm is too short much of the time. Even 300mm is often
too short. A good 200mm lens + 1.4x converter may equal a fair 300mm lens.
It won't be as good as a good 300mm lens, and if the 200mm is a zoom then
all bets are off. Many zooms do not work well with converters. Sharpness?
If you want to sell pictures they had better be SHARP! Unless they are news
photos a blurred picture is useless. Shapness costs money (and technique)
and again you have to make the trade off of cost vs. performance.

In summary I would rate cost and sharpness highest, followed by weight,
aperture, durability and resale value. I would buy a manufacturers lens
over an eqivalent 3rd party lens. I'd also buy Nikon or Canon, but that is
a whole different story.....

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Bob Atkins  AT&T Bell Labs  email (direct)  att!clockwise!rma
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