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04-25-2010, 08:25 AM   #1
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quantaray 100-300mm vs 70-300mm?

Does anyone have any experience with either of these. I already have the 100-300 shown here. Third-Party Lens Review Database - Quantaray 100-300mm F4.5-6.7 LDO

I can get the 70-300 cheap (if I act fast only).

I do not know which version it is (I suspect the tamron version but I do not know for sure).

I understand the quality is not pro but cheap glass Is all I can afford right now. My only major issue with the 100-300 that I already have is the autofocus sucks. I have a vision problem that makes manual focus an issue. The 100-300 has focus issues at higher magnification, even in daylight. Low light focus sucks and forget about using a teleconverter. Right now I have to take several shots in manual focus (at different focus points) and then find the in focus one later on the computer.

As best as I can tell the 70-300 is supposed to have a bit better AF. Of course its always hard finding info on quantaray stuff.

So does anyone know how they compare?

One a side note, I'm only concerned with its performance on the long end. I have several other lenses with less magnification including a 80-200m pentax brand lens.

09-19-2010, 06:15 PM   #2
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I'm actually very interested in these 2 lenses too. Which should I get? 100-300mm or 70-300mm?
09-20-2010, 09:18 AM   #3
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The 100-300 is half a stop slower than the 70-300's, and the 70-300's have more range and tend to be all pretty highly rated. I think you'd have to be getting the 100-300 for close to free to be worth even a second look. But do see the many existing threads comparing the various 70-300's as well as the Pentax DA telephoto zooms for more.
09-20-2010, 11:25 AM   #4
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I spontaneously bought the 100-300mm last night lol. It was the only listing on ebay, and it was ending soon. I got it for $65. From pics I've seen, it looks sharper to me than the 70-300mm. I don't mind the aperture too much, I'll probably only be using it in bright daylight. Until I can save up for the 55-300mm da-l.

09-20-2010, 12:26 PM   #5
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The Tamron 70-300 version (To figure out which one you're getting as Quantaray-branded, look at the specs for matching filter size and physical dimensions) is excellent - I have a Quantaray-branded Tamron and I used it all the time until I bought a Bigma.
09-20-2010, 12:46 PM   #6
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I'm not one to turn to for technical specs, sharpness figures, comparison's between this lens and x lens, so instead just look at some of the pictures I've taken and judge for yourself! :-)

Images taken with my Quantaray 70-300 (Sigma version according to EXIF):


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