Another "which lens" question! Yay!

[andrewg_ny]

<p>I assume you don't really mean 'IF'--what IF gives you is a front element that doesn't rotate (good for using polarizers).</p>

<p>What you might be thinking of is 'internal zoom' but that's a relatively rare feature. One nice lens that offers it is the DA* 50-135/2.8. Another is the very compact, dirt-cheap, optically pretty good Pentax-F 80-200/4.7-5.6. The internal zoom is a good feature but on my copy the zoom & focus aren't particularly smooth.</p>

<p>Most of the modern AF telezooms will extend significantly, probably close to double their 'travel' length. The designed-for-digital 50-200 lenses are significantly more compact than the xx-300 lenses, and usually take 49 or 52mm filters, while the xx-300 lenses generally take 58mm filters and are noticeably larger and heavier. Also, minimum focus is typically 1.1m for a xx-200mm lens but 1.5m for xx-300. (Yes, some like the Sigma and Tamron offer special macro modes which decrease this distance at the long end of the focal range, but this is of little help if you're taking a close-up portrait at 70-100mm).</p>

<p>In addition to probably offering the best IQ of its class (before you commit to double the price and weight to get a Pentax DA* lens or Sigma 70-200/2.8), Pentax's 55-300, being designed-for-digital is also probably the most compact of the xx-300 lenses. I haven't handled the DA-L version but the metal-mounted DA version seems pretty well-constructed.</p>

<p>The Quantaray/Phoenix lenses are probably rebadges of the non-APO Sigma or Tamron. The Tamron and Sigma have similar specs but close comparison may betray the lenses origin.</p>

<p>The older Pentax-F 70-210/4-5.6 ED falls somewhere in between the 50-200 and xx-300 class--designed for film so it's a bit heavier, slightly larger than a 50-200 but is pretty nice if you don't need the 50-70 range or zoom to 300mm.</p>

<p>Your post doesn't make it real clear whether this is in addition to a shorter lens or not--if you're up close, I imagine there might be some shots you'll want that you won't be able to take with a telephoto zoom.</p>

[phyliss_crowe]

<p>The Tokina 70-210 went back; had an issue I wasn't made aware of.</p>

<p>I can't afford just about any f2.8 lens. What about the Pentax-A 35-105 f/3.5 or the Pentax-F 35-135 f3.5-4.5? Both get high marks across users, almost neck and neck. I know the all metal and glass 35-105 is heavier, but I've used a chest pod before with no issues. I've been all over flickr and other sites this weekend looking for indoor shots from these lenses but didn't find a whole lot.</p>

<p>For the wide end, I have the Pentax 18-55mm II - MUCH happier with it than version 1 - a Tak 28 f3.5, a Komine Vivitar 28 f2.8, and a Tak 55 f1.8.</p>

[phyliss_crowe]

<p>Well, I’ve now purchased my 3 lenses for this event.</p>

<p>First, I got a EOS compatible Tokina “AF Aspherical” 28-105 f3.5-4.5 (no aperature ring) for my son’s girlfriend’s Canon 7D. She hasn’t had it but a couple days so hasn’t shot anything with it yet, but she is thrilled at the focal length, and size and weight of the lens.</p>

<p>For my son, we got a Sigma “Aspherical” 28-105 f2.8-4 (Geez, Grandma. What BIG front element you have!). He, too, hasn’t had time to play with it much, but what little he has used it to-date, he likes it overall very much, except the difficult-to-get to aperture ring.</p>

<p>For me, I first got a Kobori (77xxx) Vivitar 35-105 f3.2-4. Did have to dremel the baffle off so it would mount on my K200D, it suffers from very slow zoom creep, and it flares at times. But it came with a nice rubber lens hood that stops that. As usual, very impressed with color, sharpness, bokeh, handling, and petite size of this lens. It, and my Kobori Vivitar 70-150, are permanent keepers.</p>

<p>However, I maintained that I really should have an auto focus lens for this event so I can remove that step from the shooting equation. And today, I won an all-black version of the Pentax FA 28-105 f4-5.6 IF (the rebadged Tamron with blue numbers, not the longer, bigger, heavier black model). I know, I know. I was dead set against Tamron because of frequent reports of PF issues from their lenses.</p>

<p>But after seeing Bong Manayon’s evening and night photos at Flickr that he made with this lens and learning that several of his photos have made it into the Pentax Photo Gallery, I figured I couldn’t possibly go wrong buying it. Since I first posted this question, I’ve gotten some respectable shots at our zoo’s night creatures exhibit (simulated moonlight) at f4 so I’m confident this Pentax will have no trouble with this event’s lighting.</p>

<p>Oh, and I sold my older Sigma 70-300 APO in favor of the new Sigma 50-200 DC OS HSM that was on my list (Someday, Sigma will deplete the alphabet. I can just feel it.). Sweet lens! The auto focus is so quiet, I at first thought I'd forgotten to switch to it!</p>

<p>Thanks one more time for all your input! Highly valued and very helpful!</p>