Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
12-22-2010, 05:45 PM   #1
Senior Member
Damian's Avatar

Join Date: Aug 2010
Location: United States
Photos: Gallery | Albums
Posts: 267
Pentax-F 70-210mm question

Is the Pentax-f 70-210 f4-5.6 an internal zoom lens? Meaning does it extend when zoomed or stay the same size? Does it extend when focusing?

I'm looking for a new candidate for stacked lens macro shooting. I need a good quality zoom lens that does not extend when zoomed. Focus extension is ok, but internal focus would be awesome.

12-22-2010, 07:17 PM   #2
Administrator
Site Webmaster
Adam's Avatar

Join Date: Sep 2006
Location: Arizona
Photos: Gallery | Albums
Posts: 43,259
Nope. Don't expect IZ from non-star lenses!

Adam
PentaxForums.com Webmaster (Site Usage Guide | Site Help | My Photography)



PentaxForums.com's high server and development costs are user-supported. You can help cover those costs by donating. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

12-22-2010, 07:52 PM   #3
Senior Member
Damian's Avatar

Join Date: Aug 2010
Location: United States
Photos: Gallery | Albums
Posts: 267
Original Poster
Darn. Oh well. Any other suggestions anyone? Doesn't have to be Pentax, could be another brand. Anything with an 'A' setting. I currently own a slide zoom with internal zoom, but I'm looking for something sharper then what I have. FYI: I have a Kiron 80-200 f4.5. I'd prefer something faster, but sharper is good enough. Not to say the Kiron isn't sharp, just that it isn't sharp enough.

Thanks in advance.
12-23-2010, 12:51 PM   #4
Pentaxian
Just1MoreDave's Avatar

Join Date: Feb 2007
Location: Aurora, CO
Photos: Gallery | Albums
Posts: 4,864
QuoteOriginally posted by Damian Quote
Is the Pentax-f 70-210 f4-5.6 an internal zoom lens? Meaning does it extend when zoomed or stay the same size? Does it extend when focusing?
It gets about 40% longer when zoomed, maybe another 20% when focused.

I think the F100-300/4.5-5.6 was internal zoom, but I've sold it and can't check my memory. It only got slightly longer when focused too.

12-23-2010, 06:49 PM   #5
Pentaxian




Join Date: Oct 2006
Location: Chicago suburb, IL, USA
Posts: 1,535
Hi Damian,

If you're looking for something in this FL range, I'd be looking at the A 70-210 f4, an "A" capable version 3 (Komine) Vivitar Series 1 70-210 f2.8-4, or a Tamron SP 70-210mm F/3.5 Model 19AH. The Pentax is probably the most common, and will probably be the cheapest to purchase by quite a bit. The Tamron is more rare, but still can be found, the Komine/Vivitar is pretty rare, and even rarer in the "A" configuration, plus they are very sought after, so the price is usually relatively high.

You can read the reviews for the Pentax (and the others too I assume) from the database:

https://www.pentaxforums.com/lensreviews/SMC-Pentax-A-70-210mm-F4-Zoom-Lens.html

Here are some links to info on the Viv and Tamron:

http://www.robertstech.com/vivitar.htm

Tamron SP Adaptall-2 70-210mm F/3.5 Model 19AH

The Pentax is no slouch. It probably is very comparable to the F 70-210 you mentioned in your original post. I have one of these, and it will always be part of my permanent collection.

If size and weight is not a problem, then I'd also consider the Tamron SP 80-200mm F/2.8 LD Model 30A.

Tamron SP Adaptall-2 80-200mm F/2.8 LD Model 30A

I have one of these, and it's a superb lens. For this or the previously mentioned Tamron, you would also need an Adaptall 2 PK/A adapter, and these are relatively rare and expensive now, but worth it, especially if you can see uses for some premium MF lenses at relative bargain prices.

All of these are "one touch" zooms, which means that you slide the focus ring to zoom and the lens does not change length.

Scott

Last edited by snostorm; 12-23-2010 at 06:57 PM.
12-23-2010, 10:00 PM   #6
Senior Member
Damian's Avatar

Join Date: Aug 2010
Location: United States
Photos: Gallery | Albums
Posts: 267
Original Poster
QuoteOriginally posted by snostorm Quote
All of these are "one touch" zooms, which means that you slide the focus ring to zoom and the lens does not change length.

Scott
Thanks for your input Scott. You've made some pretty good suggestions, and I've been looking at most of those as candidates. Specifically the Pentax 70-210 f4. The Tamron 70-210 f3.5, although it is a lens I would like to pick up simply for it's IQ, will not work for my purposes as it extends when zoomed. That particular lens, and indeed most tamron SP one touch zooms, were designed as extension type zoom lenses.

The Komine / Vivitar, is one that I would love to nab, but as you mentioned, they are very rare and usually quite expensive.

I hadn't considered the Tamron SP 80-200 f2.8. I had a chance to pick one up a while back but didn't because the seller was a little sketchy on getting me pictures of the "light fungus" that infected the front element. Would have been a great bargain but I'm not about to inherit another lens with fungus that I do not have the time to learn how to fix. So I'm curious, does the Tamron 80-200 f2.8 extend when zoomed? Doesn't look like it from the pictures.

Another question you might be able to help with, are any of the suggested lenses, specifically the Pentax 70-210 f4, the tamron 80-200 f2.8 and the lens sugested in the previous reply by Just1MoreDave the Pentax F100-300, Parfocal lenses?

To get a better idea of the why behind all this check out my comment on another post regarding revers macro setups Here

Just so you know, my wet dream would be a lens that is both internal zoom and internal focus. Doesn't necessarily have to be a slide zoom. Not that it matters that much, but zoom creep sucks if you have everything just the way you want it and the thing starts sliding down on you. It would also be helpful if the front element of the lens in question is a manageable size so i can easily revers a fast wide prime in front of it.

Again, thanks for your help and your great suggestions.
12-23-2010, 11:46 PM   #7
Pentaxian




Join Date: Oct 2006
Location: Chicago suburb, IL, USA
Posts: 1,535
Hi Damian,

Both the A 70-210/4 and the Tamron SP 80-200/2.8 extend when focused, but not when zoomed.

As far as I can tell, both are parfocal. It's hard to be precise with my Tamron because it needs a CLA as the zoom/focus ring is a bit sticky at the short end. I really only use it towards the long end, so this has been a problem that I've largely neglected.

I've never tested either for this formally, all I know is that with the A70-210/4, if I'm careful not to rotate the collar, I can slide it from 210 to 70 and maintain a focus confirmation on any of my bodies. If the Tamron changes focus, it's by a very small amount, but with the stickiness, I can't tell if I'm rotating the collar as I slide it, so I'm just not sure. FYI, the A70-210/4 is known for zoom creep, but IIRC, you can peel back the rubber cover and adjust this with some screw(s) underneath on the ring. Mine does not creep at all.

The A70-210 takes a 58mm filter and the Tamron takes a 77mm.

Hope that helps. . .

Just FYI, I use a Sigma EX 180/3.5 DG APO Macro with a Pentax F 1.7x Auto Focusing Adapter and a Metz 15 MS1. This gives me @ 1.9:1 at about 10" from the front element, and 1:1 at @ 15". I like to shoot Jumping Spiders, and this setup allows me to shoot them handheld from far enough away that I don't seem to intimidate them at all. Also I get pretty good DOF at 1:1 because of the increased lens to subject distance. BTW, I also use AF-C to focus. I don't get the crazy magnifications you can get with reverse stacked lenses, but I have a lot of fun. . .



Scott
Attached Images
View Picture EXIF
PENTAX K20D  Photo 

Last edited by snostorm; 12-24-2010 at 12:39 AM.
12-24-2010, 09:09 AM   #8
Senior Member
Damian's Avatar

Join Date: Aug 2010
Location: United States
Photos: Gallery | Albums
Posts: 267
Original Poster
Scott,
Again, thanks for your input and the good information. I have a couple of macro lenses that I shoot with. A Sigma 50mm f2.8 1:1 macro and a Tamron 90mm f2.5 1:2 macro. I love them both, just wish the tamron would do 1:1 without the extension tubes or 01F 2x TC. I've experimented a bit with stacked TC's and extension tubes and can get down pretty far that way, but the CA can get pretty bad with to many TC's. I've done some reverse macro at 4:1 but I'm not completely satisfied with the quality I'm getting. I have some really good primes so I think the problem may be with my zoom. Not that it's bad by any means, just not great.

I'm going to look around some more and see what I can find. Just wondering, do you happen to know if any of the non-SP tamron adaptall's are Parfocal. There are some decent 70-210 f3.8-4 that are internal zoom slide zooms out there that might be contenders. Specifically the model 46A. It seems to have better resolution charagteristics with only slightly lower contrast then the 19AH that everyone loves.


Thanks again for your help.

Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
focus, k-mount, lens, pentax lens, pentax-f, pentax-f 70-210mm, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: Pentax SMC-A 70-210mm f4 Macro zoom; Pentax A3000 film SLR; Vivitar 28-210mm z NeverSatisfied Sold Items 9 05-14-2010 01:37 PM
Compare the lens coating of Takumar-F 70-210mm and smc Pentax-F 70-210mm jcdog2006 Pentax SLR Lens Discussion 13 02-19-2010 08:16 AM
Pentax A 70-210mm built-in lens hood question manteiv Pentax SLR Lens Discussion 7 12-20-2009 10:55 PM
Question SMC Pentax-F 70-210mm F4-5.6 netuser Pentax SLR Lens Discussion 9 12-13-2009 05:08 PM
Tamron 35mm-210mm Macro Question kwetiaw Pentax Film SLR Discussion 4 10-04-2009 08:16 PM



All times are GMT -7. The time now is 01:44 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top