Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
05-23-2011, 11:29 AM   #16
Site Supporter
K57XR's Avatar

Join Date: Feb 2011
Location: Colorado, USA
Posts: 813
QuoteOriginally posted by MK-x Quote
There is a "lock" button on some of zoom lenses. Is it used to lock the lens while in bag only, or the lens can be locked in any position (zoom extension)?
For the DA18-250mm you can only lock at wide angle (18mm). To prevent lens creep at different focal length you will either have to manually hold the zoom ring in place or like mentioned above, a tape or something. And yes, the DA18-250mm (which is a re-badged Tamron 18-250mm)is an excellent lens, IMO.

05-23-2011, 12:12 PM   #17
Forum Member




Join Date: May 2011
Photos: Gallery
Posts: 93
Original Poster
QuoteOriginally posted by K57XR Quote
And yes, the DA18-250mm (which is a re-badged Tamron 18-250mm)is an excellent lens, IMO.
What differences are there between 18-250 and 18-200 (except the focal length)? The price difference is almost twice.
05-23-2011, 02:03 PM   #18
Pentaxian
Marc Sabatella's Avatar

Join Date: Sep 2006
Location: Denver, CO
Photos: Gallery
Posts: 10,686
See the lens reviews on this site (start by clicking "lenses" on the menu above) or opinion on those or other specific lenses. the 18-250 is newer and better and pretty much replaced the 18-200, which is why the latter is so much cheaper.
05-23-2011, 02:51 PM   #19
New Member




Join Date: May 2011
Posts: 10
Tamron vs. Sigma superzooms

I am brand new to Pentax, having been a Nikon user for years. I just purchased a K-5 and just love its performance and feature set.

I have tried both the Tamron 18-200 and the Sigma 18-250. In general, the Sigma is a much better lens in terms of build quality, lens creep and usability.

However, one issue I am having with the Sigma is that the lens type does not show in any software have tried, including Lightroom 3.3 and EXIFTool. I use the Lens type for a lot of filtering in Lightroom. In addition, Lightroom has a lens proifile for the Sigma 18-250 for automatic lens corrections, but since the EXIF data is either missing or not decipherable, I cannot use this feature without manually setting the lens type.

Can anyone help with this issue?

05-23-2011, 05:41 PM   #20
Veteran Member
RioRico's Avatar

Join Date: Jun 2008
Location: Limbo, California
Posts: 11,264
Responding to more of MK-x's questions (that haven't been excellently answered already):

ZOOM CREEP: Yes, the lock button on the 18-250 only locks it in the widest (18mm) position. I can't comment on whether other modern superzooms show zoom creep, 'cause I haven't tried them -- see the reviews. I did have a Tamron 28-200 that didn't creep IIRC. A number of older manual push-pull IF (internal focus -- they don't change length) zooms do show zoom creep, without locking buttons. Many shorter zooms DON'T creep. Again, read the reviews of any specific zoom.

TAMRON REBATE: I bought a new Tamron 10-24 a few months ago to exploit a US$100 rebate, so it only cost me US$375, shipped! I bought it online from a USA store (maybe Adorama, I don't recall) and had it shipped to a USA address. My citizenship was not questioned. Any store that sells a rebated item should have a prominent link to the terms of the rebate. I can't check the details now because I'm away from home for a couple months. But IIRC the only requirements were proof of purchase, and submitting the rebate before its expiration.

LOW-LIGHT SUITABILITY: Strictly speaking, almost any lens *can* be used in low light, but maybe only certain conditions would allow sharp shots, like tripodding and stabilizing a creeping or large lens. Yes, I have had to wrap my Rubinar Makpo 1000/10 mirror in sandbags atop a tree trunk in order to get blur-free shots. A 'slow' lens just doesn't allow a fast shutter at low ISO; so, slower lenses are less suitable than faster lenses. Yes, I have used my DA18-250 handheld at f/5.6 at ISO 6400 zoomed-out, to get a shot; convert it to B&W for that dramatic "pushed Tri-X" look, eh? With a 200/2.8 lens, I could have used ISO 1600, for much less noise.

MANUAL LENS AVAILABILITY: Yes, most manual lenses are on the used market. As mentioned, some new Leitz (expensive) and Samyang (under various names) manual lenses are available. So are some that may be out of production, but are sold NIB (New In Box) from older stock. I got a NIB M42 Hanimar Preset 135/3.5 for under US$20 a couple years ago on eBay, shipped from China, and have seen the same in more recent listings. I got an incredible Schneider Betavaron 50-125 zoom from a liquidator on eBay who was selling off their old stock of new lenses -- it cost me US$72 shipped, marked down from US$3500! But most available manual lenses now are used.

Last edited by RioRico; 05-23-2011 at 06:55 PM.
05-23-2011, 11:04 PM   #21
Forum Member




Join Date: May 2011
Photos: Gallery
Posts: 93
Original Poster
QuoteOriginally posted by Eliglass Quote
I have tried both the Tamron 18-200 and the Sigma 18-250.
One of Pentax lens' functions (as written in a table I've attached earlier) is "Automatic obtaining of lens focal length" (for SR). Do Tamron and Sigma lenses support this feature (and does it actually work with the camera)?

RioRico - thanks.
05-23-2011, 11:27 PM   #22
Forum Member




Join Date: May 2011
Photos: Gallery
Posts: 93
Original Poster
It seems that Sigma lenses have Image Stabilizer, which (I guess) makes the price higher. Too bad they don't have the same model without it.
05-24-2011, 12:16 AM   #23
Veteran Member
Frogfish's Avatar

Join Date: Dec 2009
Location: Shanghai
Posts: 4,490
QuoteOriginally posted by Eliglass Quote
I am brand new to Pentax, having been a Nikon user for years. I just purchased a K-5 and just love its performance and feature set.

I have tried both the Tamron 18-200 and the Sigma 18-250. In general, the Sigma is a much better lens in terms of build quality, lens creep and usability.
The 18-250s are newer and better lenses than the 18-200s as is reflected in the prices. The Tamron 18-250 is a much better lense than it's smaller and cheaper brother.

05-24-2011, 02:11 AM   #24
Pentaxian
Class A's Avatar

Join Date: Aug 2008
Location: Wellington, New Zealand
Posts: 8,939
QuoteOriginally posted by Ash Quote
No third party lens manufacturers make weather-sealing or quick-shift focusing on their lenses for Pentax. These are the drawbacks.
Not true.

Many Sigma HSM lenses support manual focus override (aka "quick-shift" in Pentax parlance).

Also, Sigma has announced a number of weather resistant lenses a while ago. These might be available already, I didn't check.

As many already said: One has to compare lenses on a case by case basis. In general, Sigma is strong in offering high-quality primes (-> EX series, e.g., the 50/1.4, 30/1.4, 70/2.8, etc). Tamron offers two zooms which are often recommend on this forum: The 17-50/2.8 and the 28-75/2.8. Tamron and Sigma offer other great lenses (and some pedestrian ones too), I just highlighted a couple of very well-known ones.

I've got the Tamron 18-250 which is much better than many think who never tried it. It is definitely better than the 18-200 variants. Its only real problem is that it is not very bright ("fast"). But when you don't need the brightness -- Pentax in-body image stabilisation helps to alleviate this point -- it is almost impossible to beat it for versatility.
05-24-2011, 02:15 AM   #25
Pentaxian
Class A's Avatar

Join Date: Aug 2008
Location: Wellington, New Zealand
Posts: 8,939
QuoteOriginally posted by MK-x Quote
It seems that Sigma lenses have Image Stabilizer, which (I guess) makes the price higher. Too bad they don't have the same model without it.
Not all Sigma lenses have OS (optical stabilisation).

For those lenses who have OS, you'll often find older models on the used market which don't have OS but are often otherwise just as good.
05-24-2011, 06:20 AM   #26
Forum Member




Join Date: May 2011
Photos: Gallery
Posts: 93
Original Poster
QuoteOriginally posted by Class A Quote
I've got the Tamron 18-250 which is much better than many think who never tried it. It is definitely better than the 18-200 variants.
The difference is that visible?

I tried to look for Tamron 18-250, but couldn't find it. It seems that no one sells it.
Only Sigma 18-250.
05-24-2011, 08:32 AM   #27
Pentaxian
Marc Sabatella's Avatar

Join Date: Sep 2006
Location: Denver, CO
Photos: Gallery
Posts: 10,686
You might consider going to Photozone.de and comapring the sample images (as well as their tests). They don't test both on Pentax, but you can check the comparisons on Canon.

When I've done this, I can see the 18-250 is better, but perhaps not $300 better.
05-24-2011, 09:21 AM   #28
Site Supporter
K57XR's Avatar

Join Date: Feb 2011
Location: Colorado, USA
Posts: 813
QuoteOriginally posted by MK-x Quote
I tried to look for Tamron 18-250, but couldn't find it. It seems that no one sells it.
Pentax DA18-250/Tamron 18-250 have been discontinued and can only be found in the used market. I believe Tamron replaced it with the 18-270 but unfortunately, Tammy didn't make one for Pentax mount.
05-24-2011, 09:49 AM   #29
Pentaxian
Just1MoreDave's Avatar

Join Date: Feb 2007
Location: Aurora, CO
Photos: Gallery | Albums
Posts: 4,817
QuoteOriginally posted by Eliglass Quote
...However, one issue I am having with the Sigma is that the lens type does not show in any software have tried, including Lightroom 3.3 and EXIFTool. I use the Lens type for a lot of filtering in Lightroom. In addition, Lightroom has a lens proifile for the Sigma 18-250 for automatic lens corrections, but since the EXIF data is either missing or not decipherable, I cannot use this feature without manually setting the lens type.

Can anyone help with this issue?
Sigma does not pay Pentax a licensing fee to use the K-mount, they reverse-engineer lenses that they think will work. The lens works but Pentax is not going to tell Sigma how to provide unique lens identifiers. Sigma or Adobe might have a solution but Pentax won't.
05-24-2011, 10:11 AM   #30
Loyal Site Supporter
eddie1960's Avatar

Join Date: Aug 2010
Location: Toronto
Photos: Gallery | Albums
Posts: 12,168
QuoteOriginally posted by Ash Quote
No third party lens manufacturers make weather-sealing or quick-shift focusing on their lenses for Pentax. These are the drawbacks. However, the optical quality of most of their lenses are very good, each having their own reputation (which you should check for yourself on the forum's lens review database and on independent lens review sites).

Find what focal lengths you'd be after specifically (my thinking is a dual lens kit such as the Pentax 18-55, the best kit lens available, and something like a DA 55-300 if you can afford the combination) and then go out with your budget in mind for the lenses you're after.
Sigma announced 3 earlier this year 12-24 4.5-5.6, 120-300 2.81 150 macro 2.8 - (not cheap by any means) (he 120-300 won't be in pentax so far)

Sigma Corporation shares pricing, availability for three splash-proof lenses | sigmaphoto.com

They may not all be at market with the pentax mount yet but they are expected

“We’ve updated these popular lenses with our latest technology and design, while maintaining their compact size,” said Mark Amir-Hamzeh, president of Sigma Corporation of America. “The 120-300mm and the 150mm are now optically stabilized (OS), and all three lenses contain our new, splash-proof design, which will offer protection from water and dust. These are fantastic upgrades to already-great lenses.”
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!
18-55mm, brands, camera, da, lens, lenses, pentax, pentax help, photography, range, sigma, tamron
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Tamron 17-50mm, Tamron 28-75mm, Sigma 17-70mm, which lens for my trip to Greece? macky112 Pentax SLR Lens Discussion 15 11-20-2011 03:08 PM
For Sale - Sold: Sigma 24-60mm F2.8 (K mount) and Tamron Adaptall 24mm F2.5 with Tamron P/K ada pxpaulx Sold Items 4 08-27-2010 08:47 PM
Sigma 17-70mm - Differences between old and new one? jaieger Pentax SLR Lens Discussion 5 07-12-2010 06:13 PM
Tamron build differences usa or imported? metroeloise Pentax SLR Lens Discussion 14 10-25-2008 09:40 AM



All times are GMT -7. The time now is 09:16 AM. | See also: NikonForums.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