Fast Zoom for Indoors

**pres589** · 11-21-2018, 02:10 PM - **1 Like**

I like 28mm lenses on crop (and full frame) for the field of view they offer. Having an f1.8 lens to gather light indoors is not to be ignored. This lens is pretty good from wide open and I've taken some portraits casually with it. They have a nice 3d pop to them. Crop if you need to of course.

reh321, a used Sigma 17-70 should be pretty cheap these days, I guess, but it's hard to argue with getting a brand new Tamron 17-50 f2.8 for $300 USD vs. a variable aperture lens that lets in less light. Sure, just screw the ISO a bit tighter to compensate, but isn't it nice when you don't have to? Also having that constant f2.8 makes for more artistic opportunities inre: depth of field.

**RKKS08** · 11-21-2018, 03:02 PM - **1 Like**

I got a used Tamron 2.8/18-50 in very good condition earlier this year for €121 (on eBay).
They are now frequently in the € 100 range. This lens is very good at all focal lengths, even at F2.8.

With most affordable zoom lenses starting at 16-18mm, you pay a price for going further than 55mm on the long end. Either by less corner resolution at the long end, or more distortion at the short end, or variable aperture,.or several of these. But if you don't pixel peep, don't print very large, and don't shoot architecture, you may rarely notice it. Otherwise all the 18-2xx soup zooms would not sell at all.

reh321 · 11-21-2018, 06:53 PM - **1 Like**

Originally posted by RKKS08

With most affordable zoom lenses starting at 16-18mm, you pay a price for going further than 55mm on the long end. Either by less corner resolution at the long end, or more distortion at the short end, or variable aperture,.or several of these. But if you don't pixel peep, don't print very large, and don't shoot architecture, you may rarely notice it. Otherwise all the 18-2xx soup zooms would not sell at all.

My 18-135mm is a fine lens; I wouldn't use a 18-270.
I'm not interested in corner-to-corner needle-sharpness and I want to show my subject in context.
I want the best part of the photo to be towards the center, because 'center ring' is where I put the main subject.
I don't print at all, and I would prefer that people not pixel-peek.
The story is told by the photo as a whole, and that is what I want people to look at.

**RKKS08** · 11-22-2018, 07:56 AM - **1 Like**

@reh321
If I have no idea what I may shoot, and don't want to carry additional lenses, I use the Sgma 3.8-5.6/18-125 DC.

From what I saw (and read), overall image quality and also weaknesses are very comparable to the DA 18-135. But of course there is no WR and quickshift. It is now some time out of production, and eBay auction prices are often < €100.

I did not suggest it to the OP, as the Tamron 2.8/17-50 is so much better, and (used) only slightly more expensive. And if you occasional use it also for landscape or archtecture, you'll appreciate the better corner resolution at all apertures.

**mikesbike** · 11-22-2018, 07:21 PM - **1 Like**

Unfortunately, the KP body is beyond the budget given. However, the rationale for the KP is valid, since it will deliver performance for indoor use at a higher ISO that is more than one stop superior to that of the K-3. So while one lens can provide good results at f/4 or 4.5 at a certain FL, with the KP the resultant available shutter speed, while maintaining fine noise and image-detail performance, would be at least equivalent to an f/2.8 lens on the K-3.

But even with the KP, there is still yet more advantage in having the f/2.8 availability with good performance, since shutter speed for hand-held, or for subjects with activity, can be yet higher. Eventually, a KP might be in your future.

For indoor use, without flash, a good professional-style zoom lens of f/2.8 constant aperture is hard to beat. I would recommend the Sigma EX 17-50mm f/2.8 DC HSM. I have this lens. There is a good review of it, which includes a visual test, by Imaging Resource. If you google the lens including the word review, the Imaging Resource listing should come up. The still life test photo is the best to go by. Just click on the image and you will be given a selection of f/2.8 or f/8 at each of 3 FLs. You then will get a huge blowup. For center performance, just click on the inner edge of the basket. From there you can pan around to bottle tops, and labels with their own images, which are a good reference, and lettering, such as the lettering on the Samuel Smith Pure Brewed label, and farther towards the edge with the circular numbered scale.

Remember, this is a huge blowup. But this visual test does provide a good reference for real-world performance.

I do not agree with statements regarding the Tamron 17-50mm. The Sigma lens test definitely looks better to me, and has a much better build quality, as well as quiet, accurate AF performance. I have seen multiple service issues reported regarding the Tamron lens.

My Sigma 17-50mm f/2.8 lens does well even when paired with my excellent Pentax DA* 50-135mm f/2.8 which says a lot for its image quality. As far as a lens going to 70mm and F/4, it would not take much cropping of an f/2.8 image at 50mm to get the same framing, and you'd still have the benefit of the faster shutter speed.

I got mine earlier this year from B&H at a good price.

**RKKS08** · 11-23-2018, 10:23 AM - **1 Like**

Originally posted by mikesbike

I do not agree with statements regarding the Tamron 17-50mm. The Sigma lens test definitely looks better to me, and has a much better build quality, as well as quiet, accurate AF performance. I have seen multiple service issues reported regarding the Tamron lens.

From the comprehensive DA* 16-50mm vs. Sigma and Tamron 17-50mm F2.8 comparison in our (Pentaxforums staff) review section:

Quote:

"Going into this review, we knew that all three leses were highly regarded by owners. We also knew that they offered different levels of features and construction quality. In those respects, there were no surprises. The Pentax and Sigma lenses are far more fully-featured than the Tamron. They're also larger and heavier, by quite a large degree.

What we weren't so sure about was their relative optical performance. Given their prices, one could be forgiven for assuming that the Pentax and Sigma offerings would beat the pants off the Tamron. However, particularly for the Pentax, this simply wasn't the case. Though the Tamron ranks second overall in the final scoring, it earned that competitiveness almost solely on the merits of the image quality it can produce. While we'd hesitate to say it's a definitively better lens than the Sigma optically, it does at times exceed the Sigma in sharpness, and roundly bests it flare resistance while edging slightly ahead in other categories as well."

DA* 16-50mm vs. Sigma and Tamron 17-50mm F2.8 Comparison Review - Introduction | PentaxForums.com Reviews

I cannot compare myself, as I do not own the Sigma. What exactly are the service problems with the Tamron?
I can't judge, but - specially on this forum - I read more often about such problems concerning Sigma lenses (in general, not about the 17-50).

normhead · 11-23-2018, 11:14 AM - **1 Like**

There's also the Pentax 17-70.... $376 B&H dollars.
Pentax SMCP-DA 17-70mm f/4 AL (IF) SDM Autofocus Lens 21740 B&H
SMC Pentax-DA 17-70mm F4 AL [IF] SDM Reviews - DA Zoom Lenses - Pentax Lens Reviews & Lens Database
Pentax SMC DA 17-70mm f/4 AL [IF] SDM - Review / Test Report - Analysis

And the Sigma 17-70 $449
Sigma 17-70mm F2.8-4 DC Macro HSM (Contemporary) Lens Reviews - Sigma Lenses - Pentax Lens Review Database
Sigma 17-70 For Pentax | B&H Photo Video
Sigma AF 17-70mm f/2.8-4.5 DC (Pentax K) - Review / Test Report - Analysis

They seem to be rated pretty close to each other, with Sigma having ƒ2.8 at some focal lengths, but the Pentax having constant f4 for easier flash use.

There are a lot of similarities, the SIgma is better at 70mm, not much difference anywhere else with both having strong points at different focal lengths but pretty much a saw off. The Sigma at 2.8 is certainly nothing worth writing home about. The DA 17-70 has much worse control of CA, but in many cases slightly higher resolution. The CA may of may not raise it's ugly head, the resolution doesn't change.

So for me, it's whether you want to max out your limit or leave yourself 75 bucks.

I'd look at older glass if you can find it, but, I can never find it when I want it, so I have no idea how practical that would be. And I always prefer shiny new as opposed to used for $100 less. People always seem to think the warranty isn't worth anything when they sell lenses. My F 70-210 is a purple fringe monster, it makes me leery of film lenses in general. For a really good deal, i certainly give older glass try, IMHE you have to be prepared to throw money away with cheaper glass.

Another choice could be the TAMRON DI 28-75MM D F2.8 XR PENTAX. I can't find a B&H price but Amazon has it for $347
TAMRON DI 28-75MM D F2.8 XR PENTAX
amazon.com : Tamron AF 28-75mm f/2.8 SP XR Di LD Aspherical (IF) for Pentax (Model A09P) - International Version (No Warranty) : Camera Lenses : Camera & Photo?tag=pentaxforums-20&
Tamron AF 28-75mm f/2.8 SP XR Di LD Aspherical (IF) - Review / Test Report - Analysis
https://www.pentaxforums.com/userreviews/tamron-28-75mm-f2-8-af-xr-di-ld-macro-sp.html

Will be rated excellent for centre sharpness better than the other 2, but worse for edge sharpness. Control of CA is in between the Pentax and the Sigma. You give up 17-28mm in focal length but you get constant ƒ2.8.

And then there are lenses like the 17-50s and 16 50, although personally I find those lenses too limited in zoom range for the use you describe. In this situations I often use 70mm for close ups and head shots.

That's three new choices. Unless you can get a spectacular price on something similar used, i'd go with one of those.

Anyway, lots to think about.

Last edited by normhead; 11-23-2018 at 11:28 AM.

angerdan · 11-23-2018, 01:18 PM - **1 Like**

I really wonder why the fastest indor zoom lens for Pentax isn't named:
Sigma 18-35mm F1.8 DC HSM (Art) Lens Reviews - Sigma Lenses - Pentax Lens Review Database
Sigma 18-35mm F1.8 DC HSM "Art" Review - Introduction | PentaxForums.com Reviews

normhead · 11-23-2018, 01:36 PM - **2 Likes**

Originally posted by angerdan

I really wonder why the fastest indor zoom lens for Pentax isn't named:
Sigma 18-35mm F1.8 DC HSM (Art) Lens Reviews - Sigma Lenses - Pentax Lens Review Database
Sigma 18-35mm F1.8 DC HSM "Art" Review - Introduction | PentaxForums.com Reviews

Because it's twice the price the OP asked for? Could be one reason.

Because it has focus issues.?

Because I'm not sure what 18-35 is for, I barely ever use mine (An FAJ 18-35) It's just not a terribly useful focal length.)
Because it's not long enough, even shorter than the various 17-50 and 16-50?

It generally not a good idea to carry a lens that big unless it does everything you want that day. It's hard to imagine a circumstance where all your shooting is between ultra wild and wide.

I can probably think of a few more, but that's no doubt a start.

**TwoUptons** · 11-23-2018, 03:00 PM - **1 Like**

I love my DA* 16-50 on APS.
The only flaw of significance is that when shooting indoors with a flash, especially with the hood, the lens shades a built-in flash at wide angles.
Otherwise it is a superb child-chasing optic

Though, to be fair, that’s going to be characteristic of a lot of lenses larger and/or wider than the 18-55...

-Eric

normhead · 11-23-2018, 03:15 PM - **1 Like**

Originally posted by RKKS08

@reh321
If I have no idea what I may shoot, and don't want to carry additional lenses, I use the Sgma 3.8-5.6/18-125 DC.

From what I saw (and read), overall image quality and also weaknesses are very comparable to the DA 18-135. But of course there is no WR and quickshift. It is now some time out of production, and eBay auction prices are often < €100.

I did not suggest it to the OP, as the Tamron 2.8/17-50 is so much better, and (used) only slightly more expensive. And if you occasional use it also for landscape or archtecture, you'll appreciate the better corner resolution at all apertures.

On the test charts that Sigma 18-125 looks like a heck of a lens. Wonder why it went out of fashion? Even chormaic aberrations and distortionary well controlled. Rare in a lens of this type.

**mikesbike** · 11-23-2018, 03:17 PM - **1 Like**

One can look at the same comparative image between 2 lenses and judge for one's self. The Tamron 17-50mm f/2.8 came out very well via machine based lab equipment, however. I also came across a test report of the Tamron 50mm f/2.8 lens having a lot of field curvature, (maybe Optical Limits?) while the Sigma's was exceptionally low.

I cannot recall the exact defect, but I did see some postings not long ago regarding turn-around time for repair of some structural failure of the Tamron lens that was common to several posters in the thread.

As for as a 70mm f/4 lens, for indoor lighting with no flash, you get half the shutter speed of f/2.8 under the same settings and conditions. I cannot see going for less aperture than f/2.8 for such use as to a fast zoom lens for indoor lighting with no flash, except with a KP, K-70, or a K-1 could one possibly get away with f/4. But even then it would be better to have at least f/2.8 available. It only takes a very light crop of a 50mm image to equal the framing of a 70mm image, and you'd still have the shutter speed advantage. 50mm on its own with APS-C provides very good perspective and a good shooting distance for portrait use. With the Pentax 1.53x crop factor, its is similar to 76.5mm on 35mm film or a FF DSLR.

erluko · 12-21-2018, 05:26 AM - **1 Like**

I'll second the recommendation for the Sigma 17-50/2.8. It can be found used for under $400 regularly on eBay. There's one listed for $240 shipped(!) right now.

There are also the 28-70/2.8 lenses from several manufacturers in the $200 range, but you might want that extra wide angle space indoors.

Going with a constant aperture lens means you don't have to recalculate exposure as you zoom if you're in M mode and you don't have to worry about noise-inducing ISO jumps while zooming in TAv mode.

**jawats** · 12-22-2018, 08:11 AM

Originally posted by erluko

I'll second the recommendation for the Sigma 17-50/2.8. It can be found used for under $400 regularly on eBay. There's one listed for $240 shipped(!) right now.

There are also the 28-70/2.8 lenses from several manufacturers in the $200 range, but you might want that extra wide angle space indoors.

Going with a constant aperture lens means you don't have to recalculate exposure as you zoom if you're in M mode and you don't have to worry about noise-inducing ISO jumps while zooming in TAv mode.

I ended up paying about $30 for a used Tamron SP 28-75mm f/2.8 - here: Tamron 28-75mm F2.8 AF XR Di LD Macro SP Lens Reviews - Tamron Lenses - Pentax Lens Review Database

Seemed like a good deal. Advertised as is, but really, haven't seen the issues with it yet (claimed too soft at wide open, which apparently is a "feature" of the lens). At any rate, I'll be testing it on cats and martial arts, and will let you know what comes of it.

**mikesbike** · 12-22-2018, 05:19 PM - **1 Like**

Well, if it is in decent condition, you can't beat that deal at $30!! This is a highly-regarded lens. It is designed for 35mm film or a FF DSLR. So, no wide angle on APS-C DSLR bodies, which is ok if one has no interest in wider than 28mm. Few if any lenses are at their best wide open, so just getting good results here is good enough.

11-22-2018, 07:21 PM - 1 Like	#20
mikesbike Site Supporter Join Date: Dec 2016 Location: Southeastern Michigan Posts: 4,558	Unfortunately, the KP body is beyond the budget given. However, the rationale for the KP is valid, since it will deliver performance for indoor use at a higher ISO that is more than one stop superior to that of the K-3. So while one lens can provide good results at f/4 or 4.5 at a certain FL, with the KP the resultant available shutter speed, while maintaining fine noise and image-detail performance, would be at least equivalent to an f/2.8 lens on the K-3. But even with the KP, there is still yet more advantage in having the f/2.8 availability with good performance, since shutter speed for hand-held, or for subjects with activity, can be yet higher. Eventually, a KP might be in your future. For indoor use, without flash, a good professional-style zoom lens of f/2.8 constant aperture is hard to beat. I would recommend the Sigma EX 17-50mm f/2.8 DC HSM. I have this lens. There is a good review of it, which includes a visual test, by Imaging Resource. If you google the lens including the word review, the Imaging Resource listing should come up. The still life test photo is the best to go by. Just click on the image and you will be given a selection of f/2.8 or f/8 at each of 3 FLs. You then will get a huge blowup. For center performance, just click on the inner edge of the basket. From there you can pan around to bottle tops, and labels with their own images, which are a good reference, and lettering, such as the lettering on the Samuel Smith Pure Brewed label, and farther towards the edge with the circular numbered scale. Remember, this is a huge blowup. But this visual test does provide a good reference for real-world performance. I do not agree with statements regarding the Tamron 17-50mm. The Sigma lens test definitely looks better to me, and has a much better build quality, as well as quiet, accurate AF performance. I have seen multiple service issues reported regarding the Tamron lens. My Sigma 17-50mm f/2.8 lens does well even when paired with my excellent Pentax DA* 50-135mm f/2.8 which says a lot for its image quality. As far as a lens going to 70mm and F/4, it would not take much cropping of an f/2.8 image at 50mm to get the same framing, and you'd still have the benefit of the faster shutter speed. I got mine earlier this year from B&H at a good price. Last edited by mikesbike; 11-22-2018 at 07:44 PM.

11-23-2018, 03:17 PM - 1 Like	#27
mikesbike Site Supporter Join Date: Dec 2016 Location: Southeastern Michigan Posts: 4,558	One can look at the same comparative image between 2 lenses and judge for one's self. The Tamron 17-50mm f/2.8 came out very well via machine based lab equipment, however. I also came across a test report of the Tamron 50mm f/2.8 lens having a lot of field curvature, (maybe Optical Limits?) while the Sigma's was exceptionally low. I cannot recall the exact defect, but I did see some postings not long ago regarding turn-around time for repair of some structural failure of the Tamron lens that was common to several posters in the thread. As for as a 70mm f/4 lens, for indoor lighting with no flash, you get half the shutter speed of f/2.8 under the same settings and conditions. I cannot see going for less aperture than f/2.8 for such use as to a fast zoom lens for indoor lighting with no flash, except with a KP, K-70, or a K-1 could one possibly get away with f/4. But even then it would be better to have at least f/2.8 available. It only takes a very light crop of a 50mm image to equal the framing of a 70mm image, and you'd still have the shutter speed advantage. 50mm on its own with APS-C provides very good perspective and a good shooting distance for portrait use. With the Pentax 1.53x crop factor, its is similar to 76.5mm on 35mm film or a FF DSLR. Last edited by mikesbike; 11-23-2018 at 04:04 PM.

12-21-2018, 05:26 AM - 1 Like	#28
erluko New Member Join Date: Sep 2017 Posts: 14	Sigma 100% I'll second the recommendation for the Sigma 17-50/2.8. It can be found used for under $400 regularly on eBay. There's one listed for $240 shipped(!) right now. There are also the 28-70/2.8 lenses from several manufacturers in the $200 range, but you might want that extra wide angle space indoors. Going with a constant aperture lens means you don't have to recalculate exposure as you zoom if you're in M mode and you don't have to worry about noise-inducing ISO jumps while zooming in TAv mode.

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11-21-2018, 02:10 PM - 1 Like	#16
pres589 Site Supporter Join Date: Jan 2014 Location: Wichita, KS Photos: Albums Posts: 4,533	I like 28mm lenses on crop (and full frame) for the field of view they offer. Having an f1.8 lens to gather light indoors is not to be ignored. This lens is pretty good from wide open and I've taken some portraits casually with it. They have a nice 3d pop to them. Crop if you need to of course. reh321, a used Sigma 17-70 should be pretty cheap these days, I guess, but it's hard to argue with getting a brand new Tamron 17-50 f2.8 for $300 USD vs. a variable aperture lens that lets in less light. Sure, just screw the ISO a bit tighter to compensate, but isn't it nice when you don't have to? Also having that constant f2.8 makes for more artistic opportunities inre: depth of field.

11-21-2018, 03:02 PM - 1 Like	#17
RKKS08 Site Supporter Join Date: Mar 2010 Location: Frankfurt am Main Posts: 1,241	I got a used Tamron 2.8/18-50 in very good condition earlier this year for €121 (on eBay). They are now frequently in the € 100 range. This lens is very good at all focal lengths, even at F2.8. With most affordable zoom lenses starting at 16-18mm, you pay a price for going further than 55mm on the long end. Either by less corner resolution at the long end, or more distortion at the short end, or variable aperture,.or several of these. But if you don't pixel peep, don't print very large, and don't shoot architecture, you may rarely notice it. Otherwise all the 18-2xx soup zooms would not sell at all.

11-21-2018, 06:53 PM - 1 Like	#18
reh321 Pentaxian Join Date: Nov 2014 Location: South Bend, IN, USA Photos: Gallery \| Albums Posts: 23,181	Originally posted by RKKS08 With most affordable zoom lenses starting at 16-18mm, you pay a price for going further than 55mm on the long end. Either by less corner resolution at the long end, or more distortion at the short end, or variable aperture,.or several of these. But if you don't pixel peep, don't print very large, and don't shoot architecture, you may rarely notice it. Otherwise all the 18-2xx soup zooms would not sell at all. My 18-135mm is a fine lens; I wouldn't use a 18-270. I'm not interested in corner-to-corner needle-sharpness and I want to show my subject in context. I want the best part of the photo to be towards the center, because 'center ring' is where I put the main subject. I don't print at all, and I would prefer that people not pixel-peek. The story is told by the photo as a whole, and that is what I want people to look at.

11-22-2018, 07:56 AM - 1 Like	#19
RKKS08 Site Supporter Join Date: Mar 2010 Location: Frankfurt am Main Posts: 1,241	@reh321 If I have no idea what I may shoot, and don't want to carry additional lenses, I use the Sgma 3.8-5.6/18-125 DC. From what I saw (and read), overall image quality and also weaknesses are very comparable to the DA 18-135. But of course there is no WR and quickshift. It is now some time out of production, and eBay auction prices are often < €100. I did not suggest it to the OP, as the Tamron 2.8/17-50 is so much better, and (used) only slightly more expensive. And if you occasional use it also for landscape or archtecture, you'll appreciate the better corner resolution at all apertures.

11-23-2018, 10:23 AM - 1 Like	#21
RKKS08 Site Supporter Join Date: Mar 2010 Location: Frankfurt am Main Posts: 1,241	Originally posted by mikesbike I do not agree with statements regarding the Tamron 17-50mm. The Sigma lens test definitely looks better to me, and has a much better build quality, as well as quiet, accurate AF performance. I have seen multiple service issues reported regarding the Tamron lens. From the comprehensive DA* 16-50mm vs. Sigma and Tamron 17-50mm F2.8 comparison in our (Pentaxforums staff) review section: Quote: "Going into this review, we knew that all three leses were highly regarded by owners. We also knew that they offered different levels of features and construction quality. In those respects, there were no surprises. The Pentax and Sigma lenses are far more fully-featured than the Tamron. They're also larger and heavier, by quite a large degree. What we weren't so sure about was their relative optical performance. Given their prices, one could be forgiven for assuming that the Pentax and Sigma offerings would beat the pants off the Tamron. However, particularly for the Pentax, this simply wasn't the case. Though the Tamron ranks second overall in the final scoring, it earned that competitiveness almost solely on the merits of the image quality it can produce. While we'd hesitate to say it's a definitively better lens than the Sigma optically, it does at times exceed the Sigma in sharpness, and roundly bests it flare resistance while edging slightly ahead in other categories as well." DA* 16-50mm vs. Sigma and Tamron 17-50mm F2.8 Comparison Review - Introduction \| PentaxForums.com Reviews I cannot compare myself, as I do not own the Sigma. What exactly are the service problems with the Tamron? I can't judge, but - specially on this forum - I read more often about such problems concerning Sigma lenses (in general, not about the 17-50).

11-23-2018, 11:14 AM - 1 Like	#22
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,451	There's also the Pentax 17-70.... $376 B&H dollars. Pentax SMCP-DA 17-70mm f/4 AL (IF) SDM Autofocus Lens 21740 B&H SMC Pentax-DA 17-70mm F4 AL [IF] SDM Reviews - DA Zoom Lenses - Pentax Lens Reviews & Lens Database Pentax SMC DA 17-70mm f/4 AL [IF] SDM - Review / Test Report - Analysis And the Sigma 17-70 $449 Sigma 17-70mm F2.8-4 DC Macro HSM (Contemporary) Lens Reviews - Sigma Lenses - Pentax Lens Review Database Sigma 17-70 For Pentax \| B&H Photo Video Sigma AF 17-70mm f/2.8-4.5 DC (Pentax K) - Review / Test Report - Analysis They seem to be rated pretty close to each other, with Sigma having ƒ2.8 at some focal lengths, but the Pentax having constant f4 for easier flash use. There are a lot of similarities, the SIgma is better at 70mm, not much difference anywhere else with both having strong points at different focal lengths but pretty much a saw off. The Sigma at 2.8 is certainly nothing worth writing home about. The DA 17-70 has much worse control of CA, but in many cases slightly higher resolution. The CA may of may not raise it's ugly head, the resolution doesn't change. So for me, it's whether you want to max out your limit or leave yourself 75 bucks. I'd look at older glass if you can find it, but, I can never find it when I want it, so I have no idea how practical that would be. And I always prefer shiny new as opposed to used for $100 less. People always seem to think the warranty isn't worth anything when they sell lenses. My F 70-210 is a purple fringe monster, it makes me leery of film lenses in general. For a really good deal, i certainly give older glass try, IMHE you have to be prepared to throw money away with cheaper glass. Another choice could be the TAMRON DI 28-75MM D F2.8 XR PENTAX. I can't find a B&H price but Amazon has it for $347 TAMRON DI 28-75MM D F2.8 XR PENTAX amazon.com : Tamron AF 28-75mm f/2.8 SP XR Di LD Aspherical (IF) for Pentax (Model A09P) - International Version (No Warranty) : Camera Lenses : Camera & Photo?tag=pentaxforums-20& Tamron AF 28-75mm f/2.8 SP XR Di LD Aspherical (IF) - Review / Test Report - Analysis https://www.pentaxforums.com/userreviews/tamron-28-75mm-f2-8-af-xr-di-ld-macro-sp.html Will be rated excellent for centre sharpness better than the other 2, but worse for edge sharpness. Control of CA is in between the Pentax and the Sigma. You give up 17-28mm in focal length but you get constant ƒ2.8. And then there are lenses like the 17-50s and 16 50, although personally I find those lenses too limited in zoom range for the use you describe. In this situations I often use 70mm for close ups and head shots. That's three new choices. Unless you can get a spectacular price on something similar used, i'd go with one of those. Anyway, lots to think about. Last edited by normhead; 11-23-2018 at 11:28 AM.

11-23-2018, 01:18 PM - 1 Like	#23
angerdan Pentaxian Join Date: Feb 2015 Photos: Gallery \| Albums Posts: 2,642	I really wonder why the fastest indor zoom lens for Pentax isn't named: Sigma 18-35mm F1.8 DC HSM (Art) Lens Reviews - Sigma Lenses - Pentax Lens Review Database Sigma 18-35mm F1.8 DC HSM "Art" Review - Introduction \| PentaxForums.com Reviews

11-23-2018, 01:36 PM - 2 Likes	#24
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,451	Originally posted by angerdan I really wonder why the fastest indor zoom lens for Pentax isn't named: Sigma 18-35mm F1.8 DC HSM (Art) Lens Reviews - Sigma Lenses - Pentax Lens Review Database Sigma 18-35mm F1.8 DC HSM "Art" Review - Introduction \| PentaxForums.com Reviews Because it's twice the price the OP asked for? Could be one reason. Because it has focus issues.? Because I'm not sure what 18-35 is for, I barely ever use mine (An FAJ 18-35) It's just not a terribly useful focal length.) Because it's not long enough, even shorter than the various 17-50 and 16-50? It generally not a good idea to carry a lens that big unless it does everything you want that day. It's hard to imagine a circumstance where all your shooting is between ultra wild and wide. I can probably think of a few more, but that's no doubt a start.

11-23-2018, 03:00 PM - 1 Like	#25
TwoUptons Loyal Site Supporter Join Date: Nov 2015 Photos: Albums Posts: 4,223	I love my DA* 16-50 on APS. The only flaw of significance is that when shooting indoors with a flash, especially with the hood, the lens shades a built-in flash at wide angles. Otherwise it is a superb child-chasing optic Though, to be fair, that’s going to be characteristic of a lot of lenses larger and/or wider than the 18-55... -Eric

11-23-2018, 03:15 PM - 1 Like	#26
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,451	Originally posted by RKKS08 @reh321 If I have no idea what I may shoot, and don't want to carry additional lenses, I use the Sgma 3.8-5.6/18-125 DC. From what I saw (and read), overall image quality and also weaknesses are very comparable to the DA 18-135. But of course there is no WR and quickshift. It is now some time out of production, and eBay auction prices are often < €100. I did not suggest it to the OP, as the Tamron 2.8/17-50 is so much better, and (used) only slightly more expensive. And if you occasional use it also for landscape or archtecture, you'll appreciate the better corner resolution at all apertures. On the test charts that Sigma 18-125 looks like a heck of a lens. Wonder why it went out of fashion? Even chormaic aberrations and distortionary well controlled. Rare in a lens of this type.

12-22-2018, 08:11 AM	#29
jawats Site Supporter Join Date: Nov 2017 Photos: Gallery \| Albums Posts: 756 Original Poster	Originally posted by erluko I'll second the recommendation for the Sigma 17-50/2.8. It can be found used for under $400 regularly on eBay. There's one listed for $240 shipped(!) right now. There are also the 28-70/2.8 lenses from several manufacturers in the $200 range, but you might want that extra wide angle space indoors. Going with a constant aperture lens means you don't have to recalculate exposure as you zoom if you're in M mode and you don't have to worry about noise-inducing ISO jumps while zooming in TAv mode. I ended up paying about $30 for a used Tamron SP 28-75mm f/2.8 - here: Tamron 28-75mm F2.8 AF XR Di LD Macro SP Lens Reviews - Tamron Lenses - Pentax Lens Review Database Seemed like a good deal. Advertised as is, but really, haven't seen the issues with it yet (claimed too soft at wide open, which apparently is a "feature" of the lens). At any rate, I'll be testing it on cats and martial arts, and will let you know what comes of it.

12-22-2018, 05:19 PM - 1 Like	#30
mikesbike Site Supporter Join Date: Dec 2016 Location: Southeastern Michigan Posts: 4,558	Well, if it is in decent condition, you can't beat that deal at $30!! This is a highly-regarded lens. It is designed for 35mm film or a FF DSLR. So, no wide angle on APS-C DSLR bodies, which is ok if one has no interest in wider than 28mm. Few if any lenses are at their best wide open, so just getting good results here is good enough.