Good lens for Kids + Travel

edice · 07-09-2010, 09:32 AM

Hi,

I have a K100D, the 18-50mm kit lens and a fast Pentax 50mm 1.4 lens.

Now I'm going on a 2 week Italian holiday and am looking for a lens that will work well with landscapes, churches, streets, people, me in front of interesting statues, AND also be useful once I get home to my 2-year-old kid.

I find that I'm unable to take any sort of landscape shot, so wide would be good. I don't really feel the need to take a lot of detail-shots, so a strong zoom isn't a big priority although it would be nice from time to time.

As I already have an 18-50mm lens, I'm not excited about getting another lens in the same field... although I am well aware of the limitations of my kit lens in indoor situations (ie near-hopeless without flash). So if its going to cover the same focal length, its going to need to be faster.

Budget is enough for 1 decent lens of "reasonable price", so less than or around the US$500 rather than US$1000. Cheap is good, but I want a lens I will use and enjoy, not something to regret. I'm not a pro, so a really good lens might be wasted on me.

I've crawled through this forum and a few others, and am thinking along these lines:

DA 21mm f3.2 limited
This seems to be touted as the "unobtrusive tourist lens", with good field of view and good speed, and excellent weight.
But, won't my 18-50mm do the same job "acceptably" ? At 18mm the kit lens is f3.5...

DA 12-24 f4
Nice and wide, and apparently as good as the 21mm. Pricey, and is it fast enough for indoor shots at Christmas?

Pentax 18-250mm (3.5-6.5)
Great all-round lens, but its as slow as my current kit lens, so no benefit at the wide end.

Pentax/Bower 14mm F2.8
A bit too wide? I see a Bower on B+H.

Tamron 17-50 f2.8
I read mixed reviews about the Tamrons, but most of the negatives seem to be about the bokeh. If I want that, I can use my 50mm f1.4... so would these be suitable for me?

Tamron 10-24 f3.5-4.5
Cheaper than the Pentax, AND wider. Why not this lens?

other lenses?

i'm swimming in options but I'm not sure what would be appropriate... please help!

thanks
Paul

Adam · 07-09-2010, 09:54 AM

What about this lens: PentaxForums.com Third-Party Lens Review Database - Sigma 24-70mm F2.8 EX DG MACRO (AF Lens) Lens Reviews

It's not as wide as your kit, but it's covers the entire 24-55mm range, and then some, and is 0.5 to 2 stops faster. It's also a full-frame lens and has macro capabilities as a bonus.

I've used the Pentax 28-70mm (which is very comparable to the Sigma) as a walkaround, and have been quite satisfied! At 70mm, the lens was also very good for portraits (which I'm sure you take a lot of!).

Ira · 07-09-2010, 09:59 AM

I second Adam's range above, so also look at the 28-75 Tamron.

Landscapes are one thing, so to expect a 14 to work for kids is a little unrealistic. But that being said, I never understood when people say they want a lens to shoot kids, because as far as I know, their reflections will indeed pass through the glass of a 14.

bdery · 07-09-2010, 10:22 AM

DA 21mm f3.2 limited
The 21 is way better than the kit lens. I own it and it complements my F50 f1,7 perfectly as a low light task force. It's small and light enough to be handheld for indoors shots without flash. It would be a good choice.

DA 12-24 f4
F4 isn't fast enough for indoor shots without flash, I'd say.

Pentax 18-250mm (3.5-6.5)
Would be a horrible choice for inside of buildings in Italy. I've been there (with a P&S at the time) and I yearned for a faster lens.

Pentax/Bower 14mm F2.8
Very wide. Your call.

Tamron 17-50 f2.8
Supposed to be great.

Tamron 10-24 f3.5-4.5
No opinon.

The Tamron 28-75 would be a good choice too. It really boils down to your shooting style. I personally use the Sigma 17-70 for everyday shots, and carry the 21 and 50 for low light. That's how I work. Your way of working must be different, and no one knows you better than you

edice · 07-10-2010, 12:04 AM

Thanks for the replies, this is really helping me.

Side note:
I was just comparing my P&S Panasonic Lumix DMC FX38 (4-22mm, f/2.8-5.9) and noticed that its as wide as my kit lens at 18mm, but can zoom in about twice as far. How does that work? Can the lens length only be compared with cameras of the same sensor size?

Back on topic,
I'm thinking about the photos that I'd love to take and can't, and I'd have to say those are low light, and/or wide-angle such as family gatherings and landscapes. My previous "wife in front of nice church/mountain/city" photos are often just of a tiny part of the city - the finished photo doesn't give you a sense of scale.

is the extra 1 mm going to make 17mm much wider than 18mm? It doesn't sound like much!

So, I like the idea of the Tamron 17-50 f/2.8, I agree that it would service most of my needs, and I don't see any other lens that give that sort of range and speed, especially at the wide end of the scale.

I looked through the photos found here:
17-50mm: Tamron SP AF 17-50mm f/2.8 XR Di-II LD Asp IF Lens Sample Photos and Specifications
28-75mm: Tamron SP AF 28-75mm f/2.8 XR Di LD (IF) Lens Sample Photos and Specifications

And I've only seen a couple of churches - in the 17-50 section. The photos I could see myself taking in the 28-75mm section were all 35mm or 50mm, I didn't see many photos using the extra zoom.
But thats hard to tell, is there somewhere I can use to look at (eg) "all photos taken with focal length 70-75mm" ?

So far the 17-50mm looks like the one!

thanks,
Paul

bdery · 07-10-2010, 07:57 AM

17 vs 18 will be much more noticeable than, say, 200 vs 201. So yeah, you'll notice it.

Regarding your "side note" question, there's about an infinite number of ways to design a lens. If you make a zoom lens starting at 18 mm, you can have it rach 25, 100, 250 mm if you want.

OF COURSE there are always compromises when designing lenses. The longer the reach, the more compromises you have to make. But the focal length range itself is not limited.

pb_red · 07-10-2010, 11:03 AM

edice, welcome to the forum!

first, if you have the pentax kit lens then it's an 18-55mm, not 18-50.

in any case, i've been thinking about what i want in a travel lens for a while and it's definitely a zoom lens since as much as i like primes they are just not versatile enough when traveling with others who don't want to stop and wait for you to change lenses all the time.

also, while the 18-55mm is actually a pretty darn good lens it's just not as wide as i'd like or as long as it'd like sometimes. so the main lenses i considered were the 18-200's, 18-250's, and 17-70's.

i went with a 17-70 because i prefer to shoot wide angle so that extra 1mm over stock makes a difference and the extra 15mm on the long end is nice as well. i just could not imagine taking many photos in the 70-250 range so i ignored the superzooms.
i went with the pentax lens over sigma because i like the constant f4 aperture.

i hope you find this info useful and good luck with whatever you chose.

Biro · 07-10-2010, 12:02 PM

Originally posted by edice

Thanks for the replies, this is really helping me.

Side note:
I was just comparing my P&S Panasonic Lumix DMC FX38 (4-22mm, f/2.8-5.9) and noticed that its as wide as my kit lens at 18mm, but can zoom in about twice as far. How does that work? Can the lens length only be compared with cameras of the same sensor size?

That's right... the only way that Panasonic can enjoy a long focal zoom range like that is its tiny sensor. And I'm sure that camera will take fine images in good light. It's in low light and at high ISOs that the small sensor reveals its limitations.

Originally posted by edice

Back on topic,
I'm thinking about the photos that I'd love to take and can't, and I'd have to say those are low light, and/or wide-angle such as family gatherings and landscapes. My previous "wife in front of nice church/mountain/city" photos are often just of a tiny part of the city - the finished photo doesn't give you a sense of scale.

is the extra 1 mm going to make 17mm much wider than 18mm? It doesn't sound like much!

While an extra few mm (or even 50mm) on the long end isn't as noticeable as you might think, it's quite a different situation at the wide end. 1mm may be pushing it... but 2, 3 or 4mm is quite noticeable.

Originally posted by edice

So, I like the idea of the Tamron 17-50 f/2.8, I agree that it would service most of my needs, and I don't see any other lens that give that sort of range and speed, especially at the wide end of the scale.

The Tammy has a good reputation and you're right, it's an excellent mix of price, quality and speed. Some other lenses you might consider:

Pentax DA 16-45mm f/4- This has just gone out of production but can still be found around for under $300 on closeout and in the $200-$250 range used. Not as fast as the Tammy of course. Excellent color and contrast. Very sharp at the wide end... just a touch soft at 45mm.

Pentax DA 17-70mm f/4 - again, not as fast as the Tammy but it does offer an extra 20mm at the long end over the Tammy and an extra 15mm over the kit lens. Includes SDM. Available for under $500.

Sigma 17-70mm f/2.8-4 DC Macro OS HSM - Same zoom range as the Pentax 17-70 and can also be found well under $500. As fast as the Tammy at the wide end and no slower than the Pentax at the long end. Also offers HSM which is considered somewhat more reliable than Pentax's SDM. At least up to now.

Pentax DA 18-250 or Tamron 18-250 (or newer 18-270) - I own the Pentax version and it's a surprisingly good lens. There are some compromises visible at the extreme ends but from 28-200mm, it's a peach. Of course, there's no advantage at the wide end over the kit lens. I would only recommend this if you want a one-lens solution for travelling.

Pentax DA 12-24 f/4 zoom - You mentioned this yourself. This is an excellent ultra wide-angle zoom. But it is big and heavy. Big enough to leave a shadow in images if you use the camera's built-in flash in indoor shots. If you have an external flash unit (either hotshoe mounted or off-camera), you'll be fine. Around $700.

Sigma 10-20mm f/4-5.6 EX DC HSM - An excellent second choice if you can't swing the Pentax 12-24. This lens has lots of fans and seems to be the third-party ultra wide-angle zoom of choice among Pentaxians. Can be had for under $500. Don't confuse this with the more-expensive Sigma 10-20mm zoom with the constant f/3.5 aperture and HSM (which is fine and faster but a lot more money).

Tamron 10-24mm f/3.5-4.5 SP Di II LD - This lens doesn't have quite as good a reputation as the Sigma 10-20mm but it's not junk and I've still seen a lot of nice images taken with it. It's also a bit faster than the Sigma and its zoom range is a bit longer, meaning you might not have to change lenses as often. Also can be had for under $500. If you can find it for substantially less than the Sigma, it could be a good deal and nice to pare with the Tammy 17-50.

Pentax DA 15mm f/4 Limited - An excellent wide-angle prime that you won't be sorry you own. Can now be found just under $500. This would also be the most compact option to pare with your kit lens.

Notice that many of these lenses would complement the Tamron 17-50. They would even complement the kit lens.

Hope this helps.

Marc Sabatella · 07-10-2010, 02:33 PM

Originally posted by edice

I was just comparing my P&S Panasonic Lumix DMC FX38 (4-22mm, f/2.8-5.9) and noticed that its as wide as my kit lens at 18mm, but can zoom in about twice as far. How does that work? Can the lens length only be compared with cameras of the same sensor size?

Yes. That's why you'll often see people using the phrase "35mm equivalent" in this context - meaning, the focal length that would produce the same field of view on a 35mm film camera. That's a way of "normalizing" focal lengths to make them comparable across systems. To convert your Pentax lenses to 35mm equivalent, multiply by the so-called "crop factor" 0f 1.5. So the 18mm is 27mm in "35mm equivalent" terms. For the Panasonic, apparently the crop factor must be around 7.

Quote:

And I've only seen a couple of churches - in the 17-50 section. The photos I could see myself taking in the 28-75mm section were all 35mm or 50mm, I didn't see many photos using the extra zoom.
But thats hard to tell, is there somewhere I can use to look at (eg) "all photos taken with focal length 70-75mm" ?

Why not use your Panasonic to evaluate this? 70mm works out to a "35mm equivalent" of 105mm. Divide that by 7 and that means you need to set the zoom lens on your Panasonic to 15mm to get the same FOV. Not that there is probably a direct way to do that, but most likely there is a way to find the current focal length of the lens (if nothing else, take a picture, then look at the focal length recorded in the EXIF). Then leave your zoom set there to see what it feels like.

edice · 07-11-2010, 01:55 AM

Wow! Great feedback, thanks everyone!

I looked through all the options and opinions, and I like the sound of two choices:

Tamron 17-50mm f/2.8, for the wide-angle and low-light across the whole range.

or

Sigma 17-70mm f/2.8-4, for the extra zoom at the end (although I lose some low-light).

I've checked the exim tags from my Panasonic, and determined that when it tells me "0.4m zoom" on the screen, it is approx equivalent to 70mm on my Pentax - thanks for that post, very informative.

I'll try and figure out if I really want that extra 20mm zoom, otherwise I guess the Tamron is the winner!

Now the next challenge... where to buy it from. Only B+H and Adorama list the Tammy with Pentax mount, I think. I'm in Perth, Australia and have sent emails to Vanbar, DigitalCameraWarehouse, CameraHouse and DigiDirect. Otherwise I could order from USA and get it posted over for cheaper, but I hope to get a good price from the local guys.

I have CRKennedy nearby, but it seems they don't sell to the public.

Is it preferable to buy from Australian suppliers for warranty claims etc? Or doesn't it matter much?

Biro · 07-13-2010, 09:04 PM

Originally posted by edice

Now the next challenge... where to buy it from. Only B+H and Adorama list the Tammy with Pentax mount, I think. I'm in Perth, Australia and have sent emails to Vanbar, DigitalCameraWarehouse, CameraHouse and DigiDirect. Otherwise I could order from USA and get it posted over for cheaper, but I hope to get a good price from the local guys.

I have CRKennedy nearby, but it seems they don't sell to the public.

Is it preferable to buy from Australian suppliers for warranty claims etc? Or doesn't it matter much?

I suspect if you bought a U.S. lens and needed to file a warranty claim, you'd have to send the lens back to the U.S. for any repair. Why not click on the link at the top of the page and ask the B&H representative on this forum?

07-09-2010, 09:32 AM	#1
edice New Member Join Date: Jul 2010 Photos: Gallery Posts: 3	Good lens for Kids + Travel Hi, I have a K100D, the 18-50mm kit lens and a fast Pentax 50mm 1.4 lens. Now I'm going on a 2 week Italian holiday and am looking for a lens that will work well with landscapes, churches, streets, people, me in front of interesting statues, AND also be useful once I get home to my 2-year-old kid. I find that I'm unable to take any sort of landscape shot, so wide would be good. I don't really feel the need to take a lot of detail-shots, so a strong zoom isn't a big priority although it would be nice from time to time. As I already have an 18-50mm lens, I'm not excited about getting another lens in the same field... although I am well aware of the limitations of my kit lens in indoor situations (ie near-hopeless without flash). So if its going to cover the same focal length, its going to need to be faster. Budget is enough for 1 decent lens of "reasonable price", so less than or around the US$500 rather than US$1000. Cheap is good, but I want a lens I will use and enjoy, not something to regret. I'm not a pro, so a really good lens might be wasted on me. I've crawled through this forum and a few others, and am thinking along these lines: DA 21mm f3.2 limited This seems to be touted as the "unobtrusive tourist lens", with good field of view and good speed, and excellent weight. But, won't my 18-50mm do the same job "acceptably" ? At 18mm the kit lens is f3.5... DA 12-24 f4 Nice and wide, and apparently as good as the 21mm. Pricey, and is it fast enough for indoor shots at Christmas? Pentax 18-250mm (3.5-6.5) Great all-round lens, but its as slow as my current kit lens, so no benefit at the wide end. Pentax/Bower 14mm F2.8 A bit too wide? I see a Bower on B+H. Tamron 17-50 f2.8 I read mixed reviews about the Tamrons, but most of the negatives seem to be about the bokeh. If I want that, I can use my 50mm f1.4... so would these be suitable for me? Tamron 10-24 f3.5-4.5 Cheaper than the Pentax, AND wider. Why not this lens? other lenses? i'm swimming in options but I'm not sure what would be appropriate... please help! thanks Paul

07-09-2010, 09:54 AM	#2
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,608	What about this lens: PentaxForums.com Third-Party Lens Review Database - Sigma 24-70mm F2.8 EX DG MACRO (AF Lens) Lens Reviews It's not as wide as your kit, but it's covers the entire 24-55mm range, and then some, and is 0.5 to 2 stops faster. It's also a full-frame lens and has macro capabilities as a bonus. I've used the Pentax 28-70mm (which is very comparable to the Sigma) as a walkaround, and have been quite satisfied! At 70mm, the lens was also very good for portraits (which I'm sure you take a lot of!). Adam PentaxForums.com Webmaster (Site Usage Guide \| Site Help \| My Photography) PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating or purchasing one of our Pentax eBooks. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

07-09-2010, 09:59 AM	#3
Ira Inactive Account Join Date: Mar 2009 Location: Coral Springs, FL Photos: Gallery \| Albums Posts: 5,216	I second Adam's range above, so also look at the 28-75 Tamron. Landscapes are one thing, so to expect a 14 to work for kids is a little unrealistic. But that being said, I never understood when people say they want a lens to shoot kids, because as far as I know, their reflections will indeed pass through the glass of a 14. Last edited by Ira; 07-09-2010 at 10:52 AM.

07-10-2010, 12:02 PM	#8
Biro Veteran Member Join Date: Jan 2009 Posts: 1,200	Originally posted by edice Thanks for the replies, this is really helping me. Side note: I was just comparing my P&S Panasonic Lumix DMC FX38 (4-22mm, f/2.8-5.9) and noticed that its as wide as my kit lens at 18mm, but can zoom in about twice as far. How does that work? Can the lens length only be compared with cameras of the same sensor size? That's right... the only way that Panasonic can enjoy a long focal zoom range like that is its tiny sensor. And I'm sure that camera will take fine images in good light. It's in low light and at high ISOs that the small sensor reveals its limitations. Originally posted by edice Back on topic, I'm thinking about the photos that I'd love to take and can't, and I'd have to say those are low light, and/or wide-angle such as family gatherings and landscapes. My previous "wife in front of nice church/mountain/city" photos are often just of a tiny part of the city - the finished photo doesn't give you a sense of scale. is the extra 1 mm going to make 17mm much wider than 18mm? It doesn't sound like much! While an extra few mm (or even 50mm) on the long end isn't as noticeable as you might think, it's quite a different situation at the wide end. 1mm may be pushing it... but 2, 3 or 4mm is quite noticeable. Originally posted by edice So, I like the idea of the Tamron 17-50 f/2.8, I agree that it would service most of my needs, and I don't see any other lens that give that sort of range and speed, especially at the wide end of the scale. The Tammy has a good reputation and you're right, it's an excellent mix of price, quality and speed. Some other lenses you might consider: Pentax DA 16-45mm f/4- This has just gone out of production but can still be found around for under $300 on closeout and in the $200-$250 range used. Not as fast as the Tammy of course. Excellent color and contrast. Very sharp at the wide end... just a touch soft at 45mm. Pentax DA 17-70mm f/4 - again, not as fast as the Tammy but it does offer an extra 20mm at the long end over the Tammy and an extra 15mm over the kit lens. Includes SDM. Available for under $500. Sigma 17-70mm f/2.8-4 DC Macro OS HSM - Same zoom range as the Pentax 17-70 and can also be found well under $500. As fast as the Tammy at the wide end and no slower than the Pentax at the long end. Also offers HSM which is considered somewhat more reliable than Pentax's SDM. At least up to now. Pentax DA 18-250 or Tamron 18-250 (or newer 18-270) - I own the Pentax version and it's a surprisingly good lens. There are some compromises visible at the extreme ends but from 28-200mm, it's a peach. Of course, there's no advantage at the wide end over the kit lens. I would only recommend this if you want a one-lens solution for travelling. Pentax DA 12-24 f/4 zoom - You mentioned this yourself. This is an excellent ultra wide-angle zoom. But it is big and heavy. Big enough to leave a shadow in images if you use the camera's built-in flash in indoor shots. If you have an external flash unit (either hotshoe mounted or off-camera), you'll be fine. Around $700. Sigma 10-20mm f/4-5.6 EX DC HSM - An excellent second choice if you can't swing the Pentax 12-24. This lens has lots of fans and seems to be the third-party ultra wide-angle zoom of choice among Pentaxians. Can be had for under $500. Don't confuse this with the more-expensive Sigma 10-20mm zoom with the constant f/3.5 aperture and HSM (which is fine and faster but a lot more money). Tamron 10-24mm f/3.5-4.5 SP Di II LD - This lens doesn't have quite as good a reputation as the Sigma 10-20mm but it's not junk and I've still seen a lot of nice images taken with it. It's also a bit faster than the Sigma and its zoom range is a bit longer, meaning you might not have to change lenses as often. Also can be had for under $500. If you can find it for substantially less than the Sigma, it could be a good deal and nice to pare with the Tammy 17-50. Pentax DA 15mm f/4 Limited - An excellent wide-angle prime that you won't be sorry you own. Can now be found just under $500. This would also be the most compact option to pare with your kit lens. Notice that many of these lenses would complement the Tamron 17-50. They would even complement the kit lens. Hope this helps. Last edited by Biro; 07-10-2010 at 02:37 PM.

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07-09-2010, 10:22 AM	#4
bdery Pentaxian Join Date: Mar 2008 Location: Quebec city, Canada Photos: Gallery Posts: 9,362	DA 21mm f3.2 limited The 21 is way better than the kit lens. I own it and it complements my F50 f1,7 perfectly as a low light task force. It's small and light enough to be handheld for indoors shots without flash. It would be a good choice. DA 12-24 f4 F4 isn't fast enough for indoor shots without flash, I'd say. Pentax 18-250mm (3.5-6.5) Would be a horrible choice for inside of buildings in Italy. I've been there (with a P&S at the time) and I yearned for a faster lens. Pentax/Bower 14mm F2.8 Very wide. Your call. Tamron 17-50 f2.8 Supposed to be great. Tamron 10-24 f3.5-4.5 No opinon. The Tamron 28-75 would be a good choice too. It really boils down to your shooting style. I personally use the Sigma 17-70 for everyday shots, and carry the 21 and 50 for low light. That's how I work. Your way of working must be different, and no one knows you better than you

07-10-2010, 12:04 AM	#5
edice New Member Join Date: Jul 2010 Photos: Gallery Posts: 3 Original Poster	Thanks for the replies, this is really helping me. Side note: I was just comparing my P&S Panasonic Lumix DMC FX38 (4-22mm, f/2.8-5.9) and noticed that its as wide as my kit lens at 18mm, but can zoom in about twice as far. How does that work? Can the lens length only be compared with cameras of the same sensor size? Back on topic, I'm thinking about the photos that I'd love to take and can't, and I'd have to say those are low light, and/or wide-angle such as family gatherings and landscapes. My previous "wife in front of nice church/mountain/city" photos are often just of a tiny part of the city - the finished photo doesn't give you a sense of scale. is the extra 1 mm going to make 17mm much wider than 18mm? It doesn't sound like much! So, I like the idea of the Tamron 17-50 f/2.8, I agree that it would service most of my needs, and I don't see any other lens that give that sort of range and speed, especially at the wide end of the scale. I looked through the photos found here: 17-50mm: Tamron SP AF 17-50mm f/2.8 XR Di-II LD Asp IF Lens Sample Photos and Specifications 28-75mm: Tamron SP AF 28-75mm f/2.8 XR Di LD (IF) Lens Sample Photos and Specifications And I've only seen a couple of churches - in the 17-50 section. The photos I could see myself taking in the 28-75mm section were all 35mm or 50mm, I didn't see many photos using the extra zoom. But thats hard to tell, is there somewhere I can use to look at (eg) "all photos taken with focal length 70-75mm" ? So far the 17-50mm looks like the one! thanks, Paul

07-10-2010, 07:57 AM	#6
bdery Pentaxian Join Date: Mar 2008 Location: Quebec city, Canada Photos: Gallery Posts: 9,362	17 vs 18 will be much more noticeable than, say, 200 vs 201. So yeah, you'll notice it. Regarding your "side note" question, there's about an infinite number of ways to design a lens. If you make a zoom lens starting at 18 mm, you can have it rach 25, 100, 250 mm if you want. OF COURSE there are always compromises when designing lenses. The longer the reach, the more compromises you have to make. But the focal length range itself is not limited.

07-10-2010, 11:03 AM	#7
pb_red Senior Member Join Date: Jan 2007 Location: Seattle Posts: 194	edice, welcome to the forum! first, if you have the pentax kit lens then it's an 18-55mm, not 18-50. in any case, i've been thinking about what i want in a travel lens for a while and it's definitely a zoom lens since as much as i like primes they are just not versatile enough when traveling with others who don't want to stop and wait for you to change lenses all the time. also, while the 18-55mm is actually a pretty darn good lens it's just not as wide as i'd like or as long as it'd like sometimes. so the main lenses i considered were the 18-200's, 18-250's, and 17-70's. i went with a 17-70 because i prefer to shoot wide angle so that extra 1mm over stock makes a difference and the extra 15mm on the long end is nice as well. i just could not imagine taking many photos in the 70-250 range so i ignored the superzooms. i went with the pentax lens over sigma because i like the constant f4 aperture. i hope you find this info useful and good luck with whatever you chose.

07-10-2010, 02:33 PM	#9
Marc Sabatella Veteran Member Join Date: Sep 2006 Location: Denver, CO Photos: Gallery Posts: 10,685	Originally posted by edice I was just comparing my P&S Panasonic Lumix DMC FX38 (4-22mm, f/2.8-5.9) and noticed that its as wide as my kit lens at 18mm, but can zoom in about twice as far. How does that work? Can the lens length only be compared with cameras of the same sensor size? Yes. That's why you'll often see people using the phrase "35mm equivalent" in this context - meaning, the focal length that would produce the same field of view on a 35mm film camera. That's a way of "normalizing" focal lengths to make them comparable across systems. To convert your Pentax lenses to 35mm equivalent, multiply by the so-called "crop factor" 0f 1.5. So the 18mm is 27mm in "35mm equivalent" terms. For the Panasonic, apparently the crop factor must be around 7. Quote: And I've only seen a couple of churches - in the 17-50 section. The photos I could see myself taking in the 28-75mm section were all 35mm or 50mm, I didn't see many photos using the extra zoom. But thats hard to tell, is there somewhere I can use to look at (eg) "all photos taken with focal length 70-75mm" ? Why not use your Panasonic to evaluate this? 70mm works out to a "35mm equivalent" of 105mm. Divide that by 7 and that means you need to set the zoom lens on your Panasonic to 15mm to get the same FOV. Not that there is probably a direct way to do that, but most likely there is a way to find the current focal length of the lens (if nothing else, take a picture, then look at the focal length recorded in the EXIF). Then leave your zoom set there to see what it feels like.

07-11-2010, 01:55 AM	#10
edice New Member Join Date: Jul 2010 Photos: Gallery Posts: 3 Original Poster	Wow! Great feedback, thanks everyone! I looked through all the options and opinions, and I like the sound of two choices: Tamron 17-50mm f/2.8, for the wide-angle and low-light across the whole range. or Sigma 17-70mm f/2.8-4, for the extra zoom at the end (although I lose some low-light). I've checked the exim tags from my Panasonic, and determined that when it tells me "0.4m zoom" on the screen, it is approx equivalent to 70mm on my Pentax - thanks for that post, very informative. I'll try and figure out if I really want that extra 20mm zoom, otherwise I guess the Tamron is the winner! Now the next challenge... where to buy it from. Only B+H and Adorama list the Tammy with Pentax mount, I think. I'm in Perth, Australia and have sent emails to Vanbar, DigitalCameraWarehouse, CameraHouse and DigiDirect. Otherwise I could order from USA and get it posted over for cheaper, but I hope to get a good price from the local guys. I have CRKennedy nearby, but it seems they don't sell to the public. Is it preferable to buy from Australian suppliers for warranty claims etc? Or doesn't it matter much?

07-13-2010, 09:04 PM	#11
Biro Veteran Member Join Date: Jan 2009 Posts: 1,200	Originally posted by edice Now the next challenge... where to buy it from. Only B+H and Adorama list the Tammy with Pentax mount, I think. I'm in Perth, Australia and have sent emails to Vanbar, DigitalCameraWarehouse, CameraHouse and DigiDirect. Otherwise I could order from USA and get it posted over for cheaper, but I hope to get a good price from the local guys. I have CRKennedy nearby, but it seems they don't sell to the public. Is it preferable to buy from Australian suppliers for warranty claims etc? Or doesn't it matter much? I suspect if you bought a U.S. lens and needed to file a warranty claim, you'd have to send the lens back to the U.S. for any repair. Why not click on the link at the top of the page and ask the B&H representative on this forum?