constant aperature or focal length?

cali92rs · 02-04-2013, 03:33 PM

Originally posted by PBandJ

Thanks for the explanation. The difference between these 2 is more important than I thought!

It depends (like everything else in photography).
If you are shooting mostly outside, in the sunshine then 1.5 stops may not come into play much at all, especially if you have SR and if you are shooting with a K-5 where you can shoot up to ISO1600 with little consequence.

Buuuuut, if you are shooting indoors, handheld in poor lighting conditions where every photon of light is precious then yes, 1.5 stops can make or break you.

VoiceOfReason · 02-04-2013, 04:18 PM

That Tamron 17-50 is decent wide open, and very sharp at 5.6. Stick with it, then get something longer to take up where it left off.

kevinf7 · 02-04-2013, 06:24 PM

I agree get the 17-50. Personally I prefer better IQ over the extra 20mm at the long end.

**ivanvernon** · 02-04-2013, 06:59 PM

Originally posted by Adam

The Tamron lens is going to give you much better IQ I would say. Overall I would also go for a 17-70mm because of its convenience, but I would wait for the new Sigma 17-70mm F2.8-4 C, which is going to deliver better IQ than the old version (plus it has HSM).

IQ on this Tam 17-50 is surprising me with its excellence. It is almost like carrying a prime/zoom lens. Its low-light performance attached to the K-7 is also remarkable. However, the same inside low-light shots with the Tam 17-50 attached to the K-10 are surprisingly/comparatively poor, lots of yellowing out. I know the K-7 has lots more ISO to give, but I am wondering what other factors may be in play here?

joe.penn · 02-04-2013, 07:24 PM

Originally posted by PBandJ

The 10-20 should be here this week, keeping fingers crossed. I'm hoping that the 10-20 will be my main walkabout.

DC Shooting? I frequent DC often (well, more than often, down there all of the time). I have shot with everything in DC - UWA lenses, 15mm, 30mm, 35mm, *200, *50~135, 70-200, all while weaving in and out of traffic on my mini-[long]-board. I used to love popping up on random people and shooting a random with the *50~135 (ya, i'm not discreet one bit)

. The 17~50 2.8 is a good choice, I would go with smaller faster primes though if you are talking about shooting in bldgs downtown, most of those historic places/bldg's have very dim lighting [purposely].

PBandJ · 02-04-2013, 07:49 PM

Oh that's you??? j/k
I'm actually on the MD side of DC too..
I have a DA 35/2.4. I was actually think of something for a main walkabout when travelling.
I think I will zoom with my feet using that if I need 50mm faster than the 17-70 can provide. Or maybe I just get a cheap A 50/f2.

Originally posted by joe.penn

DC Shooting? I frequent DC often (well, more than often, down there all of the time). I have shot with everything in DC - UWA lenses, 15mm, 30mm, 35mm, *200, *50~135, 70-200, all while weaving in and out of traffic on my mini-[long]-board. I used to love popping up on random people and shooting a random with the *50~135 (ya, i'm not discreet one bit)

. The 17~50 2.8 is a good choice, I would go with smaller faster primes though if you are talking about shooting in bldgs downtown, most of those historic places/bldg's have very dim lighting [purposely].

joe.penn · 02-04-2013, 07:52 PM

Originally posted by PBandJ

I'm actually on the MD side of DC too..

I am in Southern Maryland, straight down Rt4 (Pennsylvania Ave). When I am not out on the water shooting, I am in DC having fun shooting...

PBandJ · 02-04-2013, 07:55 PM

Originally posted by joe.penn

I am in Southern Maryland, straight down Rt4 (Pennsylvania Ave). When I am not out on the water shooting, I am in DC having fun shooting...

Lucky you! i'm in the Bethesda side

joe.penn · 02-04-2013, 08:03 PM

Originally posted by PBandJ

Lucky you! i'm in the Bethesda side

Your on the north side - there is some really good landscape opportunities up 270, also great falls and harpers ferry is great during fall time (actually anytime there is good shooting up that way). I have the chesapeake bay on one side of me and the patuxent river on the other side along with some of the best parks in the state all around me. I still love DC though, greatest city in the world IMHO...

SpecialK · 02-04-2013, 09:41 PM

For a single casual catch-as-catch-can, i.e., "walk around" lens, I would choose FL over f.

sam-joseph · 02-04-2013, 10:21 PM

Hey Miss PBandJ,
How about this one : Tamron 28-75mm F2.8 AF XR Di LD Macro SP
You've got the 10-20, and the Tamron gets a good write-up here. It's not too expensive, constant f2.8 and a bit longer than the 50.
All good.

Regards

ruoyun.huang · 02-05-2013, 01:45 AM

I have been thinking of the same thing for long time as well.

seriously, get both!

PBandJ · 02-05-2013, 05:49 AM

Thanks all. I've decided to get the used Sigma 17-70 version 1 (non HSM) and try it out, along with the Sigma 10-20 (which I really really want). There are pros and cons to each choice.
It will be better to spend a little less money at the beginning and find out what I want and need in real life vs specs on paper, and then get something different if I find that what I have isn't working for me.

PBandJ · 02-05-2013, 05:51 AM

Originally posted by sam-joseph

Hey Miss PBandJ,
How about this one : Tamron 28-75mm F2.8 AF XR Di LD Macro SP
You've got the 10-20, and the Tamron gets a good write-up here. It's not too expensive, constant f2.8 and a bit longer than the 50.
All good.

Regards

FYI: There is one in the B&H used section today. I'm going to pass on it and stick with the Sigma 17-70 right now. The fixed aperture is nice, but I want 1 lens to cover the 17-50 area.

**ivanvernon** · 02-05-2013, 08:00 AM

Good luck to you. I hope these lens choices work out just the way you like. I hope you will get image quality as good as my tam 17-50, while I envy your extra 20mm!

02-05-2013, 08:00 AM	#30
ivanvernon Loyal Site Supporter Join Date: Oct 2012 Location: Medina, OH Photos: Albums Posts: 7,224	Good luck with sigma choice Good luck to you. I hope these lens choices work out just the way you like. I hope you will get image quality as good as my tam 17-50, while I envy your extra 20mm!

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02-04-2013, 03:33 PM	#16
cali92rs Veteran Member Join Date: May 2011 Location: Long Beach, CA Posts: 3,354	Originally posted by PBandJ Thanks for the explanation. The difference between these 2 is more important than I thought! It depends (like everything else in photography). If you are shooting mostly outside, in the sunshine then 1.5 stops may not come into play much at all, especially if you have SR and if you are shooting with a K-5 where you can shoot up to ISO1600 with little consequence. Buuuuut, if you are shooting indoors, handheld in poor lighting conditions where every photon of light is precious then yes, 1.5 stops can make or break you.

02-04-2013, 04:18 PM	#17
VoiceOfReason Site Supporter Join Date: Jun 2010 Location: Mishawaka IN area Photos: Albums Posts: 6,124	That Tamron 17-50 is decent wide open, and very sharp at 5.6. Stick with it, then get something longer to take up where it left off.

02-04-2013, 06:24 PM	#18
kevinf7 New Member Join Date: Oct 2011 Posts: 8	I agree get the 17-50. Personally I prefer better IQ over the extra 20mm at the long end.

02-04-2013, 06:59 PM	#19
ivanvernon Loyal Site Supporter Join Date: Oct 2012 Location: Medina, OH Photos: Albums Posts: 7,224	Originally posted by Adam The Tamron lens is going to give you much better IQ I would say. Overall I would also go for a 17-70mm because of its convenience, but I would wait for the new Sigma 17-70mm F2.8-4 C, which is going to deliver better IQ than the old version (plus it has HSM). IQ on this Tam 17-50 is surprising me with its excellence. It is almost like carrying a prime/zoom lens. Its low-light performance attached to the K-7 is also remarkable. However, the same inside low-light shots with the Tam 17-50 attached to the K-10 are surprisingly/comparatively poor, lots of yellowing out. I know the K-7 has lots more ISO to give, but I am wondering what other factors may be in play here?

02-04-2013, 07:24 PM	#20
joe.penn Veteran Member Join Date: Mar 2011 Location: Maryland (Right Outside Washington DC) Photos: Gallery \| Albums Posts: 2,902	Originally posted by PBandJ The 10-20 should be here this week, keeping fingers crossed. I'm hoping that the 10-20 will be my main walkabout. DC Shooting? I frequent DC often (well, more than often, down there all of the time). I have shot with everything in DC - UWA lenses, 15mm, 30mm, 35mm, 200, 50~135, 70-200, all while weaving in and out of traffic on my mini-[long]-board. I used to love popping up on random people and shooting a random with the *50~135 (ya, i'm not discreet one bit) . The 17~50 2.8 is a good choice, I would go with smaller faster primes though if you are talking about shooting in bldgs downtown, most of those historic places/bldg's have very dim lighting [purposely].

02-04-2013, 07:49 PM	#21
PBandJ Veteran Member Join Date: Jan 2013 Location: Washington DC metro area Photos: Gallery Posts: 480 Original Poster	Oh that's you??? j/k I'm actually on the MD side of DC too.. I have a DA 35/2.4. I was actually think of something for a main walkabout when travelling. I think I will zoom with my feet using that if I need 50mm faster than the 17-70 can provide. Or maybe I just get a cheap A 50/f2. Originally posted by joe.penn DC Shooting? I frequent DC often (well, more than often, down there all of the time). I have shot with everything in DC - UWA lenses, 15mm, 30mm, 35mm, 200, 50~135, 70-200, all while weaving in and out of traffic on my mini-[long]-board. I used to love popping up on random people and shooting a random with the *50~135 (ya, i'm not discreet one bit) . The 17~50 2.8 is a good choice, I would go with smaller faster primes though if you are talking about shooting in bldgs downtown, most of those historic places/bldg's have very dim lighting [purposely].

02-04-2013, 07:52 PM	#22
joe.penn Veteran Member Join Date: Mar 2011 Location: Maryland (Right Outside Washington DC) Photos: Gallery \| Albums Posts: 2,902	Originally posted by PBandJ I'm actually on the MD side of DC too.. I am in Southern Maryland, straight down Rt4 (Pennsylvania Ave). When I am not out on the water shooting, I am in DC having fun shooting...

02-04-2013, 07:55 PM	#23
PBandJ Veteran Member Join Date: Jan 2013 Location: Washington DC metro area Photos: Gallery Posts: 480 Original Poster	Originally posted by joe.penn I am in Southern Maryland, straight down Rt4 (Pennsylvania Ave). When I am not out on the water shooting, I am in DC having fun shooting... Lucky you! i'm in the Bethesda side

02-04-2013, 08:03 PM	#24
joe.penn Veteran Member Join Date: Mar 2011 Location: Maryland (Right Outside Washington DC) Photos: Gallery \| Albums Posts: 2,902	Originally posted by PBandJ Lucky you! i'm in the Bethesda side Your on the north side - there is some really good landscape opportunities up 270, also great falls and harpers ferry is great during fall time (actually anytime there is good shooting up that way). I have the chesapeake bay on one side of me and the patuxent river on the other side along with some of the best parks in the state all around me. I still love DC though, greatest city in the world IMHO...

02-04-2013, 09:41 PM	#25
SpecialK Pentaxian Join Date: Dec 2006 Location: So California Photos: Gallery Posts: 16,481	For a single casual catch-as-catch-can, i.e., "walk around" lens, I would choose FL over f.

02-04-2013, 10:21 PM	#26
sam-joseph Veteran Member Join Date: Oct 2009 Location: Newcastle, NSW, Australia Photos: Gallery Posts: 1,086	Hey Miss PBandJ, How about this one : Tamron 28-75mm F2.8 AF XR Di LD Macro SP You've got the 10-20, and the Tamron gets a good write-up here. It's not too expensive, constant f2.8 and a bit longer than the 50. All good. Regards

02-05-2013, 01:45 AM	#27
ruoyun.huang Forum Member Join Date: Dec 2008 Location: Seattle, WA Posts: 64	I have been thinking of the same thing for long time as well. seriously, get both!

02-05-2013, 05:49 AM	#28
PBandJ Veteran Member Join Date: Jan 2013 Location: Washington DC metro area Photos: Gallery Posts: 480 Original Poster	Thanks all. I've decided to get the used Sigma 17-70 version 1 (non HSM) and try it out, along with the Sigma 10-20 (which I really really want). There are pros and cons to each choice. It will be better to spend a little less money at the beginning and find out what I want and need in real life vs specs on paper, and then get something different if I find that what I have isn't working for me.

02-05-2013, 05:51 AM	#29
PBandJ Veteran Member Join Date: Jan 2013 Location: Washington DC metro area Photos: Gallery Posts: 480 Original Poster	Originally posted by sam-joseph Hey Miss PBandJ, How about this one : Tamron 28-75mm F2.8 AF XR Di LD Macro SP You've got the 10-20, and the Tamron gets a good write-up here. It's not too expensive, constant f2.8 and a bit longer than the 50. All good. Regards FYI: There is one in the B&H used section today. I'm going to pass on it and stick with the Sigma 17-70 right now. The fixed aperture is nice, but I want 1 lens to cover the 17-50 area.