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**NaClH2O** · 04-03-2013, 08:35 AM

I've a question on the old sigma 17-70, not the HSM one, but the screw drive focused one. Does anyone know if that lens was made for a FF image circle or the ASP-C image circle? I'm thinking of selling mine but will wait if it's a FF lens.

NaCl(it would be worth a lot more if FF when the FF body comes out)H2O

langkata · 04-03-2013, 10:07 AM

It's a DC lens so intended for APS-C. I haven't tried to use mine on a film camera but would expect heavy vignetting throughout the zoom range.

bdery · 04-03-2013, 10:31 AM

It is made for APS-C. I have mounted it on a film camera and the cornerrs were black in the viewfinder. That's more than vigneting, that's cropping.

Kozlok · 04-03-2013, 11:50 AM

Why are you thinking of selling it? It's on my list of maybes for a walk around zoom (with the 18-135 having the slight edge at the moment)

karpati · 04-03-2013, 01:13 PM

I exposed a small scrap of old photographic paper in a ME Super with the 17-70 mounted. There's vignetting to say the least, but its minimal at 70mm.

jamarley · 04-03-2013, 01:55 PM

I've been trying to figure this out since I got this lens (about 2 years). I haven't been able to afford better lenses, so this spends a lot of time on my K5 and I'm usually really pleased with it's performance. I just took a look at a DNG taken with this lens in Zoner Photo Studio - it reported Focal length 70.00 mm, but Focal length (EQ35mm) 105 mm! That makes it sound like it al least acts like a FF lens on APS-C cameras. And yes, I've read it exhibits vignetting on FF.

twitch · 04-03-2013, 02:20 PM

Originally posted by jamarley

it reported Focal length 70.00 mm, but Focal length (EQ35mm) 105 mm! That makes it sound like it al least acts like a FF lens on APS-C cameras.

Actually it doesn't mean that, any camera and lens can have it's focal length expressed as a EQ 35mm focal length, no matter how big or small its image circle. The Sig 17-70 is definitely not a FF lens, not even close.

jamarley · 04-03-2013, 03:58 PM

Originally posted by twitch

Actually it doesn't mean that, any camera and lens can have it's focal length expressed as a EQ 35mm focal length, no matter how big or small its image circle. The Sig 17-70 is definitely not a FF lens, not even close.

Well now that's settled. At least I know now it's my widest lens. Thanks for the clarification.

**NaClH2O** · 04-04-2013, 06:16 AM

Originally posted by Kozlok

Why are you thinking of selling it? It's on my list of maybes for a walk around zoom (with the 18-135 having the slight edge at the moment)

I never use it. I bought it 5 years ago back when I was traveling some for business and wanted a two lens kit for traveling; coupled with my Pentax A 70-210. It was a perfect kit for that but tnen I stopped traveling. I've other lenses in that range that I like better so it's been gathering dust and getting lonely. Since it's an ASP-C lens I'll be putting it up in the marketplace at the end of the month. Until then it will be my "Single in April" lens.

NaCl(that way I'll have plenty of samples to show folks)H2O

04-03-2013, 08:35 AM	#1
NaClH2O Site Supporter Join Date: Sep 2006 Location: Bronx NY Photos: Gallery \| Albums Posts: 5,631	Old Sigma 17-70mm F/2.8-4.5 I've a question on the old sigma 17-70, not the HSM one, but the screw drive focused one. Does anyone know if that lens was made for a FF image circle or the ASP-C image circle? I'm thinking of selling mine but will wait if it's a FF lens. NaCl(it would be worth a lot more if FF when the FF body comes out)H2O

04-03-2013, 01:13 PM	#5
karpati New Member Join Date: Oct 2008 Location: Hastings, UK Posts: 18	I exposed a small scrap of old photographic paper in a ME Super with the 17-70 mounted. There's vignetting to say the least, but its minimal at 70mm. Attached Images

04-04-2013, 06:16 AM	#9
NaClH2O Site Supporter Join Date: Sep 2006 Location: Bronx NY Photos: Gallery \| Albums Posts: 5,631 Original Poster	Originally posted by Kozlok Why are you thinking of selling it? It's on my list of maybes for a walk around zoom (with the 18-135 having the slight edge at the moment) I never use it. I bought it 5 years ago back when I was traveling some for business and wanted a two lens kit for traveling; coupled with my Pentax A 70-210. It was a perfect kit for that but tnen I stopped traveling. I've other lenses in that range that I like better so it's been gathering dust and getting lonely. Since it's an ASP-C lens I'll be putting it up in the marketplace at the end of the month. Until then it will be my "Single in April" lens. NaCl(that way I'll have plenty of samples to show folks)H2O Last edited by NaClH2O; 04-04-2013 at 06:16 AM. Reason: punctuation

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04-03-2013, 10:07 AM	#2
langkata Forum Member Join Date: Jun 2012 Location: Baton Rouge Photos: Albums Posts: 68	It's a DC lens so intended for APS-C. I haven't tried to use mine on a film camera but would expect heavy vignetting throughout the zoom range.

04-03-2013, 10:31 AM	#3
bdery Pentaxian Join Date: Mar 2008 Location: Quebec city, Canada Photos: Gallery Posts: 9,363	It is made for APS-C. I have mounted it on a film camera and the cornerrs were black in the viewfinder. That's more than vigneting, that's cropping.

04-03-2013, 11:50 AM	#4
Kozlok Pentaxian Join Date: Jun 2012 Location: Albuquerque Photos: Gallery Posts: 3,148	Why are you thinking of selling it? It's on my list of maybes for a walk around zoom (with the 18-135 having the slight edge at the moment)

04-03-2013, 01:55 PM	#6
jamarley Site Supporter Join Date: Dec 2010 Location: New Jersey Photos: Gallery Posts: 409	I've been trying to figure this out since I got this lens (about 2 years). I haven't been able to afford better lenses, so this spends a lot of time on my K5 and I'm usually really pleased with it's performance. I just took a look at a DNG taken with this lens in Zoner Photo Studio - it reported Focal length 70.00 mm, but Focal length (EQ35mm) 105 mm! That makes it sound like it al least acts like a FF lens on APS-C cameras. And yes, I've read it exhibits vignetting on FF.

04-03-2013, 02:20 PM	#7
twitch Veteran Member Join Date: Nov 2009 Posts: 4,571	Originally posted by jamarley it reported Focal length 70.00 mm, but Focal length (EQ35mm) 105 mm! That makes it sound like it al least acts like a FF lens on APS-C cameras. Actually it doesn't mean that, any camera and lens can have it's focal length expressed as a EQ 35mm focal length, no matter how big or small its image circle. The Sig 17-70 is definitely not a FF lens, not even close.

04-03-2013, 03:58 PM	#8
jamarley Site Supporter Join Date: Dec 2010 Location: New Jersey Photos: Gallery Posts: 409	Originally posted by twitch Actually it doesn't mean that, any camera and lens can have it's focal length expressed as a EQ 35mm focal length, no matter how big or small its image circle. The Sig 17-70 is definitely not a FF lens, not even close. Well now that's settled. At least I know now it's my widest lens. Thanks for the clarification.

Old Sigma 17-70mm F/2.8-4.5

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