what SR focal length for smc-a 50 1.4?

rvkssl · 11-21-2008, 08:03 AM

Hi!,

Just got my smc-a 50mm 1.4 lens for my K10d, and i was wondering what focal lenght to enter for my shake reduction?, is it 50 mm or 75 mm for the 1.5 correction factor?

By the way, I bought this lens thanks to this forum and your feedback, it feels pretty though and solid compared to the standard kit lens, let's hope i'll get the same amazing pictures out of it like some of you did

Regards,

Ronald

MrApollinax · 11-21-2008, 08:09 AM

Use the 50mm focal length. the 1.5 crop factor does not change the physical distance of the lens from the focal plane.

MPrince · 11-21-2008, 08:09 AM

Welcome to the forum!

The focal length length is 50, so you use 50. The crop factor exists because of the size of the sensor, not because of anything about the lens itself. Focal length is focal length. What is affected is the field of view. The field of view on a 50mm lens used on a aps-c sensor digital camera is equivalent to the field of view of a 75mm lens used on a film camera.

Put another way, take a photo with a 50mm lens on digital and the same lens on camera. No change in focal length, but the field of view will be different. You will have a narrower field of view with the digital than with the film.

Hope that helps.

Wheatfield · 11-21-2008, 08:37 AM

Originally posted by rvkssl

Hi!,

Just got my smc-a 50mm 1.4 lens for my K10d, and i was wondering what focal lenght to enter for my shake reduction?, is it 50 mm or 75 mm for the 1.5 correction factor?

By the way, I bought this lens thanks to this forum and your feedback, it feels pretty though and solid compared to the standard kit lens, let's hope i'll get the same amazing pictures out of it like some of you did

Regards,

Ronald

Set the shake reduction for the marked focal length. Manufacturers do it that way to keep things as simple as possible.

pingflood · 11-21-2008, 10:46 AM

Yep, set it to the focal length. A 50mm is a 50mm is a 50mm, period. It's a "normal" on 35mm format, a "short tele" on APS-C, a "wide" on 6x6, an "ultrawide" on 4x5 etc etc.. but the focal length remains the same. Not sure who started the "equivalent" thing, but whatever marketing/PR/whatnot team needs to be shot.

rvkssl · 11-21-2008, 11:38 AM

Thanks guy's , this makes sence to me!

Ronald

**Kerrowdown** · 11-21-2008, 04:13 PM

Yep as the others guys say (all too quick for me) set to 50.

11-21-2008, 08:03 AM	#1
rvkssl Inactive Account Join Date: Nov 2008 Location: Venray, Netherlands Posts: 6	what SR focal length for smc-a 50 1.4? Hi!, Just got my smc-a 50mm 1.4 lens for my K10d, and i was wondering what focal lenght to enter for my shake reduction?, is it 50 mm or 75 mm for the 1.5 correction factor? By the way, I bought this lens thanks to this forum and your feedback, it feels pretty though and solid compared to the standard kit lens, let's hope i'll get the same amazing pictures out of it like some of you did Regards, Ronald

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11-21-2008, 08:09 AM	#2
MrApollinax Veteran Member Join Date: Apr 2008 Location: Minnesota Photos: Gallery Posts: 1,529	Use the 50mm focal length. the 1.5 crop factor does not change the physical distance of the lens from the focal plane.

11-21-2008, 08:09 AM	#3
MPrince Veteran Member Join Date: Sep 2006 Location: WV Posts: 1,495	Welcome to the forum! The focal length length is 50, so you use 50. The crop factor exists because of the size of the sensor, not because of anything about the lens itself. Focal length is focal length. What is affected is the field of view. The field of view on a 50mm lens used on a aps-c sensor digital camera is equivalent to the field of view of a 75mm lens used on a film camera. Put another way, take a photo with a 50mm lens on digital and the same lens on camera. No change in focal length, but the field of view will be different. You will have a narrower field of view with the digital than with the film. Hope that helps.

11-21-2008, 08:37 AM	#4
Wheatfield Moderator Join Date: Apr 2008 Location: The wheatfields of Canada Posts: 15,981	Originally posted by rvkssl Hi!, Just got my smc-a 50mm 1.4 lens for my K10d, and i was wondering what focal lenght to enter for my shake reduction?, is it 50 mm or 75 mm for the 1.5 correction factor? By the way, I bought this lens thanks to this forum and your feedback, it feels pretty though and solid compared to the standard kit lens, let's hope i'll get the same amazing pictures out of it like some of you did Regards, Ronald Set the shake reduction for the marked focal length. Manufacturers do it that way to keep things as simple as possible.

11-21-2008, 10:46 AM	#5
pingflood Veteran Member Join Date: Jun 2008 Location: Borås, Sweden Photos: Gallery Posts: 3,169	Yep, set it to the focal length. A 50mm is a 50mm is a 50mm, period. It's a "normal" on 35mm format, a "short tele" on APS-C, a "wide" on 6x6, an "ultrawide" on 4x5 etc etc.. but the focal length remains the same. Not sure who started the "equivalent" thing, but whatever marketing/PR/whatnot team needs to be shot.

11-21-2008, 11:38 AM	#6
rvkssl Inactive Account Join Date: Nov 2008 Location: Venray, Netherlands Posts: 6 Original Poster	Thanks guy's , this makes sence to me! Ronald

11-21-2008, 04:13 PM	#7
Kerrowdown PEG Moderator Join Date: Aug 2008 Location: Highlands of Scotland... "Hold Infinity in the palm of your hand" - William Blake Photos: Gallery Posts: 57,819	Yep as the others guys say (all too quick for me) set to 50.