Win a Pentax Limited Lens: Raffle Now Live!

AdrianM · 09-21-2016, 03:09 AM - **1 Like**

My newly acquired Sigma 35 Art has just arrived, but I noticed that on the K-1 it defaults to cropped sensor mode. While this can easily be fixed by forcing the camera to use Full Frame mode, I was wondering if there is a fix for this somewhere. So, hoping that another K-1 owner has already seen this and has an answer.

...and for info: I haven't got the USB dock (yet) but it would be great to know that it would solve the problem before I raced out to buy.

Thanks in advance for your help.

Adam · 09-21-2016, 03:13 AM - **1 Like**

Not that I know of, but Sigma has acknowledged the issue. Perhaps they'll release a firmware update to fix it at some point.

Medex · 09-21-2016, 05:02 AM

Originally posted by AdrianM

My newly acquired Sigma 35 Art has just arrived, but I noticed that on the K-1 it defaults to cropped sensor mode. While this can easily be fixed by forcing the camera to use Full Frame mode, I was wondering if there is a fix for this somewhere. So, hoping that another K-1 owner has already seen this and has an answer.

...and for info: I haven't got the USB dock (yet) but it would be great to know that it would solve the problem before I raced out to buy.

Thanks in advance for your help.

why you need the dock for fixed focal lenght lens? You can make microadjustment in camera Menu.

mee · 09-21-2016, 05:25 AM - **1 Like**

Originally posted by Medex

why you need the dock for fixed focal lenght lens? You can make microadjustment in camera Menu.

His issue isn't front or back focusing but that the camera body senses the DG (Full Frame) lens as a DC (APS-C) on the K-1

Sigma sends lens firmwares through the dock.. in addition to micro adjustments.

banep · 09-21-2016, 08:09 AM

Originally posted by AdrianM

My newly acquired Sigma 35 Art has just arrived, but I noticed that on the K-1 it defaults to cropped sensor mode. While this can easily be fixed by forcing the camera to use Full Frame mode, I was wondering if there is a fix for this somewhere. So, hoping that another K-1 owner has already seen this and has an answer.
.

I have similar problem with some other Sigma autofocus full frame lenses on K-1.
Looks like camera can't identify lens and activate crop mode by default.
Or maybe it is the problem of brilliant Sigma reverse engineering.
Firmware update is probably the only solution, lens needs another id.

p.s. I'm pretty much pissed off on those Sigma K mount lenses. Some of them are not working (like 70-200), some of them have ID of my existing Pentax lenses and mess my micro focusing for those lenses, some of them are not recognized as full frame, local support is disaster, etc,etc... I think I'll sell them all and never buy Sigma again.

Paul2660 · 09-21-2016, 07:01 PM

I have the Sigma 35mm 1.4 and it works as it should, comes up in full frame mode. If possible you might see if you can exchange the lens for a different one. I have not updated the lens firmware since I purchased the lens 2 months ago.

Looking forward to the Samyang 20mm 1.4 also, but guess it won't ship for a while yet.

Paul C

AdrianM · 09-22-2016, 02:17 AM

Originally posted by Paul2660

I have the Sigma 35mm 1.4 and it works as it should, comes up in full frame mode. If possible you might see if you can exchange the lens for a different one. I have not updated the lens firmware since I purchased the lens 2 months ago.

Looking forward to the Samyang 20mm 1.4 also, but guess it won't ship for a while yet.

Paul C

Thanks, Paul. Can you confirm for me that you have the Crop Mode as "Auto" and the lens registers as full frame ? Just want to be clear if I have a conversation with Sigma.

Paul2660 · 09-22-2016, 03:48 AM

Originally posted by AdrianM

Thanks, Paul. Can you confirm for me that you have the Crop Mode as "Auto" and the lens registers as full frame ? Just want to be clear if I have a conversation with Sigma.

Yes, crop mode is set to Auto.

Paul C

AdrianM · 09-22-2016, 03:57 AM

Originally posted by Paul2660

Yes, crop mode is set to Auto.

Paul C

Thanks Paul - just needed to check. That is interesting behaviour. I will have a chat with C.R.Kennedy in Melbourne some time.

Paul2660 · 09-22-2016, 05:40 AM

Just wanted to add that the 35 is an amazing optic.

Used it with Nikon tried to get Sigma to mount swap but it was to X pensive and they would not guarantee the swap.

One thing I sure miss is the 20. 1.4 Art and wish Sigma would add more lenses from the Art line up to Pentax. Hoping the new Samyang 20mm 1.8 will be a winner.

Paul C

ShiftR · 09-22-2016, 08:31 AM

Originally posted by Medex

why you need the dock for fixed focal lenght lens? You can make microadjustment in camera Menu.

You can make much finer focus adjustments over select distance ranges. The ability has proved useful on my 35A/K1 combo.

banep · 09-22-2016, 11:18 AM

Originally posted by AdrianM

Thanks Paul - just needed to check. That is interesting behaviour. I will have a chat with C.R.Kennedy in Melbourne some time.

Before that you two @Adrianm and @Paul2660 should compare lens id from exif of your files. There is possibility that those IDs are different which means different in lens firmware.
Other possibility could be a different K-1 firmware version.

puneet.gaur · 04-26-2017, 05:58 AM - **1 Like**

Sigma has released firmware for 35mm Art in all other mounts accept Pentax why is that so? Canon has firmware version 1.04 but for Pentax, it is still 1.00

puneet.gaur · 06-10-2021, 10:38 PM

https://imgur.com/PzeXPkF

09-21-2016, 03:09 AM - 1 Like	#1
AdrianM Pentaxian Join Date: Aug 2008 Location: Ipswich, Queensland, Australia Photos: Gallery \| Albums Posts: 589	Sigma 35 f1.4 DG Art on K-1 My newly acquired Sigma 35 Art has just arrived, but I noticed that on the K-1 it defaults to cropped sensor mode. While this can easily be fixed by forcing the camera to use Full Frame mode, I was wondering if there is a fix for this somewhere. So, hoping that another K-1 owner has already seen this and has an answer. ...and for info: I haven't got the USB dock (yet) but it would be great to know that it would solve the problem before I raced out to buy. Thanks in advance for your help.

09-21-2016, 03:13 AM - 1 Like	#2
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,609	Not that I know of, but Sigma has acknowledged the issue. Perhaps they'll release a firmware update to fix it at some point. 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:

09-21-2016, 08:09 AM	#5
banep Banned Join Date: Mar 2013 Posts: 360	Originally posted by AdrianM My newly acquired Sigma 35 Art has just arrived, but I noticed that on the K-1 it defaults to cropped sensor mode. While this can easily be fixed by forcing the camera to use Full Frame mode, I was wondering if there is a fix for this somewhere. So, hoping that another K-1 owner has already seen this and has an answer. . I have similar problem with some other Sigma autofocus full frame lenses on K-1. Looks like camera can't identify lens and activate crop mode by default. Or maybe it is the problem of brilliant Sigma reverse engineering. Firmware update is probably the only solution, lens needs another id. p.s. I'm pretty much pissed off on those Sigma K mount lenses. Some of them are not working (like 70-200), some of them have ID of my existing Pentax lenses and mess my micro focusing for those lenses, some of them are not recognized as full frame, local support is disaster, etc,etc... I think I'll sell them all and never buy Sigma again. Last edited by banep; 09-21-2016 at 12:35 PM.

06-10-2021, 10:38 PM	#14
puneet.gaur Junior Member Join Date: Feb 2016 Location: Ludhiana (India) Photos: Albums Posts: 35	No Support for Pentax mount lens https://imgur.com/PzeXPkF Last edited by puneet.gaur; 06-10-2021 at 10:49 PM.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Has anyone tried the Sigma Art 30 1.4 on Pentax K-1?	Belnan	Pentax K-1 & K-1 II	18	08-30-2019 01:20 PM
Sigma 50mm f1.4 (non Art) vs DA 55mm f1.4 for K-1	mandale	Pentax SLR Lens Discussion	17	07-17-2016 12:09 PM
Anyone tried the Sigma 35mm f1.4 Art on the K-3II?	schnitzer79	Pentax SLR Lens Discussion	13	05-17-2016 10:10 PM
For Sale - Sold: Pentax K-5 + Sigma 18-35 F1.8 HSM Art Lens	rexpoo	Sold Items	4	03-24-2016 04:12 PM
For Sale - Sold: Sigma 35 1.4 HSM Art	jayman_1975	Sold Items	6	06-22-2015 03:25 PM

09-21-2016, 05:02 AM	#3
Medex Pentaxian Join Date: May 2013 Location: Vilnius Posts: 1,023	Originally posted by AdrianM My newly acquired Sigma 35 Art has just arrived, but I noticed that on the K-1 it defaults to cropped sensor mode. While this can easily be fixed by forcing the camera to use Full Frame mode, I was wondering if there is a fix for this somewhere. So, hoping that another K-1 owner has already seen this and has an answer. ...and for info: I haven't got the USB dock (yet) but it would be great to know that it would solve the problem before I raced out to buy. Thanks in advance for your help. why you need the dock for fixed focal lenght lens? You can make microadjustment in camera Menu.

09-21-2016, 05:25 AM - 1 Like	#4
mee Veteran Member Join Date: May 2010 Posts: 7,403	Originally posted by Medex why you need the dock for fixed focal lenght lens? You can make microadjustment in camera Menu. His issue isn't front or back focusing but that the camera body senses the DG (Full Frame) lens as a DC (APS-C) on the K-1 Sigma sends lens firmwares through the dock.. in addition to micro adjustments.

09-21-2016, 07:01 PM	#6
Paul2660 Forum Member Join Date: Jun 2016 Posts: 67	I have the Sigma 35mm 1.4 and it works as it should, comes up in full frame mode. If possible you might see if you can exchange the lens for a different one. I have not updated the lens firmware since I purchased the lens 2 months ago. Looking forward to the Samyang 20mm 1.4 also, but guess it won't ship for a while yet. Paul C

09-22-2016, 02:17 AM	#7
AdrianM Pentaxian Join Date: Aug 2008 Location: Ipswich, Queensland, Australia Photos: Gallery \| Albums Posts: 589 Original Poster	Originally posted by Paul2660 I have the Sigma 35mm 1.4 and it works as it should, comes up in full frame mode. If possible you might see if you can exchange the lens for a different one. I have not updated the lens firmware since I purchased the lens 2 months ago. Looking forward to the Samyang 20mm 1.4 also, but guess it won't ship for a while yet. Paul C Thanks, Paul. Can you confirm for me that you have the Crop Mode as "Auto" and the lens registers as full frame ? Just want to be clear if I have a conversation with Sigma.

09-22-2016, 03:48 AM	#8
Paul2660 Forum Member Join Date: Jun 2016 Posts: 67	Originally posted by AdrianM Thanks, Paul. Can you confirm for me that you have the Crop Mode as "Auto" and the lens registers as full frame ? Just want to be clear if I have a conversation with Sigma. Yes, crop mode is set to Auto. Paul C

09-22-2016, 03:57 AM	#9
AdrianM Pentaxian Join Date: Aug 2008 Location: Ipswich, Queensland, Australia Photos: Gallery \| Albums Posts: 589 Original Poster	Originally posted by Paul2660 Yes, crop mode is set to Auto. Paul C Thanks Paul - just needed to check. That is interesting behaviour. I will have a chat with C.R.Kennedy in Melbourne some time.

09-22-2016, 05:40 AM	#10
Paul2660 Forum Member Join Date: Jun 2016 Posts: 67	Just wanted to add that the 35 is an amazing optic. Used it with Nikon tried to get Sigma to mount swap but it was to X pensive and they would not guarantee the swap. One thing I sure miss is the 20. 1.4 Art and wish Sigma would add more lenses from the Art line up to Pentax. Hoping the new Samyang 20mm 1.8 will be a winner. Paul C

09-22-2016, 08:31 AM	#11
ShiftR Forum Member Join Date: Aug 2010 Location: Virginia Posts: 62	Originally posted by Medex why you need the dock for fixed focal lenght lens? You can make microadjustment in camera Menu. You can make much finer focus adjustments over select distance ranges. The ability has proved useful on my 35A/K1 combo.

09-22-2016, 11:18 AM	#12
banep Banned Join Date: Mar 2013 Posts: 360	Originally posted by AdrianM Thanks Paul - just needed to check. That is interesting behaviour. I will have a chat with C.R.Kennedy in Melbourne some time. Before that you two @Adrianm and @Paul2660 should compare lens id from exif of your files. There is possibility that those IDs are different which means different in lens firmware. Other possibility could be a different K-1 firmware version.

04-26-2017, 05:58 AM - 1 Like	#13
puneet.gaur Junior Member Join Date: Feb 2016 Location: Ludhiana (India) Photos: Albums Posts: 35	Sigma has released firmware for 35mm Art in all other mounts accept Pentax why is that so? Canon has firmware version 1.04 but for Pentax, it is still 1.00

Sigma 35 f1.4 DG Art on K-1

Win a Pentax Limited Lens: Raffle Now Live!