K1 and lenses

SherylT · 07-11-2017, 05:58 AM

I am thinking of moving from the K7 to a K1 but can't seem to clarify if my existing lenses will work properly on the K1. Has anyone had any experience with this?

**RobA_Oz** · 07-11-2017, 06:03 AM

Hi, Sheryl and welcome to Pentax Forums. All of your lenses will fit the K-1 but if any of them are specifically made for an APS-C sensor, such as the K7 has, then they may cause vignetting of the image on the K-1. There's a list of K-mount lenses here in the Forum, showing whether they vignette or not.

ronniemac · 07-11-2017, 06:06 AM

All Pentax lenses work properly on K-1. Quite a few are FF, the rest work in corp mode if you want. Usually its best to take in FF mode and crop afterwards - you will most often get a larger than aps-c frame. You can check for most lenses on K-1 by going to PENTAX K-1 Laboratory | PENTAX K-1 Special site | RICOH IMAGING

Sandy Hancock · 07-11-2017, 06:07 AM

^What they said
Which lenses do you have?

D1N0 · 07-11-2017, 06:13 AM

Most DA zoom lenses will vignette for at least part of the zoom range. Any prime lens from 35mm up will cover full frame. If you have old film era lenses, they will all work on the K-1. If you have third party lenses the same is probably applicable especially for zooms that start at wide angles (16 to 18mm). Some sigma lenses (documented) have a small problem fitting under de pentaprism protrusion causing scratches and or poor/non operation. Just tell us which lenses you have.

DeadJohn · 07-11-2017, 09:58 AM

Originally posted by SherylT

I am thinking of moving from the K7 to a K1 but can't seem to clarify if my existing lenses will work properly on the K1. Has anyone had any experience with this?

All Pentax lenses will work with the K-1. If you have 3rd party lenses, most will work, but a few Sigma autofocus lenses might have compatibility issues.

Plan to be confused by talk of crop vs full-frame. The K-1 has a larger sensor than the K-7. Some lenses might not project a large enough image to fully use the corners of the K-1, but camera settings or PC software can clip off the dim corners if necessary.

Even if you work in crop mode, the K-1 will give you vast improvements over the K-7. Faster and more reliable autofocus. Better low light performance. Sharper images due to no AA filter. Improve shake reduction. And a whole bunch of convenience features like the 3rd control wheel, GPS, tiltable LCD, wifi.

**BigDave** · 07-11-2017, 10:50 AM

I switched from the K-7 to the K-1 and have never regretted the decision. I do need a more powerful PC now to handle the larger file sizes!

I have a host of lenses, but I planned on Pentax coming out with a full frame eventually (I waited 5 years, but I know others waited much longer!). The lenses I purchased were mostly FF lenses.

That said, any a, a*, M or older K lens is full frame and works fine on the K-1. Pentax FA and FA* lenses are FF. Any Sigma DG lens is FF and any Tamron Di lens is FF (not Di ii, which are APS-C lenses and Di iii, for mirrorless cameras).

Even if you have a Pentax DA or other lens designed for APS-C cameras (K-7) it can still be used with the K-1 as you can shoot in Crop mode (in which the camera switches automatically to APS-C mode) or as I do, I just leave the camera in FF mode and crop later when editing. The crop mode of the K-1 has the same image sensor resolution as the K-5 would, still making it better than the K-7. I use a Sigma 10-20mm f3.5 lens, bought for my K-7, on my K-1 quite effectively, but know that the lens starts to vignette at about 14mm. Up to that point I have a nice 14-20mm wide angle zoom!

And as an added benefit for getting the K-1, the batteries are the same as your K-7! Switch and don't look back!

Wheatfield · 07-11-2017, 02:50 PM

Originally posted by SherylT

I am thinking of moving from the K7 to a K1 but can't seem to clarify if my existing lenses will work properly on the K1. Has anyone had any experience with this?

Define "properly"? They will all "work properly", presuming they "work properly" on your K7, but they may not cover the full K1 frame size. This doesn't mean they aren't "working properly", only that they have some design limitations.
If your lenses are all designed for the smaller format, you would be better off buying a K3-2 unless you want to buy new glass.

07-11-2017, 05:58 AM	#1
SherylT New Member Join Date: Jul 2017 Posts: 1	K1 and lenses I am thinking of moving from the K7 to a K1 but can't seem to clarify if my existing lenses will work properly on the K1. Has anyone had any experience with this?

07-11-2017, 06:03 AM	#2
RobA_Oz Site Supporter Join Date: Nov 2008 Location: Tasmania, Australia Photos: Gallery Posts: 8,209	Hi, Sheryl and welcome to Pentax Forums. All of your lenses will fit the K-1 but if any of them are specifically made for an APS-C sensor, such as the K7 has, then they may cause vignetting of the image on the K-1. There's a list of K-mount lenses here in the Forum, showing whether they vignette or not. Last edited by RobA_Oz; 07-11-2017 at 06:14 AM.

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07-11-2017, 06:06 AM	#3
ronniemac Senior Member Join Date: Apr 2011 Location: Oxford Photos: Albums Posts: 244	All Pentax lenses work properly on K-1. Quite a few are FF, the rest work in corp mode if you want. Usually its best to take in FF mode and crop afterwards - you will most often get a larger than aps-c frame. You can check for most lenses on K-1 by going to PENTAX K-1 Laboratory \| PENTAX K-1 Special site \| RICOH IMAGING

07-11-2017, 06:07 AM	#4
Sandy Hancock Moderator Site Supporter Join Date: Feb 2012 Location: Adelaide Hills, South Australia Photos: Gallery \| Albums Posts: 11,275	^What they said Which lenses do you have?

07-11-2017, 06:13 AM	#5
D1N0 Pentaxian Join Date: May 2012 Location: --- Photos: Gallery Posts: 6,802	Most DA zoom lenses will vignette for at least part of the zoom range. Any prime lens from 35mm up will cover full frame. If you have old film era lenses, they will all work on the K-1. If you have third party lenses the same is probably applicable especially for zooms that start at wide angles (16 to 18mm). Some sigma lenses (documented) have a small problem fitting under de pentaprism protrusion causing scratches and or poor/non operation. Just tell us which lenses you have.

07-11-2017, 09:58 AM	#6
DeadJohn Pentaxian Join Date: Jan 2011 Location: New York Posts: 4,834	Originally posted by SherylT I am thinking of moving from the K7 to a K1 but can't seem to clarify if my existing lenses will work properly on the K1. Has anyone had any experience with this? All Pentax lenses will work with the K-1. If you have 3rd party lenses, most will work, but a few Sigma autofocus lenses might have compatibility issues. Plan to be confused by talk of crop vs full-frame. The K-1 has a larger sensor than the K-7. Some lenses might not project a large enough image to fully use the corners of the K-1, but camera settings or PC software can clip off the dim corners if necessary. Even if you work in crop mode, the K-1 will give you vast improvements over the K-7. Faster and more reliable autofocus. Better low light performance. Sharper images due to no AA filter. Improve shake reduction. And a whole bunch of convenience features like the 3rd control wheel, GPS, tiltable LCD, wifi.

07-11-2017, 10:50 AM	#7
BigDave Site Supporter Join Date: Sep 2010 Location: Hudson Valley, NY Photos: Gallery \| Albums Posts: 2,626	I switched from the K-7 to the K-1 and have never regretted the decision. I do need a more powerful PC now to handle the larger file sizes! I have a host of lenses, but I planned on Pentax coming out with a full frame eventually (I waited 5 years, but I know others waited much longer!). The lenses I purchased were mostly FF lenses. That said, any a, a, M or older K lens is full frame and works fine on the K-1. Pentax FA and FA lenses are FF. Any Sigma DG lens is FF and any Tamron Di lens is FF (not Di ii, which are APS-C lenses and Di iii, for mirrorless cameras). Even if you have a Pentax DA or other lens designed for APS-C cameras (K-7) it can still be used with the K-1 as you can shoot in Crop mode (in which the camera switches automatically to APS-C mode) or as I do, I just leave the camera in FF mode and crop later when editing. The crop mode of the K-1 has the same image sensor resolution as the K-5 would, still making it better than the K-7. I use a Sigma 10-20mm f3.5 lens, bought for my K-7, on my K-1 quite effectively, but know that the lens starts to vignette at about 14mm. Up to that point I have a nice 14-20mm wide angle zoom! And as an added benefit for getting the K-1, the batteries are the same as your K-7! Switch and don't look back!

07-11-2017, 02:50 PM	#8
Wheatfield Moderator Join Date: Apr 2008 Location: The wheatfields of Canada Posts: 15,986	Originally posted by SherylT I am thinking of moving from the K7 to a K1 but can't seem to clarify if my existing lenses will work properly on the K1. Has anyone had any experience with this? Define "properly"? They will all "work properly", presuming they "work properly" on your K7, but they may not cover the full K1 frame size. This doesn't mean they aren't "working properly", only that they have some design limitations. If your lenses are all designed for the smaller format, you would be better off buying a K3-2 unless you want to buy new glass.