645N lens adapter for K3

**bkpix** · 02-15-2014, 09:20 PM

I've got the Pentax k-mount/645 adapter and have used it with a P645 300/4 A* lens -- which is excellent. I have also used it with the 645 1.4x and 2x teleconverters. The whole thing is a bit clunky, though, as it's manual focus and stop-down metering.

BUT, with the 1.4x TC it's as sharp as the Canon 100-400L zoom lens is at 400.

JDelaware · 02-18-2014, 11:11 AM

K3 Arrived a few days ago, and all I can say is - I hate, HATE, hate the Pentax DA 18-55mm f/3.5-5.6 AL WR Zoom Lens, and if I had another lens right this second (the adapter is on its way so I can use my 645 lens' soon) I'd throw it of a moving car, back the car up and run over it again, pick up the pieces and throw them in a fire, remove it from the fire and stick in on my wall and call it art. But I can't because I have a shoot booked.

No matter what f/stop, lSO, lighting situation, tripod/no tripod, shutter speed, or combination of all of them - the photos are 'soft' (when I zoom in). Mostly at 18mm, better at 50mm, but am I on crack to think that a lens should be sharp, and no amount of softness is acceptable or am I being unreasonable?

RAART · 02-18-2014, 11:37 AM

I heard the rumors spreading that K-3 has some settings enabled that does not allow ultimate sharpness this camera is capable of. While I do plan to get this camera too a bit later in the year I was looking already into and read a lot of reviews and this came out, the sharpness issue. I think that one guy figured out what it is and it has to do with some settings there, unfortunately I do not remember which ones. If you have other Pentax why do not try this lens on the other camera and see if it is sharper than K-3. Just my 2c.

JDelaware · 02-18-2014, 11:50 AM

Originally posted by RAART

I heard the rumors spreading that K-3 has some settings enabled that does not allow ultimate sharpness this camera is capable of. While I do plan to get this camera too a bit later in the year I was looking already into and read a lot of reviews and this came out, the sharpness issue. I think that one guy figured out what it is and it has to do with some settings there, unfortunately I do not remember which ones. If you have other Pentax why do not try this lens on the other camera and see if it is sharper than K-3. Just my 2c.

The only lens' I have are for my 645, which I've just ordered the adapter for so when that comes in, I'll try them. I'm crossing my fingers!

RAART · 02-18-2014, 12:10 PM

Originally posted by JDelaware

The only lens' I have are for my 645, which I've just ordered the adapter for so when that comes in, I'll try them. I'm crossing my fingers!

I remembered what it was... Turn of the High ISO NR off on your K-3 and try then few shoots with kit lens and compare them.
Let me know of the results or if it is getting sharper for you. That might be one of the issue and of course if it does not change anything then it is the lens.

EDIT: What I meant in my previous message is if you have other DSLR Pentax camera not the lens...

JDelaware · 02-18-2014, 12:37 PM

Originally posted by RAART

I remembered what it was... Turn of the High ISO NR off on your K-3 and try then few shoots with kit lens and compare them.
Let me know of the results or if it is getting sharper for you. That might be one of the issue and of course if it does not change anything then it is the lens.

EDIT: What I meant in my previous message is if you have other DSLR Pentax camera not the lens...

Ahhh, I will have to check that out when I get home! Thanks Raart!
And sadly, no other Pentax DSLR's to play with.

JDelaware · 02-22-2014, 03:04 PM

The adapter has arrived, and while the 150mm 645 lens is pretty good (I'm still getting accustomed to manually focusing, and the images when enlarged are not as sharp as I want) my other 645 lens...Um I think is not going to work? It's a Pentax-FA 645 zoom 1:4.5 45-85mm and while the aperture ring and the zoom ring work great, the focus ring...not so much. It doesn't budge. Is it because it's hooked to an adapter and therefore cannot make 'digital' contact?

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Daedbird · 02-24-2014, 09:41 AM

If the new 645 shoots video, look for the 645 lens market to dry up fast

JDelaware · 02-24-2014, 02:54 PM

Originally posted by Daedbird

If the new 645 shoots video, look for the 645 lens market to dry up fast

Daedbird, I don't actually have a 645 digital camera (one day I'll be rich enough to get one though, just today isn't that day). I have a 645 N film camera and I'm using it's lens' on my new K3. The issue I'm having is the one of the lens' (Pentax-FA 645 zoom 1:4.5 45-85mm) I've hooked to the adapter isn't focusing because the focus ring isn't moveable.

Welfl · 05-05-2014, 04:02 PM

Originally posted by JDelaware

The issue I'm having is the one of the lens' (Pentax-FA 645 zoom 1:4.5 45-85mm) I've hooked to the adapter isn't focusing because the focus ring isn't moveable.

This is just a shot in the dark since I don't know what you do and don't know about your lens, or what you may have figured out since writing your last comment (the fact that no one else has suggested this makes me wonder if I am off base), but try this:

Hold your 45-85mm lens in front of you with its back end facing toward you. Pull the focus ring backward (toward the back end of the lens). If your lens is designed as I imagine it is, then it should move about one or two millimeters backward. It will make a relatively loud click as it locks into its new position. Once this is done, the focus ring should be in manual mode.

Let me know.

JDelaware · 05-05-2014, 04:17 PM

HOLY CRAP!!! YOU'RE A GENIUS!!! That worked perfect. I actually exclaimed when I saw it work! Thank you!!

Welfl · 05-05-2014, 05:24 PM

Originally posted by JDelaware

HOLY CRAP!!! YOU'RE A GENIUS!!! That worked perfect. I actually exclaimed when I saw it work! Thank you!!

You're welcome!

I'm very glad to have been of assistance.

Truth be told, I'm only a "genius" by accident, or partly by accident (tongue is in cheek as I write "genius"; ha). I originally thought the same thing that you did -- that there is no manual focus on my recently acquired FA 80-160mm 645 lens --; then I accidentally pulled the focus ring backward while it was mounted on my recently acquired Pentax 645N, and -- for some inexplicable reason -- my instincts immediately told me that it was now in manual-focus mode. That loud clicking may have helped my instincts. I think I pulled it backwards due to decades of habit, because I have a 1985-86 Focal (K-Mart) 80-200mm lens that zooms in and out by pulling and pushing the focus ring.

If possible, I really would like to see one or two of your K-3 / 45-85mm photos now that you can use them together. I'm still researching cheap third-party adapters, since I don't want to pay a fortune for an original Pentax adapter just to play around; but the idea of buying one via eBay doesn't appeal to me either. Thanks!

JDelaware · 05-05-2014, 06:29 PM

I will post them soon I promise.

I ended up getting my adapter ring on Ebay, from someone in Japan. It was a little scary because I wasn't sure if what he was selling, I actually needed. I also figured that it was less than an entire lens ($130), and if I didn't like it, I could just turn around and sell it.

JDelaware · 05-16-2014, 03:19 PM

Here's a practice shot with the Pentax-FA 645 zoom 1:4.5 45-85mm as promised. This takes LOTS of practice, of which I do need.
This little guy was caught by my dog, so I put him in a safe place to die. Or live, whichever happens first.

Welfl · 05-23-2014, 05:51 PM

Originally posted by JDelaware

Here's a practice shot with the Pentax-FA 645 zoom 1:4.5 45-85mm as promised. This takes LOTS of practice, of which I do need.
This little guy was caught by my dog, so I put him in a safe place to die. Or live, whichever happens first.

Thanks for sharing! Somehow I didn't see -- until now -- the notification that you had posted this comment (and photo).

What takes lots of practice? Balancing a large, heavy lens on a small camera, or doing manual focusing? Or both? I have a K-01, so I always use focus peaking with my vintage manual lenses. That part should be easy, but balancing my FA 645 80-160mm lens on the K-01 will be interesting. The lens is a lot larger and heavier than the camera, so I'm sure I will need to hold the lens as much or more than the camera, in part, so it won't (possibly) break the mount off of the camera. The FA 645 75mm lens isn't much larger than a 35mm lens, so it should be easy to use.

I'm still waiting patiently for a good deal for an adapter to pop up on Amazon, since I don't really want to have an eBay account.

Thank you again for posting the photo.

05-05-2014, 05:24 PM	#27
Welfl Senior Member Join Date: Jan 2012 Location: Nebraska Posts: 281	Originally posted by JDelaware HOLY CRAP!!! YOU'RE A GENIUS!!! That worked perfect. I actually exclaimed when I saw it work! Thank you!! You're welcome! I'm very glad to have been of assistance. Truth be told, I'm only a "genius" by accident, or partly by accident (tongue is in cheek as I write "genius"; ha). I originally thought the same thing that you did -- that there is no manual focus on my recently acquired FA 80-160mm 645 lens --; then I accidentally pulled the focus ring backward while it was mounted on my recently acquired Pentax 645N, and -- for some inexplicable reason -- my instincts immediately told me that it was now in manual-focus mode. That loud clicking may have helped my instincts. I think I pulled it backwards due to decades of habit, because I have a 1985-86 Focal (K-Mart) 80-200mm lens that zooms in and out by pulling and pushing the focus ring. If possible, I really would like to see one or two of your K-3 / 45-85mm photos now that you can use them together. I'm still researching cheap third-party adapters, since I don't want to pay a fortune for an original Pentax adapter just to play around; but the idea of buying one via eBay doesn't appeal to me either. Thanks! Last edited by Welfl; 05-05-2014 at 06:27 PM.

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02-15-2014, 09:20 PM	#16
bkpix Site Supporter Join Date: Feb 2010 Location: Creswell, Oregon Photos: Albums Posts: 568	I've got the Pentax k-mount/645 adapter and have used it with a P645 300/4 A* lens -- which is excellent. I have also used it with the 645 1.4x and 2x teleconverters. The whole thing is a bit clunky, though, as it's manual focus and stop-down metering. BUT, with the 1.4x TC it's as sharp as the Canon 100-400L zoom lens is at 400.

02-18-2014, 11:11 AM	#17
JDelaware New Member Join Date: Feb 2014 Posts: 19 Original Poster	K3 Arrived a few days ago, and all I can say is - I hate, HATE, hate the Pentax DA 18-55mm f/3.5-5.6 AL WR Zoom Lens, and if I had another lens right this second (the adapter is on its way so I can use my 645 lens' soon) I'd throw it of a moving car, back the car up and run over it again, pick up the pieces and throw them in a fire, remove it from the fire and stick in on my wall and call it art. But I can't because I have a shoot booked. No matter what f/stop, lSO, lighting situation, tripod/no tripod, shutter speed, or combination of all of them - the photos are 'soft' (when I zoom in). Mostly at 18mm, better at 50mm, but am I on crack to think that a lens should be sharp, and no amount of softness is acceptable or am I being unreasonable?

02-18-2014, 11:37 AM	#18
RAART Veteran Member Join Date: Apr 2013 Location: Oakville, ON Photos: Gallery Posts: 1,095	I heard the rumors spreading that K-3 has some settings enabled that does not allow ultimate sharpness this camera is capable of. While I do plan to get this camera too a bit later in the year I was looking already into and read a lot of reviews and this came out, the sharpness issue. I think that one guy figured out what it is and it has to do with some settings there, unfortunately I do not remember which ones. If you have other Pentax why do not try this lens on the other camera and see if it is sharper than K-3. Just my 2c.

02-18-2014, 11:50 AM	#19
JDelaware New Member Join Date: Feb 2014 Posts: 19 Original Poster	Originally posted by RAART I heard the rumors spreading that K-3 has some settings enabled that does not allow ultimate sharpness this camera is capable of. While I do plan to get this camera too a bit later in the year I was looking already into and read a lot of reviews and this came out, the sharpness issue. I think that one guy figured out what it is and it has to do with some settings there, unfortunately I do not remember which ones. If you have other Pentax why do not try this lens on the other camera and see if it is sharper than K-3. Just my 2c. The only lens' I have are for my 645, which I've just ordered the adapter for so when that comes in, I'll try them. I'm crossing my fingers!

02-18-2014, 12:10 PM	#20
RAART Veteran Member Join Date: Apr 2013 Location: Oakville, ON Photos: Gallery Posts: 1,095	Originally posted by JDelaware The only lens' I have are for my 645, which I've just ordered the adapter for so when that comes in, I'll try them. I'm crossing my fingers! I remembered what it was... Turn of the High ISO NR off on your K-3 and try then few shoots with kit lens and compare them. Let me know of the results or if it is getting sharper for you. That might be one of the issue and of course if it does not change anything then it is the lens. EDIT: What I meant in my previous message is if you have other DSLR Pentax camera not the lens...

02-18-2014, 12:37 PM	#21
JDelaware New Member Join Date: Feb 2014 Posts: 19 Original Poster	Originally posted by RAART I remembered what it was... Turn of the High ISO NR off on your K-3 and try then few shoots with kit lens and compare them. Let me know of the results or if it is getting sharper for you. That might be one of the issue and of course if it does not change anything then it is the lens. EDIT: What I meant in my previous message is if you have other DSLR Pentax camera not the lens... Ahhh, I will have to check that out when I get home! Thanks Raart! And sadly, no other Pentax DSLR's to play with.

02-24-2014, 09:41 AM	#23
Daedbird Senior Member Join Date: Sep 2009 Location: Wisconsin Posts: 156	If the new 645 shoots video, look for the 645 lens market to dry up fast

02-24-2014, 02:54 PM	#24
JDelaware New Member Join Date: Feb 2014 Posts: 19 Original Poster	Originally posted by Daedbird If the new 645 shoots video, look for the 645 lens market to dry up fast Daedbird, I don't actually have a 645 digital camera (one day I'll be rich enough to get one though, just today isn't that day). I have a 645 N film camera and I'm using it's lens' on my new K3. The issue I'm having is the one of the lens' (Pentax-FA 645 zoom 1:4.5 45-85mm) I've hooked to the adapter isn't focusing because the focus ring isn't moveable.

05-05-2014, 04:02 PM	#25
Welfl Senior Member Join Date: Jan 2012 Location: Nebraska Posts: 281	Originally posted by JDelaware The issue I'm having is the one of the lens' (Pentax-FA 645 zoom 1:4.5 45-85mm) I've hooked to the adapter isn't focusing because the focus ring isn't moveable. This is just a shot in the dark since I don't know what you do and don't know about your lens, or what you may have figured out since writing your last comment (the fact that no one else has suggested this makes me wonder if I am off base), but try this: Hold your 45-85mm lens in front of you with its back end facing toward you. Pull the focus ring backward (toward the back end of the lens). If your lens is designed as I imagine it is, then it should move about one or two millimeters backward. It will make a relatively loud click as it locks into its new position. Once this is done, the focus ring should be in manual mode. Let me know.

05-05-2014, 04:17 PM	#26
JDelaware New Member Join Date: Feb 2014 Posts: 19 Original Poster	HOLY CRAP!!! YOU'RE A GENIUS!!! That worked perfect. I actually exclaimed when I saw it work! Thank you!!

05-05-2014, 06:29 PM	#28
JDelaware New Member Join Date: Feb 2014 Posts: 19 Original Poster	I will post them soon I promise. I ended up getting my adapter ring on Ebay, from someone in Japan. It was a little scary because I wasn't sure if what he was selling, I actually needed. I also figured that it was less than an entire lens ($130), and if I didn't like it, I could just turn around and sell it.

05-23-2014, 05:51 PM	#30
Welfl Senior Member Join Date: Jan 2012 Location: Nebraska Posts: 281	Originally posted by JDelaware Here's a practice shot with the Pentax-FA 645 zoom 1:4.5 45-85mm as promised. This takes LOTS of practice, of which I do need. This little guy was caught by my dog, so I put him in a safe place to die. Or live, whichever happens first. Thanks for sharing! Somehow I didn't see -- until now -- the notification that you had posted this comment (and photo). What takes lots of practice? Balancing a large, heavy lens on a small camera, or doing manual focusing? Or both? I have a K-01, so I always use focus peaking with my vintage manual lenses. That part should be easy, but balancing my FA 645 80-160mm lens on the K-01 will be interesting. The lens is a lot larger and heavier than the camera, so I'm sure I will need to hold the lens as much or more than the camera, in part, so it won't (possibly) break the mount off of the camera. The FA 645 75mm lens isn't much larger than a 35mm lens, so it should be easy to use. I'm still waiting patiently for a good deal for an adapter to pop up on Amazon, since I don't really want to have an eBay account. Thank you again for posting the photo.