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01-04-2011, 03:42 PM   #1
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New K-r owner with some lenses

Hello everybody.
I recently got my hands on a White K-R and am excited to dive into photography.
I also got my hands on some old supposedly 'Pentax' lenses. I was excited to learn that new Pentax bodies are backwards compatible lenses and couldn't wait to try them out. I, of course, got a lens stuck on the body and had to use a cell phone screen protector and a razor blade to get it off. That is when I read up on the different mounting types, and got to work modifying the lenses. I used an eyeglasses screwdriver to open them up and remove the pins.

So here are the lenses I have. I'm interested to hear your opinions on them.


This is a Cosina (Vivitar) 28mm 1:2.8f 49mm
It is a PK-A/R mount. I have removed the offending pin.


Next is an Albinar ADG 75-300mm 1:5.6f 55mm
It is a KR mount. I have removed the offending pin after getting it stuck to the K-r body.


Finally is a Cimko MT Series 80-200mm 1:4.5f 52mm


I will probably be shooting lots of scenery, cars and motorcycle photos and look forward to learning from all of you here.

01-05-2011, 06:46 AM   #2
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Welcome aboard!

I haven't used any of those lenses but I'm guessing that the Vivitar 28mm is going to be at least an "OK" lens. Vivitar is a brand which lenses were made by many different manufacturers, and their quality ranges from excellent to crappy. There's a long discussion about different Vivitar 28mm versions in the Lens section. And member rparmar (the starter of the aforementioned thread) has also made website listing all the variations so far: The Great Vivitar Bestiary.

Those older zooms are often not that good but you never know until you try them out. I think Albinar is a store brand made by someone else but Cimko is an actual manufacturer.

As this thread is more about lenses than the K-r (great camera btw) I'd suggest this thread to be moved to the Pentax slr Lens Discussion. Where I think more people would see it and maybe someone with experience with these lenses would chime in.
01-11-2011, 06:37 AM   #3
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Hi ajw85
I do not know about those lenses in your hands. But I got similar experience. I have a Tokina SD 70-210 lens from 70’s I believe. It is very old. I use it in my brand new Pentax k-r.
In order to use it some necessary settings are as follows.
1) Set internal focal length. Because it is an old lens that is used with 35mm cameras, we should set internal focal length to the value of used lens focal length multiplied by 1.5. For this lens I set it up to 300 (Approximately 210 X 1.5). This setting is activated automatically, when you attached the lens into the k-r first time power on.
2) Use manual focus (MF) instead of AF.
3) For the old lens it is better to set aperture settings to “permitted” from the custom menu page 4, Option 22. Otherwise you should set the aperture ring to “A” on the lens. Other options don’t work with the k-r using old lens. You have error notification when you turn on your camera.
I hope it helps you how to use old lens with k-r. Have nice shots.
01-11-2011, 08:04 AM   #4
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QuoteOriginally posted by Navajo Quote
1) Set internal focal length. Because it is an old lens that is used with 35mm cameras, we should set internal focal length to the value of used lens focal length multiplied by 1.5. For this lens I set it up to 300 (Approximately 210 X 1.5). This setting is activated automatically, when you attached the lens into the k-r first time power on.
AFAIK this is wrong. The focal length setting should be what it says on the lens. Setting too big a value can lead to blurring because the SR system can overcompensate for the camera shake. Of course with a zoom it's quite a hassle to change it every time you zoom in or out so I just enter one value in between the min and max focal lengths. For my favourite 28-90mm lens I've lately used 40mm as the SR setting with good results.

01-12-2011, 10:59 PM   #5
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Hi Ovim,
I understand why you set it between the min and max values of the lens. But for the old 35mm SLR camera lenses we should multiply it by 1,5 shouldn't we? That was what I read in the user manual. Or based on your experience to leave it as the lens value.
According to your suggestions I should set SR to (210-70)/2*1,5 that makes 105. Is that what you suggest? Thanks.
01-12-2011, 11:29 PM   #6
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QuoteOriginally posted by Navajo Quote
Hi Ovim,
I understand why you set it between the min and max values of the lens. But for the old 35mm SLR camera lenses we should multiply it by 1,5 shouldn't we? That was what I read in the user manual. Or based on your experience to leave it as the lens value.
I only have the Finnish Manual at hand so I'm not going to quote it here but it only says you should input the nearest value to the focal length of your lens.

I think you've mixing the field of view (FOV) into this. Focal length doesn't change. A 50mm lens is a 50mm lens no matter if it's a old M42/K/M/A/F/FA-lens or a new DA (digital only). And they produce the exactly same picture on your K-r.

x1.5 crop factor comes from the fact that Pentax DSLRs have smaller sensor than the 35mm film was so the field of view is different e.g 50mm lens on a dslr produces the same FOV as a 75mm lens on film but this doesn't change the focal length of the lens.

Last edited by ovim; 01-13-2011 at 01:39 AM.
01-13-2011, 01:38 AM   #7
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QuoteOriginally posted by Navajo Quote
According to your suggestions I should set SR to (210-70)/2*1,5 that makes 105. Is that what you suggest? Thanks.
Actually I was following the suggestion from this thread: What focal length for a manual zoom?

I'm not sure if I understood what m42man meant there but I've seen no ill effects by using this approach.
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