[Geodude]

Exactly.

Expanding on the question, I often use an SMC Pentax-A 1:4 70-210mm manual lens on my K-3. I always set the focal length at 70mm as mostly I use the lens for macro shots, but I do make use of the zoom. So, if I'm going to use the zoom at 150mm, should I reset it at that value, or does it not matter? Mostly, my concern is for sharpness of the image.

[mikesbike]

For practical use purposes, you got it right in your 50mm = 75mm on a FF body equation.

You can go into all the why's, differences, etc. but this is what it boils down to. With a FF body, and getting closer to get the same framing, DOF and perspective will change. Or, more accurately, to take the shot from the same distance using a FF body, and cropping afterwards in post process using editing software to get the same framing, then you are throwing out a lot of pixels, so you'll likely wind up with the same pixel density or less than that of the same shot with your K-5. There are pros and cons to everything. But the K-5 has a fine reputation for very fine IQ, and very good low-light, higher ISO performance. So you have a fine tool in your new camera that can serve you well for years. Just using the 1.5x formula to compute the FL results you will get from a lens compared to what it would do on your K1000 will be fine. Actually, for Pentax I believe it is 1.53x.

I suggest tweeking your settings in your Custom Image menus. First, have your mode dial set to the "P" mode. With the K-5, these are accessed via the button just to the right of the ok button. Now the 4 buttons surrounding the ok button can be used for navigation and for changes. The default "Bright" category should come up right away. If not, just use the right or left buttons to navigate to the "Bright" category. Then scroll down to the bottom, Sharpening selections, and you should see the default setting is up one to +1. I increased mine up one more to +2. With this camera, that works well. Then I used my thumb dial to put an "F" by the "S" for Fine Sharpening. This setting will provide finer detail in your images. If you go back up to the very top, you can navigate over one, to the "Natural" category, and set sharpening to the same settings as in the"Bright" category. Then go back to the top and put the camera back to the "Bright" category, which is best for most shooting, and hit the ok button.

---------- Post added 08-12-18 at 01:10 PM ----------

Expanding on the question, I often use an SMC Pentax-A 1:4 70-210mm manual lens on my K-3. I always set the focal length at 70mm as mostly I use the lens for macro shots, but I do make use of the zoom. So, if I'm going to use the zoom at 150mm, should I reset it at that value, or does it not matter? Mostly, my concern is for sharpness of the image.

I would imagine you set the FL to that you will be using, for the sake of the SR. But with an "A" lens I wonder if that is necessary, since the lens already has info contacts to the body.

[UncleVanya]

I would imagine you set the FL to that you will be using, for the sake of the SR. But with an "A" lens I wonder if that is necessary, since the lens already has info contacts to the body.

True A series lenses (not modern Samyangs) don't have the data pin. The only info is passive and essentially tells the camera the maximum aperture value. Nothing about focal length is conveyed.

[clickclick]

So, if I'm going to use the zoom at 150mm, should I reset it at that value, or does it not matter? Mostly, my concern is for sharpness of the image.

Yes, for best results, resetting to 150 is correct. The camera is using this information to fine tune the shake reduction (SR). You can either go through the menu setup or just cycle the power on the camera (probably faster).

[mikesbike]

True A series lenses (not modern Samyangs) don't have the data pin. The only info is passive and essentially tells the camera the maximum aperture value. Nothing about focal length is conveyed.

Hmmm. This means a tele zoom lens, or maybe a tele prime lens of the "A" type, would not do well for shooting in Program mode, or Av. Program mode is usually designed so as FL is increased, the program adjusts for a faster shutter speed.

I do not have any "A" lenses. My MF lenses are of the "M" type. I do have a Super Program body, which originally used the "A" type lenses, but maybe Program operation back then was more primitive. I have not tried using an AF tele zoom lens with it- just old "M" lenses.

[reh321]

I'm assuming this is only to tell the camera how to use it's image stabilization motors and whatnot, right?

Right.

The camera already "knows" it has a crop sensor, and already takes that into account when setting up its stabilization.

[UncleVanya]

Hmmm. This means a tele zoom lens, or maybe a tele prime lens of the "A" type, would not do well for shooting in Program mode, or Av. Program mode is usually designed so as FL is increased, the program adjusts for a faster shutter speed.

I do not have any "A" lenses. My MF lenses are of the "M" type. I do have a Super Program body, which originally used the "A" type lenses, but maybe Program operation back then was more primitive. I have not tried using an AF tele zoom lens with it- just old "M" lenses.

This should help. The Evolution of the Pentax K-mount - Articles and Tips | PentaxForums.com

[disconnekt]

Hello!

I just got my K-5 yesterday and have been messing around with it.
All of my lenses are manual, so I have to input the focal length of the lens when I boot the camera up.

Should I account for crop factor when I give it an input?
All of my lenses are full-frame from my K1000.

So, if I put my 50mm lens on my K-5, should I tell it that the focal length is 50mm or 75mm?

I'm assuming this is only to tell the camera how to use it's image stabilization motors and whatnot, right?

In a word: no.
A 50mm is a 50mm, no matter what format you're using, the only difference is the field of view when adapting a larger format to a smaller one.

[Geodude]

Thanks to all who provided input to my question about the Pentax-A 1:4 70-210mm and FL setting. I only use it in M mode, so I won't run into problems using the P or Av modes. And, as per some advice, if I use the tele-zoom rather than the macro setting, I'll reset the FL to whatever mm I've adjusted the zoom aspect to. It might actually be better to simply disengage the SR and not be bothered with possible quirks, except shaky hands...

[UncleVanya]

Thanks to all who provided input to my question about the Pentax-A 1:4 70-210mm and FL setting. I only use it in M mode, so I won't run into problems using the P or Av modes. And, as per some advice, if I use the tele-zoom rather than the macro setting, I'll reset the FL to whatever mm I've adjusted the zoom aspect to. It might actually be better to simply disengage the SR and not be bothered with possible quirks, except shaky hands...

The best advice I have seen for lenses that do not supply focal length to the camera is to set to either:

1. The exact zoom setting you are using if you are willing to keep resetting it.
2. The shortest it can go.

In theory option 2 will never OVER correct so at worst you get some benefit but not as much as option 1 provides.

[mikesbike]

Thanks to all who provided input to my question about the Pentax-A 1:4 70-210mm and FL setting. I only use it in M mode, so I won't run into problems using the P or Av modes. And, as per some advice, if I use the tele-zoom rather than the macro setting, I'll reset the FL to whatever mm I've adjusted the zoom aspect to. It might actually be better to simply disengage the SR and not be bothered with possible quirks, except shaky hands...

Especially when using a lens like a 70-200mm, you are invariably better off to have some degree of SR for hand-held shooting.

[BirdDude007]

Congrats on the K5, I too, have one as well. It was demoted to backup body when I bought my K3, but after about two weeks it has clambered right back up to level playing ground with the K3, I still really love the IQ of this body regardless the AF shortcomings compared to the K3. Aas for the A lenses, I mostly use A lenses or newer, I am not wild about having to constantly stoping down the manual lenses, however I will have no problem doing so.
I have used the A lenses in all modes of the K5 without any exposure issues.
You will really enjoy using this stellar camera .....the K5

[Ropuchy]

Congrats on the K5, I too, have one as well. It was demoted to backup body when I bought my K3, but after about two weeks it has clambered right back up to level playing ground with the K3, I still really love the IQ of this body regardless the AF shortcomings compared to the K3. Aas for the A lenses, I mostly use A lenses or newer, I am not wild about having to constantly stoping down the manual lenses, however I will have no problem doing so.
I have used the A lenses in all modes of the K5 without any exposure issues.
You will really enjoy using this stellar camera .....the K5

Yeah, I've heard really good things about the K-5! Glad I got it.
I don't use AF, so it's not much of a shortcoming for me

Thanks! You have fun with your K-3 as well!