[SkipperRi]

Hi to all,
I bought Pentax K-7 and I have one Cosina (75-210) lenses. So, I'm inexperienced with Pentax cameras and settings for now. Which is the best setting for macro shooting with this lens? On start, should I put 75 or 200 (there is no 210) value for focal focus? And, how can I get sharp pictures of macro?

Thanks in advance!

[calsan]

Hi skipperri
According to this (support article for the kx) on Pentax's website, you choose a focal length close to the midpoint of the zoom range. Doesn't have to be exact to the mm, just go for the nearest number.

Using Older Lenses with the PENTAX K-x | Pentax Support
Strangely, the same support article for the K7 doesn't mention old zoom lenses.


Best way to get sharp images in macro is with a tripod! The next best way is to make sure you use a pretty high shutter speed to compensate for hand movement. Experiment and see how you go, each person is different. Some people have hands like a surgeon, most don't. You may need to bump up your ISO level, but it's best to try and get more light in the shot.

[rbefly]

Hello SkipperRI, Welcome to the Forum!
The input for manual lenses does two things, as far as I know- It sets the shake reduction for the lens focal length and provides EXIF date so you can look up photos based upon which lens you used. This is very handy, so you might want to put in a number that won't (likely) be used in the future, like 150mm. If, for example, you input 100mm, sometime down the road you might buy one of the many 100mm Pentax prime lenses and there would be confusion.
Shooting Macro is a whole world in itself. There are new and different skills that aren't common to most other types of photography, although once you start mastering Macro, some of these skills and techniques will make you a better overall photographer.
First and foremost, understanding focus points and depth of field (DOF). DOF is the area in a photo that is considered to be in sharp focus, all other points (both closer and further from the camera position) are out-of-focus (OOF) to a greater or lesser degree. This is much easier to see in sample photos than to explain.
When you close-focus, that is, shoot while very near to the subject, your DOF is razor-thin, we're talking mm. If you focus on the front petal of a flower, another petal 5mm back (further away) will be OOF. The entire background will be a fuzzy, shapeless blob. This character, the type of background blur is called 'Bokeh', and 'good' Bokeh is prized by Macro and other types of photography fans.
How 'deep" or long the DOF is, is determined by the aperture or f-stop. Using the lens wide-open (the lowest f-number) results in the thinnest or most shallow DOF. Stopping down to f/22, for example, yields much more DOF. The tradeoff here is that you're letting much less light into the lens at f/22, so your shutter speed will be longer. And remember, at typical Macro focusing distances, 'much greater DOF' might be 1/2 inch!
So, while this is a lot of info at the start, you can still create good Macro photos by following the general guidelines; Use a tripod and remote shutter release. Shoot in Av mode. Manual focus slowly, carefully and be sure the focus point you finally select is the central point of interest in the scene. Take several shots of the same scene with different shutter speed/f-stop combinations (Bracket) so you will have a selection to choose from. This is where the EXIF data will be a great help. On your PC monitor you'll clearly see that one f/stop/shutter speed combo works better than others for that particular scene, and this greatly increases the speed of learning.
Sorry I rambled on so long, but this is a very complex subject. Read all the Macro posts and study the photos, notice the gear and settings used.
Good Luck!
Ron

[SkipperRi]

Hi skipperri
According to this (support article for the kx) on Pentax's website, you choose a focal length close to the midpoint of the zoom range. Doesn't have to be exact to the mm, just go for the nearest number.

Using Older Lenses with the PENTAX K-x | Pentax Support
Strangely, the same support article for the K7 doesn't mention old zoom lenses.


Best way to get sharp images in macro is with a tripod! The next best way is to make sure you use a pretty high shutter speed to compensate for hand movement. Experiment and see how you go, each person is different. Some people have hands like a surgeon, most don't. You may need to bump up your ISO level, but it's best to try and get more light in the shot.

Thank you for your answer!

Hello SkipperRI, Welcome to the Forum!
The input for manual lenses does two things, as far as I know- It sets the shake reduction for the lens focal length and provides EXIF date so you can look up photos based upon which lens you used. This is very handy, so you might want to put in a number that won't (likely) be used in the future, like 150mm. If, for example, you input 100mm, sometime down the road you might buy one of the many 100mm Pentax prime lenses and there would be confusion.
Shooting Macro is a whole world in itself. There are new and different skills that aren't common to most other types of photography, although once you start mastering Macro, some of these skills and techniques will make you a better overall photographer.
First and foremost, understanding focus points and depth of field (DOF). DOF is the area in a photo that is considered to be in sharp focus, all other points (both closer and further from the camera position) are out-of-focus (OOF) to a greater or lesser degree. This is much easier to see in sample photos than to explain.
When you close-focus, that is, shoot while very near to the subject, your DOF is razor-thin, we're talking mm. If you focus on the front petal of a flower, another petal 5mm back (further away) will be OOF. The entire background will be a fuzzy, shapeless blob. This character, the type of background blur is called 'Bokeh', and 'good' Bokeh is prized by Macro and other types of photography fans.
How 'deep" or long the DOF is, is determined by the aperture or f-stop. Using the lens wide-open (the lowest f-number) results in the thinnest or most shallow DOF. Stopping down to f/22, for example, yields much more DOF. The tradeoff here is that you're letting much less light into the lens at f/22, so your shutter speed will be longer. And remember, at typical Macro focusing distances, 'much greater DOF' might be 1/2 inch!
So, while this is a lot of info at the start, you can still create good Macro photos by following the general guidelines; Use a tripod and remote shutter release. Shoot in Av mode. Manual focus slowly, carefully and be sure the focus point you finally select is the central point of interest in the scene. Take several shots of the same scene with different shutter speed/f-stop combinations (Bracket) so you will have a selection to choose from. This is where the EXIF data will be a great help. On your PC monitor you'll clearly see that one f/stop/shutter speed combo works better than others for that particular scene, and this greatly increases the speed of learning.
Sorry I rambled on so long, but this is a very complex subject. Read all the Macro posts and study the photos, notice the gear and settings used.
Good Luck!
Ron

Ron,

Thank you so much! Don't apologize for long post. Your information are priceless!