Portraits

What would be the best lens for the K10D to take Portraits.

I have heard a 50mm Macro is good
also 70 and 77 mm F1.4 or F2.8

Am I on the right track.

Thanks

Peter

In 35mm terms the ideal portrait lens is around 85-100mm. The perspective is good, the photographer doesn't crowd the subject and yet is close enough to communicate properly.

So in terms of digital a 50mm focal length or thereabouts works very well.

This makes even the kit 18-55mm lens perfectly useable for portraits. The 50-200mm also is fine. I've even used the 16-45mm with good success. The 50mm f1.4 also is excellent.

You don't need to worry too much which one you choose as the 1.5x crop factor brings all these lenses into the mix for consideration.

There's no real need for a macro lens for this either as you will not be getting that close. A macro will be a bit cruel on skin texture as well.

in addition, it helps to know what you like in a portrait.
I use the m 50mm 1.4, the 85 soft focus, and various others including the 50mm macro.
in general, longer focal lengths for big noses, wider apertures for shallow dof, all the usual tips.
my belief is that ALL modern lenses are too sharp for most portrait work.
so which ever lens you go with (ie kit lenses JR already mentioned) consider adding some diffusion (filters, pre or post), and use the widest aperture possible.
I do consider the 50mm macro 2.8, in combination with my ds2 (compatibility with older flashes) my af 080c ringflash to be an outstanding portrait lens.
I'm hoping for the 70 for xmas.

My thanks to all for the expert advice.

I wll go for the 50mm F1.4 I think

Lets see what happens

peter

A wise choice. When you want a change, the 77mm Ltd is the world's best portrait lens (ducks missiles hurled by 85mm f1.4 lovers).

G

Even the digital lenses have the crop factor? I figured if they produce a lens for a digital body they would just make it compatible with the sensor size?

Digital lenses are designed to cover the area of the CCD, a smaller image circle than the 35mm frame would require. They also have a more telecentric design - that is, the light rays exiting the rear element of the lens are as parallel as possible.

The "crop factor" is a way of expressing what happens to the field of view. A 50mm lens will, for example, always be a 50mm lens, regardless of what format it is used on. However, compared to 35mm film format, only the centre of the field is used on a DSLR. This is equivalent to cropping the full frame image and the effect is as though it were a 75mm lens on 35mm format. This is the 1.5x "crop factor". If you think about this, it may have the field of view of a film camera's 75mm lens and hence be suitable for portraiture, but also it still has the depth of field on a 50mm lens.

This latter point has been argued to extinction on this and other forums, but in practical terms this means more DOF on smaller formats for a given field of view and less DOF on larger formats.

This is well borne out by the extremes, where a standard lens on Minox sub-min cameras is 15mm and has immense DOF and on say a large format camera 210mm with very little DOF.

You might want to consider the older Pentax F SMC 50mm 1.7 I have this and this lens is stunning for the money I paid.

Pete

a strange setup theyve chosen. i grasp the fact that it does extend FOV but why did they design it this way? just to be able to use all the previous lenses. again sorry to beat a dead horse, ive actually read many of these kinds of threads so if you just point me to a site that may have more information than your willing to write it would be appreciated. thanks.

Pentax didn't design it that way, the laws of optics did.

If you could be more specific about what you need to know we'd be happy to try to provide the answer.

What is the bit of information that needs greater detail?

yes the sensor is smaller than the actual 24x36mm frame so this means that they are only using a portion of coverage of the actual lens? but there are full frame dslrs with no crop factor though as well. so therefore a bigger sensor in say the k10 would be more money or something?

basically they call it a 1.5x simply in comparison to a full frame 35mm film camera. but in actuality isnt the coverage of a digital lens the entirety of the sensor?

Only a portion of the coverage of a lens that is designed for 35mm cameras is used. A lens designed purely for the smaller sensor uses its entire covergae and is unsuitable for "full frame" SLRs.

It would be a lot more money and of debateable advantage. Noise should be lower in a full frame sensor as the individual photo diodes could be larger. But resolution would be the same, MP count for MP count, so as the manufacturers get better then the need for a full frame sensor should reduce.

Yes. A 50mm lens, for example, acts as though it were a 75mm lens in terms of its field of view.

A digital-only lens has an image circle that matches the size of the sensor. This makes the lenses smaller, less expensive to manufacture and also enables more ambitious designs to be attempted. 25 years ago a 12-24mm f4 zoom lens of professional quality would have been beyond belief. Now we have one, and at an accesible price.

Hope that helps, if you have more questions, please ask.

Loads more money. That's the reason we have smaller sensors. The cheapest camera with a 24x36 sensor costs over £4,000. Compare that to a K10D.

Yes. It's just a reference point for people familiar with film cameras.

G

Hi Zach,

It took me a while to find, but I posted this up last year as an explanation..

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in the above image, the larger (shaded) area relates to the size of the 35mm film plane, and the smaller area in the middle relates to the size of the digital sensor in comparison.

(And no pedantry points for noticing I got the depth of the sensor wrong in relation to it's width.. by the time I'd noticed, I'd already done most of it.. )




The above will be the two images, at a 100%.

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Hope that helps..

Cheers

Liam

Hello Everyone

Recently joined the Forum and I feel like I'me back at school, in fact
the first day at school. SO MUCH INFORMATION it makes me realise how little I know!

Will now play a low profile and listen, read and learn.

My thanks to all for the fantastic knowledge base.

Peter