[TGoode]

hi, ive been looking at cheap manual focus portrait lenses on ebay and im a little unsure what i should be looking for? ive got a k30 any advise greatfully received

[Adam]

This one is an exceptional value:
Bower 85mm f/1.4 Manual Focus Telephoto Lens for Pentax SLY85P

We have an in-depth review of the Vivitar version on our homepage.

[TGoode]

This one is an exceptional value:
Bower 85mm f/1.4 Manual Focus Telephoto Lens for Pentax SLY85P

We have an in-depth review of the Vivitar version on our homepage.

will have a look thanks

[Just1MoreDave]

Almost everything in portrait comes down to "how far away are you from the subject?" If you knew that, or a range, or something like "in my house", you could then pick a focal length to match the shots you want to take (like head or full body). Then you could estimate how much depth of field you need, plug that into a calculator and see what the lens's maximum aperture needs to be. You could use a zoom lens that covers that range to test your theory, if you have one. It would narrow down your choices a lot.

I chose the opposite path, buy a lot of stuff and see what works for me. These are all my opinions, not facts. I like the 50mm to 135mm range.
50mm - I like the Pentax-A 50mm f1.4, but just about any 50 you like will work.
55mm - The Takumar 55mm f1.8 formula is similar from the Auto Takumar through SMC Pentax 55mm, f1.8 or f2.0, and inexpensive too.
58mm - If I had the money and opportunity, I'd get the Voigtlander 58mm f1.4. I have a CZJ Biotar 58mm f2 and there are Helios copies, but I don't like these for portrait.
70mm, 77mm - I would buy the Pentax lenses at these lengths but they cost actual money.
85mm - Many beautiful lenses at 85mm, three to five times what I'd pay for them. Go with Adam's suggestion here, the Samyang-made 85mm f1.4 sold under many brands, the best value.
90mm - I like the Tamron 90mm f2.5 Adaptall macros here, but there are a lot of 90mm macros that are close in performance.
100mm - A lot of 100mm f2.8 macros will do a good job here. The Pentax-M 100mm f2.8 works well too for non-macro use.
105mm - The Takumar 105mm f2.8 formula is good.
120mm - I like the Pentax-M 120mm f2.8 but it's hard to find.
135mm - SMC Pentax 135mm f2.5 is my favorite here. A lot of lesser 135s are sharp enough in the center to be fine for portraits too, and cheaper than the Pentax.

It's worth getting the KA mount because you have more flexibility with flash, but a lot of these lenses only come in manual-aperture versions.

I have one or more lenses at 50, 55, 58, 85, 90, 100, 120 and 135. I can't really pick a favorite but my best portraits are at 50mm, mostly with the Pentax-A 50mm f1.4.

[baro-nite]

A Pentax-M 1:1.7 50mm would work well if you don't find a fully manual lens, and can be had for under US$50. One of the best bang-for-the-buck lenses out there.

[JimJohnson]

Just sold my Sigma autofocus 35-70mm. In my opinion, the slight softness and focal range makes it perfect for portraiture on APS-C cameras. However, I do very little portraiture and it was sitting too much on my shelf.

30 years ago, photographers paid a premium for soft lenses; today the pendulum has swung the other direction. So, if you can find one, this lens is a terrific bargain.

[TGoode]

thanks for the advice guys

[Na Horuk]

So yeah, something with focal length between 55 and 85mm, fast aperture, probably a prime and not a zoom (though, modern zooms can be pretty great, too). 135mm was also a classical portrait focal length, but on crop sensors it becomes a little tight.

[TGoode]

anyone no anything about horusbennu 50mm f1.7? brand new on ebay £42 seems like a steal to me,

[baro-nite]

anyone no anything about horusbennu 50mm f1.7? brand new on ebay £42 seems like a steal to me

HorusBennu 50mm F1.7 MC (PK) Lens Reviews - Miscellaneous Lenses - Pentax Lens Review Database

Looks like about the going rate. I'm not sure, but I gather this is a fully manual lens, i.e. no A setting. In which case it is functionally comparable to the Pentax-M 50/1.7; compare reviews here:

SMC Pentax-M 50mm F1.7 Reviews - M Prime Lenses - Pentax Lens Reviews & Lens Database

Take all reviews with a grain of salt. Very possible that there is a bias in favor of Pentax lenses. Still, there is loads of evidence that the Pentax-M 50/1.7 is an excellent performer and outstanding value.

[NitroDC]

A Pentax-M 1:1.7 50mm would work well if you don't find a fully manual lens, and can be had for under US$50. One of the best bang-for-the-buck lenses out there.

+1

The M 1.7 is one of the sharpest lenses out there.

[JimJohnson]

Each to his or her own, but I don't want the 'sharpest lens out there' for portraiture. I don't want to spend the time smoothing the wrinkles, blemishes and zits. I want to capture the twinkle in the eyes, the glow of the skin and hair.

[Lowell Goudge]

So yeah, something with focal length between 55 and 85mm, fast aperture, probably a prime and not a zoom (though, modern zooms can be pretty great, too). 135mm was also a classical portrait focal length, but on crop sensors it becomes a little tight.

I still like the 135 for outdoor portraits. I specifically use a preset F2.8

[TGoode]

just brought a pentax m 50mm 1.7 on ebay for £26 this will only work in manual on my k30 if im not mistaken?

[baro-nite]

just brought a pentax m 50mm 1.7 on ebay for £26 this will only work in manual on my k30 if im not mistaken?

You can also use it in Av (Aperture Priority) mode, with the lens always at maximum aperture. Occasionally useful. Congrats on the lens.