50mm lenses

Hi everyone.
A lot of different types (models, apertures, etc) of 50 mm lenses are on ebay or on the second hand market.

pentax 50mm

I suppose everyone is compatible with k20d, but which one of them is good quality?
1- Is bigger aperture always equivalent to better quality?
2- and above all, which are advantages /disadvantages of manual focus?

I read old post, they says to stay on the "A" series. Any other suggestion?

thank you

Although I love the M and "K" series lenses, you will find the A-series easier to use. With the aperture set on A you can use all the auto settings P;Av;Tv. With an M or "K" lens you have to use manual mode.

The good news is quality wise they are as good as each other. A bigger aperture does not in itself mean better quality (depending how you define quality). In terms of sharpness the 1.4 and 1.7 seem to be the most popular, and of course both will need stopping down to around 5.6-8 to achieve the sharpest image. Having said that, they will both produce outstanding results wide open. The 1.4 generally fetch higher prices.

The best value are the 2.0 which are not so popular, but still produce excellent results.

Peter, very helpful and direct reply!

I'm not confident I can get good result with MF. Is it only because I'm lazy to shot in AF? In other words, is it easy to shoot with MF, without be able to have the AF?

For curiosity, why there are so many 50mm manual focus lens on sale?

If you have a lens that has auto aperture you can use all camera modes, and if you've more modern lenses you can use select focus and such, don't ask me how it was

It really depends if you need the f/1.2 if not then the f/1.4 and f/1.7 are probable sharper and also cheaper.

Set your focus on manual focus and find out it.

ps. Peter was faster, I was trying to find the list with lens restrictions, found a good one a few days ago.

If you've got £150 to spend,get a new FA 50mm 1:1.4. You'll not regret it.

Why so many available? It's probably due to the fact that almost every Pentax 35mm manual focus SLR from the MX onwards was sold with a 50mm lens of some sort as standard. That's a lot of cameras and a lot of lenses that have lasted longer than the camera they were sold with and are now available because numpties perceive they don't need them now that they have 'gone digital' .

The most common is probably the SMCP-A 50mm 1:1.7. The f2 version (not 1.2) was sold with later models.

The f1.2 lens was only produced in original K mount and the later A series. It's expensive but if you need the fast aperture for low light it's worth considering.

The bottom line is for around £50 you'll get a very good lens.

Caution: Check the aperture ring of any A series 50mm lens They are prone to sticking due to a broken leaf spring mount. It's fixable, with patience, but best avoided if possible.

What Stefan suggests is a good idea. Try manual focus yourself with your current lens. However, modern AF lenses dont have the smooth and long focus throw that the older lenses have. It is easier to manualy focus a manual lens.

But to be honest if you are to go down the manual focus route I suggest you get a split prism focus screen for your camera. Katzeye are expensive but i have had good results with a Chinese made one off ebay.

You will find it more than useful even with a AF lens. I tend to manually focus most of the time now. The smaller and darker view with a crop digital sensor makes manual focus harder than it was on a 35mm camera without a focus aid like split-prism.

I don't suppose you've got a link to the type of split focus screen you've got?

On topic, I'm pleased as punch with the 50mm F2 I got on eBay for about £15 including postage. It's sharp, crisp, good colours, and has (I think) a lovely bokeh.

On a digital body, you're getting around a 75mm apparent focal length, so good for portraits and short tele work. I'd imagine they're so cheap because 50mm would have been a pretty standard lense for 35mm SLRs back in the day.

Oh, yes, and did I mention it was £15 quid!

The manual focus ones are cheaper. There are so many on sale because they were made in large numbers and often supplied with cameras.

Focusing with them is difficult for some subjects, but it's easy a lot of the time even without a special focusing screen. Then you can judge by the matt field or use the camera's electronic focus indicator (the green hexagon).

Search the forum for more comments on the various Pentax 50mm lenses.

Thank you everyone for your help.

So, to sum up, both f1.4 and 1.7 are ok, and also f2.0 (cheaper) and 1.2 (more expensive).

I would say the worst aspect of a pure MF is that you can't have an AF if you need it, but the difference in price is huge. about £30 against £155 for the cheapest 50mm AF f1,4 (no many shops sell it)

Max

I think you should try and prioritise what you want from the 50mm you eventually plump for.

As Mannesty suggests the FA50mm 1.4 (autofocus and exposure) is fantastic value for it's price and will the easiest to use. I dont have one, but I hear nothing but praise for it.

If you go down the manual focus route, get an A- 1.4 or 1.7, and try out a split-prism screen with it.

The K + M lenses require more work getting the exposure right but are an absolute joy to use. Split prism is the way to go with these too. Again the 1.4 or 1.7 are both cracking lenses.

The 1.2 is a heavy (and expensive) beast. You will pay more for one of these old lenses than a FA50 1.4 new !

Do an ebay search for split prism. I think the seller I bought from was virtual village.

My best ebay purchase has to be this lens http://www.bdimitrov.de/kmp/lenses/primes/normal/K55f2.html

I won it for £1.00 plus £4 postage !

The Pentax F 50/1.7 hasn't been mentioned and it works perfectly in all respects

You can use "capture in focus" I believe.
So you press the shutter release button and move the focus and when the camera comfirms focus it will make a photo, sometimes that even works better then autofocus.
Don't ask me more about it, I don't know much besides the fact that you can do that and having it used a half year ago a couple of times. I'm sure someone here can tell you more.

I use manual lenses a lot and I think the old Pentax ones are superb.

What I have found to be a good method with manual focus lenses is to put the camera in auto focus mode then press the shutter button fully down (after first setting exposure) and then adjust the focus ring. In this mode the camera will fire the shutter only when the image is in focus.
I have tried it and it gives really good results.

To deal with exposure on fully manual lenses, you will have to go into your camera menu and 'permit use of aperture ring'. Then to set exposure, put the camera in manual, adjust the aperture ring on the lense to the value you want, then (on my camera) press the AE-L button and the camera selects the correct shutter speed.

This is all based on the K100D but I am sure you will be able to make these settings on your model.

Just to note on pricing, I've been watching and bidding on the 'bay for Pentax-A 50mm f1.7 lenses for about two weeks now (I've not managed to win an auction yet) and they seem to be going for upwards of £50 inc postage right now. There are always a few for sale but clearly a lot of people in the market to buy them at the moment - and here's me hoping they would be pocket money prices...

I'm considering waiting another month and just buying a new FA 50mm f1.4 given the possible variable quality of an ebay purchase etc etc...