I didn't use a filter and I'm pretty sure that the lens is perfectly clean - but I'll check again. I did use a lens hood for both the kit and Rikenon. All we are seeing, I think, is the difference in IQ of the two lenses at f5.6. At f8, the kit lens is quite a bit sharper.

The really interesting bit is that the Rikenon is the lens that came with a Ricoh KR10 I bought several years ago for £15 on Ebay.

Cheers
Andrew

I've taken several test photos with the Rikenon 50mm f2 and Pentax 18-55mm MK2 kit lens at 50mm. I have yet to see one where the Kit lens come close.

I leaned over the garden fence this morning and took several more at f5.6 1/500sec at ISO200. I checked all the Kit lens photos and they look identical. Some were taken using auto-focus and some were focussed manually - no difference between them. All the shots were taken as RAW and processed identically using RawTherapee.

These are 100% crops ........

First the Kit lens



and the Rikenon



The Rikenon seems way sharper to me. There is less difference at f8 - but still noticeable.

Cheers
Andrew

I've got exactly that lens too, also from a KR10 Super from the same era. It is sharper than the 18-55mm MK2 kit lens at 50mm f8 and much sharper at f5.6.

Cheers
Andrew

If there are any "hard-up" photographers reading this who just happen to live locally to me, just let me know and you can have one or both of Takumar/Mitakon zooms for free.

Cheers
Andrew

For your amusement, here are a few 100% crops that seem to illustrate just how un-stellar two of the lenses are. The shots were taken in the evening under artificial light - those low energy bulb thingies that the government seem to have decided that we must all use. The subject is some piece of junk mail that came through my letterbox earlier in the day. I make no great claims as to the rigour of the testing methodology but it seems to have been good enough to distinguish (hopefully reliably) between the lenses.

In all cases, the lenses were mounted on a Pentax K200D on a substantial tripod. A cable release was used and the camera was set to the 2sec delay that locks up the mirror. All photos were taken at f8 for 1 sec, with the K200D sensitivity set to ISO 200. The focussing ring was twiddled with the shutter release half pressed until the "in focus" hexagon could be seen in the viewfinder - so the K200D thinks they are in focus. All photos were taken as JPEGs and other than cropping, I haven't fiddled with them in any way.

This is a resized version of the subject - taken by the Sigma mini-tele 135mm f2.8 lens.




The following are 100% crops taken by each of the tested lenses.

Mitakon 80-200mm zoom. Mmmm ........



Pentax 75-150mm zoom. Much better.



Takumar 80-200mm f4. Oh dear.




Sigma 135mm mini-tele. Not bad.



My interpretation is that the Pentax 75-150mm F4 zoom and Sigma 135mm prime are fairly close - with the Pentax just shading it.

The Takumar and Mitakon lenses are ......... not very good. If I were to try to sell them on Ebay, I'm not sure how I'd word the advert. Any suggestions?

Cheers
Andrew

Today I did a bit more testing - and now I am (fairly) sure. The Rikenon 50mm f2 is a little sharper than the 18-55mm kit lens at 50mm both in the centre and at the edges.

I also took a few shots with the Sigma 28mm - and that is pretty good too. It also is sharper than the kit lens at 28mm right across the frame but the difference is so slight that for a different scene on a different day, in different light - who knows my impression might be reversed in favour of the kit lens.

So, of the old lenses - Rikenon 50mm f2 is fine - the Pentax 75-150mm f4 zoom, Sigma 135mm and 28mm primes are OK and the others can be consigned to the bin.


Cheers
Andrew

One lens I forgot to mention (probably because it really is very forgettable) is a Mitakon 80-200mm zoom (and a couple of 2x tele converters). I've been doing a little testing and am pretty sure that the Mitakon and the Takumar 80-200mm zooms are best consigned to the skip. At 135mm, they are very fuzzy compared with the Sigma 135mm prime, especially at the centre. Oddly, the Takumar is quite sharp at the edges - maybe it's been dropped at some time in the past.

The Pentax 75-150mm f4 zoom seems much better. It is sharper than the Sigma 135mm in the centre but a bit softer at the extreme edges. I'm not sure about the Ricoh 50mm f2 yet. A couple of shots suggest that it's at least comparable to the kit lens, though I need to do more testing before I can be sure.

I must admit, I haven't got completely used to the notion of trusting the camera to focus for you or of it deciding on exposure either. Maybe I'm too much of a geek. I fancy that there's a chance I'll end up using the K200D as though it were a manual K1000 film camera.

Cheers
Andrew
(I still play vinyl LPs too)

No, the 50mm Rikenon f2 that I have doesn't have the pin that locks the lens onto the Pentax. I have a 35-70mm Rikenon zoom that does - so it's staying on the KR10X.

Cheers
Andrew

Just before Christmas, I bought a Pentax K200D with 18-55mm Mk2 kit lens. I've a few K-mount lenses that I used with a Ricoh KR10X that seem to function OK on the K200D - but I'm not completely sure that any of them are really significantly better than the kit lens.

FWIW, they are:

Rikenon 50mm f2
Rikenon 35-70mm (yes, I know that one jams, so I won't be trying it on the K200D - it can stay on the KR10X)
Sigma 28mm mini-wide
Sigma 135mm mini-tele
Takumar 80-200mm zoom
Pentax-M 75-150mm zoom (picked up recently off ebay)

I've never done any macro photography before - so I'm going to buy some extension tubes and have a play with those. My bet is that I'll mostly use the kit lens and the Pentax 75-150mm and the others probably only rarely (50mm with extension tubes for macro, I guess).

I haven't been terribly serious about photography in the past, largely due to lack of time. Now that I've retired and don't have to worry about how to earn my daily crust, I think I've got a whole new world to explore.

As a rule, I've generally used the KR10X mostly totally manually, so most of the K200D functionality might not get used for a while until I "get the feel" of it.

I love the forum; have been lurking about for a bit and have learned quite a bit.

Cheers
Andrew