Pentax 50mm lens questin

[el baroda]

Hi,

 

I am new to the Pentax forum. I own both an M and an A version of the

50mm f/1.7. The M version is in perfect mechanical condition but it

has a ring of fungus on the rear element. Despite this, the photos it

takes are quite sharp. On the other hand, the A version is perfect

optically, no fungus, but the aperture ring is in bad shape. It is

very hard to turn and the aperture does not close down beyond f/8.

Your comments or suggestions on the following will be highly

appreciated:

 

1. Should I have the M lens cleaned of the fungus, or should I have

the aperture ring or blades of the A lens fixed? Which is the better

option as far as recurrence of the problem is concerned?

 

2. Or should I keep them as they are and save up for an f/1.4? Which

is better the better version - M or A?

 

Thanks a lot.

[jimvanson]

It's too bad but it will probably cost more to repair one of the lenses then it would to replace it.<p>Your idea of "<I>should I keep them as they are and save up for an f/1.4?</i>" is the one I'd have suggested.<p>And finally; Here is the addresses of two good sites; The

<a href="http://www.photo.net/bboard/q-and-a-post-reply-form">Pentax Forum</a> and <a href="http://digilander.libero.it/aohc/selartice.htm">AOHC Website</a>...perhaps they can help you with Pentax specific questions.

[stemked]

Hello El.

 

First of all, fungi produce spores, spores drift in the air. I would highly suggest getting that lens away from your other equipment before it too becomes contaminated. You might also want to drop a silica packet or two in your bag to remove some of the moisture. I would put the lens somewhere where it can get some direct sunlight (not too hot mind you) so that the UV light will kill the organism

 

And I completely agree that getting it cleaned is a waste of time and money. With a little looking around I would be very surprised if you would have to spend more than $35 on a 'new' used one. Even the A lens (which by the way is a fantastic lens) is still pretty cheap. I picked one up for just $45 myself.

 

As far as which 1.4 lens this is one of the few examples where the A lens is better than the M lens wide opened. Not to say the M version is bad at all, it just isn't as steller as the A lens.

 

This may not be the proper place to note this but I have an M 1.4 version my wife and I got with another camera which I would be willing to sell to you if you are at all interested(we can do this off forum). Now it is missing the rubber focusing ring, but last time I checked, the glass and everything else about it was fine. If you are interested I'll ask my wife if it is ok to sell, check it out first to make SURE it is ok (it sounds like you've had enough lemons already).

[george_verbryck]

Well as the 50mm lens is the one I used most on my pentax gear,I bought several and found that they were all good. I had a 1.7 2.0 three 1.4 all M and a A1.4 and a pentax 1.4 . After I picked up all of these lenes I did some testing and found that sample variation had more to do with it than any thing else. The 2.0 was the sharpest wide open and was excellent all around but since i wanted the faster maximum aperature I took the second place which was one of the pentax M1.4, the A lens of the same aperature was not nearly as sharp and just to make sure I tested them side by side for a while and even in non scientific testing it proved the M the better lens. 50mm pentax lenes are cheap and I would venture to guess ricoh lenes cost even less if i were you I would buy a few working ones and test them then resell the ones that did not make the cut.That is what I did. Cheers George

[el baroda]

Thank you all very much for your comments and suggestions.

 

Cheers.