Hi Team,

I've been shooting a bit lately but I've had little time to post
process the images or even check my PDML mail. School holidays, kids
birthdays and a big burst of work came my way, the additional cash has
allowed me to clean up a lot of loose ends. I have been doing repairs
for work so I'm in repair and restore mode currently. I just finished
fixing a few things in my car that had failed and I did some toy
repairs, a phone touch screen replacement (a nightmare even for me)
and a few computer repairs too. More car repairs to go but I'm much
happier that the half dozen icons and messages have disappeared from
my view whilst driving.

After testing my 77ltd for flare performance against my old A50/1.2 a
few months back and being totally disgusted with its contrast
performance I decided to finally determine what is actually causing
the problem.

Contrast comparison:

https://dl.dropboxusercontent.com/u/9304908/temp/77LTD%20contrast%20test%20IMG503059.jpg

Test shot (jpg out of camera), still sharp just no blacks whatsoever:

https://dl.dropboxusercontent.com/u/9304908/temp/IMG503052.JPG

So I embarked on the task of pulling my 77 apart, not something that I
had great enthusiasm for I must say. The last/rear element is fixed
and comes away with the rear mount, that left me staring at the rear
group, which I then unscrewed from the lens body. In this assembly the
first two elements are cemented and the rear element of the group with
an internal air-gap. Looking at the external surfaces there was no
noticeable haze and looking into the group from the concave element
that sits closest to the aperture it appeared very clear.

https://dl.dropboxusercontent.com/u/9304908/temp/13488_pentax_77_bud.jpg

However it was a very different story looking into the lens set from
the rear, there was a definite haze visible and tilting the lens with
a light shining through it was plain to see where the contrast was
being lost. Not good, this means that the considerable haze is locked
inside the sealed and aligned 5th and 6th elements, damn. So I now
have to trek down a path that I was hoping not to have to and of
course I can't locate my lens wrench so as soon as the shiny new one
that I just ordered arrives I will set about setting free delicate
glass elements in my currently expensive paperweight. I will let you
know how it pans out, hopefully for the better.

Curiously the chassis of the 77LTD is high density polymer :)

https://dl.dropboxusercontent.com/u/9304908/temp/IMAG3228.jpg

Cheers,

--
Rob Studdert (Digital  Image Studio)
Tel: +61-418-166-870 UTC +10 Hours
Gmail, eBay, Skype, Twitter, Facebook, Picasa: distudio

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