Weird exposure problem

mrred

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aka digital
 

Bill Burk

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I've only ever seen the Pentax non planar filter advertisements once in 65 or so getting one in your size probably mission impossible.

There are two on eBay right now.

One you have to buy the whole camera to get....

Search for ASAHI PENTAX 49 UV GHOSTLESS JAPAN

And you know. I can't see any similar ghosts with this darn thing. Now I know what belongs on that M42 SMCT 1.4, it works and it's authentic.
 

Xmas

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Excellent advice
I always use a deep hood as well preferably rubber.
But I like the single coated signature (pastel) with colour and the adaptive compression in mono.
So I have two sets of LTM lenses SC and MC.
A hood keeps the sun, fingers and sea gulls away from optic surfaces.
I've had a lens drop out of a gbag (concrete) and land on folded rubber hood bounce and nearly caught it on half volley it then landed on back cap. The lens was unmarried apart from paint witness on aperture ring paint. Lenses always seem to land filter ring or registration plate down.
 

Xmas

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But the girls camera will need 48 or 52 mm a 48 to 49 step is ok but a 52 to 49 may v*****tte.

Thanks for the search clue another bout of nostalgia today may need to step outside with the K1000 and make believe it is a Sv.

Most of my night shots are on a sonnar LTM from '50 it has only six air to glass surfaces with deep curvres to spread reflections cause of the low refractive index glass.
 

E. von Hoegh

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Goes without saying.
On LF I use a compendium with a mask, about half the lenses I use are uncoated. A hood makes a difference, regardless of the coatings on the lens.
 

wiltw

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my only guess as to what caused this was internal reflections from somewhere within the pentaprism..

 
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John Koehrer

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Thinking(new experience) about it, you're correct. But there is a possibility that light could bounce off the back of the lens. Remember., it's not a mechanical bumper, it's a light seal.
 

Jim Taylor

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Agree with everything you've said. Which is why when it happened to me I was so perplexed when covering the VF eliminated the problems. Maybe just 'one of those things'!

Like I said, it happened to me taking night shots at the Vatican. Maybe it was really angels....
 

Xmas

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you get the same effect with rangefinders...
 

Bill Burk

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you get the same effect with rangefinders...

Of course with a rangefinder, there is no path to the film which blocking the rangefinder eyepiece can possibly affect. (Unless you remove the top-cover and spoil the camera's light-proof design).

My Pentax ES-II includes a viewfinder blanking mechanism which serves to keep the memory of the exposure from being impacted by light coming through the finder. I do not expect that it would affect anything but exposure calculation.

No, I can demonstrate the issue in this thread is entirely due to a flat filter, and is entirely alleviated by using a GHOSTLESS filter. Even if light struck the edge of the mirror because of lost foam, which could feasibly turn the edge of the glass mirror into a prism, the image would be inverted, but mirrored left-right.
 
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