Veiling Flare with Alpa Kern Macro Switar 1:1,9/50mm

jaapv said:
Central veiling flare is mostly a result of internal reflections inside the lens. Check whether it has lost any of its inside antireflective paint as far as you can see. Otherwise the black edge paint on the elements may have been damaged in an earlier repair. The nastiest possibilities would be balsam separation on a cemented element (does this lens have one?) or internal haze (which can be removed) or fungus.
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yes

I had the same issue with a brand new summicron 50.
it happenned to be the rear black paint that was glossy, and reflected strong lights just at the edge of the field. Nothing that the hood could help with.
I discovered it by playing with the lens in front of strong lights with the shutter open an da screen in place.
I got the area repainted with matte paint and the problem is gone.
 
To me it seems like the filter is too far forward from the front element, and not deep enough into the shade.
 
I use the Kipon adp for alpa to nex and alpa to leica M both work without any problems. Since you are in HK I am sure you could find someone who has it in stock and try before buying. That is if you do not have a Kipon adp at this time.

wbill
 
I took some photos using the phone with some nasty flash but I think it does the job of telling that the aperture blades are too shiny :(

1)

IMG_3367.jpg by Billy W, on Flickr

2)

IMG_3368.jpg by Billy W, on Flickr

3)

IMG_3375.jpg by Billy W, on Flickr

4)

IMG_3376.jpg by Billy W, on Flickr

I think from pics 3 & 4 can clearly see how shiny the aperture blades are and I think there are signs of what jaapv said before: black paint around the edges of the lens have gone.

When I shone the iPhone torch in from the front of the lens and me looking from the back of the lens, I could actually see some reflection of the aperture blades. I think this might be the cause of my veiling flare on my copy of this lens.

Can the blades be made matte in a CLA?
 
I have never heard of aperture blades causing a similar problem, blades are never painted or 'blackened.' It seems more likely to be a problem with the inside barrel...

Here is a photo of a 50/1.9 I used to own, it's all black inside...
 

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_sgb_ said:
I took some photos using the phone with some nasty flash but I think it does the job of telling that the aperture blades are too shiny :(

1)

IMG_3367.jpg by Billy W, on Flickr

2)

IMG_3368.jpg by Billy W, on Flickr

3)

IMG_3375.jpg by Billy W, on Flickr

4)

IMG_3376.jpg by Billy W, on Flickr

I think from pics 3 & 4 can clearly see how shiny the aperture blades are and I think there are signs of what jaapv said before: black paint around the edges of the lens have gone.

When I shone the iPhone torch in from the front of the lens and me looking from the back of the lens, I could actually see some reflection of the aperture blades. I think this might be the cause of my veiling flare on my copy of this lens.

Can the blades be made matte in a CLA?
Click to expand...
It looks like somebody polished the inside of the mount as well.
 
I would think this is exactly the cause of the flare - everything in the lens barrel should be matte black and the blades at worst should have a dull finish ..... Wondering why everything is so polished looking
 
Thanks to all who helped me with the diagnosis but now begs the question where to get a proper CLA and request what to be specifically looked at during the CLA.
 
I had a Leica lens where the internal black paint came off, there were black paint chips rattling around inside. I sent it to DAG and he repainted. There should be a tech in HK that can do this...
 
I had a [much less expensive in it's day] Meyer Oreston 50mm/1.8 that was sold with my Practika Super TL in 1969. That lens had the same shiny, spring-steel-looking aperture blades. It flared big time against the light.
It is possible that if you were able to ask the people at Kern why the lens has shiny aperture blades, which cause flare when the lens is aimed against the light... that they'd reply 'Why would you ever shoot against the light?'
 
pluton said:
It is possible that if you were able to ask the people at Kern why the lens has shiny aperture blades, which cause flare when the lens is aimed against the light... that they'd reply 'Why would you ever shoot against the light?'
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ROFL

I had been looking at product shots of other macro-switar 1:1,9/50mm and they all have shiny aperture blades and mine just looks a little more shinier than them.

I'll ask the techs in HK whether they can repaint the glass edges, dull up the blades and blacken the inside of the barrel.
 
I went out and shot with my Switar today and my aperture blades look the same as yours, plus when I looked down into the lens with a flash light it appears to be the same as yours. Yet I have no flair issue like I see in your pictures, now I do not use any filters with my lenses so that could be a difference. I wish I could give you something helpful but I am at a loss unless it's the filter but I must say that does not make a lot of sense. Also today would have been perfect for flair as it was badly overcast but still bright for about a hour this afternoon.

wbill
 
Thanks wbill for checking your lens against mine.

Like you said, veiling flare as a result from the filter doesn't make much sense given the inside of your lens is similar to mine. Was planning to do some shooting with the Switar last weekend but looking at past photos made with Switar I noticed that the veiling flare occurs when the background is comparably brighter than the foreground or when you trying to shoot a middle-third central background that is comparably brighter than the left and right thirds of the frame.
 
I have two FED lenses that are similar, one of which shows central flare like your Switar. I took a photo that shows the loss of black coating on the edge of the lens is most likely the cause. Flarey FED on left, comparatively good on right:
left_flare.jpg
 
mcfingon said:
I have two FED lenses that are similar, one of which shows central flare like your Switar. I took a photo that shows the loss of black coating on the edge of the lens is most likely the cause. Flarey FED on left, comparatively good on right:
Click to expand...

Thanks for your efforts mate!

I think more and more that it is the loss of black paint around the glass edges are the culprit!
 
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