Luminous Landscape Forum

Equipment & Techniques => Medium Format / Film / Digital Backs – and Large Sensor Photography => Topic started by: MauiPhoto on August 03, 2013, 04:30:32 pm

Title: Bubble on Rear Element Normal? - Schneider 90m f5.6 Super Angulon XL
Post by: MauiPhoto on August 03, 2013, 04:30:32 pm

I have another technical post.. My Schneider Linhof Super Angulon 90mm f5.6 has a tiny mark / bubble on the back of the lens element.  

The bubble or spec is about the size of pin prick or ball point pen. Tried cleaning with fluid and lens tissue but no luck.


Is this normal for Schneider lenses?  Could this affect picture quality or cause flare?  

See picture attached.  Using this lens on my Linhof 617 sIII

Thanks!
Q

Title: Re: Bubble on Rear Element Normal? - Schneider 90m f5.6 Super Angulon XL
Post by: Graham Welland on August 04, 2013, 02:12:46 am

Probably invisible. If it's a new lens however I'd return it and get a replacement if only because re-sale will be seriously affected.

In reality it probably won't make any difference in real world images although rear elements are affected more than say front elements.

I recommend taking a look at the lensrental.com blog for a realistic evaluation of defect vs visibility.

Title: Re: Bubble on Rear Element Normal? - Schneider 90m f5.6 Super Angulon XL
Post by: MauiPhoto on August 05, 2013, 03:58:35 pm

Upon further inspection, I think it just a small piece of dust that is setteled behind the rear element.

It also seams that its location is not behind center optical path of the lens so it is nothing to worry about.

Thanks for the input.

Q

Title: Re: Bubble on Rear Element Normal? - Schneider 90m f5.6 Super Angulon XL
Post by: DanielStone on August 06, 2013, 12:56:13 am

I wouldn't worry about it at all. Just keep shooting :)