[wim]

[quote name='Brightcolours' timestamp='1283620664' post='2485']

There is no other image "similar" in the dpreview galleries. None is in low light with light sources.



There are MANY (really MANY) images which show the ghosting problem, though.



Yes, the mirror surface is on the front surface (and as far as I know, that is always the case with plate beam splitters). If it was on the back, diffraction would mess things up, I guess.



DP review does not measure DR, even if they say they do. They use in-camera tone curves... and used JPEG output, while also noticing the detail eating strong NR.

A ghost image will not knock

Yes, it is caused by the mirror. No, it is not reasonable to blame it on something else.

Comparing it the the black dot occurrence from the 5D mk II just shows little understanding of that problem, and how totally unrelated it is to the ghosting issue.



Just in:

[url="http://www.imaging-resource.com/PRODS/AA55/AA55A4.HTM"]http://www.imaging-r...AA55/AA55A4.HTM[/url]

Sony A55V with 18-55 kit lens and flash usage:





Sony A560 with 18-55 kit lens and flash usage:









"When additional surfaces are added to an optical path, especially ones not parallel with the image plane, there is always a chance that light will travel an unintended path. In the case of the A55V and A33, it appears that the rear surface of the translucent mirror film can reflect light back to the front surface of the film, which reflects it back to the rear, causing a "ghost" reflection or multiple reflections to appear in the final image under certain conditions. The above left crop shows this phenomenon in one of our Sony A55V flash test shots, where a very strong reflection from the plastic edging of our flash-range/uniformity target also has a small ghost image in the form of a horizontal white line below it. (Thanks to IR reader Erick E for pointing this out in one of our flash range images!) The crop on the right is from a similar flash shot, taken with the same lens, but using the Sony A560 which is a traditional SLR without a translucent mirror in the optical path. As you can see, under nearly identical conditions (the A560's flash is a bit stronger), no ghosting is present."



" Based on our tests, we can confirm that this is a genuine phenomena with the Sony A33/55. Should you be concerned about it? Perhaps. Some people would certainly find it objectionable, especially if they did a lot of night photography of things like cityscapes. Personally, it wouldn't deter us from buying a Sony A55V, because we don't do much cityscape-type photography: Our night shots tend to be ones where the subjects are people or areas lit by nearby light sources. With these sorts of shots, ghosting of the type shown above wouldn't be an issue. Bottom line, you'll need to decide for yourself if this would impact your personal style of shooting enough to outweigh the benefits of the Sony A55's pellicle mirror design."



Images from A55V and A33 users:















[/quote]

Ok, thanks for this, I hadn't seen the other images yet. I wasn't aware of the non-pellicle comparison either. So, thank you for expanding on this and essentially taking the time to educate me more on this effect with the new Sony cameras. I hadn't expected the engineers not to check for this type of occurrence.



Anyway, this proves you were right and I was wrong, and I gracefully concede.



Kind regards, Wim