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NEX-7 has an AA filter.

V

Vivek

Guest
I opened up the NEX-7 to "fix" it. I was surprised to find an extra piece of clear "glass" (dichroic coatings on both the sides).

To me this seems to a "blur" filter they added. I have now removed it.

None of the earlier NEX' appear to have this. The dust shaker is also the UV/IR cut filter.

One other thing, the copper heat sink is quite well connected to the front chassis (with the mount) which is a piece of moulded aluminum.

I am trying to put the camera together to bring to life again. This is not easy (too many short flex strip cables).
 
V

Vivek

Guest
Will do if I manage to put the camera back to working order (at the moment it is not).

The "clear filter" they have put in between the sensor and the dust shaker (which is also the UV/IR cut filter) cuts UV at around 350nm. I do not see any point in having that since the dust shaker itself cuts off UV. The "clear filter" is also transparent to near IR.

This might prove to be a very costly experiment for me but I have been able to confirm one of my hunches- Sony made a mistake with the sensor module. The optical path is screwed up. They put a gasket and that thin filter with the same baffle that is in every other NEX without taking into account the refraction of that thin glass. It is a basic design flaw leading to soft corners, etc.

I would be very careful about buying any Sony cameras in the future (I was about buy a F3).
 
V

Vivek

Guest
If you read the comments there, Jay opened up the sensor module (not completely) upon my request.

What is shown there is the dust shaker and the sensor module with a plastic frame, underneath that frame is the "clear glass" plate and under that is a silicone gasket sitting on top of the actual sensor.

Pay attention to what is written, please.

Here is the sensor (left, the plastic frame, right the "clear glass" with the gasket):


Untitled by Vivek Iyer, on Flickr

"Clear glass" with the gasket in front of the sensor:


Untitled by Vivek Iyer, on Flickr

"Clear glass" and the dust shaker (UV-IR cut filter, it is the blue green glass):


Untitled by Vivek Iyer, on Flickr
 
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philber

Member
Vivek, thank you for this fascinating info. Two elements prevent me from following your idea that this is purely a mistake. One is that I doubt that Sony would incorporate anything useless, simply because a manufacturer tries to keep cost down, not push it up with needless harware. Second, because soft corners exist on all other cameras with lenses sitting very close to the sensor, not just the NEX 7. That said, I would love you to be right, because that would pave the way for Sony to give us a NEX 7N that would be free of corner problems, and maybe even betetr on other parameters, including cost... Go, Vivek!
 
V

Vivek

Guest
7N or i7 is what I would love to have, Philber.

Every time I use the C3, it amazes me how good it is. There is no chance it has offset microlenses. The C3 and 5N do not have anything other than the UV-IR (dust shaker) filter.

I would speculate that the "clear glass" is a blur filter and is there mainly for the video.

You are right they don't add anything if it would not have any function.

I hope that I can make the 7 working again and the first lens that will mounted for a test shot will be the C-V 15/4.5. If that works as well as it does on the C3 then what I said about refraction and the light path/baffle (works like a built in vignetter) will be confirmed.
 
V

Vivek

Guest
Vivek, thank you for this fascinating info. Two elements prevent me from following your idea that this is purely a mistake. One is that I doubt that Sony would incorporate anything useless, simply because a manufacturer tries to keep cost down, not push it up with needless harware. Second, because soft corners exist on all other cameras with lenses sitting very close to the sensor, not just the NEX 7. That said, I would love you to be right, because that would pave the way for Sony to give us a NEX 7N that would be free of corner problems, and maybe even betetr on other parameters, including cost... Go, Vivek!
Philber, There is a experiment you can do to simulate what I proposed.

Add vignetting in the rear to one of your M mount lenses ( attach a thin black paper ring in the rear temporarily) and see what happens to the corners in the images taken with that set up.

Also, add a center filter* to the rear of one such lenses ("symmetric" design) and check what happens to the color shifts.

* a black marker and a small spot (removable using alcohol and a gentle wipe afterwards) on the center of the rear element of a lens would suffice. No need to think about custom center filters. :)
 

mazor

New member
7N or i7 is what I would love to have, Philber.

Every time I use the C3, it amazes me how good it is. There is no chance it has offset microlenses. The C3 and 5N do not have anything other than the UV-IR (dust shaker) filter.

I would speculate that the "clear glass" is a blur filter and is there mainly for the video.

You are right they don't add anything if it would not have any function.

I hope that I can make the 7 working again and the first lens that will mounted for a test shot will be the C-V 15/4.5. If that works as well as it does on the C3 then what I said about refraction and the light path/baffle (works like a built in vignetter) will be confirmed.
Hi Vivek, could that extra glass you find on the nex7 sensor assembly be already built into the nex5n sensor, hence why it does have that extra glass?

Still think the magenta cast and softer corners is due to the higher resolution, hence smaller pixels, and possibly deeper photosites.
 
V

Vivek

Guest
Hi Vivek, could that extra glass you find on the nex7 sensor assembly be already built into the nex5n sensor, hence why it does have that extra glass?

Still think the magenta cast and softer corners is due to the higher resolution, hence smaller pixels, and possibly deeper photosites.
No and no.

The sensor of 7 I show above also has a permanent glass seal (sealed with epoxy) just like the one found in a NEX-5N's sensor.

I have taken the sensor cover glass off from a NEX-5N' sensor. It is a simple, uncoated, float glass with a sharp UV cut (found on every sensor). Nothing more.

The "clear" glass I find in a NEX-7 has dichroic coating on both the sides.

Just to clarify- this "clear" glass has nothing (directly) to do with the NEX-7's behaviour towards RF lenses. It is light baffle- the piece of 5 cent plastic that sony put on top of that that isn't wide enough to account for the refraction brought about by that glass in the optical path.

On that second question- try the experiments I suggest above. I have done that on the stock NEX-7 before opening it up. There is a lot of thought, effort and time gone into this.
 

mazor

New member
no doubt Vivek, appreciate all these insights into the heart of nex 5n and 7, hehe. So you think the additional glass is an AA filter for nex 7. But I am pretty certain the 5n also has an AA filter, and if this extra glass is absent on the 5n, where is the AA gone? It is hopeful thinking that the 5n does not need one ;)
 

Taylor Sherman

New member
The 7 should need *less* of an AA filter given the higher spatial frequency it can handle due to the denser pixels.

But, the 7 is roughly the same "generation" as the 5, not 5N, right? So I wonder how things look inside a 5.

Regardless, it's interesting but mostly what I'll be interested in is the effect that its removal will have on the photos :)
 

thrice

Active member
ADMIN NOTE: Comment removed because it was not in keeping with the rules at GetDPI. Seriously folks, sarcasm does not belong in a thread where somebody is trying to share information. Let's keep it positive going forward.
 

hot

Active member
I am not a friend of DIY solutions, better it is to go out and make photos (with this excellent camera),
but Vivek sure has ultra clean rooms like AMD or INTEL for producing high level microprocessors :D
 
V

Vivek

Guest
Thank you for your sage advice and the remarks of others! Very useful indeed! :D

I would rather make photos than fiddle around with finicky flex strips and fragile plastic parts. FWIW, I am going to be on a hiatus for a while. Google to see any news on this elsewhere. :salute:
 

alba63

New member
I am not a friend of DIY solutions, better it is to go out and make photos (with this excellent camera) but Vivek sure has ultra clean rooms like AMD or INTEL for producing high level microprocessors :D
Thank you for continually teaching everyone with your superior insights and striking cleverness about what is best, here and elsewhere (aren't you "Knallberto" on dpreview?)
:banghead:

Bernie
 

douglasf13

New member
Good work, Vivek. I suspect you're right that improving video moire may be the culprit, and, if so, it echoes why converging video and still images isn't always a great idea.

p.s. from what I understand, offset micro lenses are fairly common in modern cameras, although they may be tuned differently.
 
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