Artak Hambarian

Lives in Armenia Yerevan, Armenia
Works as a Professor
Joined on Jan 3, 2009
About me:

Architecture, Energy, Environment, Beauty

Comments

Total: 164, showing: 1 – 20
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On article Canon patent shows curved sensor design (97 comments in total)
In reply to:

AstroStan: This has prompted me to ponder the physics of vignette. It is possible to mathematically model the lens and imaging plane or semi-sphere then compare that to real-world results (e.g. "flat field" frame). There are 4 primary components of photon-flux per area attenuation:

1) aperture transmission. This varies geometrically with angle of incidence. e.g. circular at perpendicular and a decreasing area ellipse with increasing angle of incidence,

2) geometrical distortions of the lens. Pincushion or barrel, etc. distortions change the flux per area (measured at the plane or semi-sphere).

3) geometry of the focal plane / semi-sphere / bent-plane (etc.).

4) pixel angular attenuation due to cicuit structures and/or micro lenses.

Issues 1-3 are not a simple calculation but the basic geometry is not that difficult. Issue 4 cannot be predicted without insider knowledge. But it can be measured indirectly by solving 1-3 and comparing to flat-image.

I may give it a go. Anyone else?

Stan

OK I see, but spherical sensor automatically address number 4 too, with the same projection token. If I understand correctly, you mean that incidence under angle make problems with all the light reaching the p-n-junction plane or close to it.

Link | Posted on Dec 3, 2016 at 21:31 UTC
On article Canon patent shows curved sensor design (97 comments in total)
In reply to:

AstroStan: This has prompted me to ponder the physics of vignette. It is possible to mathematically model the lens and imaging plane or semi-sphere then compare that to real-world results (e.g. "flat field" frame). There are 4 primary components of photon-flux per area attenuation:

1) aperture transmission. This varies geometrically with angle of incidence. e.g. circular at perpendicular and a decreasing area ellipse with increasing angle of incidence,

2) geometrical distortions of the lens. Pincushion or barrel, etc. distortions change the flux per area (measured at the plane or semi-sphere).

3) geometry of the focal plane / semi-sphere / bent-plane (etc.).

4) pixel angular attenuation due to cicuit structures and/or micro lenses.

Issues 1-3 are not a simple calculation but the basic geometry is not that difficult. Issue 4 cannot be predicted without insider knowledge. But it can be measured indirectly by solving 1-3 and comparing to flat-image.

I may give it a go. Anyone else?

Stan

Number 4 is very similar to sun tracking solar panel vs. fixed. Geometry is very simple - the cosine of the projection.

Link | Posted on Dec 3, 2016 at 20:34 UTC
On article Canon patent shows curved sensor design (97 comments in total)

Let's look a bit, just a bit further future. No doubt spherical sensors should be the main technology. As well as the Foveon type sensors. I mean the combination of both. Just wait a few more years... Whatever is the fixed cost of the R&D, it will pay back via advantage obtained in the market.

Link | Posted on Dec 3, 2016 at 20:32 UTC as 12th comment
On article Slik Lite tripods feature built-in LED lights (46 comments in total)
In reply to:

entoman: Oh no, how did we ever manage before!

What's next on the list - an LCD panel indicating the current height of the tripod and the number of leg sections unfolded?

If you think, that is just a joke, entoman, just wait a few years...

Link | Posted on Dec 1, 2016 at 21:37 UTC
On article Slik Lite tripods feature built-in LED lights (46 comments in total)
In reply to:

Melchiorum: I have to charge/change batteries on my camera, my two flashes, my phone, my video light, my radio mic, my gimbal... Yeah, charging my freaking tripod too is just what I was missing!

You do not have to if you do not need to.

Link | Posted on Dec 1, 2016 at 21:33 UTC
On article Slik Lite tripods feature built-in LED lights (46 comments in total)

Clever.

Link | Posted on Dec 1, 2016 at 21:32 UTC as 17th comment
On article Manfrotto launches stylish Windsor Collection bags (57 comments in total)
In reply to:

Scottelly: It amazes me they say the backpack can handle a camera with a big lens and two extra lenses. I have three DSLR style cameras in my backpack, and each one has a lens on it (one lens is a 100-300mm and one is a big wide-angle lens). I also keep my tripod INSIDE my backpack, with the cameras and lenses. I have lots of other stuff in that backpack too. I carry my 13" MacBook Air with my power supply in the backpack too.

The funny thing is that my backpack is not a big one. It's not a small one either, but it doesn't even compare in size with the big backpack my photographer friend has.

Why can't this new backpack from Manfrotto carry more stuff?

Thank you Scottelly! I am looking for a backpack that can accommodate a tripod. Can I ask the models of your backpack and the tripod? I consider a flat tripod, and Fstop gear backpack that may allow carying it inside, next to ICU.

Link | Posted on Nov 21, 2016 at 22:12 UTC

Any bag with a big flap might be good for transporting gear from A to B, but not for photography itself - holding up the flap is very inconvenient when say taking out the camera or changing a lens. At least there should be a top zippered opening. Sorry Think Tank Photo for all Retrospective series and thank you for UD and especially for Suburban Disguise top opening, despite of still having a big flap with a big pocket.

Link | Posted on Nov 5, 2016 at 06:08 UTC as 16th comment

93% efficiency... I guess it should be the value for the CRI - color rendering index. Otherwise how come this high efficient LED-s managed avoiding the Nobel prize?

Link | Posted on Sep 3, 2016 at 21:35 UTC as 11th comment
On article Throwback Thursday: the Samsung NV10 (75 comments in total)

What is happening with the Samsung camera division nowadays? Any insights? Piti...

Link | Posted on Sep 1, 2016 at 18:48 UTC as 36th comment
In reply to:

Banhmi: Interesting, but ultimately, this is going to be another extremely niche product.

I still feel strongly that the right product for most photogs isn't a 'serious camera smartphone' but a 'serious camera with Android'. Imagine if paying, say, $300 premium on the Canon 5D IV got you a 'Canon 5D IV Android' -- connected to your Gmail account, Flickr App, etc? Maybe this is a stretch for Canon, but surely Sony, who already makes smartphones, could throw a touchscreen on an a7III and let me do basic post-processing and photo-sharing right on the back of my camera?

Totally agree. I think that is inevitable!

Link | Posted on Sep 1, 2016 at 06:43 UTC
In reply to:

Artak Hambarian: Guys, does anyone know of any video editor capable of white balance management, that is also not expensive or free?
BTW my most used editor for stills is the ACDSee Ultimate, and I use PS CS6 for pano stitching.

Thank you Pgb!

Link | Posted on Aug 27, 2016 at 22:05 UTC

Guys, does anyone know of any video editor capable of white balance management, that is also not expensive or free?
BTW my most used editor for stills is the ACDSee Ultimate, and I use PS CS6 for pano stitching.

Link | Posted on Aug 24, 2016 at 16:12 UTC as 85th comment | 3 replies

High popularity of this device or its modification is inevitable. Unlike Google glasses.

Link | Posted on Jul 22, 2016 at 21:42 UTC as 69th comment
On article Medium-format mirrorless: Hasselblad unveils X1D (1188 comments in total)

No need any more to buy Leica!

Link | Posted on Jun 22, 2016 at 19:30 UTC as 99th comment
On article Virtual Reality: It's not just for gamers anymore (140 comments in total)
In reply to:

Artak Hambarian: Current VR combining two challanges:
1. 3D, which faces non existance of good high res viewers, and I, as a photographer, care about this the most - I have been in stereophotography more than 30 years. I have done really stunning (for at least me and my friends and family) 3d macro and architectural shots that one can view over and over...
2. Interractive immersion via turning your head or by directing your sight. This is an entirely different beast, that in my opinion has some specific applications. I can see guided movies here.
I think these tasks should target different markets and shall be solved separately. E.g. the first task is relatively easy to solve by creating a 3d (stereo) digital viewer with really high resolution, e.g. 4-8 mp for each eye.
Later the audio related issues should be solved. BTW, its hard to see how could binocular effect be seemless when turning one's head.
I am waiting for the good 3d stills viewer, and not so much for the "interactive" experience.

Thanks for the link! Few more years? Well they will pass quickly anyway.

Link | Posted on Jun 7, 2016 at 21:00 UTC
On article Virtual Reality: It's not just for gamers anymore (140 comments in total)

Current VR combining two challanges:
1. 3D, which faces non existance of good high res viewers, and I, as a photographer, care about this the most - I have been in stereophotography more than 30 years. I have done really stunning (for at least me and my friends and family) 3d macro and architectural shots that one can view over and over...
2. Interractive immersion via turning your head or by directing your sight. This is an entirely different beast, that in my opinion has some specific applications. I can see guided movies here.
I think these tasks should target different markets and shall be solved separately. E.g. the first task is relatively easy to solve by creating a 3d (stereo) digital viewer with really high resolution, e.g. 4-8 mp for each eye.
Later the audio related issues should be solved. BTW, its hard to see how could binocular effect be seemless when turning one's head.
I am waiting for the good 3d stills viewer, and not so much for the "interactive" experience.

Link | Posted on Jun 7, 2016 at 04:24 UTC as 14th comment | 2 replies

Guys look at how good the new Novoflex tripod is with unique integrated leveling. This information to me is more important than the meaningless Leica talk. I need to investigate it!

Link | Posted on Jun 3, 2016 at 19:47 UTC as 4th comment

All contemporary VR sets look miserable from photography point of view. Including those capable of using 2.7K smartphone screens, which is the current top resolution. They are like VGA displays when there is 4K. Interestingly, technology easily allows, and I will be an early bird if a stereo electronic viewfinder appears that has at least same resolution as the a6300 (for each eye).

Link | Posted on May 31, 2016 at 20:25 UTC as 5th comment | 2 replies

Good that one more bag and tripod manufacturer makes this type of a bag. Except for smaller gear compartment compared to Lowepro Flipside 400 which I own, it has advantages. 1. removable gear compartment, 2. Laptop/tablet compartment, 3. Additional top compartment. However the molded plastic bottom, or some kind of water sealed bottom, that I have been waiting for, is not there.

Link | Posted on May 10, 2016 at 22:05 UTC as 16th comment
Total: 164, showing: 1 – 20
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