2010-06-27

Test Jablotron Album

Na trhu je řada digitálních alb, na kterých můžete prezentovat své obrázky bez nutnosti mít zapnutý počítač nebo laptop. V dnešní době je nutné zamyslet se důkladně nad funkčností tohoto přístroje. Máte v zásadě dvě varianty: koupit přístroj, který umí pouze prohlížet fotografie nebo koupit přenosné multimediální zařízení. Digitální album je obvykle levnější a má jednodušší ovládání. Můžete jej koupit i rodičům, kteří technice příliš nehoví a budou jej schopni ovládat. Na druhou stranu multimediální přehrávač (třeba iPad nebo tablet s Androidem) je mnohem univerzálnější. Ale zanechme úvah a podívejme se na elektronické album od firmy Jablotron.

Nikde na Internetu jsem nenalezl smysluplnou recenzi, která by popisovala kvalitu zobrazení fotografií, proto jsem se rozhodl napsat tento článek. Pokud si chcete přečíst obecný popis přístroje, podívejte se na následující stránky:
Já se budu soustředit zejména na kvalitu obrazovky. Obrazovka je pravděpodobně typu TN. Odpovídá tomu kvalita barev i pozorovací úhly. Pozorovací úhly považuji za dostatečné. TN obrazovka bude vždy citlivá a pohyb hlavou vertikálně. Nicméně u digitálního alba nelze předpokládat, že toto bude zásadní problém (u digitálního rámečku bych byl opatrnější). Horizontální posun pozorovatele změny barev nepřináší.

Čelní pohled

Boční pohled s minimální deformací barev

Horní pohled s výrazně světlejšími barvami

Spodní pohled s výrazně tmavými barvami

Druhý aspekt, na který jsem se soustředil je kvalita podání barev. Ta je z mého pohledu na hranici únosnosti (pokud očekáváte vysokou kvalitu). Zásadním problémem je podání teplých tónů. Zdá se, jako by červený kanál byl jaksi utlumen. Zatímco převáže modro-zelené pasáže jsou relativně dobře zobrazeny, tváře a jiné žluto-červené obrazce jsou velmi "vybledlé".
První snímek porovnává zobrazení pleťových barev na Apple iMac s H-IPS obrazovkou a na Albumu. I z pouhé fotografie je patrné špatné podání obličeje dítěte.


Tyto dva obrázky porovnávají obrazovku Apple iBook (kvalitní TN). Je patrný posun barev opět zejména u fasády domu.

Poslední obrázek je opět porovnání s Apple iMac (aplikace Aperture a Preview). Z fotografie je zcela patrný posun teplých pleťových barev. V tomto případě je celá fotografie značně vybledlá.

Takže pokud test shrneme, Jablotron Album prošlo. Nemá rozhodně výbornou, nicméně pokud potřebujete něco místo notebooku na prohlížení nafocených fotografií na dovolené nebo na ukazování fotografií na návštěvách, je to schůdné řešení. Překážkou spokojenému dlouhodobému používání může být a) citlivý povrch přístroje, který je náchylný na poškrábání b) velmi pomalé vykreslování náhledů, když se vracíte do náhledu sekvencí fotografií. Pokud jste fotograf nebo prostě očekáváte precizní podání barev, hledejte jinde.

2007-11-04

New iMac vs. "old" iMac

Few days ago I received new iMac 20". I's the cheapest version with 2.0GHz Core 2 Duo, 250GB HDD, etc. My iMac has 2GB of RAM. For almost a year I'm using last version of "old" iMac. So, this article is a brief comparison of main differences between them from my point of view. It's not a review, you could find dozens of them on the net.

Main differences:

  1. Display -- Greatest difference. New display is IMHO terrible. In comparison to old 20" iMac display this one has really very low viewing angles. Announced 160° is almost lie. I could move with my head up to 30 cm up or down without strong color change. Color change is noticeable also during horizontal movement of a head. This is huge difference. By the old iMac until you see the display, you see the picture in same colors. Now, you stand from the chair and colors are really inverted. It's like some really cheap ACER or BENQ LCD.
  2. Design and ergonomics -- Great, as always. Someone likes more new design, someone new. By all means new iMac is almost perfect -- nice, thin, silent, metallic. What I'm missing is magnetic gripping of the remote control. It was really smart and ergonomic. Fine is also easy replacement of RAM modules.
  3. New keyboard -- In one word, astonishing. Really great design, even better in reality than on pictures. But there is pretty low place around USB ports. If you have small Flash disc, it will be OK, but lager disc or USB devices will have problems. It is victory of design over ergonomics. Also keys are same as in MacBooks. I hope they are better than there, because on my MacBook some keys are shaking after one year of very intensive usage. Better is also placement of keys for starting Exposé and other MacOS X features. Applause...

Conclusion

New iMac is great, faster, maybe nicer, with great OS and keyboard, but it has a really great drawback - it's display. Originally I thought Apple is canceling 17" line and replacing it with 20" line. Now I see, that Apple used brand new and probably cheaper 20" LCD. It is really unfortunate move a I'm very surprised, that it is not mentioned in many "professional" reviews. Once again, drawback of the display is not its glossiness, but very low (especially vertical) viewing angle. I hope, that more expensive line of 20" iMacs has at least same display as the old ones.

From this reason I rejected to replace my older iMac with this new one. The gain of computation power was not adequate to the deprivation caused by the new display.

2007-05-13

3D Analyst + Intel Xeon = Mistake

I made model of flood in villages near Kyjov. On my desktop in office (Intel Pentium 4 3GHz HT, 1GB RAM, SATA HDD, nVidia GeForce 6200) it was running fine. Model contains some aerial imagery, raster with wather, vectors with villages, rivers, etc. Then I moved into VR lab and opened model in ArcView+3D Analyst on HP Workstation there. It was turn-based strategy, after every move with the scene was ArcScene for at least 15 seconds frozen. After removing rasters everything was all-right.

I discussed it with my colleague whis in working in company developing Ansys. Problem is probably in the HP Workstation. It's equiped with 2GB RAM, nVidia Quattro card etc. BUT it has also dual-core Intel Xeon processor. Xeon processors has only one bus for communication with memory and in case cores need huge amount of data (e.g. rasters), this bus is overloaded (cores are "fighting" for it). This causes lack of performance.

Possible solution is using version of Windows (or) other OS which allows to enable only one core for application.

If you have some experience of running ArcScene on single/dual-core machines, I'll happy to hear about it.

2007-04-03

VRScape review

Colleague from Millennium Gate Company provided me demo of VRML (Open Inventor) browser by VRCO - VRScape. I have tried some prepared models and also made few new. Browsing VRML is in VRScape easy. You must just create short project file which is loaded by VRScape. Example of such file is here:

Model ./data/office.wrl OFFICE
Translation 0 -30 0
Rotation -90 180 0
Pickable True
defaultlight on
  • First line loads VRML file. Model is keyword, follows path to the file and last part is link for setting further options.
  • Second and third line are setting scene into initial position.
  • Pickable True allows beter manipulation with the objects. If you enable "pickable" option, you coud rotate with the scene (with the object). This feature is useful if you want to examine some VRML object (car, head, ...)
I was disappointed with things. First one is control. You could choose between "walk" and "fly" mode. Walk allows to walk on some surfaces (table, floor, ...). During fly mode you are flying trough the scene. Suddenly in my case (CaveLib, Trackd and Flock of birds + Wanda) there was problem with changing the course of movement. I must turn in large circles. This is very uncomfortable. Moreover sometimes control starts jumping and it is almost useless.
Settings of the motion tracking are stored in CaveLib environment which is VRScape sharing with eg. vGeo, so problem must be in VRScape, not in the hardware or tracking drivers (vGeo works fine).

Second problem/feature is maximum size of the VMRL file with which you should work. I tried few files between 2-10 MB and they worked fine, but VRML around 80MB was pratically useless. Scene was redrawed every 3 seconds (Intel Xeon around 2GHz, nVidia Quattro, 2GB RAM, ...). I know, it's lage, but this lab is for serios work, not for gaming.

On the other side, great advantage of this product is possibility of colaboration -- see VRCO pages. Suddenly I dont's know any lab with same software, so I can't try it.

2007-03-06

Rhinoceros 4 Active Stereo Support - part 2

In previous post I spoke about bad active stereo support in Rhinoceros 4. In last days I received two mails from supports. First one was forwarded by Mr. Cilek from Rhino main display developer, second one from Czech Rhino support. Main developer briefly described settings and requirements for stereo, but it was useless. I have all requirements and correct settings, but it's still not working. Czech support frankly told me, that stereo support is in the beginnings. So, we must wait...

2007-03-04

Stereo multimedia player

I was searching for some good multimedia player supporting stereo output. The best one I have is 3Dtv.at Stereoscopic Player. It's simple and powerful. It's able to play stereo movies in almost all stereo formats:

  • interlaced (column, row,)
  • side by side,
  • over/under,
  • SIS Attachment
and it could convert them "on the fly" to your stereo format:
  • Dual Screen Output
  • NVIDIA Stereo Driver
  • StereoBright
  • Quad Buffered OpenGL
  • Sharp 3D Display
  • SIS Attachment
  • Side By Side
  • Over/Under
  • Row Interlaced
  • Column Interlaced
  • True Anaglyph Red - Blue
  • True Anaglyph Red - Green
  • Gray Anaglyph Red - Cyan
  • Gray Anaglyph Yellow - Blue
  • Half Color Anaglyph Red - Cyan
  • Half Color Anaglyph Yellow - Blue
  • Color Anaglyph Red - Cyan
  • Color Anaglyph Yellow - Blue
  • Optimized Anaglyph Red - Cyan
For many people with active projection (shutter glasses, stereo projections, ...) is interesting option "NVIDIA Stereo Driver" - send it to graphic card driver and you will see...

Program is payed, but free version works for five minutes, what is more than enough for testing. On the 3Dtv.at page you could find also nice sample HDTV stereo videos, some add-ons and plug-ins.

It's simple - choose type of the input and output and it's simply working...

2007-03-03

Stereo visualisation of 3D Studio MAX models in ArcScene

Minor function of ArcScene is ability to visualise simpler 3D Studio MAX models. Usually it's used for placing houses into terrain models, etc. But in case you are using ArcView with stereo projection, thanks to this function, you could use ArcView as stereo viewer for MAX models. Here is brief tutorial:

  1. In ArcCatalog create new point vector layer.
  2. In ArcMap start editing (toolbar editing) of this layer and add one point. Save. Quit.
  3. Finally in ArcScene open blank project, add this layer. You will see you one point in the middle of the screen.
  4. Click on point in layer toolbar below name of your layer, choose Properties, from roll-down menu choose 3D marker and pick file with your model. Confirm settings.
You could see in the middle of your screen you 3D Studio MAX model. In "View - Scene Properties" choose nice background, in "View - View Settings" enable stereo (previous post) and you have perfect free stereo viewer.

Suddenly, ArcScene has problems with complex models. Only models around 10MB works.