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Kiril's web log
Sofia Breathes - visual arts 
Sunday, August 19, 2012, 09:06 PM
I hope you don't mind me sharing few pictures from yesterday with the NEX-7 ad CZ 24/1.8. Great camera and superb lens.

This is the full gallery directly out of Lightroom (my captions in Cyrillic I hope no one minds)
Sofia Breathes Gallery

and few shots to entice interest

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How to use remote flash with Sony NEX-5 (& 5n and 3 and c3) 
Thursday, December 29, 2011, 10:10 PM - Photography, Sony
A frequent problem that comes up with the Sony NEX cameras is the lack of standard flash hot shoe (the weird sockets on top of DSLR cameras). In practical terms this means the NEX is useless for photography training, studio photography and strobist photography.

I want to share here my simple solution to this problem. It is based on the following article and I have added a simple rubber band to hold all in one place for smooth experience.

First let me introduce you the basic building blocks

1. Seagull Remote Trigger SYK-5

2. Flash Trigger Remote Control - YongNuo CTR-301P

3. Hair rubber band

4. A Sony NEX camera with small detachable flash (this is the reason you are reading this article, no?)

5. A flash - I use YongNuo 560

6. A small black pouch e.g. the one that ships with Lensbaby does good work; flash pouches are too big and heavy

Here they are

Once you acquire all the building blocks it is fairly easy to figure out how to put them together.

The pouch is to cover the whole thing on the flash as to eliminate light from the build in flash on your final picture.

The magic settings for the SYK-5 are:

1. The switch should point to the eye icon (not flash). Note my picture is deceptive due to the shadow

2. The wheel should be turned all the way to the right (clockwise)

...and now the long awaited moment a remote flahs photo triggered from my NEX-5.

Some other observations:

1. The SYK-5 and the YongNuo trigger do not snap in the end position so the SYK-5 may slide off a bit and cause the system to stop working.

2. As the NEX-5 flash is raised you gain one of the NEX-5n and NEX-7 features - exposure is no longer previewed on screen allowing you to frame photos in poor light despite aggressive aperture and speed settings.

P.S. For the beginner - here is 101 of strobist lighting:

1. Switch to M mode

2. Check that speed is lower than 1/160 (or other lower than 1/160 - camera won't let you dial more when flash is attached - so another smart NEX feature)

3. Use aperture and flash power to get correct exposure - typically 3-4 attempts are needed to get it right. Correct exposure means photo looks good in preview + histogram does not show too much in the left or right end.
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Sony NEX-7 small review 
Sunday, December 11, 2011, 08:53 PM
As we all know the NEX-7 is late very very late. Sony have been doing all they can to get it in for the shopping season but no luck. Their last resort to share with the public the miracle they built was to give to Sony users chance to shoot with pre-production samples. In my case the Sony rep for Alpha in Bulgaria got in touch with me and offered me a sample NEX-7 for 1 week. Wow! This is what I call customer care! Way to go Sony!

I went to their office and pcked up a NEX-7 camera with 18-200 lens for a week. I made few hundred shots with it and made a small gallery on Pciasa to share. All photos are JPEGs from camera and uploaded in 100% size (use the magnifier icon to zoom in)

http://picasaweb.google.com/10893218305 ... Y25u5v3gQE

Some of you may be interested to know my impressions from the camera

The body design is very nice. I made comparison shots next to my NEX-5 (I used my trusted A700 + flash and softbox for this delicate job :-) ). As you can see the body design is very clean yet a lot of buttons and dials allow you to interact with all essential camera functions at a single touch. It is great continuation of the NEX design and despite it being a bit bigger then the 5 I think it is worth the compromise. Unlike Panasonic G1, GH1 etc. The NEX-7 remains quite thin, so the size is much smaller than DSLR

Onthe back you can see the tons of buttons and a new hinge mechanism for the screen that articulate form the middle of the camera, unlike NEX-5 that was attached to the top., This is great addition as it makes the camera much more discrete.

My first attempts with the NEX-7 were at a training in my office. I used the Zeiss Sonnar 90/2.8 for Contax G. Amazing lens starting at f2.8. It is much easier to use peaking with this lens and the NEX-7 than on the NEX-5. Peaking worked through the viewfinder too which I found very very handy.

white balance is a bit off but this you can blame on my skill not NEX-7 as I used manual balance

These were all iso 1600 shots. Colors and dynamic range seem quite fine thought he detail in JPEG is not fantastic.

The 10 fps advantage manifested itself on Saturday morning as I was making pancakes I asked my daughter to take few snaps

Both of these were shot with the kit lens in the shutter/speed priority continuous. Really amazing only slight click on the shutter ends up with 3 or 4 photos taken in an instant. As both shots were using avaialble light and the kit si not renown for wide aperture the NEX-7 used iso 1600 so detail is very very good but not excellent as one may expect on low iso.

Speaking of speed NEX-7 has another trick in the bag. There is no shutter lag. None it is all gone. It is faster than many DSLRs. The reason - there is only rear mechanical curtain. The consequences are two fold - taking the photo start when you press the button and the sound is dampened compared to NEX-5.

There had been a lot of discusison about the 18-55 kit possibly being totally useless on NEX-7. Well NO! The Kit lens 18-55 is performing very well on the NEX-7. Here are few cat shots. Do not forget you can see them in all their 24 MP glory on Picasa

Finally I had some spare time and put the Zeiss Planar 45/2 for Contax G on the camera. What an amazing lens. If you thought the photos above are ok in terms of sharpness you got to see the Zeiss - it is unbelievable

Here is link ot the photo on Picasa do zoom in to 100% http://picasaweb.google.com/10893218305 ... 5144312178

In the afternoon on that Saturday we wne tof ra walk in the park wiht my daughter (She is so nice for putting up with me). I kept the Zeiss Planar on -what a marvelous gem it is

The colors of NEX-7 reminded me so much about the Min0olta 5D I once had a loved.

...and again the Sonnar 90/2.8 amazingly sharp as well and fantastic defocus

As we all know one of the major advantages of the NEX-7 is its flash hotshoe. So using a couple of flashes (HVL-58AM + YN-56) and Radio trigger (Pixel Pawn wqith Sony & Nikon receiver) I made a couple snaps. Lens again was the Planar 45/2

... another random shot with the planar (This is the only snap I got as the store keeper got upset with my urge to take photos of merchandise)

At home I took out a soft box and an umbrella and my two flashes and asked my daughter to make a snap using the beyond decent 18-55

I mentioned that Sony handed me a 18-200 lens. This is acceptably big with the NEX-7 but is not really exciting to me in any way. Never the less I took ew of those cat shots to see if it is worthy. seems the lens will not disappoint those with inclination for super zooms or movies

On sunday I met my father at a local store. The detail NEX-7 with the planar is able to pull at f2 is just beyond belief and then the colors are fantastic - what is there enot to love

and then one more with the Sonar 90/2.8 @ 2.8. The cat is not in focus

Did I mention I love the colors? Well the 90/28 makes great colors too

I had to return the camera on Monday and here are my last shots. I wanted to see just how sharp the Zeiss Planar can get at f8

But then I had not tried the 16mm lens

and 16mm with the wide angle adapter for even more fun

oh can you believe this? the 16mm is tack sharp at f8 and quite sharp with the wide angle adapter!! I bet this combo beats the Tamron/Sony 11-18.

and more shots with the wide angle - lovely colors plenty of detail

Well the last photos were from the business park where Sony's office is and I gave back the NEX-7.

Over the week I took few hundred photos and tried as many as possible of the settings. The camera is using firmware 0.10 and evidently is not a production quality. Low iso shots were quite good and high iso remained very decent. At high iso there is loss of details, which to be honest is fully acceptable given the 24 Mega pixels. I think Sony need to work a bit on their firmware though. I had the following observations that Sony may consider improving:

1. There is no need for dedicated compensation button. The tri-navy gives direct access and the bottom button could be programmed to something more useful
2. There is no way to program the Shooting Mode function to some button or combination of button + wheel. The only option is to dedicate the center button on the navigation wheel to shooting mode which is quite suboptimal
3. The tri-navy opens tons of possibilities while Sony have made great use of it it may be possible to make couple of firmware upgrades to make it very fluent.
4. There are not user programmable modes like A700/A900
5. I could not find how to set custom max auto ISO - it stayed at 1600 most of the time but one evening went up to 6400 after playing wiht the camera for a while...strange

Before I wrap it up I would like to share few more shots I took the previous time Sony gave me this pre-rpoduction camera with the Zeiss 24/1.8 and Sony 30/3.5 - the album is here

http://picasaweb.google.com/10893218305 ... xurj4ZegSg

Unfortunately I do not have these full size as I shot RAW. I was able to extract the preview thumnails from the RAW files and here they are:

Zeiss 24/1.8

Sony 30/3.5

I also have a single shot with the fish eye adapter. It is noticeably softer than the wide angle though

...and if someone tells you m43 is any good in terms of dynamic range do not trust them. The sun is in the shot yet there is not much of black nor tons of white. I used the HDR at its maximum with the 30/3.5

My impression is that both the Zeiss 24/1.8 and the 30/3.5 are very sharp from their widest apertures.

I had a lot of joy with this camera and would love to have. I hope Sony can soon deliver it to stores so we all can enjoy this marvel of technology. I loved the following

1. 24 mega pixels! Yes it is worth to have it on the NEX-7
2. The image quality - unrivaled. This camera is just fantastic . I had never seen so much details from an APS-C. Colors are astonishing. It seems the Dynamic Range in RAW is amazing too (I do not have RAW software.). Again on colors this is the first Sony camera to remenice of the Minolta days - just look at forums people still cherish the Minolta 5d and 7D and try to force their Alphas in this mode. Well no more the NEX-7 does it with its "Deep" color setting! Thanks Sony!
3. The flash hot shoe is great addition to a NEX camera. Can we have a add-on module for the lower end models as well?
4. There is mode that allows decoupling of exposure from the display i.e. no exposure preview in the display or EVF. This allows you to shoot manual lens in bright daylight and as well allows you to shoot with flash in manual settings Great work Sony. Can you fix on all NEX and Alpha cameras starting with A300? We will not only love the cameras we will worship them then
5. There is an EVF and this is fantastic. Very good addition. there has not been situation where the NEX-5 display prvented me from taking a photo. On the contrary it allowed me much more, but sometimes a viewfinder is just that much better. The NEX-7 EVf is quite big and for first time I like composing using a viewfinder - on A700 it somehow felt crammed and unconfy so I tried to frame photos with my eyes and than hastily mimic this in the viewfinder. With NEX-7 I prefer the viewfinder. Great Job!
6. Speed - this camera is blazing fast. Virtually no shutter lag. AF is ultra fast with the kit and 16mm and a bit slow with the dark 18-200 at 200 and f6.3
7. Unobtrusive - the new screen hinge mechanism and dampened shutter sound make the NEX-7 very discrete.
8. Last but not least there are tons of useful buttons and the tri navy that for all practical reasons make the NEX-7 the easiest camera to use made to date - no DSLR comes closer.

Looking forward to seeing NEX-7 in stores!
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How to use the RabbitMQ user-id validation 
Saturday, November 19, 2011, 11:47 PM
I have not been posting anything in a while. But here it is a new post.

What caught my attenton is a simple thing - how to secure communicaitons between two apps leveraging messaging communicaiton over RabbitMQ. I found out that Rabbit MQ has an extension to the AMQP protocol Validated User ID that is supposed to serve this goal.

Yet how does it work? At first reading it does not make any sense. Sender needs to supply something ...when we actually want the recipient to be able to verify the sender identity...how so?

Well it turned out quite simple:

1. Sender needs to explicitly say they want thewir message authenticated i.e. not anonymous by providing their identity in the message properties
2. RabbitMQ makes sure the user id is not forged
3. Recipient may as desired verify that the user name of the ender application matches its expectations

Below is an example of how all this works. The application tries to send 3 messages a forged one that results in exception, an anonymous message and an authenticated messsage. There is also a small recipient side that ilustrates how to verify the user identity.

To use the sample one needs locally deployed RabbitMQ with default security i.e. guest/guest is admin. The sample is written in Python 2.7 and uses Pika 0.9.5


import pika
import sys

connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))

channel = connection.channel()


print "try forged message"
  # This does not go through as the user is forged
  channel.basic_publish(exchange='', routing_key='hello',body='Forged Message', 
except Exception as e:
  print "Cannot publish forged message"
  print e

#Get new channel and try good message with out forged id
channel = connection.channel()

print "try anonymous message"
  #This should go through as we pass the correct user
  channel.basic_publish(exchange='', routing_key='hello',body='anonymous Message')
  print "published anonymous message"
except Exception as e:
  print "Cannot publish anonymous message"
  print e

print "try authenticated message"
  #This should go through as we pass the correct user
  channel.basic_publish(exchange='', routing_key='hello',body='authenticated Message', 
  print "published authenticated message"
except Exception as e:
  print "Cannot publish authenticated message"
  print e

print "Listening..."
def on_receive(ch, method, properties, body):
  print "Received: %r" % (body,) 
  if properties.user_id is None:
    print "Ignore anonymous message"
  #At this point we can check if we trust this authenticated user... 
  print "Received from user: %r" % properties.user_id

channel.basic_consume(on_receive, queue='hello',no_ack=True)



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A kick in the right direction 
Friday, October 12, 2007, 11:28 PM - CMMI, CMMI Implementation
I am just back from Moldova where we conducted the initial meetings of the Moldovian IT Mark program of ESI Center Bulgaria. The IT Mark service is an interesting program that helps small companies get on the road of process improvement.

Chisinau is a nice city with strong European flavor. I have been able to take some pictures you can see themby clicking on the link below. If you happen to go to Moldova do try their wine it is like no other and is quite cheap.

Click here to go to Picasa…

I will try to drop few lines about IT Mark later when I have some spare time.

Meanwhile you can look as well at my pics from Yerevan Armenia where I lead an Intro to CMMI training in June 2007.


Also note there will be an Introduction to CMMI training in Sofia, Bulgaria at the end of this monnth or early in November. Please contact ESI Center Bulgaria to get more info and sign up.

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