Topic: Sensorium Dei

[Michael]

Cos è quello?

[Muffin]

That's a statue of an iranian hero, from the Museum of Handicrafts.
A few days ago there was a holiday, comemoration of another iranian her/martyr. Details are scarce because I couldn't find anyone who was able to describe it.
I visited a holy shrine on this occasion, they sand and performed a ritual dance, hitting themselves on the shoulder with that "whip".

I will post more pictures and videos when I get decent internet.

[Jahn]

Hi Rudi,
you are a great photographer, have you ever considered to make your photos public!?

I have uploaded a first batch of 22 pictures to ImageVortex - they have a decent deal with a 70% commission for standard photos. You can price the photos in a range between USD 20-300. Fees over USD 100 can be payed via PayPal or bank wire. I have no experience yet of it all, this because they have not yet approved my upload. But I will keep you updated.

The first batch of photos was a mix from me, my daughter and my sons fianceé.

 .~
 jm

[Nichi]

Hi Rudi,
you are a great photographer,

I agree!

That's something about the self-flagellation. I shouldn't be surprised, but I was.

[Michael]

Self-flagellation is a big thing with the Shia Muslims - they do it in huge groups also, while marching through the streets.

Love to see some more pics Rudi. Beautiful stone inlay work on that masjid.

[Muffin]

This too is Iran.

[Michael]

Amazing! Is this you up in the snow Rudi? It looks very cold. Great photography!

[Jennifer-]

I long for snow and frozen lands.. thank you for sharing your travels! Its good to see its not all work and some play

[Taimyr]

I know someone who wouldn't say no to a cold breeze and a little bit of snow.

[Michael]

Rudi, do you take photos in RAW then convert to JPG, or take in JPG from the start. I have found there is no file-size advantage to taking in RAW then converting to JPG, so unless I want to print in RAW, or convert to a very large TIFF, I feel I may as well stay with JPG. As mostly my interest is screen, I may as well stick with JPG.

Second question. Nico, who we met in Delhi, always uses AV setting, where he manually sets the shutter speed (I think). I don't know how to use that feature. Do you have a rule of thumb for manually changing the shutter speed?

Actually most of the pictures are taking by Julie, and she has little patience for using the half-pressure to refine focus. I usually get her to use a setting which constantly focuses, using more battery power, but that doesn't seem to be a problem with our camera's battery.

[Muffin]

I always shoot in JPG on the highest resolution and quality. It produces a 5-6 MB file, which has enough details to have a decent print from it or display it on screen. RAW is useful when you want to do post-production and want every pixel to be perfect. Basically only useful if you want your picture to appear on the cover of some fashion magazine, and even then they have enough photoshop skills to make your jpg picture pixel-perfect

About the second question, I don't know from the top of my head what the AV settings does, it seems like it's related with exposure compensation, not with shutter speed. 99% of the times I shoot full manual, where i set both the aperture and the speed. I try to shoot alwasy at the lowest speed possible to prevent blur. Blur can be caused by the motion of your hands when you press the button, or moving subjects. In sports you want very fast shutter speeds. Anything below 1/100 s will likely cause bluring, unless you have a VR lens. With VR lenses you can go up to 1/30 - 1/50. Higher then that and you need a tripod and still subjects. This means that I have very high aperture most of the time, affecting the field of depth.
You use lower apertures for landscapes or when you want to have more of the picture in focus, but you sacrifice the exposure time.

It's a game of balance.

[Michael]

Manual is too complex for me. I checked the manual - Av is setting the Aperture value, and Tv stands for Time value.

I can choose either, and the camera will adjust the appropriate other. So is it better to manually set the Aperture or Shutter speed? (I couldn't do both)

I understand the shutter speed is good for hand held, but what exactly does the Aperture value affect as far as the picture result is concerned? Why not maximum Aperture all the time?

[Taimyr]

The bigger the aperture value, the smaller is the actual aperture. With a biggest aperture (with smallest aperture value - for an example 2.8 ) you get more artistic images, where the objects in background or foreground are not in focus. Sometimes you need a bigger aperture when the light is low, and when it's very bright sunlight, you need small aperture, because otherwise the image will be overexposed.

Yes, a game of balance. ISO value is quite important too. In bright daylight 80-200 is ok, 400 and higher is good for more dim light. But the higher ISO is the more noise you get (the grainyness).

I can choose either, and the camera will adjust the appropriate other. So is it better to manually set the Aperture or Shutter speed? (I couldn't do both)

I understand the shutter speed is good for hand held, but what exactly does the Aperture value affect as far as the picture result is concerned? Why not maximum Aperture all the time?

[Muffin]

Manual is too complex for me. I checked the manual - Av is setting the Aperture value, and Tv stands for Time value.

That's different from Nikon, I have A for aperture, S for shutter and P for programmed.

I can choose either, and the camera will adjust the appropriate other. So is it better to manually set the Aperture or Shutter speed? (I couldn't do both)

Again, it depends on what you want to achieve, if you see that your subjects are moving and they are blurred, then use Tv, where you set the time value to low, and the camera will chose the right aperture to get a good exposure.
If you see that not all the subjects are in focus and you want them to be, then use A and set the aperture value higher (until you get the desired depth of field). The camera will set the exposure time, most likely to longer exposure time to compensate for the higher aperture.

Both aperture and shutter speeds control the exposure, and they complement each other. You can get the same exposure with different sets of values. By doubling the aperture you let twice as more light reach the lens, therefore you need half the time the shutter is open. Reducing the aperture reduces the amount of light that enters, so you need to keep the shutter open for longer.

Additionally, aperture affects depth of field (see Taimi's description), shutter speed affects nothing, but with longer speeds it's harder to "catch the insant" (if you try to get a car moving at 50mph at a shutter speed of 0/10 second, the car will be blurred, no matter what the aperture you use).

Re, aperture and depth of field, you could take a look at the image below:
I focused on the whip of the last man (closest to me) and used a very high aperture (f/1.4). Had I used smaller aperture(f/3.5) the second man would have been in focus too, creating a less striking effect. It's important to note that depth of field depends also on how far the subjects are from you. The farther the subject the bigger the depth of field, so if you focus on a person 50m from you, you will get everything in focus around them, regardless of the aperture. Had these men been farther, I could not have taken the same picture.

[Michael]

Thanks Rudi and Taimi - that gives me something to experiment with.