Nope, the 50mm F1.4 at F2.0 will be creamier than the Zeiss at 50mm F4.5! So please do try it especially in daylight.

achew, not if there are bright highlights, then the 50mm at F2.0 will be less distracting. Lemme see if I can get some examples later!

Sigma 17-35mm F2.8-4 EX at 17mm F2.8 ISO200 with DRO Level 5 on a900. Camni baru Ultra Wide Angle punya gambar!

This post has been edited by albnok: Apr 6 2009, 04:21 PM

nowmodelling: It's in Ipoh. Nothing fancy, just a random torn-down shophouse.

ryzan76: When you see bright daylight, just turn on DRO Level 5. It's that easy. Screw HDR, most people do not know how to do it properly. DRO looks better!

This post has been edited by albnok: Apr 6 2009, 05:46 PM

SHOfrE3zE: Turn off Long Exp NR if you are shooting fireworks. Otherwise no need to turn it off.

High ISO NR, up to you - it kicks in at ISO1600 and above.

Wonka: All lenses with DT, DC or DiII in the name are APS-C only. The Sony Carl Zeiss 16-80mm F3.5-4.5 DT is such a lens.

Kit lens replacement for APS-C:

Carl Zeiss 16-80mm F3.5-4.5 DT (sharp, great colors and contrast)
Sony 16-105mm F3.5-5.6 DT (good range)
Sony 18-250mm F3.5-6.3 DT (good range)
Sigma 18-50mm F2.8 DC Macro (good close range plus F2.8 at 50mm)
Sigma 17-70mm F2.8-4.5 DC Macro (amazing macro for a standard zoom lens)
Tamron 17-50mm F2.8 DiII (F2.8 at 50mm)
Tamron 18-200mm F3.5-6.3 DiII (under RM1000!)

Personally I love the Sigma 17-70mm; it's a great fun lens due to the minimum focus distance.

I have a new flash!

hokc77, nice minibike shot!

SpOOkY, beats me - the exposure with flash was darker though. I don't know why. So some masking was required and as you can see I didn't do such a good job around the F42's flare.

v1rtual, the one on Thursday is on because ieR only arrives in KL on that day... been trying to get in contact with the organizer to ask if he wants to push the Wednesday one to Thursday also but he's not picking up his phone.

chiggy, get an adapter - the auto-thyristor modes on it are excellent! It even covers wide enough for a fisheye, surprisingly!



Sony Carl Zeiss 135mm F1.8 on a900 at F2.5.

ament, barger you, every girl also you sapu already!

8mm baru wide enough.



chiggy, auto-thyristor is the A1/A2/A3 mode - it has a sensor that detects the light reflected from the subject and cuts off the light when it senses it has had enough. In a way, it's like TTL but without any connections, but you must dial in the correct A setting for the aperture and ISO you're using.

v1rtual, both TTs are at Restoran Kg. Pandan, Jalan Yap Kwan Seng, off KLCC.

achew, I love #3!

signither: RM250. But you need to get the Sony to ISO hotshoe adapter if you want to use it as a on-camera flash (which is kinda pointless, because you can't bounce it) but I bought it since my A900 didn't have a pop-up flash and I wanted something compact for the clubs. Direct flash is alright if you know how to balance your ambient light (or do other effects with it!)

The cool thing about it though, is it can work as a wireless slave flash ignoring the pre-flash and work in Auto-Thyristor mode or Manual mode. So if the camera's pop up flash is in standard fill flash with pre-flash, the Sunpak can be triggered, and can be auto (like TTL) or manual power.

ament, I still like the Sigma 12-24mm F4.5-5.6 EX DG lah.

signither, the PF20XD only has 2 pins (1 on the side, 1 in the middle). So it has no TTL functionality and therefore is not a Canon-mount flash or a Nikon-mount flash - it's purely a universal ISO hotshoe flash.

Yes, it will work as a wireless slave but the body must be in normal fill flash, not wireless flash mode. I'll bring it for Thursday's TT and I have not tested it with a pop-up flash in wireless, though...

I've always wondered why the Minolta/Sony 135mm F2.8/T4.5 Smooth Transition Focus (STF) lens was manual focus only. So, I decided to test this theory by mounting it on my Minolta X300!

First I had to keep the aperture blades open, so I stuck some tape to hold the lever in place. As you can see, inside the lens, the edges are gradually darker due to the apodization filter inside.


Then, I positioned the lens and body together, with an eraser and CF card holder to keep the lens from rolling.


I looked through it, and it confirmed my theory - the upper half and lower half of the split prism would never match due to the gradual darkening coming from opposite ends!

This is due to the apodization filter which darkens the periphery of the lens (giving the beautiful bokeh that the STF possesses.) Obviously, the top half is looking through the right side of the lens while the bottom half is looking through the left side of the lens.

Phase-detect auto-focus works in a very similiar way to a split-prism on a manual-focus viewfinder - it looks at the subject from two opposite ends of the lens and drives the lens to focus so that the two images are aligned.

If you've tried a darker lens on a split-prism viewfinder, you might find that one of the two halves will be darker than the other - this just means that your eye is not centered in the viewfinder, so you need to move slightly to your left or right until the brightness matches. However, you would never see a gradient darkening with a non-STF lens!


This is what an out-of-focus picture looks like through a split-prism viewfinder. You need to focus the lens by turning it until the top and bottom halves of the split-prism align.

This will be easiest to focus on vertical lines and almost impossible with horizontal lines!


I then tried to see if the gradient darkening happened with a normal lens by moving the camera left and right of the viewfinder - it didn't. Instead, one half got uniformly darker than the other.

Of course, on an phase-detect auto-focus system, the 'eye' never actually moves left and right, and it's always aligned on the center.

So how does a regular phase-detect auto-focus system work?

Each AF sensor has two lines of sensors - one line of CCDs that sees the upper half, one line of CCDs that sees the lower half. It can see how 'far' each line is from each other, and know immediately where to focus the lens.

So, the lens is driven to the focus point, and then the camera looks at the two halves again and makes micro adjustments.

Cross-type sensors

Cross-type sensors are just a pair of line sensors at 90 degrees from each other, so it is sensitive to both horizontal and vertical detail.

So why doesn't the STF work with auto-focus?

As you saw earlier, the top and bottom halves have a gradual darkening coming from opposite ends. So, even if the object was in focus, the CCDs will never say it's a match!

A way that might've worked is that the camera knows that the STF is being used, and compensates for the gradual darkening when comparing what the two CCDs see.

My guess is that the gradual darkening differs with focus range and aperture setting, so it might've been too complicated for Minolta to program into the bodies when they first released the STF.

So what's the big deal about the STF anyway?


Sony 135mm F2.8/T4.5 STF at T4.5. Note how the out-of-focus highlights are circles with gradually darker edges.


Minolta 50mm F1.4 at F1.4 (cropped to give the same angle of view.) Note how the out-of-focus highlights have ugly, distracting borders (especially at the bottom of the picture.) These borders are called bright-line bokeh.


Here is another example also from the 50mm F1.4. The lights on top really should be out of focus and thus not distracting, but they pop out of the background!

Of course, the 50mm F1.4 and Minolta 50mm F1.7 are very poor examples - a lot of old Minolta zooms and primes have much better rendition of out-of-focus highlights.

I believe DigitalsMania has it - can't seem to find it but it's the same but apparently it comes with an adapter.

There is one account of an Alpha user who has it here:
http://www.alphanatics.com/viewtopic.php?f=6&t=5025

Ah thanks for finding it!

chiggy, this would be good for you - with the adapter which is quite expensive otherwise, you can use the Sunpak PF20XD on your Alpha:

http://www.lelong.com.my/Auc/List/2009-04D...0_A700_A900.htm

Sony flashes are named after their guide number in meters at maximum zoom.

F36 = 36 meters at ISO100 zoomed to 85mm maximum
F56 = 56 meters at ISO100 zoomed to 85mm maximum
F42 = 42 meters at ISO100 zoomed to 105mm maximum
F58 = 58 meters at ISO100 zoomed to 105mm maximum

Then, you need to divide it by your F-stop.

So if your aperture is F5.6, then the F56 at F5.6 will only reach a maximum of 10 meters at ISO100, 85mm zoom.

You can double the flash distance by increasing ISO by 2 stops - so, at ISO400, the F56 at F5.6 will reach 20 meters at 85mm zoom.

chiggy, yes (though, it's not quite as useful other than it being a lot higher than your pop-up flash.) That said direct flash is the way to go over large distances.

Radeon: no, Sony's guide numbers are measured in meters.

http://www.mhohner.de/sony-minolta/flashes.php

amd_hardcore, you can order it at a Sony Style.

Kul | Mo0, the F36 only turns up and down but not left and right which the F42 does. It also does not have a Test button or manual power setting.

amd_hardcore, I lost my A100 eyepiece before. It was under RM50, don't remember exactly how much though.

millenia3000, come for the TT this Thursday!


Teh Tarik Session This Thursday

What: "Welcome ieR to KL" TT and a little flash workshop!
When: 7:30pm onwards Thursday 9th April 2009
How Much: Free lah but buy your own teh o ais
Where: Restoran Kg. Pandan, Jalan Yap Kwan Seng, nearby KLCC LRT station.

http://wikimapia.org/#lat=3.1626591&lon=10...=17&l=0&m=h&v=2

By public transport, take the Kelana Jaya LRT line to KLCC station. Go up the stairs to the bus stop and hop on any bus that goes to Titiwangsa (comes frequently), it will pass by Jalan Yap Kwan Seng. You will see Restoran Kg. Pandan quite easily but it's near the end of the road.

Who's coming:
1. albnok
2. ieR
3. aming
4. Boon3
5. iGeorge
6. @bout_@perture
7. Photomaniac
8. meteorax
9. azmanhizam
10. dingenius3
11. marushin
12. vandechrome
13.
14.
15.
16.
17.
18.
19.
20.

This post has been edited by albnok: Apr 7 2009, 04:26 PM

After college la dude. TT sessions can go until quite late wan. Well some of us have work and are coming after work LOL!

I work from 9-6pm and I am probably older than you. So I should be more tired out than you young college farts! Issh budak sekarang senang pancit.

SHOfrE3zE, you might want to tone done the sharpening. DRO does affect RAW - it does not enhance the shadows, you still need to do Shadow Fill yourself, but it does cause your camera to pick a faster shutter speed to keep the highlights from being blown. So it will be noisier because it is slightly underexposed compared to when DRO is off.

Kul | Mo0: You can leave around 9:45pm, walk to KLCC, hop on the LRT to Kelana Jaya and reach there around 10:30pm. That should be a good time to grab a cab or bus to Damansara Utama. I take the bus from KL Sentral to One Utama and it passes by DU.

You'll want to turn off DRO for shots where you want it to retain some overall scene contrast. Come for the TT I'll show you what I mean. DRO is best turned off in the evening and night unless you're using flash.

This is what the A700/A900 can do with DRO Level 5:




(This picture has had some minor dodging in addition.)





I think you know by now that if you usually shoot in such sunny conditions without DRO, the trees would be nearly black!

You can do the same thing with RAW or a HDR program. Really this is what HDR is meant to do, not those cartoony-looking pictures!

This post has been edited by albnok: Apr 8 2009, 12:12 AM