Tuesday, May 11, 2010

Climbing Mt Sinabung


Gunung Sinabung from Danau Lau Kawar. Silly me didn't take a photo of the peak from a far. Photo by ahmad riza h nst. copyleft



Terrain from Google at www.peakware.com. On the basis of the terrain map from peakware, Danau Lau Kawar is at about 1400m, and the peak is at 2450m. The hike/climb was about 1km vertically! We took 3.5 hours to get up and 3.5 hours to come down.

Where we stayed

Wisma Sunrise View
Jl. Kaliaga no.5
Berastagi North Sumatera
Indonesia
Email: romanto_karo2@yahoo.co.id



Earth Quake
Just a side note, as we were leaving Danau Toba to go to Medan, an magnitude 7.2 earth quake shook Northern Sumatra/Aceh Province near Meulaboh at 12.59pm local time. We were in a bus and did not feel the quake at all!

Monday, April 26, 2010

50mm Nikkors Part II

OK, some real life photos instead of test shots.

AFD 50mm f/1.8 @ f/2.5. Ireland 2008.



AFD 50mm f/1.8 @ f/2. Ireland 2008.


AFS 50mm f/1.4G @ f/1.4. Singapore 2010.


AFS 50mm f/1.4G @ f/1.4. Singapore 2010.




50mm Nikkors Part I

What is a normal or standard lens?

My love for the standard lens started in 1979, when my pal Ngei was kind enough to let me go out and learn photography with him on his (then) state-of-the-art Canon AE-1 with FD 50mm f/1.8 S.C. and Speedlight 155D. For about 2 years, that was all that we had to play with... but the 50mm taught me lots about photography.

Since then I have had a large number of Nikkor 50mm lenses, in succession, bought (and mostly sold): Ai 50mm f/1.4 (used), then AiS 50mm f/1.4 (used), AF 50mm f/1.8, AF 50mm f/1.4 (used), Nippon Kogaku 50mm f/1.4 Nikkor-S (used), Ai 50mm f/2 (used), AiS 50mm f/1.8 (used), AF 50mm f/1.8D (subject of this write-up), and AFS 50mm f/1.4G (companion to this write-up).

AF 50mm f/1.8D, photographed on the morning before it was sold, sob sob. Sold 23 April 2010.

My 50mm arsenal, clockwise from back: AFS 50mm f/1.4G, Ai 50mm f/2, AF 50mm f/1.8D and Nippon Kogaku 50mm f/1.4 Nikkor-S.

As this was my last chance to do an unscientific test, I grabbed the two AF 50mm and my D300 and did a series of shots, to see if the nearly 4 times price difference was really worth it.

The test
It was raining.... 6pm, just outside my flat. Grab and shot. Was planning on a tripod mounted test, with the other two 50mm in tow, using D60... but this will have to do.

AFS 50 vs AFD50/1.8 at f/1.4 and f/1.8


AFS 50 vs AFD50/1.8 at f/1.8 and f/2


AFS 50 vs AFD50/1.8 at f/2 and f/2.8


AFS 50 vs AFD50/1.8 at f/2.8 and f/4


AFS 50 vs AFD50/1.8 at f/4 and f/5.6


AFS 50 vs AFD50/1.8 at f/5.6 and f/8


Conclusions
  1. The AFS 50mm f/1.4G was distinctly soft at f/1.4, improving at f/2 and by f/4 reached excellent performance, improving only slightly at f/5.6 and f/8.
  2. The AFD 50mm f/1.8 was, surprisingly, quite sharp and with good contrast at f/1.8, and showed the same trend as the AFS 50mm f/1.4G lens.
  3. Under the test condition, photographs produced by the 2 lenses were virtually indistinguishable.
Of course under different conditions others have reported the AFS is slightly sharper, with less CA, etc. That aside, the difference really wasn't worth the price difference.

The AFD 50mm f/1.8 is a real steal for its price.

Friday, April 9, 2010

AF 80-200mm f/2.8D revisited

Last weekend I had a chance to field test this lens while my daughter had a birthday party at the Bottle Tree Park, Singapore.


Spotted this kid trying to play with water while mummy bathed him. Took 2 shots, one at shorter focal length and this one. Nice...



While waiting for lunch took a few quick shots with intermediate distance subject and far background, to check out the bokeh of this lens. Not bad - careful composition can give pretty nice background blur. Satisfied.


One of the guru's at Clubsnap forum likes to shot cats. Well, there was a cat, so I took a few shots. Those shot at f/2.8 had nose and whiskers out-of-focus (OOF) when eyes are sharp. A quick check on the LCD meant using f/4 instead. Nice and sharp.

Other impressions:
  1. Lens not too heavy for prolonged use, maybe not for backpacking or mountaining, but certainly manageable for usual travel use.
  2. Sharpness in practical use at f/2.8 is good enough, unless there is side-by-side comparison I doubt if it is clear that there is some lost of sharpness.
Overall happy with this lens.

See earlier posting testing at the window.

Checking out VR

I belong to the old school - tug your tummy, practice good handling and shot. I probably have 85% success rate with 1/15s, and 50% at 1/8s. So I never did give VR much or a thought even though I had 2 VR lenses in my bag (AFS 105mm f/2.8G VR and AFS DX 18-105mm f/3.5-5.6G VR). In fact I tended to bring along my AFS DX 18-70mm f/3.5-4.5G for the slightly faster maximum aperture at 70mm, or put the AFS DX 35mm f/1.8G or AFS 50mm f/1.4G in the bag whenever I envisaged low light photography.

Well, today I had a chance to pick up an AFS DX 18-55mm f/3.5-5.6G VR for slightly better than spare change. Why not? Even though I already have the older AFS DX 18-55mm f/3.5-5.6G – the D50 kit lens that I bought second hand for $150.

AFS DX 18-55mm f/3.5-5.6G VR.

So I did a short series of test as I picked up the lens, and while waiting for wify to pick up marketing stuff.

Here goes.

Available light, Nikon D60, ISO400, handheld, aperture priority or shutter priority as indicated.

First of window test, cropped, VR on and off as per indicated, Aperture Priority.


Some gain in sharpness even at 1/15 is visible, ditto 1/8.

Well, 1/4 is probably not usable even with VR on, while at 1/2 the effects of VR is evident, though not usable.

Street Test

All with VR on.

1/15s Sharp.



1/10s. Acceptably sharp.



1/6s some hint of sharpness but look at the words on the MRT poster... no good.



1/4s no good.



1/8s ... sharp



1/4s acceptably sharp.



1/2s ... what was I thinking, miracle lens?


Conclusions
Looks like the VR is extending my handheld sharpness to 1/8s, below which the percentage of acceptable sharpness drops quickly.

This lens is giving me 1 stop VR only, since I can confidently hand-hold 1/15s.

Good enough? Well, depends on the purpose.
(a) Give D60 to my daughter for her projects etc - VR will help.
(b) For my personal use, VR is of not much advantage, just 1 stop.

I will still bring my f/1.4, f/1.8 and f/2.8 lenses whenever I envisage low light shooting.

Wednesday, March 24, 2010

My Work

Well, this is not really a blog but a place for me to place some links relating to my work as an EH&S professional.

China MOH GB page

Tuesday, March 23, 2010

Quick Test Nikon AF Nikkor 80-200mm f/2.8D (2 Touch)



Decided to do a quick "window" test of my recently acquired (used) Nikon AF Nikkor 80-200mm f/2.8D. My second so called "pro" zoom lens, the other being the Nikon AF Nikkor 20-35mm f/2.8D.

Test totally unscientific, hand held. Nikon D300 in Aperture Priority, ISO200, Picture Control D2x Mode 1, 12-bit raw, batched converted and resized to 1024 width using Photoshop Elements 6.0.

Oh the comments are based on overall impression, not pixel peeping; i.e. looking at the photos in quick succession rather than examining the micro details.

10 April 2010 - did some field test with this lens. See AF 80-200mm f/2.8D Revisited.

Performance Wide Open and 1 Stop Down
First the extremes: 80mm and 200mm, at f/2.8 to f/4

Click on photo for 1024 width photo.

80mm f2.8



80mm f/4


At 80mm, there did not appear to have much improvement in resolution/ sharpness/ contrast going from f/2.8 to f/4. More actual photo tests would be needed to confirm this.

200mm f/2.8


200mm f/4



200mm f/5.6


At 200mm, the improvement in resolution/ sharpness/ contrast going from f/2.8 to f/4 was significant! Less so with 105mm and 135mm but still visible (you'll have to take my word for it). It begs the question if I should avoid using 200mm f/2.8... Will need to test this out in actual photo situation.

Performance at f/5.6

Next I figure that most time (other than those low light situations) the lens would be most used at f/5.6. So a series of photos at f/5.6 were taken for the marked focal lengths.

80mm f/5.6



Hmmm, nice and sharp.

105mm f/5.6


135mm f/5.6


200mm f/5.6


Yes yes yes...

So the lens is really nice and sharp throughout its range at the most frequently used apertures of f/4-f/8 (take my word for it, or you do your own tests). At f/2.8, there is some softness noticeable at all focal lengths except 80mm, so more test are required to see if I can live with the softness wide open.

Conclusions
With this limited, unscientific, hand-held test, the lens came off with almost flying colours. I will need to see if 200mm at f/2.8 is so weak that I cannot use it... Hopefully not.

Epilogue
I had always wanted to see what the diffraction effect was but had never tested it. In field situations when shooting macro both UW and topside I had used f/16 and f/22 quite generously, and had not seen any visible drop in sharpness. Well, I had nothing to compare with.

So I did a short test and gone all the way to f/16 on several focal lengths.

200mm f/11


200mm f/16


My my, the difference is evident! There is indeed lost of sharpness at f/16.... Well not that I am likely to use f/16 on a tele-zoom...

Similar results are seen in the other focal lengths.