PF Photography: Tips, Tricks, & Photo Sharing

[khemist]

Here is a recent shot from my trip to Arizona, north of Phoenix.

air by Hoxie Photography, on Flickr

The vignetting is due (most likely) to the lens adapter; I have a full-frame camera (Sony a850) and the lens is a Nikkor 400mm f/2.8 ED-IF. The Nikon-Sony adapter has a small lens to line up the image planes correctly, and (so I'm told) use of long focal length lenses can cause vignetting. I don't get vignetting with either the 15mm or my old 50mm Nikon lenses.

God damn that's like a 6000 dollar lens!

 

[Borek]

Compare the reflections of the trees in the water, which is obviously moving - it's not so clear if there was any wind moving the vegetation.

At this particular moment there was almost no wind, the branches were completely still. The single frame could be blurred by accident, but lack of sharpness here is not accidental. Actually I selected this particular place/crop as it nicely shows the general feeling.

EOS7D let's me select almost any shutter speed (as long as it is below that defined by frame rate) I want, and in fact I did more testing - it doesn't look as quality changes with shutter speed selected. At least not for the type of movies I shot - mostly still landscapes.

I plan to do some testing with the moving objects, but that will be next stage.

 

[AlephZero]

Some more thoughts on the movie experiments:

The image degradation may be coming from the playback/frame grabbing codec, not from the recording.

Also, the first frame of any video is by definition "special" because it has to contain the full image. Later frames that only contain the changes may converge to a higher quality image.

You can often see that "convergence" effect with video conferencing (using professional quality video links and equipment, not webcams!) where the picture quality reduces if there is a some rapid movement, and then recovers over the next few frames (of the order of 10 frames, I would guess).

 

[Andy Resnick]

Here is a recent shot from my trip to Arizona, north of Phoenix.

God damn that's like a 6000 dollar lens!

Worse- new it's a $10k+ lens. Mine's been gently used and was gotten for 20% of that. So I don't mind losing 5-10% of the frame... :)

 

[Borek]

Taken (and a little bit photoshopped) today. Some random girl taking pictures at Old City in Warsaw.

Well, her randomness is definitely skewed

Edit: that's not good, I am in love with a picture I took. Call me Pygmalion.

 

[fuzzyfelt]

Great photo!

 

[Borek]

Thanks

 

[Andy Resnick]

I don't know if the idiom "losing your marbles" is strictly American, but the meaning is similar to "becoming frustrated or angry".

My semester just ended, so perhaps it is fitting to show these. The overall context is "photographing glass objects", and it's not easy to get a decent image of the colorful bits inside the clear glass sphere.

[PLAIN]http://img651.imageshack.us/img651/2568/dsc6776s.jpg

[PLAIN]http://img717.imageshack.us/img717/8026/dsc6784u.jpg

[PLAIN]http://img860.imageshack.us/img860/530/dsc6770p.jpg

The trick is not only precise lighting, but also tiny apertures (the smaller the better). A clean sensor is good to- mine's gotten dirty...

 

[drizzle]

MARZENAAAA! :!) :!) ... Huh, don't get me wrong people, but that's MARZENAAAA! :!)

Thank you so much Borek, I love that shot

Edit: Ops, it's not Marzena. :shy:

 

[Andre]

Well this is how it looks now;

This time I "exposed to the right" and then processed the RAW back to normal. That should take care of some of the noise

And this is from today.

Striking that the orchid flowers open so slow and last for months.

 

[Andy Resnick]

Pixel-peeping my 15mm images, I discovered that the images are only sharp in the central 20% of the frame, and out around the periphery the images are horribly blurry. The adapter has a lens element in order to place the focal plane of the Nikon lens at the Sony camera sensor plane, so I wondered if the adapter needed some optimization- the lens is not cemented in place and the lens position can be adjusted slightly.

Here's my test setup- all these images were taken at full aperture (f/3.5):

[PLAIN]http://img231.imageshack.us/img231/4569/dsc70671.jpg

and here is the extreme upper left corner of the image, taken with the adapter lens element seated all the way in, then moved about 0.5 mm toward the 15mm lens, and then a final position 1mm toward the 15mm lens:

[PLAIN]http://img9.imageshack.us/img9/4910/61801809.jpg

[PLAIN]http://img694.imageshack.us/img694/5508/midk.jpg

[PLAIN]http://img535.imageshack.us/img535/8254/outx.jpg

There's a dramatic improvement at 1mm. Moral of the story- don't be afraid to tweak your equipment.

 

[Andy Resnick]

As I mentioned above, tweaking the position of the lens adapter made a huge difference in performance of the 15mm lens: this should not be too surprising, as 1mm represents an 8% shift in focal length. Not only was sharpness improved, but chromatic aberration *vanished*.

So, I was pleasantly surprised to notice the same dramatic improvement with my 400mm- I was not expecting much, since I was only shifting the adapter lens 0.25% of the focal length (or 0.12% when operating at 800mm).

Here's images I took previously with the lens wide-open (f/2.8)

[PLAIN]http://img90.imageshack.us/img90/2923/dsc6872.jpg

[PLAIN]http://img59.imageshack.us/img59/8051/dsc68721.jpg

I wouldn't say the performance is bad- I figured it's a 40 year old lens, modern technology has surely improved things, so I just stopped it down to f/8 and the CA went away. However...

Here's an image I took last night, now with the adapter lens optimized (again, f/2.8):

[PLAIN]http://img6.imageshack.us/img6/3579/dsc7380o.jpg

[PLAIN]http://img692.imageshack.us/img692/8084/dsc73801.jpg

What a difference!

 

[Borek]

Wow, that's surprising.

 

[Andy Resnick]

I know! Thinking more, I should have realized that since lens aberrations scale as the f/# (or worse), the correction would be *more* pronounced for the 400mm than the 15mm. Now, if I can just get someone to loan me a Noctilux...

 

[Andre]

...

And this is from today.

Striking that the orchid flowers open so slow and last for months.

It's past high noon now. The last two buds opened the other day, while the first flower (lower left) withered. The total flowers were 12 at the lower and 10 at the upper branch.

Shot is back lit by the sun.

 

[Borek]

Thunderstorm over Warsaw and Marki (I can still hear it). I have heard it early enough to prepare to shot a video from the attic, these are just selected frames:

 

[Andy Resnick]

Thunderstorm over Warsaw and Marki (I can still hear it). I have heard it early enough to prepare to shot a video from the attic, these are just selected frames:

Awesome! I was getting ready to ask about photographing lightning- how did you do it (e.g. exposure times, method, etc)?

 

[Borek]

I suppose you more or less already guessed, but just to to clarify: video, with each frame shot at 1/30 sec. At 25 frames per sec "lost" time is about 17% of total, so it is hard to miss anything. But that also means pictures are shot at 1920x1080, and - as I signaled in some other tread - their quality is much lower than expected. This is 1:1 crop of one of the images exported from the video (using Avidemux):

and 1:1 crop of the same view, the same lens, but picture, not video:

Difference is huge. Night pictures (with long exposure times) are much better.

I just realized I have neutral filter ND8 somewhere, so I could try long exposure times. Unfortunately, at the moment thunderstorm is away and it is quite nice.

 

[Andy Resnick]

How much video did you need to shoot in order to get those few 'good' frames? I guess I'm asking about the efficiency... I can imagine shooting minutes of video and then having to extract out 3 or 7 frames.

 

[Borek]

Much less. For sure it depends on the thunderstorm. I got 11 OK pictures out of six minutes, plus there 2 or 3 that were technically unacceptable (artifacts - like only half of lightning visible in one frame, and other half in the next frame). Thunderstorms in Poland are not that active when it comes to lightnings. I have a feeling lightnings were much more frequent about 15 minutes later; unfortunately at that time thunderstorm was already on the other side of the house and we don't have a window on this side of the attic that would allow tripod use.

 

[Andre]

Must have been years since I saw my last good thunderstorm

Anyway, this decent fellow, upon observing my activities, enquired if he could be of any service.

So I mentioned that I would not discourage him from giving an aerial display by any means. So he wasn't:

I should not have zoomed in that much though, as he did not fit in the frame.

 

[Triple_D]

The http://www.lightningtrigger.com/index.html#home . I've never used one, but a lot of people say they work great.

 

[Borek]

Arrgh.

Few months ago I bought two Kingston Elite Pro Compact Flash 8GB 133x memory cards for my camera. They work perfectly. I decided before going for vacations I am going to buy another two. I bought two Kingston Elite Pro Compact Flash 16GB 133x cards (same line, same specification, just twice the size) from exactly the same, trusted source (one of the largest hardware distributors in Poland). And they don't work as expected - they are too slow.

It turns out those bought earlier work much better than the specification, they work at at least 266x. That's why I have not realized 133x is too slow. Now I have two useless 16GB cards and around $75 in the hole. One I will probably sell, as it is unopened, but the other...

 

[Andy Resnick]

random change of subject:

Last night I re-watched Gaspar Noe's film "Irreversible"

http://www.imdb.com/title/tt0290673/

and was again astonished at the opening cinematography. I'm not I could 'recommend' watching the movie (if you haven't seen it, it's rather disturbing in places), but if you choose to watch it, the opening 5-10 minutes are really impressive. I was completely disoriented; I had no idea if I was looking up, down, upside down, rightside up, sideways, backwards... I would have *loved* to see whoever physically moved the camera around do their 'dance'. Noe did the cinematography as well as direct- it's a fine piece of work.

The opening credits are disorienting as well- some letters (E, R, K, N) are reversed, and the credits sort of go off-kilter before completely overloading your brain.

Again, I think this crowd would appreciate the technique- the way an image can take something obvious and ordinary and make it confusing and unrecognizable.

 

[Andre]

Arrgh.

Few months ago I bought two Kingston Elite Pro Compact Flash 8GB 133x memory cards for my camera. They work perfectly. I decided before going for vacations I am going to buy another two. I bought two Kingston Elite Pro Compact Flash 16GB 133x cards (same line, same specification, just twice the size) from exactly the same, trusted source (one of the largest hardware distributors in Poland). And they don't work as expected - they are too slow.

It turns out those bought earlier work much better than the specification, they work at at least 266x. That's why I have not realized 133x is too slow. Now I have two useless 16GB cards and around $75 in the hole. One I will probably sell, as it is unopened, but the other...

Apparantly the optimum choice seems to be the Transcend 400x CompactFlash Card, 32GB goes for some 65 euro. I'm just ordering one.

 

[Borek]

Apparantly the optimum choice seems to be the Transcend 400x CompactFlash Card, 32GB goes for some 65 euro. I'm just ordering one.

Please let us know how it works. Seems cheap.

 

[Andre]

Please let us know how it works. Seems cheap.

Sure, happy to.

Until now I managed with a single 8gb Extreme Sandisk 60MB/s (400x), nice and fast. Sure enough using standard RAW and the occasional movie, it fills up fast, but I always travel with my laptop and an additional external harddisk, so I emptied the card very frequently to process the pix and back them up on the external harddisk.

However, should the card fail somehow -and I lost several SD's in the past-, I'm stuck, so it's more for redundancy than for lack of storage to have a second card and then this 32Gb seems to be the most bang for the buck.

 

[Borek]

I have two 8GB cards (as explained earlier - Kingston Elite Pro, nominally 133x but in reality faster). With a laptop and external HDD that's perfectly enough for pictures, but not enough for HD movies, and I plan to shot some. Unfortunately I won't be able to buy anything more before leaving Warsaw for vacations. I sold one of the 16GB cards, I plan to use other for pictures - while it is too slow for movies, as long as I don't shot more than a picture per 2 sec that shouldn't be a problem (especially taking into account buffer built into camera). For fast situations (sport/bird pictures) it won't work.

 

[Borek]

Sorry, no strawberries.

(For newcomers: larkspur was a user at PF, active up to about two years ago. Her pictures were always great, one of them was a picture of strawberries in the rain - in a way similar to what I took today. Unfortunately, her pictures are no longer hosted at old urls.)

 

[fuzzyfelt]

No apologies necessary (IMO), it is wonderful without strawberries!

 

[Andre]

Please let us know how it works. Seems cheap.

The card just arrived, it's in the camera. Burst in RAW+JPG roughly on par with the sandisk card, that is, after the first 6-8 shots the rate goes down to maybe 4 frames per second. Movie mode seems fine too.

 

[Andre]

Update

I downloaded the evaluation version of flash memory toolkit and did a read test with both cards (write test blocked). Both claim to be 400x with reading (up to) 60MB/s for scandisk and 90MB/s for the Transcend.

On my computer though, it was 16.7MB/s average for the old Sandisk and 18.8MB/s for the new Transcend. Not what you expect but it compares better

Edit:

Of course you can test write speed too just by writing. So I formatted both cards and then wrote a 1.05 GB big folder containing 45 pix to each.

A modern duracell 8MB USB memory stick required 3:19 minutes for that or 5.3 MB/s, the scandisk was ready in 1:38 minutes (10.7 MB/s) and surprisingly the Transcend 1:06 minutes (15.9 MB/s)

Verdict: it's a keeper, the scandisk is now permanent reserve.

 

[Borek]

Thanks for the update. I see them here as well, unfortunately, I won't be able to buy one before leaving (it won't arrive in time).

So far your tests confirmed speed, let's hope it will be also reliable. I am always afraid of things substantially cheaper than equivalents.

 

[Andre]

Thanks for the update. I see them here as well, unfortunately, I won't be able to buy one before leaving (it won't arrive in time).

So far your tests confirmed speed, let's hope it will be also reliable. I am always afraid of things substantially cheaper than equivalents.

Yes I know the feeling, but it is just a feeling. Maybe, if you aren't a famous brand, you'd have to compete both with quality and low budget prices. I've seen a lot about that in the jeans branch.

So I am not pessimistic but I'll download the pix frequently.

 

[Andre]

Thanks Turbo

Here is a small selection. I just happened to shoot them this evening, unaware of this thread. The dog loved to play model and I got her all over me after the dash, every time, when I was laying there on the ground.

We won!

http://www.dpreview.com/challenges/Entry.aspx?ID=477595