PF Photography: Tips, Tricks, & Photo Sharing

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For smoke I would recommend using high powered flashes. You shouldn't really have to be going all the way up to 1/1250 to get a sharp image of smoke.

I would think even 1/320 would be sufficient, in which case you could lower your ISO to say 400 and increase that f stop to f8.
 
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Andre said:
That's a good fire Andy,

Edit: I'd wondered what I could do to reduce that noise in the last frame.

not bad! I posted images straight off the camera (jpg) since I was unusually busy today- no time to post process...

khemist said:
For smoke I would recommend using high powered flashes. You shouldn't really have to be going all the way up to 1/1250 to get a sharp image of smoke.

I would think even 1/320 would be sufficient, in which case you could lower your ISO to say 400 and increase that f stop to f8.

Yes, definitely- a (remote) flash would make my life easier. I don't have one, tho. As for the shutter speed, I still had blurring at 1/320-ish; but to be fair it's not clear if that was from not being in focus, me moving around, or some combination of the two.
 
Andy Resnick said:
not bad! I posted images straight off the camera (jpg) since I was unusually busy today- no time to post process...

Sure, I know how that feels. Anyway, generally I was irritated by the noise in general and not very happy with the standard noise reduction, losing detail and sharpness. So I did a web search to see if there were smarter solutions. I think "neat image" is doing a superior job, as you can see. So no more grainy pea soup.
 
http://img440.imageshack.us/img440/2550/dsc2504.png

http://img207.imageshack.us/img207/1443/dsc2503.png

http://img577.imageshack.us/img577/523/dsc25031.png

If you're up for a challenge, try to photograph smoke.

These were taken with my old film 50/1.8, object distance at close focus.Exposure at 1/100s (khemist was right) ISO 1600 using a white LED for illumination (no strobe).

The last one is a 1:1 crop from the middle one.
 
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Andy, the pictures look awesome! I love the first picture of the fire! I wish I could take up your challenge, but no fireplace :(

Andre, that's the sunrise? I thought it was the sunset at first because of the color. All my sunrise are clear and bluish :( Beautiful picture :!)
 
Andre said:
...
This is what you might see, if you're very lucky, when waiting for the sunrise and you happen to look the other way. But you have to realize that you have to drive back down into the valley to capture it in a more dramatic setting.

rswkco.jpg

sourlemon said:
...

Andre, that's the sunrise? I thought it was the sunset at first because of the color. All my sunrise are clear and bluish :( Beautiful picture :!)

To be more clear, you are looking at the full moon, making herself up to set below the horizon, as the sun is about to rise. Obviously the dawn is coloring the clouds.

As said, I went down a bit in a valley to have the moon closer to the little hill slope there.
 
These are the last smoke images for a while- too many upcoming deadlines. Here's a few single images and a series of a 'smoke drop'- all full-size images are available on my blog. My graduate advisor and I are going to try submitting one or a few to the AIP Gallery of Fluid Motion- stay tuned for that. The images were processed in Neat Image (thanks, Andre) at either 'remove all noise' or 'remove half of the noise' settings, and a final gamma and level corrected applied in ImageJ.

http://img341.imageshack.us/img341/7027/dsc26611filtered.png

http://img836.imageshack.us/img836/7531/dsc2505filtered1.png

http://img507.imageshack.us/img507/4349/dsc2654filtered1.png

http://img15.imageshack.us/img15/419/dsc2781filtered.png

http://img818.imageshack.us/img818/9215/montage2.png

Coincidentally, when I was out last evening, an airplane contrail evolved into this:

http://img43.imageshack.us/img43/4237/dsc28351.png

The pattern was fairly uniform and long- I only captured 10% of the trail- and was very stable.
 
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I was wondering when someone would ask :) My vice of choice is EtOH- preferably a mug o' Wild Turkey.

In the interest of science, I went through an entire box of White Owl cigars- nothing but the finest! That's another reason why I'm done with the smoke photos for a while- my lungs are not happy.

Such pretty photos, such an ugly back-story...
 
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Andre said:
..

rswkco.jpg

I decided to enter it in a contest but before that I did some tone mapping to brighten the shadows:

10AB205B5862457198489579650BA241.jpg
 
I've been trying to do a little astrophotography lately but I'm having focusing issues with one of my lenses. It doesn't seem to want to go to infinity causing all my pictures of the night sky to be blurry. Anyone know of a way to fix this? I've attached a sample image of the orion nebula taken at 300mm with the focus ring set all the way to the focus stop.

243euj9.jpg
 
Could be you are focusing BEHIND the infinity. Try to focus slightly closer.

And I am not joking, some lenses are built this way - infinity is not at the end of the focusing ring range, but a little bit earlier.
 
Might be just another cliche but this is the best I have caught
 

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Andre, good luck with the contest. It's a really good picture. (haha, and yes, you caught me. I was confused whether that was the sun or the moon.)

amal, that's beautiful. I really like how you captured the branches in with the mountain.
 
Borek said:
Could be you are focusing BEHIND the infinity. Try to focus slightly closer.

And I am not joking, some lenses are built this way - infinity is not at the end of the focusing ring range, but a little bit earlier.

Thanks Borek but I already took that into consideration. The posted pictures is the absolute clearest image I could get. Setting the focus any closer would make the image even more blurry. I did this all with manual focus though. I'll give the autofocus a try next time assuming these clouds ever go away.
 
Hi everyone check this out. They were on my door.
 

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Topher925 said:
I've been trying to do a little astrophotography lately but I'm having focusing issues with one of my lenses. It doesn't seem to want to go to infinity causing all my pictures of the night sky to be blurry. Anyone know of a way to fix this? I've attached a sample image of the orion nebula taken at 300mm with the focus ring set all the way to the focus stop.

The focus does look a little off. If this is indeed the 'best focus' you can do, I'd like to know 1) how are you focusing (i.e. looking through a viewfinder or at a LCD), 2) are you using a mirror lockup camera setting? 3) are you using a shutter release cable?

The problem may not be focusing but mechanical vibrations.
 
Andy, I was manually focusing as the auto-focus just wasn't working very well. I was focusing by looking through the view finder (mirror down obviously). I tried focusing using live view but the LCD's on cameras just don't have enough resolution. No shutter release cable, just a 12s delay. I highly doubt its mechanical vibrations. I've used the same mount and setup several times with other cameras at similar focal lengths and never had any issues.
 
Topher, did you consider to leave everything manual and make several exposures whilst mechanically turning the focus ring some increments every time?

Also in 30 seconds exposure time, that cosmos above you does rotate a little. Maybe also try ISO 6400 and a few seconds?
 
Andre said:
Topher, did you consider to leave everything manual and make several exposures whilst mechanically turning the focus ring some increments every time?

Also in 30 seconds exposure time, that cosmos above you does rotate a little. Maybe also try ISO 6400 and a few seconds?

Andre, yes, that's basically how I got the above picture. Just took several shots at slightly different focal points.

The camera is on an equatorial mount with a relatively decent polar alignment. There shouldn't be much of any star trails with a 30 second exposure.
 
Topher925 said:
Andy, I was manually focusing as the auto-focus just wasn't working very well. I was focusing by looking through the view finder (mirror down obviously). I tried focusing using live view but the LCD's on cameras just don't have enough resolution. No shutter release cable, just a 12s delay. I highly doubt its mechanical vibrations. I've used the same mount and setup several times with other cameras at similar focal lengths and never had any issues.


FWIW, when I use the camera timer (even the setting that raises the mirror before 'exposing' the CCD) instead of a cable release, my star images also look fuzzy.

In any case, I am unfamiliar with an equatorial mount- does it actively move to keep the stars in position? How does it move?

Oh- the blur spots appear circularly symmetric- is that correct? Does their appearance change over the field of view?
 
Indeed tripods may not be as stable as you want them to be. Anything around in the environment that could cause vibrations?

But Topher, you'd want to exclude that it's the lens giving the problem, so I would make a lot of test shots of the horizon in bright light, auto and manually focussed with wide open aperture.
 
Here's a stack of 80 0.4" exposures of the Orion nebula taken at 800mm f/5.6, ISO 1250

http://img526.imageshack.us/img526/6885/orion1crop.png

The image was severely cropped and shown here at 25% scale. I can resolve the four main stars in the Trapezium, but I'm still working on getting both the nebula and the resolved stars at the same time in the final image.

I'm sure I can get a better image than this with better seeing conditions.
 
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Andy, I think that it is somewhat noisy. Otherwise fantastic.
 
Try keeping ISO 800.,Decreasing shutter and increasing aperture by 1-2 stops.