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Jodokast96
Stupid people piss me off.
Premium Member
join:2005-11-23
NJ

2 recommendations

Jodokast96

Premium Member

Some Pentax Multi-Exposure Shots

Nothing special about the shots themselves, just wanted to show a few examples of the amount of noise (or lack thereof) from using this. The first is a combination of 9 30sec. (4min. 30sec. total) exposures and the second a single 30sec. exposure. All settings were the same, as were the RAW conversion settings, which were set to maximize the amount of noise.


PENTAX K10D
18mm 30s F3.5 ISO100




PENTAX K10D
18mm 30s F3.5 ISO100



I didn't get up early enough and it started getting light before I could shoot a 3rd series of 9 for a total of 27sec., but I'll see what it looks like tonight.

rogue_
I Have A Secret Window
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join:2001-10-17
Lake Hiawatha, NJ

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rogue_

Premium Member

I see some vertical banding in the second photo. This 'error' in the image does happen from time to time. It seems when the settinsg and light are just right (or wrong in this case) you will get that error in the image. Not a big deal as every time it's happened to me (maybe twice) I took another shot right away and with a slight change in shutter, aperture, etc the next image was fine. The fact that it was a multi-exposure shot might have actually contributed to the banding in this particular shot as you didn't pick it up on the first image and took a whole bunch more just like it.. lol

That first image is what it's all about though.. Sweet!

Jodokast96
Stupid people piss me off.
Premium Member
join:2005-11-23
NJ

Jodokast96

Premium Member

Yeah, I just noticed the banding when I was uploading them. Playing around with them a little more, it's in all of the shots I took, even the first one, but they were all at the same exact settings. I'll take a few more test shots later to make sure it isn't something else.

SandShark5
Long may you run
Premium Member
join:2000-05-23
Santa Fe, TX

4 edits

2 recommendations

SandShark5 to Jodokast96

Premium Member

to Jodokast96
[flamesuit on]

I'm not here to rag on your camera or your images, but I see nothing in those two shots that I would be especially happy with. The "banding" or whatever you want to call it is horrible. Would you print an image with those flaws? Like Gemologist See Profile says, "Just telling it like it is and it's my personal opinion."

Maybe I'm missing something, but why not just take a 4 minute and 30 second exposure instead of multiple exposures? I thought the multiple exposures feature was sort of an in-camera HDR, no? Oh, and before I get the virtual hell beat out of me , I'm not sure I could take a shot like that and have it be any better. I'm just trying to enlighten myself.

[flamesuit off]

rogue_
I Have A Secret Window
Premium Member
join:2001-10-17
Lake Hiawatha, NJ

1 recommendation

rogue_

Premium Member

Many cameras will produce banding. It's not so much a flaw with one camera as it is with all digital cameras. It's actually shot specific.

Jodokast96
Stupid people piss me off.
Premium Member
join:2005-11-23
NJ

1 recommendation

Jodokast96 to SandShark5

Premium Member

to SandShark5
Banding first. It's something I just noticed now for the first time. I've been checking into it, and it seems to be something that had to do with the original firmware, which I have. Updating that now to see if it improves. No, it's not something I'm happy about if the firmware doesn't fix it.

As to why not take a single long exposure? That was the purpose of testing this. The noise in the single 30sec. exposure is far greater than that in the 4.5min. multi-one. That's all I was trying to show here, how doing it this way reduces noise. And no need for the flamesuit, lol. These pics are far from perfect, but they weren't meant to be either, lol.
Jodokast96

2 recommendations

Jodokast96

Premium Member

Quick test shot with the new firmware seems to have eliminated the banding.

Gemologist
Premium Member
join:2001-11-15
USA

Gemologist to Jodokast96

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to Jodokast96
Banding is no biggie, Canon 20D has far more severe banding then this and Canon NEVER even bothered to fix it!

I understand exactly what Joda is trying to show and the shots proves his point! The lack of noise that can be gotten using the multi-exposure feature! Just like the dark shot I posted in the other thread, not a shot worth keeping, just a shot to prove how little (almost NONE!) noise there was in it and that you could bring the details out of the shadows forever!

SND2005
Premium Member
join:2001-09-15
Im Over Here

SND2005 to Jodokast96

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to Jodokast96
I don't see how this is a useful under the conditions in which you shot. A factor of how much noise is in the shot is the amount of time the shutter is open. Any camera is going to exhibit at least some level of noise at 30 seconds. The fact that you used a low ISO is counter intuitive IMO. You created more noise @100 with 9 shots than you would have with one. For example, no NR @ ISO250 f22 via ACR- »i.dslr.net/pics_cache/13 ··· 3426.jpg

Why not shoot a higher ISO with a sorter shutter speed & combine fewer shots? The level of noise @ ISO100 in the image is similar to ISO 1600 for the same camera based on your shot.

Don't get me wrong, this feature really seems to have its place, but it seems to me this might be pushing it just a bit, no?

No_Strings

join:2001-11-22
The OC

No_Strings

Maybe I misunderstand the feature. I thought that the averaging of multiple images actually reduced the amount random elements - noise - canceling it out, and leaving the repeating elements of the picture intact (rushing water effects notwithstanding).

Gemologist
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join:2001-11-15
USA

Gemologist to Jodokast96

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to Jodokast96
Uh.. I think that, if you read Joda's posts, you will realize that this is just an EXAMPLE showing the low noise, nothing more. I gather from reading that he didn't want to print and hang/sell this shot.. just experimenting, lol.

Not sure who took the other shot of the bridge, nor what it is supposed to show!? But that shot looks about as useless, too soft and lacking all contrast not to mention very noisy in the shadows with all those blotches and no shadow details at all. If you lighten up the shot joda posted there is a ton of shadow details and very little noise that comes out, in the shot of the bridge if you lighten at all it is tons of noise, blotches (artifacts), and no details.

It is not so much about the "exact" shot Joda posted, just the general technique and how useful it is.

Just like this shot, done with same technique, is useless, but it shows how useful the technique can be! Pop this into PS and bring up the exposure or whatever... even just using the shadows & highlights tool in PS maxing out the sliders adds little noise (what noise there looks like film grain) and there is insane amounts of details in the shadows. This is just out of camera JPEG, the RAW file has even more possibilities!

PENTAX K10D
70mm 1/15th F0 ISO100



It is all about the possibilities!
05241201 (banned)
Where is Rob A?
join:2006-03-23
Eagle River, AK

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05241201 (banned) to SandShark5

Member

to SandShark5
LOL! Banding?!?! The K10D is nearly perfect in this situation, it blows the pants off the Canon models its class.

SND2005
Premium Member
join:2001-09-15
Im Over Here

SND2005 to Gemologist

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to Gemologist
said by Gemologist:

Uh.. I think that, if you read Joda's posts, you will realize that this is just an EXAMPLE showing the low noise, nothing more. I gather from reading that he didn't want to print and hang/sell this shot.. just experimenting, lol.

Not sure who took the other shot of the bridge, nor what it is supposed to show!? But that shot looks about as useless, too soft and lacking all contrast not to mention very noisy in the shadows with all those blotches and no shadow details at all. If you lighten up the shot joda posted there is a ton of shadow details and very little noise that comes out, in the shot of the bridge if you lighten at all it is tons of noise, blotches (artifacts), and no details.

It is not so much about the "exact" shot Joda posted, just the general technique and how useful it is.

Just like this shot, done with same technique, is useless, but it shows how useful the technique can be! Pop this into PS and bring up the exposure or whatever... even just using the shadows & highlights tool in PS maxing out the sliders adds little noise (what noise there looks like film grain) and there is insane amounts of details in the shadows. This is just out of camera JPEG, the RAW file has even more possibilities!
[att=1]

It is all about the possibilities!
I know he doesn't want to hang the shot. That wasn't my point.

The point is that his shot doesn't show LOW noise. It in fact shows much more noise than would be present in a single shot at the same settings!

The example...yes- its has noise and problems, but it has FAR less noise right out of camera at only 1 single exposure and NO post work. Perhaps ISO2-400 with half the shutter time would better illustrate the point of the low noise in the scene that was shot.

Nobody is questioning the features ability, I'm saying it has its limits. Just telling it like it is and it's my personal opinion.

SandShark5
Long may you run
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join:2000-05-23
Santa Fe, TX

1 recommendation

SandShark5 to 05241201

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to 05241201
said by 05241201:

LOL! Banding?!?! The K10D is nearly perfect in this situation, it blows the pants off the Canon models its class.
Now, that's the kind of enlightenment I was talking about! I knew I should have stayed out of this thread.

rogue_
I Have A Secret Window
Premium Member
join:2001-10-17
Lake Hiawatha, NJ

rogue_ to Jodokast96

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to Jodokast96
This thread is awesome.

Jodokast96
Stupid people piss me off.
Premium Member
join:2005-11-23
NJ

1 recommendation

Jodokast96 to SND2005

Premium Member

to SND2005
Are we even looking at the same pictures? The single shot at 30 sec. has far more noise than the shot at 4.5 min. If a single shot at 30 sec. has that much noise, can you imagine what a 270 sec. single exposure would look like? And who cares what ISO it was shot at? I could have done them both at 1600 and the only difference would have been that they both would have shown more noise, but the single exposure would have still shown more than the multi one. And I already stated that I didn't have the time to run a multi-exposure at 30 sec. to compare equal times by each method. We've got cloudy skies tonight, so it will be at least one more night until I can get that one.

The overall point wasn't to show excessively low noise, but to show that the multi exposure gives you lower noise than a single exposure. And no, the level of noise at 1600 is actually more than what is shown in the first example. Besides that, even this shot didn't quite come out as I'd liked, higher ISO and shorter shutter doesn't give you the star trails. There are a couple of things I can try to get them right, and if I do, I can guarantee a better shot this way than a single exposure.

SND2005
Premium Member
join:2001-09-15
Im Over Here

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1 recommendation

SND2005

Premium Member

said by Jodokast96:

Are we even looking at the same pictures?
As it turns out, NO! I'll start a new trend here in the forum, I'm sorry!! I totally mixed up the shots. The shot does appear to be higher ISO, maybe 800 or so. It's very well controlled however. I'm still of the opinion that you could get even less noise by bumping up ISO a tad and reducing increasing shutter speed.

What really has me even more puzzled is how your single 30 second shot could have that much noise. Maybe its a flook or by-product of the feature, I hope it's not representative of long exposure performance for the Pentax line.
-dan

Jodokast96
Stupid people piss me off.
Premium Member
join:2005-11-23
NJ

1 recommendation

Jodokast96

Premium Member

LOL, I was hoping that was what you did. No, it's not representative. You probably just missed it earlier, but I bumped up the RAW conversion settings to achieve maximum noise with the shots, and then used the same settings for each. If you look at the jpgs straight out of the camera, the exposure is much darker, such that the trees are just shadows and I dont even think the chimney is visible. At those settings, yes the noise is much, much less in both shots. The reason the second shot looks like a higher ISO is because I was creeping up on sunrise, so there was a bit lighter. BTW, that isn't light from the sun in the lower right, but rather light from a cell tower, billboard, and shopping center a few hundred yards beyond the trees. The sun was actually rising on the left of the shot and way out of the frame and not for another hour or so.

Anyway, I was just trying to show how much noise difference there was with each method. If I can dig it up, I think I have an older shot at ISO 1600 for 30sec. wide open. If I remember correctly, that is a noisy, ugly shot, and I'd suspect that the banding is probably really bad too, lol. I'm really glad I got that taken care of.