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Echoes1024

macrumors member
Original poster
Feb 10, 2006
32
0
I'm trying to take a picture of the moon, I'm using a 500mm fixed F8 lens with a 1.6x tele-converter on a D100 which has a lens factor of 1.5. So I think the focal length becomes: 1.5 * 500 * 1.5 = 1200mm (i hope this is the right way to calculate!).

Anyhow, as you can imagine its very hard to keep the camera steady on a tripod with such a long lens, I've tried using a timer with no luck. There are still slight vibrations. The lens is "Non-CPU" so I have to expose and focus manually. The focusing is easy, I just set the lens to "Infinity". As for exposure, I've found that I get the best results with a shutter speed of 1/30 with a fixed F8 aperture. But this is resulting in a slight blur of the image. I don't think that the image is out of focus because I shot one at 1/125 and that was quite sharp but yes, underexposed. So I'm confused here... should I increase the ISO? But I'm afraid that will add digital grain. I don't have a remote or cable release for the camera either.

What do you guys suggest?
 

iGary

Guest
May 26, 2004
19,580
7
Randy's House
Echoes1024 said:
I'm trying to take a picture of the moon, I'm using a 500mm fixed F8 lens with a 1.6x tele-converter on a D100 which has a lens factor of 1.5. So I think the focal length becomes: 1.5 * 500 * 1.5 = 1200mm (i hope this is the right way to calculate!).

Anyhow, as you can imagine its very hard to keep the camera steady on a tripod with such a long lens, I've tried using a timer with no luck. There are still slight vibrations. The lens is "Non-CPU" so I have to expose and focus manually. The focusing is easy, I just set the lens to "Infinity". As for exposure, I've found that I get the best results with a shutter speed of 1/30 with a fixed F8 aperture. But this is resulting in a slight blur of the image. I don't think that the image is out of focus because I shot one at 1/125 and that was quite sharp but yes, underexposed. So I'm confused here... should I increase the ISO? But I'm afraid that will add digital grain. I don't have a remote or cable release for the camera either.

What do you guys suggest?

Up the ISO, shorten your tripod to its shortest length, try to shoot at 1/500th and treat yourself to Noise Ninja. Remotes are cheap - get one.

That all should help.
 

Echoes1024

macrumors member
Original poster
Feb 10, 2006
32
0
iGary said:
Up the ISO, shorten your tripod to its shortest length, try to shoot at 1/500th and treat yourself to Noise Ninja. Remotes are cheap - get one.

That all should help.

Umm... do you really think it would be possible to shoot at 1/500? I shot at 1/125 and the pic was dark. Would the ISO help that much? :eek:

And as for the remote... I would get one except its not available where I live... :mad:
 

pdpfilms

macrumors 68020
Jun 29, 2004
2,382
1
Vermontana
arogge said:
Have you used mirror lockup or "anti-mirror shock"?
Mirror lockup in combination with a timer will eliminate all vibrations.

However:

Blur may be occurring at 1/30 due to movements of the moon itself. At 1200mm (equivalent), you're pretty close in there. And try just sitting and watching the moon through your camera for a few seconds... you'll see its movement at that magnification is quite visible. So I would also suggest upping the shutter speed to at least 1/60, along with the ISO.
 

Abstract

macrumors Penryn
Dec 27, 2002
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898
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What ISO are you using it at right now? You told us the shutter speeds, but if you're using your camera at ISO 200 or 400 or something, then yes, up the ISO to 800 and increase the shutter speed.

Lower the tripod to it's shortest point as well, like iGary suggested.

Blur may be occurring at 1/30 due to movements of the moon itself.

Wow, never thought of that.

And speaking of things you'd never think of, the light from the moon may not come straight into your camera. Ever wonder why stars look like they twinkle? Air flows, and air density at a particular location in the sky will constantly change. For example, the small patch of air to your left side may not be exaaaaactly the same as the patch of air to your right side even though they're so close together (a bad, exaggerated example). This is a bigger issue high up in the atmosphere, and since light is passing through different densities of air that's also constantly changing, light travelling from the moon through the Earth's atmosphere is constantly bending by a different amount due to these air density fluctuations. This is why stars look like they're twinkling, and hence why you may not get a steady shot of the sky at 1/30 second shutter speed.
 

Poeben

macrumors 6502
Jul 29, 2004
346
0
I would shoot at a minimum of 1/250 second. Remember the moon is a sunlit subject, so you should use a similar exposure to that of a daytime sunlit subject. At 1/30 you will definitely get blur from the movement of the moon/earth/camera etc especially with a long lens.
 

jared_kipe

macrumors 68030
Dec 8, 2003
2,967
1
Seattle
If things are sharp at faster shutter speeds, then obviously something is moving. Shorten the tripod, watch out for wind, enable mirror lockup and use the self timer.

I'm kinda surprised that you would call a reflex lens with a 1.5x (I don't know of any high end ones, all the high end teleconverters I know are 1.4x) sharp anyway. It isn't not sharp because of blooming or anything?

Maybe you can coordinate all of the mac rumors people to flash the moon at the same time, allowing you some more light.
 

Echoes1024

macrumors member
Original poster
Feb 10, 2006
32
0
Well the thought of the movement of the moon did occur to me but I didn't didn't it would be noticeable...

And what is a mirror lock up? (Sorry, I'm new to photography!). Does the D100 have it? I really should read the manual.

jared_kipe said:
I'm kinda surprised that you would call a reflex lens with a 1.5x (I don't know of any high end ones, all the high end teleconverters I know are 1.4x) sharp anyway. It isn't not sharp because of blooming or anything?

Well... the D100 and the lens aren't mine, they belong to my dad. I, personally, use a Coolpix 8800 but yeah now I wish I had bought the D50. The lens is quite old, I think he used it with his F3 or F4. And so I don't know really know about the lens' resolution but I've attached 2 pictures. One taken at 1/125th and the other at 1/30, maybe you can tell if the lens is good or not? I don't know much about tele-converters either, do they make a lens resolution worse?
 

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whocares

macrumors 65816
Oct 9, 2002
1,494
0
:noitаɔo˩
The 125th sec. one looks like it's not suffering from "mirror slap" to me. It looks more like the softness is due to the 500mm reflex lense + teleconverter combo.

Try boosting the ISO higher to get a higher shutter speed and a bit more exposure (maybe 250th and ISO x4). Also try removing the teleconverter; you may get better results.

I tried photographing the moon with a 500mm reflex. I wasn't pleased with the results. The 500mm went to eBay.
 

jared_kipe

macrumors 68030
Dec 8, 2003
2,967
1
Seattle
I'm not sure here, but maybe we're seeing blooming on the second image. By using brightness and contrast I can make the second image a lot brighter/usable. You should try the same thing, maybe try a shot at say 1/100 and see if you can't improve apon this. I would NOT raise the ISO. The images you showed are already a little noise, and I think it will only get worse if you start boosting it, as it is the D100 can't shoot less than ISO 200. I think with the various suggestions here (D100's mirror lockup can be found under Custom Function 24 and causes the mirror to lock up 1/2 second before shutter opens) you'll probably catch a few good images that can be made better in post.

Might as well take every combination you can think of, 1/125-1/30, and see which ones are usable, and then take off the TC and see if things are better. I wager they won't be, simply because even though resolution goes down when using TC's its generally still better than cropping.
 

iGary

Guest
May 26, 2004
19,580
7
Randy's House
It's savable, although the noise produced from bringing up the exposure isn't so desirable.

Do what Jared said and keep trying different combinations. :)

DSC_0001.jpg
 

jared_kipe

macrumors 68030
Dec 8, 2003
2,967
1
Seattle
iGary said:
It's savable, although the noise produced from bringing up the exposure isn't so desirable.

Do what Jared said and keep trying different combinations. :)
Our meathods must differ a little bit, mine didn't get that much shadow noise. Never the less, maybe running it through some noise ninja would work (I cannot I don't have it on this computer at the moment).
 

Abstract

macrumors Penryn
Dec 27, 2002
24,868
898
Location Location Location
jared_kipe said:
He's probably using ISO 200, its the lowest the D100 can do.

Why is he "probably" using 200? I wanna know how much more he can crank the ISO, and therefore use a faster shutter speed.

This entire thread is getting kind of cyclic if he doesn't reshoot and tell us how it went.
 

whocares

macrumors 65816
Oct 9, 2002
1,494
0
:noitаɔo˩
Abstract said:
Why is he "probably" using 200? I wanna know how much more he can crank the ISO, and therefore use a faster shutter speed.

Probably up to 1,600, but it gets very noisy (the range is 200-1600 I think on a D100).
I find noise to be acceptable on a D70s up to 800. And I've found a great (not cheap but not ludicrously expensive either) PS filter that does a great job at reducing noise. It's called Noise Ninja.
 

Echoes1024

macrumors member
Original poster
Feb 10, 2006
32
0
Well ok, I'm going to try different combinations tonight. Increase the ISO, use a faster shutter speed etc. I'll take shots with and without the tele-converter. The only reason I'm using this lens is because of the huge magnification, I do have a 70-200 but that won't go anywhere near this, obviously; though its resolution is quite good.
 

jared_kipe

macrumors 68030
Dec 8, 2003
2,967
1
Seattle
Abstract said:
Why is he "probably" using 200? I wanna know how much more he can crank the ISO, and therefore use a faster shutter speed.

This entire thread is getting kind of cyclic if he doesn't reshoot and tell us how it went.

I think a black background+white/grey moon is possibly the worst time ever to "crank" up the ISO. There is generally way more noise in dark and colorless subjects. And the D100 goes all the way up to 6400, but I don't think I'd use over 200, MAYBE 400 if it was necessary.
 

Abstract

macrumors Penryn
Dec 27, 2002
24,868
898
Location Location Location
The D100 goes up to 6400? No way! :eek:

I think it likely goes to ISO 1600 as well, but I think that at ISO 800, his image quality will still be ok. Howver, dark areas will be a problem like you pointed out, but if he takes 2 photos, one at ISO 800 or 1600, and one at ISO 200, and then "cut out" the moon from the ISO 200 image and layer it on top of the ISO 1600 image so that the moon from the ISO 1600 image is used, while the black areas from the ISO 200 image is used. I don't know how to do this myself, but people who use Photoshop can do this sort of thing quite easily once they learn how.
 

Echoes1024

macrumors member
Original poster
Feb 10, 2006
32
0
jared_kipe said:
I think a black background+white/grey moon is possibly the worst time ever to "crank" up the ISO. There is generally way more noise in dark and colorless subjects. And the D100 goes all the way up to 6400, but I don't think I'd use over 200, MAYBE 400 if it was necessary.

Yeah, I guess but I don't really have another option to try... First I'll shoot at ISO 200 and vary the shutter-speed between 1/30-1/125 and then then I'll try shooting with a higher ISO, i'll apply noise reduction to shots which are grainy. Maybe I'll get a good picture using one of the above methods...
 

jared_kipe

macrumors 68030
Dec 8, 2003
2,967
1
Seattle
Abstract said:
The D100 goes up to 6400? No way! :eek:

I think it likely goes to ISO 1600 as well, but I think that at ISO 800, his image quality will still be ok. Howver, dark areas will be a problem like you pointed out, but if he takes 2 photos, one at ISO 800 or 1600, and one at ISO 200, and then "cut out" the moon from the ISO 200 image and layer it on top of the ISO 1600 image so that the moon from the ISO 1600 image is used, while the black areas from the ISO 200 image is used. I don't know how to do this myself, but people who use Photoshop can do this sort of thing quite easily once they learn how.
I think it might look goofy though, and just to make sure.... do you not believe me about iso 6400?

http://www.dpreview.com/reviews/nikond100/page16.asp
 

Echoes1024

macrumors member
Original poster
Feb 10, 2006
32
0
What about the D100's built-in Noise Reduction? Would that give better results then Noise Ninja or other similar software?
 
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