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 05/02/2006 12:38:59 PM · #1
I am frustrated with my moon photos. I just purchased a D70s and have a nikon 1000mm f/11 mirror lens. I used this lens to take pictures of the moon many times with my N65 with no problems. My exposures were usually around 1" or 1/3sec with iso400 film, and came out great, and in focus. I mounted my D70s to this lens last night and the view finder shows I am in focus for a perfect shot but everytime they come out blurry. I am useing the same tripod and a wireless shutter remote. I found the best exposures were about 1/8sec., iso 800. I acutally went to 1/30sec. which is better but then I am losing my light. Are digital exposures that much different?
 05/02/2006 12:46:19 PM · #2
The only thing I'm going to say is that digital does not suffer from the law of reciprocausity (hope i spelled that right). With that said, check your histogram in order to get a good exposure.
 05/02/2006 12:50:08 PM · #3
Are you sure it's a focus issue? A one second exposure is a long time... I read once that the moon will actually begin to blur at 1/4 second due to movement.

And besides... what f-stop were you shooting at to get it down to 1 second? I always thought the moon pretty closely followed the Sunny-16 rule (i.e. 1/60 of a second at f/16 for ISO 100 film).

I ask about the f-stop for two reasons: 1) the lens itself will degrade in performance beyond about f/16 or f/22, but not only that, 2) your camera's ability to resolve the image will degrade beyond f/11 or so. (see this article for a discussion of diffraction and its effects on digital camera sensors).

05/02/2006 12:55:37 PM · #4
This looks like a really good article for shooting the moon.
 05/02/2006 12:57:21 PM · #5
I was using an f-stop of 11. You would think that 1/30, f11, iso800 would reduce any blurr. I will play with it again tonight to see if get it better.
 05/02/2006 01:05:48 PM · #6
At ISO 800, don't forget that the Nikon will be generating a fair bit of noise, possibly increasing with the temperature (probably not an issue at night), so noise reduction algorithms will strip a LOT of detail out of the picture...

That is one of the main reasons a lot of people go Canon. Especially astro-photogs. Canon's noise profiles are generally lower and therefore the noise reduction can also be less.

Try it at ISO 200 at 1/8...

I don't think diffraction is an issue on the D70 at f/11. I believe it starts somewhere around f/16 for the D70. It will likely only start to show up noticeably around f/22 according to the articles I read...

Aside from that, I really can't think of anything major that should be an obstacle.

Let us know how things go!
05/02/2006 01:08:55 PM · #7
Originally posted by rexermoto:
I was using an f-stop of 11. You would think that 1/30, f11, iso800 would reduce any blurr. I will play with it again tonight to see if get it better.


But.... shouldn't that be way too much light for your ISO speed? I mean, that oughta be too much light for ISO 100 even, right? (see the article I linked to early - he does, in fact, mention the Sunny-16 rule)

And besides, the quality of your image will drop quite a bit shooting at ISO 800 instead of ISO 100. Why so high? Aren't you introducing a lot of noise (which might actually create the illusion of an unsharp focus)?

Also, at 1000mm, your tripod had better be really stable. :-)
05/02/2006 01:19:12 PM · #8
Originally posted by dwterry:
Also, at 1000mm, your tripod had better be really stable. :-)

You're missing the 1.5 magnification factor due to 35mm lens. Add another two "reallys" in there. lol
 05/02/2006 01:31:24 PM · #9
I agree , dropp the iso 800 down to 200 to clear up the noise and use a faster shutter. Like f10 and 1/13sec at 200 and move around a bit from there
 05/02/2006 01:34:06 PM · #10
Originally posted by nemesise1977:
I agree , dropp the iso 800 down to 200 to clear up the noise and use a faster shutter. Like f10 and 1/13sec at 200 and move around a bit from there


His 1000mm/f11 lens won't do f/10. :-)

I still think it's a lot of light (based on past readings and the recommendation of following the Sunny-16 rule). I guess I'm just gonna have to go out and "shoot the moon" myself now!
 05/02/2006 02:11:06 PM · #11
Originally posted by _eug:
Originally posted by dwterry:
Also, at 1000mm, your tripod had better be really stable. :-)

You're missing the 1.5 magnification factor due to 35mm lens. Add another two "reallys" in there. lol


And the D70s has no mirror lockup and it slaps the mirror pretty hard...

Did you (OP) us a remote shutter release with it?


05/02/2006 02:23:58 PM · #12
Originally posted by cryan:
the law of reciprocausity (hope i spelled that right)


I don't know what the hell that word is, but I love it! ;)
 05/02/2006 02:47:26 PM · #13
Originally posted by posthumous:
Originally posted by cryan:
the law of reciprocausity (hope i spelled that right)


I don't know what the hell that word is, but I love it! ;)


A few too many letters... it's

reciprocity, as in reciprocity failure.
 05/02/2006 03:05:02 PM · #14
A few notes:

1. It's "reciprocity" failure and it's a major issue with film, especially color film. "Reciprocity" means 1/2 second is twice the exposure of 1/4 second and half the exposure of one second. All films eventually run into reciprocity failure at some point on the long-exposure end of the scale. As an illustration, back when I was shooting architecture we used a lot of Kodak color negative film and the reciprocity failure became noticeable with exposures longer than 1/2 second on the daylight balanced film, but the tungsten balanced film was good for a full minute before failure set in. It got very extreme, too. If the "correct" exposure, as calculated, was 5 minutes at f/22, you'd have to shoot 30 minutes at f/22 to get a one stop "over" exposure, and you'd have to shoot two HOURS at f/22 for a "two stops over" negative.

Fortunately, the Polaroid 55 P/N 3x5 films we used for arranging lighting and props cloesly mimicked the reciprocity characteristics of the tungsten negatove film, so we had a built-in reality check there.

For practical purposes, "reciprocity failure" has the effect of lowering the "film speed" (ISO) more and more dramatically as exposure times increase. So far as I know it's not a factor in digital.

2. Mirror-reflex lenses, by design, do not have an adjustable f/stop; he's stuck with f/11.

3. The "sunny 16" rule tells us that at ISO 100, the correct exposure for a daylit schene is f/16 at 1/100. ISO 400 would be 1/400, and so forth. The face of the moon is, by definition, a "daylit scene" and this exposure would be in the ballpark to render the moon bright-but-not-blown. So at ISO 100, his correct exposure would be 1/200 at f/11. Of course, everything else in the picture would go black, but the moon would be "properly exposed", more or less.

R.

Message edited by author 2006-05-02 15:06:23.
 05/02/2006 03:13:57 PM · #15
Remember that the brightness of the moon and the daytime sky are very close to the same. During the day get an exposure reading of the sky with your camera and then use those same values as a starting point to photograph the moon.
 05/02/2006 03:27:41 PM · #16
Originally posted by Azrifel:
Originally posted by _eug:
Originally posted by dwterry:
Also, at 1000mm, your tripod had better be really stable. :-)

You're missing the 1.5 magnification factor due to 35mm lens. Add another two "reallys" in there. lol


And the D70s has no mirror lockup and it slaps the mirror pretty hard...

Did you (OP) us a remote shutter release with it?


The D70 DOES have a mirror lockup (1st item in the utility menu)
You can also use the time release function to control shutter release shake

05/02/2006 03:34:01 PM · #17
The d70 has mirror lock up, why wouldn't the d70s. My understanding is the only difference between the d70 and the d70s is a 2/10ths of an inch bigger lcd and updated AF firmware (which can be downloaded to the d70). Look under menu, open the set up menu, and scroll down until you see mirror lock up, it should be right above the video mode, and right under lcd brightness.
 05/02/2006 03:42:13 PM · #18
Incidentally, there's a phenomenon called 'blooming' that happens when a pixel reaches 'blowout'. It will be seen to 'spill' light to neighboring pixels. Sharp edges are no longer sharp edges.

If you were shooting 1/30 and you should have been shooting 1/200, that's about 3 stops overexposed. Of course, you have a little bit of room for error because you would be metering on the moon presumably, so this is probably sending you more like 1 full stop into 'bloom county'.

This will make the moon appear as a big ball of white crap. I noticed the same thing when I first shot the moon through a telescope.

Speaking of which, I really ought to post that here. Show what a Canon Powershot A80 can do when you stick a 1200mm reflector with a 12" disc in front of it... :)
 05/02/2006 03:42:23 PM · #19
Originally posted by nomad469:
...
The D70 DOES have a mirror lockup (1st item in the utility menu)
You can also use the time release function to control shutter release shake


I thought it was just for cleaning - it won't actually "expose" the sensor when the mirror is locked. At least mine won't. I usually use the hat trick for long exposures.

Message edited by author 2006-05-02 15:47:23.
 05/02/2006 04:45:26 PM · #20
Originally posted by nomad469:
Originally posted by Azrifel:
Originally posted by _eug:
Originally posted by dwterry:
Also, at 1000mm, your tripod had better be really stable. :-)

You're missing the 1.5 magnification factor due to 35mm lens. Add another two "reallys" in there. lol


And the D70s has no mirror lockup and it slaps the mirror pretty hard...

Did you (OP) us a remote shutter release with it?


The D70 DOES have a mirror lockup (1st item in the utility menu)
You can also use the time release function to control shutter release shake


The D70 has a maintenance mirror lockup, not a shooting mode mirror lockup. The same applies to the D70s. It is the only thing I do not like about the D70.
The timed release function is a good suggestion. I use an IR TV remote nowadays, so I didn't think about it.


05/02/2006 04:54:28 PM · #21
How about making a new moon in PS? ... suppose this defeats the object..
 05/03/2006 10:17:24 AM · #22
Thank you guys for all your input. I think I found my problem, it's the tripod. I was able to shoot the moon last night at 1/60, iso 320 with good results. I lowered the tripod to as short as it would go, which reduced the vibration factor. That worked better but I can't keep shooting everything from 2' off the ground. The D70s must have more shutter kick to it than the N65, plus my tripod isn't exactly top of the line. (Walmart Maybe) Looks like I am in need of an upgrade, any suggestions (reasonable price $100-$200) Thanks.
 05/03/2006 12:13:59 PM · #23
For cheap and heavy, check Amvona tripods. I think you can usually find them for 59-80 dollars.

If you are buying from a store, check Velbon. They make some great magnesium stuff which is often lighter and cheaper than the other big name brands. Velbon makes a very 'affordable' high end model with 4 sections in the legs that is very compact and fairly light when folded that gives the Gitzo and Manfrotto's a run for their money. It is tall enough to be used without extending the center shaft.

I use a Velbon QR system and find it to be VERY solid, even when mounting my 80-200 with 2x TC. (about 12 inches of heavy lensing)

Shop around for a head that you like, there are plenty of choices and they are often quite affordable.

I prefer (as do many others) ball-heads. If you will always mount in a fairly balanced or level position, get a ball-head rated for a bit more than your camera, but if you are going to be using more extreme mounting positions (perhaps rotated all the way up or mounted on a slider/extender), get something rated for at least double the weight of your camera in 'heavy' setup.

Incidentally, before you do this, go over your own tripod and make sure that all the adjustment screws that can be tightened are tightened. I sometimes forget to tighten the backup tightener on the center shaft and that allows extra play. Some guys never extend the center shaft.

I find that if I am careful, I can get somewhat decent performance from my cheap tripod even with my bigger camera if I leave the center shaft down.

Another thing you can do to stiffen the tripod up (specific to the legs) is to add weight. There might be a hook or something, but you can also just use a plastic bag if you like, looping the handles through and over the top shaft..
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