Long lenses for Moon exposures

<p>I was wondering what would be some good inexpensive long or tele lenses for 4x5 for taking photos of the moon?</p>

<p>My rail goes to 445mm, so that is the long limit.</p>

<p>Why bother? It takes 1000mm lens to fill up a 35mm frame as it is.</p>

That's fine.

 

So a 300 LF lens should fill up a 35mm frame, right? And be pretty large on a 6x6 frame.

 

300 appears to be a standard, relatively available LF length. I don't know the lengths that are longer to search for,

besides searching 310, 320, 330, etc. If that's what one needs to do, fine, I just want to know if that't what I need to do,

that's all.

<p>Yeah, what Mike said.</p>

<p>The moon subtends an arc of about 0.5 degrees.</p>

<p>To render the image 2" high on film would require a lens of about 229 inches (roughly 5,820mm).</p>

<p>- Leigh</p>

 

<p>Richard,</p>

<p>I think you don't understand the relationship between focal length and image size.</p>

<p>A lens of a particular focal length will render an image of the moon at one particular size, always.<br>

It doesn't know or care what film or sensor is sitting behind it.</p>

<p>A 300mm lens will give exactly the same size image whether the film is 35mm or 6x6 or 8"x10".</p>

<p>- Leigh</p>

 

<blockquote>

<p>A 300mm lens will give exactly the same size image whether the film is 35mm or 6x6 or 8"x10".</p>

</blockquote>

<p>Really?</p>

<p>When I shoot 80mm on 6x6, the image(field of view) fills the frame approximately as an 80mm on my 35mm frame(discounting the rectangular format).</p>

<p>If I superimpose the 6x6 negative frame over the 35mm negative frame, the stuff is larger in the 6x6 frame. It is not tiny like the 35mm. It is larger, but you are saying it is the same size.</p>

<p>If I shoot the moon with the 6x6 with an 80mm lens. And I shoot the moon with 4x5 with a 90mm lens. The moon on both negatives, when compared to each other negative to negative, will be almost the same size, correct?</p>

<p>Remember also that as the lens focal length gets longer, the shorter a shutter speed you'll need, else the motion of the moon will blur the image. This is why astrophotography is done with tracking mounts that pan to follow the motion of the object being photographed.</p>

 

<p>With my recent experiments, Moony 11 rule works just fine.</p>

<p>That is to say, that at F11, at 200 ISO, 1/200 produced good results. Just too small for what I want to use them for. No motion blur. At 200mm.</p>

<p>It does move(it doesn't really move I know) at a pretty good clip, the positioning between shots even taken in succession were notably apart.</p>

<blockquote>

<p>If I shoot the moon with the 6x6 with an 80mm lens. And I shoot the moon with 4x5 with a 90mm lens. The moon on both negatives, when compared to each other negative to negative, will be almost the same size, correct?</p>

</blockquote>

<p>Yes. That's what I said before.</p>

<p>If you shoot the same focal llength on both film sizes the images on the negatives will be exactly the same size.</p>

<p>- Leigh</p>

 

<p>That is just experimentally and intuitively wrong to me.</p>

<p>Why shoot large format in the first place, if the negative image is not bigger, Leigh?</p>

<p>4"x5" is larger than 35x24mm or 6x6cm to me, but not to you. You are saying that if I sandwich the two different size negatives together in the negative carrier, that the stuff on the negatives will fall right into each other given the same focal length lens.</p>

<p>A person filling the frame of a 35mm frame, at about 35mm tall, will still be 35mm tall on a sheet of film 4x5 inches. And not 5 inches tall?</p>

<p>Let me rephrase the point.</p>

<p>I have a 80mm MF lens on a MF camera. I have an 80mm LF lens on a 4x5 camera. I shoot the moon with the 4x5 camera with the 80mm LF lens and with the 80mm on the MF camera. I develop each. And I take some scissors and cut the sheet of 4x5 film down to 6x6, to crop the moon(cut the black part off each side).</p>

<p>You are saying that the moon in each is going to be the same size in both pieces of (6x6) film, correct?</p>

<blockquote>

<p>You are saying that the moon in each is going to be the same size in both pieces of film, correct?</p>

</blockquote>

<p>That's correct. How would the lens know what film is behind it?</p>

<p>Shoot an image on 8x10 film, then take a pair of scissors and cut out a 24x36mm rectangle. Does the image size change?</p>

<p>I shoot 35mm, 6x6, 4x5, and 8x10, so I'm speaking from experience, not theory.</p>

<p>- Leigh</p>

 

<p>Ok, if you say so.</p>

<p>The stuff on your 8x10 negatives must be really tiny then. I dunno, I don't have an 8x10.</p>

<p>What kind of lens do you use to get a person to fill the frame with that? What kind of distances do you shoot people with it?</p>

<p>Richard ...<br>

I think you are confusing <strong>field of view with magnification</strong>.<br>

A lens of "X" focal length, regardless of the format of the film, would produce a certain size moon disc. If we say that disc is the size of a quarter coin, then it would fill a 35m film frame, but only be a small part of a 4x5 frame.<br>

If (as Mike says) it takes a 1000mm lens to fill the ht. of a 'landscape' oriented 35mm frame, i.e. 24mm ...<br>

then if you use a 1000mm lens on the 4x5, the moon will be the same size, the quarter coin.<br>

If you want to fill the ht. of a 'landscape' oriented 4x5 frame, i.e 4 inches or approx 100mm, then you would need a lens around 4000mm focal length.<br>

That's how I understand this.<br>

Jim</p>

<blockquote>

<p>The stuff on your 8x10 negatives must be really tiny then.</p>

</blockquote>

<p>Huh??? I can make the image whatever size I want.</p>

<p>I suggest you get a book on photographic optics. It appears you're unfamiliar with some very basic concepts.</p>

<p>- Leigh</p>

<p>This is why the normal lenses for the formats are 50 mm for 135, 80 for 6x6, 150 mm for 4x5 and 300 mm for 8x10. When you use a 50 mm lens on 4x5 (e.g, 55 mm Apo-Grandagon), you have an extreme wide-angle. Something that fills the frame of a 135 mm camera with a 50 mm lens will be just part of the scene with the 50 mm lens on 4x5. You could take the 4x5 lens and cut it with scissors to 24 x 36 mm and have the same result as the 50 mm lens on the 35 mm camera. Adding the film of the 4x5 camera expands the field of view ... if the lens can cover. You need a longer lens on a larger format to have the same field of view, in proportion to the format size.<br>

To make a large image of the moon, e.g., filling a 4x5 film, takes a telescope rather than a camera lens.<br>

Since your camera has an extension of about 445 mm, the longest non-telephoto lens that you can can use is a 450 mm. Probably some of them can be used with 445 mm extension since they will have a Flange Focal Distance slightly less than their focal length. For example, the 450 mm f12.5 Fuji-C has an FFD of 425 mm. To go longer you will need a genuine telephoto lens, which focuses with an extension well under its focal length. For example, the 600 mm Fuji-T has an FFD of 384 mm -- it will give you an image of the moon twice as large as a 300 mm lens. Maybe not inexpensive... Then look for old Schneider telephotos. Also look at the size of the shutter.</p>

<p>Ok,</p>

<p>I confess, I am thoroughly confused now.</p>

<p>Alright, strike all that retarded stuff I wrote previously.</p>

<p>Are there inexpensive telescope/lens adapters for large format cameras?</p>

<p>Richard,<br>

How about a crop sensor DSLR with a 500-800mm lens? Or it has to be on film?</p>

<p>Richard, relatively, yes there are, but there is no inexpensive way to get a large, greater than 2" in diameter, direct projected original image of the moon on a piece of 4x5 film. Unless your budget is probably greater than $50k.</p>

 

<p>Here's the rule: The diameter of a moon image in millimetres is given by the lens focal in millimetres divided by 100. What you capture that image on can't possibly make any difference. The lens does not know what you put behind it.</p>

<p>All 50mm lenses yield moon images 0.5mm in diameter. All 10,000 mm lenses give a moon image 100mm in diameter; and so on.</p>

<p>Shutter speed selection is influenced by the fact that the moon moves across the sky by its own diameter in two minutes. Even a 1 minute exposure results in a fat sausage shaped moon. A 1 second exposure delivers a moon that is out-of-round by 1 part in 120; and so on.</p>

<p>Perhaps this will help:<br /> <img src="http://www.mayadate.org/pix/Opticsc.jpg" alt="" /><br /> Given an image of height H and a lens of focal length F...<br /> If you want to increase the image height to 2H, you must increase the lens focal length to 2F.<br /> The same is true of any other factor, be it 3x or 26x or whatever.</p>

<p>Please note that the size of the sensor/film does not appear anywhere in this equation.</p>

<p>- Leigh</p>

Re exposure times: if we're talking about taking a picture of the moon itself, i.e. the moon being the thing that needs to be exposed properly, even shutter speeds in the region of 1 second are way too long.<br>The moon is lit by 'full power' sunlight. Just as, during the day (of course ;-) ) anything here on earth is. That sunlight is filtered by our atmosphere before it reaches the lens, and that will have an effect (just as we need slower speeds for terrestrial scenes when it's cloudy).<br>But basically, the sunny 11/16 rule works, i.e. using an f/5.6 lens (and there's no reason to stop down) and ISO 100 film on a clear night, the shutterspeed needed will be around 1/500.<br>So the good news is that the moon being on the move is not a problem.<br>The bad news, of course, is that there is no lens that will project a frame filling image of the moon on 4x5" film.<br><br>However...<br>You can 'build' a complex system, using one longish, but not impossible, lens to project an aerial image of the moon, another, short lens to take a (macro) picture of that aerial image.<br>That way you can get the moon to fill the frame. But you will be enlarging the image as produced by the first lens, with all it's limitations (so use a very good lens). The resulting quality however will be better than what you get by just enlarging a small image of the moon captured on film.<br>It's a bit of work though.

<p>If you are open to DIY projects you might try to adapt a spotting scope. Some 30 years ago I put together a shop-made jug to hold a Bauch&Lomb Discoveror scope in front of a press camera. The size of the image is adjusted by moving the 'scope further from the film plane. focusing is done by focusing the dcope. This is called "Eyepiece Projection".</p>

<p>I got a few dramatic shots of the moon rising behind a farm whindmill. The motion of the moon can be a problem.</p>

<p>The biggest problem is managing the bulk of the whole arrangement. If you really want that long telephoto look in LF at low cost, this can be <em>made</em> to work. </p>

<p>Please let us know what you do and how it works out.</p>

<p>Sorry I am not reading all the threads so I hope not being redundant.<br />Shooting the moon and expecting to fill your frame on 4x5 is literally impossible, not to mention, the largest lens you can find will be extremely expensive. I believe the largest would be an 800mm, hard to find. Likely, your only option there will be to purchase a reproduction lens (for press printing), use it in the barrel (no shutter, perhaps no diaphragm) and still will be very expensive and hard to find. Or to find an old aerial spy lens. They were used in the II WW. The aspect ratio in different formats has been clearly explained here.<br />A well, you will be facing another can of worms. Aperture vs time. Only on a motorized telescope tripod can "overcome" this pitfall and that, if the motion is perfectly set. You better option would be: if you would have a converter to adapt your camera to an observatory telescope. LOL<br />Perhaps the only and best option as mentioned here is to shot it in 35mm, a 600 to 800mm fast lens (f4.5 or f8) and the slowest film speed you can use. At that range, likely you will be able to afford a max of 15 seconds before blur. Good luck in your very ambitious project!</p>