What lens size for Lunar Photography?

FowlersFreeTime

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I was curious for those of you with the knack for Astrophotography: What size lens do you need to get a decent moon shot that fills most of the frame?

I saw this lens and it got me curious:

Of course, on one hand I see that price and think "not bad, add to cart", but on the other hand perhaps I should just save for the Sony 70-350mm which has many more uses than just taking pictures of the moon...

Regardless I think the original question could yield useful answers for other forum users who may search it later on.
 
Hi Chris a 400-500mm lens will achieve a good moon shot with clarity of the surface of the moon mountains/craters/deserts etc but you would need a moderate to low aperture number.

For the milky way and to go further into deep space a small wide angle prime will suffice say 20/24 mm again with the lowest possible aperture number
you have (F1.8 - f2.8). As you probably know, to get good shots of the milky way you really need to ID a "Dark Spot" (an area with no city/night time ambient lighting in your area) during the last 3 days of the old moon and rise of the new moon at the time that the moon is waining, more usually 12.00am to 3-4.00 am.

If you are interested in astronomy there is a very good APP called Photopills for forecasting the position of the milky way anywhere in the world or any other astronomical feature for that matter as well as giving you GPS coordinates etc etc....

Hope this helps.
 
In addition, having a camera with a sensor that provides a high resolution will help with Post Processing cropping as well.
 
Hi Chris a 400-500mm lens will achieve a good moon shot with clarity of the surface of the moon mountains/craters/deserts etc but you would need a moderate to low aperture number.

For the milky way and to go further into deep space a small wide angle prime will suffice say 20/24 mm again with the lowest possible aperture number
you have (F1.8 - f2.8). As you probably know, to get good shots of the milky way you really need to ID a "Dark Spot" (an area with no city/night time ambient lighting in your area) during the last 3 days of the old moon and rise of the new moon at the time that the moon is waining, more usually 12.00am to 3-4.00 am.

If you are interested in astronomy there is a very good APP called Photopills for forecasting the position of the milky way anywhere in the world or any other astronomical feature for that matter as well as giving you GPS coordinates etc etc....

Hope this helps.
All very good points, thank you.
 
In addition, having a camera with a sensor that provides a high resolution will help with Post Processing cropping as well.
now, you're just trying to sell me an A7RV aren't you ;-)
 
Chris, reflex lenses are rarely as sharp as a standard configuration. They suffer from poor contrast as well. There are a few examples that are worth their salt. Nikon made one that was pretty good. Minolta's 500/8 AF was exemplary and can be had for about $75 less than that. I think I paid $185 shipped for mine with case/caps/hood/filters in like-new condition.

By and large though you're better off to stay away from them. You'd be further ahead with an old 350-400 MM something or other and an adapter and use MF, which is pretty easy since it's the moon. Most inexpensive lenses like that are likely to be at f/5.6 or above.
wow, I guess you get what you pay for! Thanks for the warning.
 
Personally, I would never (again) buy a reflex lens. As @Brownie says, they are rarely sharp enough. When I shot film I bought a Sigma 500 f8 reflex in Canon EOS mount. I took exactly one roll of film with it and sold it as soon as I saw the results.
 
I'm a little surprised that the replies have been recommending a fast lens (f1.8-2.8) for lunar photography. In my experience the moon is much brighter than you think and I've found it's better to use an F stop around the 'sweet spot' of the lens rather than opt for the widest setting. It's more important to be stabilized on a high enough shutter speed and pay attention to correct focus and exposure. I've had quite good results from several lenses 400, 500 and 600.
Moon reflected r.jpg
  • ILCE-7RM3
  • FE 100-400mm F4.5-5.6 GM OSS + 1.4X Teleconverter
  • 560.0 mm
  • ƒ/10
  • 1/640 sec
  • ISO 100
 
As in my post a fast lens is recommended for shooting the Milky Way and other deep space astrological bodies wherein light intensity is much lower and hence the need to shoot within a dead spot with no lunar light interference also - medium to low apertures were indicated for shooting the much more highly illuminated moon, and even in high ambient city/street light conditions , and which will cover the sweet spot on most long lenses……
 
Going back to the original question, what size lens to have the moon fill the frame, ideally you would need at least an 800mm to make it fill most of the frame. That is not practical for most of us, so the answer is the longest you can get. For Sony, the 200-600 lens racked out to 600mm would be ideal. However that's a $2K investment, so you would have to shoot wildlife or sports or other subjects besides the moon to get enough use to justify the cost. I would say 400mm with additional cropping would be the minimum you could get away with.

Of course this all depends on how the images are used and viewed. I mean if they are only posted on Instagram or Facebook and viewed on a cell phone screen, you could probably use a standard 50mm lens and crop it and get a shot that looks good on a phone. But I presume you want a bit more quality since you are on a photography forum.
 
I've used the 18-135mm kit lens on my a6400 and the results were... just OK. Even taking into consideration that 135mm x 1.5 APSC crop = roughly 200mm full-frame equivalent, the resulting image was small and didn't have a level of detail that wowed me.

DSC03293-sq.jpg
  • ILCE-6400
  • E 18-135mm F3.5-5.6 OSS
  • 135.0 mm
  • ƒ/11
  • 1/80 sec
  • ISO 100

This ^ is what sparked the original question.
It seems I would be best off with the Sony E 70-350mm which I have been eyeing for quite some time now. Who knows, maybe I will join the ranks of the bird photographers on this forum if I had such a lens at my disposal, but you better believe I would aim it up at the sky first change I get!
 
Best to shoot a burst when you can, the atmosphere will ruin half your long tele shots on most nights. I'd think a slow burst would be as good as any speed to catch the moment between ripples of turbulence.
 
Lots of good info here!

First: As mentioned, the atmosphere does indeed distort lots of your night sky pics, especially when close to the city, adding light pollution to the mix.

Also take into consideration your focal length and aperture. You want to use the lens with the settings where it best performs. As you may see in these charts from ephotozine, there's very different results depending on focal distance and aperture.

18 millimeters:

sony_18-135mm_MTF50_graph_at_18mm_1519740180.jpg


135 millimeters:
sony_18-135mm_MTF50_graph_at_135mm_1519740190.jpg


These charts are specific to your 18-135, not all lenses have their sweet spots in the same place as your 18-135 does. And I'm just choosing both ends of your focal length, if you visit the page you'll be able to fully browse your lens' capabilities. It does seem like narrow apertures are much better, which shouldn't be an issue considering that, as mentioned, the moon is super bright, so you don't really want to go full aperture.

If you can afford the time to investigate both your current lens and whichever you choose to get in the future, it will really pay off once you know how they perform in terms of contrast, definition and aberrations, at different settings. If you even perform a few tests, you'll notice right away how big a difference it makes! Same shot, different settings. Do try it out.
 

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@Ivanturas that is super helpful, thank you!
This 18-135 is still the longest lens I have, so I might as well try it tonight for the Eclipse. I do kinda wish I had rush delivered the other lens in time, but oh well, there will be other eclipses...
 
@Ivanturas that is super helpful, thank you!
This 18-135 is still the longest lens I have, so I might as well try it tonight for the Eclipse. I do kinda wish I had rush delivered the other lens in time, but oh well, there will be other eclipses...
Are there any rentals where you live? They may be out of long lenses for the eclipse, but who knows!
 
Are there any rentals where you live? They may be out of long lenses for the eclipse, but who knows!
Too short notice. But if I don't buy a lens in time for the next eclipse, I may rent from borrowlenses.com
 
In my experience as long as you have a clear night(no clouds(most important) and secondly no atmospheric disturbance related to air temperature and astral dust movements ) which of course you have no control over, you should be able to get a good shot of the moon and the eclipse. A 135mm at its sweet spot which will obviously limit the size of the moon in your shot. In general I have not experienced local light contamination playing such a big role in lunar shots as it does in milky way shots, the intensity of the light illumination on the moon which is vastly greater.

in respect of milky way shots, and i understand this is not your primary interest at this time, the reason wide angle lenses with low f values are used is more about minimising the exposure time of your sensor to the much lower light intensity of the Milky way. The wide angle provides for getting more of the milky way in your shot but equally and given the stars of the Milky Way and the earth have relative movement between them, a fixed camera as opposed to an alternate expensive astronomy set up which tracks the celestial movement, will result in coma, or small star trails(elongated stars) the longer your exposure time. Accordingly f1.8 or thereabouts, along with the much more light it permits to hit your sensor in a shorter time will go a long way to avoiding Coma in Milky Way shots........

A bit off track but may be of value in the future if your interest in astrological photography develops.
 
Too short notice. But if I don't buy a lens in time for the next eclipse, I may rent from borrowlenses.com
I'm glad we had this thread though! If i ever get the chance, I'd love to get a telephoto and that 70-350 seems like a good choice
 
Too short notice. But if I don't buy a lens in time for the next eclipse, I may rent from borrowlenses.com
I have never tried them, I am sure they are good. I (and some others I know) always use LensRentals.com, who are fantastic.
 
I have never tried them, I am sure they are good. I (and some others I know) always use LensRentals.com, who are fantastic.
I get the coupon emails all the time for BorrowLenses, for example "use code 'NOVEMBER15' for 15% off all rentals this week". Yes that is an actual coupon code, no I am not sponsored by them LOL.
 
Thank you for the reference shot Tim. To see how much of the uncropped frame it takes up: that really helps put things in perspective.
I could not stay awake for the eclipse due to a long night with fussy baby, but I did see the moon was full and bright when I looked out the window.
 
Wish I'd seen this question BEFORE last night's eclipse. Sorry. If you want to fill the frame you are going to need quite a bit of focal length - over 600mm.

Here's an uncropped image from my a6000 at the prime focus of a 658mm fl, f/7 telescope. You don't need a fast lens, although during a total lunar eclipse there isn't as much light as you think. I was shooting at about .8 seconds at iso 400. One thing where a faster long lens is better is as your focal length increases your untracked exposure limit does down. Along with the object, you are magnifying the effects of the Earth's rotation. My scope was tracking.

One thing you can do for tinkering with astrophotography is to download a free copy of an astronomy program such as Stellarium. You can enter your lenses focal lengths, and camera sensor size, and it will show the field of view of the set-up. That's what I did to plan for the eclipse. I wanted to see of I could use my larger 6" refractor with a 1200mm focal length instead of my smaller, shorter scope. I also use the program for taking deep sky images. According to Stellarium, my 6" scope wouldn't fit the whole moon on the sensor at 1200mm fl. If I had to guess I'd say the moon might just fit at about 1000mm fl.

Note, I rotated the camera between these two exposures, and I must have shifted my focus a tiny bit, so totality is a little soft.

Before totality it can be very challenging getting detail in the dim part while not blowing out the part still illuminated. You could bracket and combine images for an HDR image with better dynamic range. I haven't tried that yet.
2022Nov8LunarEclipseAlmostTotality.jpg
  • ILCE-6000
  • 4/5 sec
  • ISO 400
2022Nov8LunarEclipseTotality.jpg
  • ILCE-6000
  • 1.3 sec
  • ISO 400

stellarium-moon.jpg

Hope this helps.

Tom
 
This is good info! I have an 850/5.6 telescope (6" mirror) that should do nicely, some day soon. I'd need to set up my tracking platform, adjust the collimation to do its best, and rebalance everything for my A7.ii - assuming it can attain prime focus, which may be another issue. Given all that, it won't happen tonight, I'm exhausted just from typing this .. o_O 'twas a long day!
 
We had clouds this morning. I checked the sky before heading off to the polls, but no luck.

One thing of note in my shot is how flat the moon looks. You'll always get more depth and detail in a side-lit shot, but then the trade-off is the moon isn't full. This was also a 600mm shot, but cropped and side-lit in an evening sky, hence the blue.

DSC00212 by telecast, on Flickr
Now, that's a good-looking lunar photo! I'm also more inclined towards side-lit images, they have so much more volume to them! Also, stacking exposures may provide you with more visible area of the moon's surface, while still keeping its volume... although I do understand why some people may consider it too much post processing.
 
I have used 1120mm a few times (on a FF body) for moon shots and the sensor coverage is quite good, without being so large in the frame that earths rotation becomes frustrating (otherwise you need to continually adjust the tripod head between shots). In my case it's an adapted Canon 400mm F/5.6 lens with stacked 1.4x and 2x teleconverters. So I believe that another good choice would be the Sony 200-600 with a 2x TC.

And as already stated by somebody else, these are not typically worth buying just for moon photos due to their price.
 
Alternative choice: a used Tamron 150-600 in Minolta A mount + LA-EA5 adapter ( or LA-EA3 as this is an SSM lens). AF speed is slow but fast enough for moon shots and static birds and airshows ( it handles side to side aerobatics just fine ). This is a pretty sharp lens, up to 500mm. 600mm is usable for moon shots: use sequator to stack shots ( or not if you don't feel like it ) and you'll end up with shots that fill half the frame in cropped ( APS-C) mode. Sharpness depends on a lot of factor ( air temp, wind, humidity, pollution, etc) but on a good night, results will be great :)
 
Astrophotography is a whole other rabbit hole to go down, although how deep you go depends on how hard core you want to get, what equipment you already own and the depth of your pockets. If you need a long lens for another aspect of photography, it'll open up a few more possibilities when shooting the sky. All I needed was a 2" prime focus adapter to use my a6000 with my scopes. I have considered something like the 200-600 zoom and a TC because that would be handy for birds too.

As mentioned above, sharpness will become even more critical when you are doing astrophotography because even a tiny error is easily noticeable with stars in the image. Focus is my biggest problem because it can look sharp in the viewfinder, but can end up revealing focus errors when viewed on a screen. Stars require perfect focus.

Seeing is another problem when you start using any kind of magnification and when your exposures start to get longer, and then there's blurring from the Earth's rotation. At first I thought my image of totality might have been blurred by thin passing clouds but there are two stars in the image that are tiny round disks which told me my focus had drifted. Still looked great in the viewfinder. If I hadn't been chasing sucker holes in the clouds, I would have used my Bahtinov mask to focus on a star first, then move to the moon, but I felt pressured for time so I winged it. Sometimes when I'm not sure of focus, and I have the time, I'll bracket my focus a little.

It's very common for people to think that the best time to look at, and photograph the moon is when it's full. Unless you want to get a shot showing the rays around the larger craters, its not a good time, because as Ivan said, the moon looks flat. Having some shadows reveal details and give a sense of depth.

Jim, what brand is your 6" reflector? I'm curious because f5.6 is unusual.
 
I'm a complete novel at this, but NYE while I had my cam on tripod, just after the 9pm fireworks, I photographed the moon at 240mm on A7iv using sony 24-240 G series zoom.

The images below have only been cropped, not edited so they can be improved with post processing..

I read a rule called the lunar 11. 100 ISO with F11... or, is it 100 ISO with shutter speed 100?

On this shot I couldn't remember the rule, as I cannot now, so I shot shutter speed at 1/100 with ISO 100, using auto aperture. It was too dark because my apertures only go down to F6.3 at 240 focal length. A better lens would manage I figure.

I then used manual zoom (with the built-in magnification feature of the A7iv), so I could visually check the focus and exposure and thus changed the ISO from 100 to 125.

GJF03817.jpeg

Not cropped...


GJF03818.jpeg

Cropped.

I want a 200-600 right now@!


Gaz
 
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Nice job!

Yes, the Moon likes a long focal length.

Here's a shot from last month through my 1200mm fl, f8 Telescope of the Mars occultation. at this focal length Mars is starting to show a disk. I don't have any images of Mars close to the lunar limb with the Sony, because I switched to a dedicated astro-imager for real close-ups.

I'm a bit of a wing-it photographer. Since I have lots of room on my memory cards I will bracket the heck out of my exposures and pick the bests shots and trash the rest.

Exposure varies a lot with the Moon depending on the phase. In this case the 6" scope pulled in a lot of light so this is 1/600sec.

Tom

2022Nov7MarsOccultationSony09.jpg
  • ILCE-6000
  • 1/1600 sec
  • ISO 320
 
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