Super telephoto lens.

[Anbesol]

For playing around with astro-photography, I'm wondering what kind of super telephoto would do what I want. Of course, ideally I'd be going with the 600 f4 Minolta, but, I dont have $8 grand to spare. There is quite a range of options though, everything from cheap off-brand Phoenix lens going for under $100, to Sigma's and Sony's reflex mirror lens, and all the way up to the 600mm f4.

Question is, how important is the optical performance, if always focusing at infinite focus distance, and shooting at ~f16 is fine? If using the phoenix, would the moon be surrounded by a huge purple fringe?

I am thinking of getting a cheap piece of crap just for the specific use of shooting the moon and astrology. But may hold out for a mirror, can't see myself justifying $8 grand on a lens for quite a while...

[Canuck935]

Actually, for anything besides the moon or general night sky I would look into a telescope that you can mount your camera to. Because of the motion of the earth, you would have to use either a stacking method (stacking together many short exposures) or get a telescope that automatically tracks.

I haven't actually done any astro-photography, so don't take my word on any of this. However, I'm pretty sure that most of what I've seen was done with camera mounted to scope and stacking images.

This looks like a good resource. http://www.astropix.com/

[Anbesol]

Ah yes, you would tempt me with those pricey telescopes ;). Stacking multiple exposures? Is the tonal range like insanely wide in space photography?

I don't expect much from those cheap crap ultra-telephotos, just some cool compositions of star constellations, the milky way, the moon, and so forth.

[OldClicker]

Ah yes, you would tempt me with those pricey telescopes ;). Stacking multiple exposures? Is the tonal range like insanely wide in space photography?

I don't expect much from those cheap crap ultra-telephotos, just some cool compositions of star constellations, the milky way, the moon, and so forth.

I think the stacking is in place of very long exposures required to get enough light and avoid the noise. Take multiple short shots and 'stack' them together. You also need something that will track the sky to eliminate the star streaking. - TF

[rongarrett]

For playing around with astro-photography, I'm wondering what kind of super telephoto would do what I want. Of course, ideally I'd be going with the 600 f4 Minolta, but, I dont have $8 grand to spare. There is quite a range of options though, everything from cheap off-brand Phoenix lens going for under $100, to Sigma's and Sony's reflex mirror lens, and all the way up to the 600mm f4.

Question is, how important is the optical performance, if always focusing at infinite focus distance, and shooting at ~f16 is fine? If using the phoenix, would the moon be surrounded by a huge purple fringe?

I am thinking of getting a cheap piece of crap just for the specific use of shooting the moon and astrology. But may hold out for a mirror, can't see myself justifying $8 grand on a lens for quite a while...

I've dipped my fingers into Astrophotography just a teeny bit. I have a telescope, {Bushnell}. Be advised that you will face many many hurdles if you really pursue astrophotography. First you need to live in Colorado to get the clear skies you will need. Also absolute darkness, anywhere in a city will have too much light pollution. Figuring out how to use a powered telescope is a feat in itself. There is a good reason not may people are good at it. You will invest many many bucks to be well enough equipped to get really awsome images.

Having said the above, I have an image I took of the moon with my Canon 400mm F/2.8 lens with 1.4 tele adapter and D40. It was taken when the moon was close to the horizon which caused it to appear a vibrant yellow color, caused by the earth's dirty atmosphere. Individual craters can be easily seen in a 17 X 22 image. It is an attention getter. I have sold several of the images.

Maybe some day I will tackle astrophotography in a serious way. For now I'll just stick to moon images if I can find another night without the haze from a power plant that is about five miles away from spoiling things. Let us know how you make out. There are tons of sites devoted to astrophotography available with a little browsing.

[Dougjgreen]

Here's a dirty little secret: Digital Cameras that have electronic shutters are nowhere NEAR the best equipment for astrophotography. Because they tend to have no mirror lockup capability, and the battery wears out during long time exposures. The best gear is a 30+ year old fully mechanical film SLR (doesn't even need a working light meter - since you'll never use it). The only features that it needs is to be light tight, have a working shutter with Bulb setting, and a Mirror Lockup capability. You can easily pick up a camera like this for under $50 on ebay - especially if the meter's busted, you can get one for around $20 that otherwise works fine. You can possibly also pick up a camera that is ideal for this at a flea market or garage sale for $20 or less. You also need a threaded cable release, that costs around $5. You'll also need to buy some 35mm film. I recommend Black and White, from either Ilford, Kodak, or Fuji.

Good examples of the cameras that are ideal for this are: Nikkormat FTn, Minolta SRT-101 (make sure it's an early version with Mirror Lock Up), Pentax Spotmatic, Canon FTb, or Olympus OM-1. Personally, I'd go with the Nikkormat, because I'm partial to the Nikon lens mount, but any of the others are fine too. If you're really living large, you can buy an old Nikon F or F2, or Canon F-1, and get a Waist level finder with for it which is ideal for viewing when the camera is pointed toward the sky. Those cameras with WL finders would end up being around $200, but bargains are available with careful shopping. I happen to have a Nikon F2 with a Waist Level finder (and broken electronics so the meter won't ever work) that I got really cheaply due to the electronics issue - that I would use if I were ever doing astrophotography. Those bodies cost $100-150 in full working order, plus $30-50 for the waist level finder. My F2 body cost me just $40 because the battery chamber electronics are broken.

The next thing to pick up is, if you already have a good telescope with a clock drive, get a telescope to camera adapter with a t-mount for the camera that you end up buying. This item would cost under $100.

If you don't have, and don't plan to get a good telescope, get a good used 500mm or 600mm Mirror lens. These can also be bought used for around $100 to $200 on ebay. I personally have a 500mm Tokina f8 lens that's typical, that I bought for around $60 on ebay. Tamron and Sigma, and a the Russian MTO also made good mirror lenses that you can buy cheaply used. These are all better than a current Phoenix, and they cost around the same. However, if you don't use a telescope with an equatorial mount and a clock drive, you will be limited to short exposures, because the earth's rotation will appear to move the sky, and you'll get star streaks. You can buy equatorial mounts separately from places like Edmunds Scientific.

BTW, the astrophotography is even better in most of Utah or Nevada (but not near Vegas or Reno) or Montana or Wyoming than it is in Colorado. It's even great in the remote Eastern parts of California, like Death Valley.

You will also need to have a good, sturdy tripod.

[Dougjgreen]

I haven't actually done any astro-photography, so don't take my word on any of this. However, I'm pretty sure that most of what I've seen was done with camera mounted to scope and stacking images.

I'm actually sure that most of what you've seen was done with an equatorial mount with a clock drive, and lengthy exposures, not stacking of short exposures.

[Canuck935]

Nice to see some experienced folks chiming in here. :thumbsup:

[OldClicker]

I'm actually sure that most of what you've seen was done with an equatorial mount with a clock drive, and lengthy exposures, not stacking of short exposures.

Even stacked would need the drive, wouldn't it? Stacking just helps get rid of the long-sensor-time noise. The total time is still the same. - TF

[Dougjgreen]

Even stacked would need the drive, wouldn't it? Stacking just helps get rid of the long-sensor-time noise. The total time is still the same. - TF

Film doesn't have sensor noise. Serious astrophotography uses film, because of both the sensor noise issue, and the much greater desirability of manual mechanical cameras for time exposures, compared to electronic ones. When digital images are needed, they use film scanners.

[Anbesol]

Well, I am sure I will be getting the Zeiss 24-70, the 70-200G, the 300 f2.8 and the 600mm f4 before I start funding a venture of this cost caliber. I was merely thinking about those cheap crappy $100 never-heard-of-the-brand type 'vivitar'-esque lens, wondering if their performance would be so awful at the extreme telephoto and infinite focus distance, stopped down to f8 or so.

Curious about this exposure time - I go to Utah on a somewhat regular basis, when I'm in the mountains, away from all the cities lights and such, the sky is filled with bright constalations, the tonal varieties of the cosmos are vibrant and bright as well. Why the need for such incredibly long exposures? Is it the depths and variation of the tonal range? I have done virtually no astrophotography so maybe my eyes are just getting lost in the depths of space, and my metering photographers eyes conked out for the time. But I can imagine shutter speeds in the 5-20 second range covering a lot of what can be done with astrophotography, is that not correct?

Or are you talking about the sensor noise from the 5-20 second range? It sounds like you are saying that bulb exposures are required?

And why on earth would you reccomend black and white film? And miss getting the magnificent color tones of space??

[Dougjgreen]

Think exposure times in minutes, not seconds. If you are hoping to shoot constellations, you are looking at typical exposures on the order of 4 minutes at a minimum up to perhaps even an hour or longer. There is no way to use a light meter on light this dim. You are looking at trial and error, and LOOOOOONG exposures.

That's why you need a clock drive on an equatorial mount. If it was something that involved a 5-30 second exposure, you could get away with a stationary tripod. And that's also why a cheap, mechanical film camera is the way to go. And I can't reitterate enough, get an older used Mirror lens from a better brand, like a Tamron, Sigma, or Tokina, they can be picked up for under $100 on ebay, and they are much better than the current Phoenix/Vivitar ones.

BTW, don't confuse the current stuff with the OLDER Vivitar Series 1 Mirror lenses. Those were excellent, but they have become collectibles so they are not cheap nowadays - expect to pay much more for one of those.