Some beginning astrophotography questions

[Bklynse]

Hello,

I am new to this forum and would like to get some information regarding astrophotography.

I have a Nikon D3200 with 2 lenses (55-200mm and 18-55m).  The lenses came bundled with the camera, so I'm guessing they are very beginner-level (which has been OK so far)

Here are my questions (with apologies if they do not make sense):

1) Are these lenses sufficient for astrophotography or do I need to get a better lens?

2) If I need to get a better lens, what should I get: a zoom lens or a fixed lens?

3) If I am going to take pictures of the Milky Way or of planets and stars, do I need an equatorial mount?  If not, how can I counteract the east-west motion of the earth during long exposures?

Regards

 

[barbulo]

Hi and welcome to SGL, deep well of knowledge. Here´re my answers based on my short experience: 

1) Any lens is good for astrophotography (AP) as long as you accept its limitations/aberrations.

2) Normally fixed FL lenses are better constructed.

3) Maybe not for short FL lenses. However, there are "inexpensive" star trackers (Star Adventurer, Skyguider...) that will let you use longer exposure times (light pollution permiting).

Bottom line: astronomy in general and AP in particular are highly budget dependant. Be aware that once the bug bites, you´re lost.

[happy-kat]

^ Ditto 

If you are into DIY you could make a barn door tracker for your 18-55 lens. 

[Swillis]

Hello and welcome. 

The lenses you have will be ok to start with and enable you to get a feel for the hobby and determine how much you want to invest in the future. 

I started with a canon 75-300mm zoom lens which is pretty rubbish for AP, but it got me started and allowed me to invest in a star tracker first. I have now invested in a samyang 135mm which is excellent. It is probably the most recommended lens. Alternatives would be to look on eBay for fixed focal length lenses, but it sounds like this can be a bit pot luck. 

Before the star tracker I built myself a barn door tracker which was fun to build, but took a bit a setting up each night, and reduced my already limited imaging time. If your into DIY its worth a go, there are plenty of guides out there. 

Simon 

[Elp]

Try with what you have first. The best (or one of the best) lenses bar none for AP is the Samyang 135mm f2. If you want to do milky way then the Samyang 14mm, both these lenses have an ED coated lens so are good at controlling chromatic abberation, most lenses are poor for this hence why taking star images with most lenses presents a challenge, it also depends on your expectations, I also use vintage lenses. Having something that counteracts the earth's rotation will transform the photos you can take, it depends how much you want to spend and if you're in it for the long term.

Edited December 16, 2022 by Elp

[Stickey]

I echo previous comments, you can make a good start with the kit lenses. I've done exactly the same, but for a tracking mount, I started off with an Omegon MiniTrack on a standard photo tripod. It's clockwork and cheaper than the usual camera tracking mounts and I picked it up from one of the astro market web sites. Not as good as a proper tracker, but doesn't need batteries or power supplies and got me started. 

 

[rickwayne]

On 15/12/2022 at 23:27, Bklynse said:

1) Are these lenses sufficient for astrophotography or do I need to get a better lens?

2) If I need to get a better lens, what should I get: a zoom lens or a fixed lens?

3) If I am going to take pictures of the Milky Way or of planets and stars, do I need an equatorial mount?  If not, how can I counteract the east-west motion of the earth during long exposures?

Regards

 

1) They're certainly sufficient to start. You won't get very long exposures without a tracking mount of some kind -- the "300 rule" is a reasonable heuristic. (Divide 300 by the focal length to yield the maximum exposure that won't yield star trails.) Your results will drive what you'll need. Between the extremely high contrast and incredibly fine detail of astrophotos, it's a challenge for any lens. So the fewer compromises, the better. Kit lenses are zooms (compromise) and inexpensive (more compromises). Stopping down a bit, or placing a mask with a circular hole in front of the lens to provide a perfectly round aperture, can help.

2) Definitely go for primes. Autofocus doesn't work so you can look for cheap old used manual-everything glass. This image, for example, is from a 1970s-era 50mm macro.

3) Those are three pretty different kinds of targets! The Milky Way often does well with wide lenses to include the landscape, which (see "300 rule") means reasonably long exposures without trailing. So no EQ needed. Planets are tiny and super-bright (they're in full sunlight), so the favored technique is to use long focal lengths and shoot video at the highest frame rate possible, out of which the processing software selects and stacks the frames with the least atmospheric disturbance. (I use 1600 or 2432mm telescopes for planets.) You can get away without an EQ mount, though it's a bit tedious to repeatedly reframe. For deep sky objects (e.g. nebulae), except for the very brightest, some kind of tracking EQ mount is an absolute requirement.

And the answer to "how much does a tracking EQ mount cost?" is, of course, "How much ya got?" You can build a barndoor tracker for very little that will do short exposures up to 2-300mm; you can buy a camera tracker that will yield somewhat longer exposures and handle longer focal lengths; or you can get anything from a US$800 to US$10000 equatorial mount, whose performance scales nonlinearly with price. I went with the US$800-some option for my first mount and did pretty well from 350-900mm.

[imakebeer]

I only started AP a few months ago (Oct '22).

Although I've now got a bigger scope + tracking mount, I'd say you can absolutely achieve quite a lot with your gear, as long as you have a tripod too (even a simple fixed one).

As a jumping off point startrails are fun and easy 👍

I have a Nikon D5500 + 18-300mm lens and I started off with this on a fixed tripod and was able to image M31 (Andromeda galaxy - skip to first & penultimate posts) and M45 (Pleiades) - I daresay M42 (Orion nebula) would work too (i.e. brighter objects).

I don't think your DSLR or 200mm lens would be radically different. I found I was limited to about 5s exposures before the star trailing became unacceptable. The trick will be to take many light frames (50+, 100+, maybe more, plus darks, flats & bias) and then use software to stack them and post process.

Your Nikon might have a built in program to take many exposures (mine does), otherwise you'll need some sort of remote shutter release or computer to control it (e.g. laptop + BackyardNikon).

At the moment I've gotten carried away with my new scope & mount (still using the DSLR with it though!), but I think there's a lot to be said for such a light, simple and portable setup as a DSLR + lens + fixed tripod.

I haven't tried any Milky Way stuff yet, in any form so can't comment.

But my initial astrophotography attempts were actually planets - I used the D5500 again, with my daughter's telescope (SW Capricorn 900mm/70mm refractor) on a manual EQ1 mount, an eyepiece protection adapter and BackyardNikon again. Sounds a lot of stuff maybe but it's really not an extravagant setup!

So yeah, I think you can do a lot with what you have, and maybe not too much more. Just be aware as others have said it gets addictive, it's as much about the post processing software afterwards as it the actual picture taking, and be mindful that while one can do a lot we're all still limited by the equipment we have.