Advice on DSLR lens for beginning Astrophotography?

[StarBru]

I got a smoking deal on a refurbished Canon EOS Rebel T5 that I couldn't pass up! It doesn't have a lot of features that a T5i, T6i or T7i has, but the price was right and if and when I see enough success with my images, I can always trade up. The lens I bought is a Canon EF-S 18-135mm f3.5-5.6 IS STM zoom.

My question is: What is a good lens for taking unguided or guided images with just the DSLR and a lens? Is my 18-135mm lens enough to start? Somewhere I read that a Rokinon 14mm f2.8 wide angle fixed lens would be a good choice. I am also thinking of a used Canon EF-S 17-55mm f2.8 IS USM zoom lens I can get for about the same price as the new, open box Rokinon, which is $200. Or are there better choices out there. Any advice?

[jrkirkham]

I usually just use what I have until it starts getting in the way of what I want to shoot. I once used a lens similar to the one you are using, but I just couldn't get it to shoot fast enough for the nightscapes I wanted. I switched to the Rokinon 14mm f/2.8. Your cameras are not full-frame. Rokinon also made a 16mm f/2.0, but it will not work on full-frame cameras. I like them both. They are good for star trails, nightscapes, milky way, etc. They don't have enough kick for DSO work. Between the two I would go with the 14mm, unless a found a good used 16mm for a much lower price.

I've never used the 17-55 so I can't comment on it.

[StarBru]

I usually just use what I have until it starts getting in the way of what I want to shoot. I once used a lens similar to the one you are using, but I just couldn't get it to shoot fast enough for the nightscapes I wanted. I switched to the Rokinon 14mm f/2.8. Your cameras are not full-frame. Rokinon also made a 16mm f/2.0, but it will not work on full-frame cameras. I like them both. They are good for star trails, nightscapes, milky way, etc. They don't have enough kick for DSO work. Between the two I would go with the 14mm, unless a found a good used 16mm for a much lower price.

I've never used the 17-55 so I can't comment on it.

I haven't been able to find the 16mm f/2.0 for the price I want. The 14mm f/2.8 for EF-S mount is listed as New/Open Box by a camera shop and is going for $199 delivered. It's for the EF-S mount, and $50 off the price of a new unopened one. Seems like the one I want.

I know my camera is not full frame. I have always liked the smaller SLR's when I started out with photography back in the days of film.

[StarBru]

I just bought the Rokinon 14mm f/2.8 lens I mentioned above for $10 less, new, open box. I also ordered a t-ring for attaching the camera to my telescope. I should already have the appropriate adapters for 1.25 and 2" for the T-ring, I'm not sure, though. I'm supposed to be receiving everything by September 6th. Can't wait to start my new adventure in astrophotography!

[JayTee]

Bruce,

Did you decide to go with "overkill" and use your EQ6-R with just the camera attached? You'd be hard-pressed to get more stable than that.

Cheers,

[StarBru]

Bruce,

Did you decide to go with "overkill" and use your EQ6-R with just the camera attached? You'd be hard-pressed to get more stable than that.

Cheers,

I will probably just try a regular tripod at first, then maybe a piggyback of the lens and camera on the telescope. I need to start with the basics. I know I will be frustrated at first, with many, many failures to get what I want, so the simpler, the better!

[Graeme1858]

Can't wait to start my new adventure in astrophotography!

Good luck Bruce.

Can't wait to see your work!

Graeme

[SkyHiker]

For tripod photography, keep in mind that the exposure time is roughly limited to 500 divided by the focal length in mm. For that you would benefit from a lens with short focal length. The objective would be Milky Way landscapes, featuring an interesting landscape background. A 135 mm lens would be limited to 3 seconds. The nifty fifty at 17 mm would get you 20 to 30 seconds.

If you put your camera on the EQ6R you would aim for long exposure DSOs at 135 to 300 mm, a completely different objective. For that, a 70-300 mm zoom lens would be good. Polar alignment will be an issue but more importantly, finding the target that you cannot see. Doing that with a DSLR is rather daunting so at that point you will benefit from a guide scope that you can use for that, or piggyback on a regular autoguided scope that does the plate solving and forget about your DSLR pretty quick. Just a DSLR and a lens on an EQ6R is not enough.

[StarBru]

For tripod photography, keep in mind that the exposure time is roughly limited to 500 divided by the focal length in mm. For that you would benefit from a lens with short focal length. The objective would be Milky Way landscapes, featuring an interesting landscape background. A 135 mm lens would be limited to 3 seconds. The nifty fifty at 17 mm would get you 20 to 30 seconds.

If you put your camera on the EQ6R you would aim for long exposure DSOs at 135 to 300 mm, a completely different objective. For that, a 70-300 mm zoom lens would be good. Polar alignment will be an issue but more importantly, finding the target that you cannot see. Doing that with a DSLR is rather daunting so at that point you will benefit from a guide scope that you can use for that, or piggyback on a regular autoguided scope that does the plate solving and forget about your DSLR pretty quick. Just a DSLR and a lens on an EQ6R is not enough.

Thank you for the suggestions. I need to start with baby steps, right!?

I'm just now learning all this about my camera and lenses. My Canon Rebel T5 accepts EF and EF-S lenses. Because my Canon T5 is a crop sensor camera, it has a 1.6x factor for any lens I attach to it. So my 18 - 135mm zoom lens is equal to a 28.8 - 216mm zoom lens. If I understand it correctly, with the lens set at 28.8mm, I have about 17 seconds on a tripod and for my Rokinon 14mm lens, I have only about 22 seconds! I will be pretty limited as to what I can capture in by backyard, but at a dark sky sight it would be better.

Attaching the camera and lens piggybacked on my EQ6R mounted telescope will of course, as you know, allow me to increase those exposure times for the Milky Way shots. But to make things lighter and more simple I also have a Meade LXD-55 EQ mount with Autostar, my Meade ETX90 -EC with Autostar in polar position, and even my Meade 4" 2045D AC-powered RA drive. That EQ6R is heavy! My intention is to have a small observatory so I can keep it set up and not have to move it, but that's a whole other subject.

As much as I want to tackle photographing DSO's, I will need to try just the DSLR and lenses first on Milky Way, then maybe some moon and planet photos through the telescopes. DSO's, forget about it! Maybe sometime in the distant future?