Basic widefield with a Camera and Tripod

[engstrom]

I was going to use the auto-focus on a distant light source like a streetlight as suggested in the initial post then switch to manual focus but I had to go manual all the way...and my skills were weak.

[engstrom]

I've been using Lynkeos and Nebulosity to experiment with the RAWs from my DSLR that I took at the start of June. The shots were out of focus, lots of LP and not enough subs but I persevered trying to learn the programs rather than produce something nice. I think I've got it now...well...on my way to getting it. I think I managed to pull out some detail that wasn't immediately apparent...the rest of the shot looks like some Lomo art experiment though...and the trial version of Neb leaves coloured lines on the final image :-)

[todd8137]

ermm i do not have dark skies i did some 20 secs and did not get results like this but only have a 28mm/80mm zoom lense so 28mm is the lowest it will go i did about 30 subs and still did not get a result like yours a dark site may be needed a think

[engstrom]

You can find an example 15s sub on a 450d nifty 50 f/1.8 here

[todd8137]

hi well a tried some 30 secs the other night heres the link tried to get some more last night but very damp here heres a link to the blog and pics

http://stargazerslounge.com/blogs/todd8137/815-start-my-mega-wide-field-shot.html

[HumanEnergy]

That's a nice, easy to follow write up. Gonna give this a go at the weekend if I'm lucky with the clouds. My widest lens is 16mm so if I stick with 30 second exposures I should get a little bit less star trailing than with an 18mm lens.

[assouptro]

Great write-up John.

I've been shootong DSO's mainly but am beginning to appreciate and enjoy the "bigger picture" as it is easier to transport and set up the equipment, and you can get some dramatic pics if you can get an interesting terrestrial object in the field of view (FOV).

you have definitely given me some tips I will be trying.

Thanks for sharing.

Bryan.

[todd8137]

RAW is much better for this, you can use jpg, but the results will not be as good. If you install the Canon Zoombrowser EX you can use that to view the images this is what I use... or have a look at

ImpulseAdventure - RAW Thumbnails in Windows XP

thats a great quick view thanks

[c3po]

a great tutorial John, very handy and will most certainly come into use over the next few weeks with me as i'm just getting started in Astronomy.

You mention using a DSLR, and although I agree that they will give the best images, what could beginners expect from 'point & shoot' or 'bridge' cameras following the tips you posted?

Are there any special settings to use? Would a shorter max exposure (15 seconds for example) be detrimental to the overall photo detail?....

Thanks,

C3PO

Edited January 20, 2012 by c3po

[jgs001]

I used to use a bridge camera, and it worked (not sure I could find them now...). The quality was never on a par with my SLR... the biggest issue I had with it was focusing... it's bad enough trying to focus an SLR when you can manually tweak the focus point... but with my bridge camera, it was just an on screen option, adjusted with an arrow (up or down)... so really really hard to do. Of course, other cameras may have better implementations. As for a shorter exposure, you will capture less information. Having said that, if AP is something you want to aim at, the processes involved are generally the same, so it's all a good learning experience.

[c3po]

I used to use a bridge camera, and it worked (not sure I could find them now...). The quality was never on a par with my SLR... the biggest issue I had with it was focusing... it's bad enough trying to focus an SLR when you can manually tweak the focus point... but with my bridge camera, it was just an on screen option, adjusted with an arrow (up or down)... so really really hard to do. Of course, other cameras may have better implementations. As for a shorter exposure, you will capture less information. Having said that, if AP is something you want to aim at, the processes involved are generally the same, so it's all a good learning experience.

Hi John, excellent info. Many thanks for that! I've gotten to know the camera well having used it (a Fuji S7000) for shooting many thousands of daytime RAW images (all shot using 'full manual' mode) at air shows on and such over the past few years and am now quite attuned to its quirks and limitations - hopefully AP will teach me something new about it after all this time!

[the milster]

Good stuff, just what I was looking for

[nipper]

This is perfect information to start off with my new (second-hand) Canon 450D and tripod.

[Paulus17]

Great write up John and summat i want to have a go at next time i'm out,but do you take the ten shots straight after each other,and then five with the lens cap on?

How accurate do the timings need to be as i tend to count my exposures times??

I alwyas wondered what he lights and darks were:confused:

[jgs001]

Yep, that's about it... For these short exposures, I just use the built in exposure timer, not in bulb mode. I think, a second or so either way, isn't going to make any noticeable difference.

[Paulus17]

Thanks John:)

Do you have to take half the amount of darks as lights all the time.So if i do 20 lights i need 10 darks,40/20 and so on??

[jgs001]

no, I used to do 5 for this sort of thing... For long exposures (5 minutes or more) the more the better, but I aim for a minimum of 10, but can't normally be doing with more than 15 (it takes too long).

[Rosencratz]

Great read. I've been meaning to learn how to stack my photos for a while now. Sadly my last trip out I only remembered to take 1 dark field shot.

So I shouldn't expect much impact from that?

As an aside though I noticed a lot of mention of how long the exposure should be and thought it might be handy to mention a little rule of thumb I picked up from thestartrail.com (Ben Canales).

The rule is that you divide 600 by the focal length of your camera.

So if you're using a 50mm lens you do:

600/50=12s

This only counts for the "effective" focal range though so if you're using a crop sensor camera (like me, if you're using full frame you'd know it) you also need to apply the crop ratio to your calculation. Usually this is about 1.5.

To save time you just adjust the original calculation to:

400/50=8s (because 400 is 600/1.5)

Generally I only ever go out intending to use one lens. (my widest one with biggest aperture) and so I can easily do the equation before I even leave the house.

I'm under the impression that the finer details of the calculation will show that the angle of the camera will also effect the timing some how too but you'll find the above value in seconds to be about right. It works for me. Some times I take a second or two off to be safe though.

It may be common knowledge but it totally streamlined my workflow when I get on site.

[allcart]

Good info on this thread. shame I didn't find it before I asked the question elsewhere on here.

[allcart]

Just checked out Ben Canales video's. Its quite good, but it was hard to hear what he was saying due the the music that was playing along with the video. Can it be turned off I wonder.

I can't figure out how you can do a 30 sec exposure at max ISO and not get star trails.???

[Scott]

great thread. thanks for starting it john, looking forward to putting it into practice.

[Matt Scunthorpe]

Im just getting into wildfield photography as i can't get the scope out as much with my mum being ill, I will give this guide a shot and see how i get on.

Thanks,

[stargazerlily]

Brilliant John, many thanks for sharing. Definitely going to try it out.

Some quickie questions ...

Are you setting the camera to Shutter priority mode or Manual mode

Is there a RAW viewer for Windows 7?

When you say 'stop down the lens' are stopping down by 1 full stop in aperture or using exposure compensation?

Many thanks

Pete

[jgs001]

Pete, I use manual mode, in fact, I very rarely use any other mode even for normal photography .

I'm not sure on a raw viewer for windows 7, there are a number of plugins that worked for windows xp, and there are applications, Canon's zoom browser EX I use for my astro images, download and pulling into DSS (but then I'm running DSS in a VM on a Mac )

[stargazerlily]

Thanks John.

I'll do a G-search for raw viewers on Win7, see what comes up.

Pete