Why are my Milkyways so dim?

[ourkind]

I'm still struggling to capture the milky way where it really stands out in the photograph, this was only a 15sec exp at 3200ISO Canon 60d, even at 30 sec ISO 3200 it still seems dim.

Is the answer a Polaris? or does the MW need to be further edited with software?

The first image is 15sec the second image is 30sec both ISO 3200.

Thanks and looking forward to some advice.

[Octane]

You didn't mention what lens you're using, Carlos.

The shots taken by the guys in this forum are taken with f/2.8 (and, faster) lenses.

H

[colinmlegg]

What aperture are you using, Carlos? Even at 3200, f/2.8, 30 sec, you'll still need to boost the contrast a bit to get it to stand out.

[ourkind]

Right is see, so a lens with an f stop 2.8 and quicker will collect more light in the same amount of time and give me more highlights, cool (I learn something new everyday, love it).

I'm using this exact lens http://www.the-digital-picture.com/Reviews/Canon-EF-S-10-22mm-f-3.5-4.5-USM-Lens-Review.aspx

Canon EF-S 10-22mm f/3.5-4.5 USM





Both images were at 10mm.

I believe the aperture on the lens is 77mm that right, it seems smaller when I look at it?

[ourkind]

Thanks Humayun and Colin for your quick replies, is there a quick enough lens I could get for under $1000?

[Littlestar]

Probably worthwhile to try a tracking mount under $1000:rofl:

[LAW]

The canon "Nifty 50" or "plastic fantastic" or "Canon EF 50mm f/1.8 II".

If you can't find one for less than $100 you're doing something very wrong.
This lens is possibly the single best 'bang for buck' piece of equipment available from Canon. It's fast, sharp and cheap, which makes it an essential part of my astro cupboard.

But I'll agree with Gordon, if you've got a 'casual grand' to spend, buy a tracking mount. :D

[ourkind]

haha yeah but then my landscapes will get blurred right?



Nifty 50 less $100 :eyepop: I'm onto it!! thanks!!

[bloodhound31]

77mm is the diameter of the thread on the front of the lens, for screwing on filters and stuff. Pay no attention to it in this case. (If you have a UV filter or any other kind of filter on it now, take it off for your astro-work).

"Stops", loosely explained are a measurement of light, which can be controlled into a camera by opening the aperture, or adjusting the shutter-speed. Even the power, (light) output of your flash is measured in stops.

What you need to know is that the largest aperture your particular lens can open to, (the blades inside that open and close to different sizes) is f/3.5. At 10mm, yours can open as wide as f/3.5, but you zoom in to 22mm, the widest, (fastest) your aperture can open is f/4.5. The wider you can open your aperture, the more light you let in, and the faster it gets in. The smaller the f-number, the wider (faster) the aperture is.

This has nothing to do with wide-angle.

The widest ANGLE or field of view, (FOV) is at 10mm, that is, the piece of glass at the back of your lens, (inside) is only 10mm away from the sensor's focusing-plane inside your camera body. Take your lens off and look into the back of it as you zoom in and out. See how the glass moves. To understand this mechanism, grab a piece of paper and put a small hole in it. Hold the paper up to your eye nice and close. Notice how much you can see in the room? Now hold the piece of paper at arms distance and see how much you can see through the hole. This is your field of view. (FOV) A zoom lens is the same, in your case, 10-22mm away from your eye (the sensor).

I hope this helps mate. Apologies if I've insulted your intelligence, but I don't know what level of understanding you are at. (This may also help others).

Baz.

[LAW]

I had previously thought I was somewhat knowledgeable regarding DSLRs and I just learned something.
"Everyone you will ever meet knows something that you don't" -Bill Nye

[ourkind]

Baz you have not offended me whatsoever infact thankyou for spelling it out for me so clearly. I've re-read your comment and I am now that little bit more knowledgeable. I did as you said and zoomed in and out while looking at the back of the lens and it makes sense, plus I can also see the difference in size of the back glass between my 2 lenses both being EFS 10-22mm and 22-200mm.

I also moved the f/stop wheel aswell whilst at 10mm and it stops at 3.5 then zoomed in to 22mm and the f/ stopped at 4.5.

Thanks Barry for taking my understanding of camera optics to the next level :thanx: I really DO appreciate it.

[iceman]

The answer:
14mm Samyang f/2.8 and post-processing.

[CapturingTheNight]

As Mike has stated a lot of it is in the post processing to really make the MW pop. As an example look at my youtube vid here http://youtu.be/ZJpNkXBvPjs In the very last sequence I show the raw unedited images that went into my "Midnight Rainbow" image and then the 'after' version.

The 50mm F/1.8 'nifty fifty' is a great lens and should be in every Canon users kit but it is not very wide for landscape Milky way shots. You would also be limited to about 8 second exposures with it before the stars trail too much.

The 14mm that Mike also mentioned is probably the best bang for your buck astro landscape lens. It will give you all the goodness of F/2.8 but on your crop sensor 60D I wouldn't push your exposure times past 20-25 seconds. 30 seconds is a fraction too long for that lens/camera combination.

Having said that, your 10mm at F/3.5 certainly isn't a slouch and is more than capable of producing the goods. Thats what I used to shoot with before I went full frame and the 14mm F/2.8. Some examples of my earlier work at 10mm and at F/3.5 http://500px.com/photo/5419839 http://500px.com/photo/5224879 http://500px.com/photo/3584589 http://500px.com/photo/3979581 http://500px.com/photo/6101196
Cheers
Greg

[LewisM]

Carlos,

I took the liberty of fiddling a little bit with one image in PS 5. Being a jpeg, I cannot stretch it too far at all without pixellating it, so tweaked contrast, tones etc, but still a low res jpeg limits the processing ability (post up a TIFF or even a PNG)

The first image was unworkable because of jpeg artifacts and the light in the lower right.

Not much difference, but enough,but you can really see the jpeg artifacts coming through. Do ALL processing on RAWs and TIFFs (even png or dng). I know you know this, but never even think of processing a jpeg - usually not worth it (I take it you always shoot in RAW?)

[mithrandir]

Or for a bit more than twice the money, Tokina 11-16mm f/2.8

[gregbradley]

This brings up a question for me. With telescopes aperture rules. So 150mm aperture scope at F5 is going to be brighter than 100mm scope at F5 - right? Albeit at a narrower field of view.

So with camera lenses, even if 2 lenses are both F2.8 wouldn't the one with the wider aperture and same focal length be superior in collecting light.

I think the fact of aspherical lenses complicates the light gathering process as they are usually quite wide in aperture and thus must be collecting a lot of light and then bringing it to focus very rapidly so the focal length is short.

The downside is microlensed chips mean that light coming in at too sharp an angle will reduce sensitivity as the pixels often require light coming in within a 15 degree angle for their performance.

Anyone know more about this?

I may conduct an experiment my Nikon 14-24 front element is quite wide and seems to collect a lot of light. Would a narrower 14mm F2.8 collect less light even if the resulting optical result is 14mm F2.8???

Greg.

[Octane]

My understanding is that they collect the same amount of light (the aperture is the relationship between the focal length and the lens opening, which means, no matter what lens you use, the same amount of light is reaching the sensor for a given aperture), however, the longer focal length image will have superior resolution.

Want more light? Need more exposure.

H

[Poita]

+1.

Carlos, just buy one of these, it is perfect for what you want to do.

If you have the money, go to the Tokina mentioned.

[LewisM]

I use a Sigma 10-20mm with excellent results. Might post some later :)

That lens is only APS-C suitable - BAD vignette with the full frame sensors.

[gregbradley]

Makes sense. But I was wondering if the exception is an aspherical lens where they seem to have very large aperture like a fisheye or for example the Nikon 14-24 which has a large bulbous front element which must be 77mm in aperture. The aspherical lens is curving that extra aperture more severly so its still ending up 14mm and F2.8 but the light is more bent to arrive at the sensor. Not sure.

Greg.

[ourkind]

Thanks Mike! That's a reasonable price tag.



Thanks for your comments Greg :) I'm still a novice to photography and only at the tip of the iceburg with post editing. I've seen some youtube tutorials on creating masks to highligh certain areas of the image without blowing out areas you want untouched. I need to set some time aside to go through these tutorials and practice these techniques. The good thing is that all my images are taken in RAW so I can definately go back, practice and tweek them.

Also thanks for restoring the faith on my 10mm :) The 50mm sounds very good too, currently have a bid on one, just under $100 looking forward to picking it up this week!



Thanks for that Lewis! :) Yep I appreciate the jpeg issue, good thing I have them in RAW too. I'm going to check out some post editing tutorials and have a play with masks. I only have PS6 (no pluggins - that kinda goes over my head at the moment), that should be good enough for a start?



Thanks Andrew :)



Yep definately food for thought! :)

[RB]

Carlos, I like the 10-22mm and have used it a few times.
Here's a shot I did in 2005, (http://www.iceinspace.com.au/forum/showthread.php?t=3809&highlight=Milky) when I was just starting out in Astro.
At the moment I have limited internet access but when I'm back online I'll post a bit more info.
There's the link to the original thread if you want to read it.

The photo looks dated now but just wanted to share what can be done with just a cheap mount and the 10-22mm.

I like the specs on Mike's suggested 14mm though, might look into one myself.

:thumbsup: