[GWARmachine]

I just meant that the AA's you're using should be fine. I would shoot all night with my K-x on the same batteries. Gotta try those Energizers I mentioned. They are seriously worth the extra couple bucks.

[cadmus]

... Gotta try those Energizers I mentioned. They are seriously worth the extra couple bucks.

Yeah. When i can not recharge and weight is an issue that is the brand and model i use. Lithium Ultimates. They last a long time and they don't heat up much. I frequently am on trips where i have no access to electricity for a month at a time. I normally leave on a trip with a bunch of those and then have to buy alkaine AAs if those run out. It is nice being able to BUY batteries in any shop in any country. When will the other manufacturers catch on to this?

[smigol]

Could someone with a K5 pm me with some assistance regarding your camera? I'm curious about looking at some raw files.

[GWARmachine]

Friends,

While helping out a fellow member here in the forum I just found out that during long exposures, bright light will enter though the rear view-finder and makes its way to my camera's sensor(K-5). I honestly had no idea that this occurred during photography. I'm somewhat sad about this but now I know for my future photos I will be sure to also cover up the exposed glass. I just wanted to share my experience with everyone here.

[smigol]

Note that not only can light enter through the viewfinder for long exposures like GWAR mentions, if you have a poorly fitting lens/camera mount, light can make its way in there as well. Gaffer tape will cover both nicely, albeit a little ugly.

[GWARmachine]

Note that not only can light enter through the viewfinder for long exposures like GWAR mentions, if you have a poorly fitting lens/camera mount, light can make its way in there as well. Gaffer tape will cover both nicely, albeit a little ugly.

Yeah, that's what I was afraid was happening. (This is also why the darks took so long. I though I was doing something wrong.) So I did some experimenting, holding a small light at all the places I thought light may be coming through; at the lens cap, at the lens-to-body connection, even at the range view thing on the lens. My very last guess was exactly where the light was coming in at. Not happy about it but glad I know now.

[smigol]

That's why I do my darks in the fridge. Easier to build up the library of temperatures that I want. By strategically placing a cloth over the camera or resting it against different things and giving a longer duration between shots helps create different camera temperatures. Takes a while to do it, but you can do it anytime.

[Stone G.]

There are many great photos of the Great Nebula in Orion on these pages. The below isn't one of the greatest but about what I can accomplish this time of the year when light pollution and unsteady air conspire agianst my astrophotographic ambitions:


20 images of 10s at ISO6400 stacked in Registax and contrast enhanced in PhotoImpact.

As with many photographs of this nebula the inner core around the Trapezium is overexposed as the price one pays to get more of the fainter outer nebula.

So, here is a view of the Trapezium and surroundings at a lower exposure value:


Contrast enhanced stack (tighter crop) of 10 images of 4 seconds at ISO 1600

Now blend these two images to get this:


Blend of the two stacks above using layers and "Luminosity Only" - plus a bit more of fiddling with curves and levels.

I think this could be worthwhile pursuing when weather and observing conditions improve?

[gapalp]

I really just glanced through this thread so what I say here may have been repeated. Here is my personal experience:

Any DSLR on a tripod could be used for widefield astrophotography. Thats a great place to start. Going beyond widefield with a DSLR alone brings along with it more time involved and expense.

If you want to image deep sky objects (DSOs) more than M42 (Orion Nebula) you will want to move to using a DSLR on a scope. If you have LiveView and complete computer control of the DSLR, really any brand DSLR could easily be attached to a scope using the correct T-Mount. No LiveView will make focusing difficult and no computer control will make your sessions difficult but it can be done with DSLRs without those options. But those two things are huge time-savers in astropotography.

A good starting point is a small focal length refractor and a quality mount with the ability to use an autoguider. Some astropotographers have in their arsenal a longer focal length scope on an excellent quality mount for capturing images of smaller galaxies, planetary nebulae, etc. Most who use DSLR in astro imaging modify their cameras to remove the filters that block certain wavelength light that DSOs emit. Doing this captures a better picture and makes them more like CCD cameras that are specifically made for astro imaging. Once you start using telescopes you start getting into polar alignment, dew management, and a bunch of other factors to control. It takes me about an hour to setup all my equipment, get it aligned, then start imaging with it. Then some of us get so addicted to it we have to build a permanent building in our backyard to house our equipment so it is "permanently" setup and one can be imaging with it in 5 minutes.

Thats my experience in a nutshell. As with any hobby there is a wide range of how deep you can get involved. It seems to involve how much time and money you want to invest. I am actually getting back into daytime photography. Just got a K200D body and some lenses. I use my Canon 1000D on my scopes. Check out the CloudyNights.com forums in the Begining Imaging section and astropix.com. Lots of great tips on how to involved in astro imaging no matter what DSLR you use or how deep you want to get into it. Now I need to check on my contractors who are building that observatory for me

[zambonikane]

I was hoping someone here could help me. Does anyone use Deep sky stacker? I have been using this piece of software for a while, but I can never seem to get the color balance right. After it spits out the finished file, I align the color peaks in the histogram, but the image still looks too yellow to me. Here s a composite of four different exposures from the Orion nebula that, other than the color balance, I am really happy with. Any ideas?

[gapalp]

I was hoping someone here could help me. Does anyone use Deep sky stacker? I have been using this piece of software for a while, but I can never seem to get the color balance right. After it spits out the finished file, I align the color peaks in the histogram, but the image still looks too yellow to me. Here s a composite of four different exposures from the Orion nebula that, other than the color balance, I am really happy with. Any ideas?

I use DSS for stacking the exposures. Once the stacking is done, I take the resulting TIFF image and edit it in Photoshop. Most don't use DSS for post processing. Try doing levels and curves in a dedicated imaging editor such as Photoshop, Gimp, etc. Don't save any edits to the TIFF when you close DSS.

A good capture by the way, lots of dust detail there! Your levels don't look that much off to me.

[zambonikane]

Thanks for the advice. I usually use photoshop cs 2 or 3 (I forget, it's at work). The color of the ngc 1977 (running man) is way off. It should be blue. Do you know what white balance settings you use? I have read that using daylight is the preferred method. As I type, I am imaging m81 with the daylight white balance setting.

[smigol]

When I use DSS, I set white balance using daylight and tell the software to either use the camera white balance or an automatic white balance depending if I knew that the session was somewhat flawed. I also use a light pollution filter so that tends to shift the colors a bit, compensated by the custom balance. Are you using a grey card to set white balance or are you using the camera preset? If the former, you may want to set the balance using the full optical train in place (ie: use the camera on the scope to set the balance on a distant grey card). Another method if you are concerned about colors, you can find a G2V star and take a picture of that with your setup. Then you can set white balance on that color.

DSS is a tool to help calibrate and register stacks of images into a final, deep exposure. What you do with this final image is up to you.

The important effort should be made on getting lots of clean data in the first place and save that data for later work. Your methods of stacking will improve as you learn your tools and as the tools get better.

[Gimbal]

There are many great photos of the Great Nebula in Orion on these pages. The below isn't one of the greatest but about what I can accomplish this time of the year when light pollution and unsteady air conspire agianst my astrophotographic ambitions:

Have you tried using iso 80 instead of those high iso numbers? You will still find the dust clouds in the shadows and the blown out areas will be much smaller. The iso 80 shots are not fun to look at unprocessed though as they will be very dark.

[zambonikane]

Here are the results of last nights imaging. I changed the in camera white balance to day light then I did some minor tweaking in DSS's image processor. I copied that into GIMP (I did not like my TIFFs) then played with curved, levels, saturation, contrast and unsharp masking. I think I am pretty happy with the results. Now to batch convert all my RAW images for other targets to Daylight WB - Any suggestions on how to do this the most efficiently?
Thanks for taking the time!
Mike