first DSS stack, CC and tips please

Hey guys.

Here is my first stack with DSS, its only 30 lights and 20 Darks i think, i actually took way more lights and darks but but my lens got covered with dew and ruined about 100 of them

heres the pic and what i did in DSS, when ever i tried to get anything more out of it the bottom of the pic would start to get blown out??? have i done something wrong.
Let me know what you think

i also went about trying to do some star trails but when i go to use startrails.de it says "error in input file", is this because i havent converted them from raw to tiff? if so is there some easy way to batch 300 pics from RAW to TIFF? Im using a 50D if this helps

EDIT: realized it was RAW that was the issue, also figured out that i could use DPP to convert to TIFF in batch
i am currently making the star trail, will post when its done. does anyone know of any tutorials or tricks with Startrails.de the foreground averaging bit is confusing me and i dont know wether more or less pics are better

cheers
Damien

HOSTED PHOTO
please log in to view hosted photos in full size.

HOSTED PHOTO
please log in to view hosted photos in full size.

well heres my first star trail, next one i will use a higher ISO to make sure the stars are brighter. i will also put in a better fore ground, im spending 3 months up at the mountains working as a snowboard instructor so im will try lots there

Damien

HOSTED PHOTO
please log in to view hosted photos in full size.

Nice images, Damien. What were the lens and exposure parameters (focal length, time, f/ratio, ISO)?

Try taking the widefield shot into Photoshop if you have it to tweak the levels and curves. It's pretty hard (impossible?) to get optimal results with the DSS post-processing tools. DSS is great for calibration, registration and stacking, but the best advice (even the author of DSS suggests it) is to take the stacked result into another application for final adjustments. When you save the results from DSS, be sure to select the option to embed the adjustments made in DSS but not apply them. What you will see in Photoshop then will be very dark, nearly black - but all the data will be there, and adjusting levels and curves will allow you to bring it out.

The reason that the bottom gets blown out when you try to optimize in DSS is that there is a significant brightness gradient in the sky, combined with the clumsy interface in DSS. You will be able to do better in Photoshop, but ideally you should use a gradient removal tool. There are several add-ons to Photoshop that can do it, such as Gradient Xterminator and Noel Carboni's astro tools. It can also be done in Photoshop without any add-ons but that is a bit more complicated.

Don

I made a quick and dirty attempt at enhancing your widefield shot in Photoshop. I used the Levels, Curves, Color Balance and Channel Mixer tools, along with Photoshop's built-in Gradient tool.

I'm sure you can do better starting with the full 16-bit image.

Don

HOSTED PHOTO
please log in to view hosted photos in full size.

the star trails are nice

HI, thanks for that Don and Sniper, will pull my widefield shot into light room and give it a try

they were taken as follows (both with 17-85)
widefield: 17mm, iso 1600, SS 25 secs, AP 4.0
star trails: 17mm iso 200, SS 30 secs, AP 4.0

i also have a 8mm bower fisheye that i am planing on taking star trails with but i was finding it impossible to focus/pick out on stars even when using my laptop with remote live view, can i just focus on something in he distance during the day time and use that at night because it has such a short focal length??

cheers, Damien

Nice, do you have anything to fight the dew?

For a quick fix, buying a 12v jump start battery from home depot/lowes and a 12v hair dryer will help clear the dew up, but it only lasts for so long. As things dew up the dew will return to the lens more quickly each time. It's the cheapest option though. Make sure you get a 17amp/hr battery, the 7amp/hr batteries won't last too long.

The other option is what we use with telescopes. Buying a dew heater strip and a controller will give you continuous heat applied to the lens to keep it just warm enough to keep dew off the optics.

Something like the 1000 oaks controller is nice, you get 4 outputs, so if you ever get a telescope you can run mulitple heaters.
http://www.optcorp.com …&kw=dew%20contr​oller&st=2

Then for strips the best and actually not the most expensive ones out there would be Dew-Not.
http://www.dew-not.com/Order_Form.htm

Measure the circumference of your lenses you use and buy a strip big enough to wrap around the largest one.

Another good way of fighting the dew is to use hand warmers. I keep a box of those in my trunk and break open 2 or 3 of them before I start shooting. I wrap them around the lens with a thick rubber band. Once they heat up you'll be golden.

cheers for those tips guys, i may grab a couple of those hand walmers and give it a shot

taccca wrote in post #10322112
cheers for those tips guys, i may grab a couple of those hand walmers and give it a shot

The handwarmers do the trick as well but if you shoot often or for long periods of time going with the strips is the way to go. Handwarmers last between 6 and 8 hours usually and you'll need several of them wrapped around the lens/telescope to evenly heat the glass. The 1 issue with them is that they require some kind of insulation, like being in a pocket, so you can't just rubber band them to a lens and expect them to last as long or stay as warm as in a pocket. A piece of material wrapped around the lens to hold them on that is thick enough to help keep the heat on the lens would likely help a lot.

When my dew heater blew a fuse 1 night I stuck about 8 hand warmers in between the dew shield (long plastic extension at the front where the telescope lens is) and the telescope, it held them on there tightly and they lasted for 2/3 of the night. Long nights or REALLY bad nights may require more warmers.