Using DSS

[thing]

I've just (between the cloud belts....) managed to grab 5x1 minutes of M51. The pics on their own show up M51 so I thought I would try stacking them using DSS. I followed the constructions, added some offset frames and dark frames, and the resulting picture showed about 3 stars and certainly no M51. Anybody any ideas?

[Andrew*]

Have you played with these sliders?

(click to enlarge)

Andrew

[thing]

Nope.

[Beyond_Vision]

The picture thrown up at the end will have a logrithmic stretch applied and will look awful. Click on the RGB levels tab then click on the linked settings check box. Now click on the where it says LOG on the left hand end of the sliders then choose ASINH or Linear. On the histogram for any of the colours click on one of the central sliders and adjust the postion of the histogram peaks to be sat on the steepest part of the curve. Then click apply at which point you should see something half reasonable. From this point have a play with sliders to see what effect they have. I usually have to tweak the saturation and sometimes adjust the luminance then save with changes applied.

Regards

Kevin

[thing]

Thanks for the info guys, I had a fiddle but no luck. One thing I did notice was I'm stacking 5 frames (or at least i think I am) and the end product which is a tiff file says 'one exposure 30 secs at ISO 800'. Shouldn't it have added all the exposure time up? When I registered the shots it gave me a total exposure of over 4 minutes.

[aries]

Nope.

:laughing8: :laughing8: :laughing8: :laughing8: :laughing8:

[Kaptain Klevtsov]

IF DSS decides to work its great, but I've no idea why its does when it does, or doesn't when it doesn't. There is an option where you can tell it what percentage of the frames to use I think, which might be it, or maybe you didn't check all frames?

If anybody could point me to a tutorial on DSS I'd be grateful as it hates me as much as I hate it.

Kaptain Klevtsov

[Apatchy]

Thanks for the info guys, I had a fiddle but no luck. One thing I did notice was I'm stacking 5 frames (or at least i think I am) and the end product which is a tiff file says 'one exposure 30 secs at ISO 800'. Shouldn't it have added all the exposure time up? When I registered the shots it gave me a total exposure of over 4 minutes.

I had the same trouble with it only stacking 1 frame. If you click on register checked pics, when the register settings box comes up click on advanced and click compute number of detected stars, when i did this it only came up with 1 so i adjusted the percentage to 3 and clicked compute number of detected stars again which then came up with 73 stars i then clicked ok and it then stacked 80 percent of the frames. Hope this helps.

[daz]

thing

Can you upload files to UKA for us to play with?

[thing]

UKA? I deleted the files actually but I've got 3x 1minute of M82 if you want.

[daz]

UKA - UK Astronomers or some other hosting service. I suspect they are too big to upload here.